Adding upstream version 6.1.76.upstream/6.1.76

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

30 files changed, 7427 insertions, 0 deletions

diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile
new file mode 100644
index 000000000..ef5045a53
--- /dev/null
+++ b/drivers/firmware/efi/libstub/Makefile
@@ -0,0 +1,170 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# The stub may be linked into the kernel proper or into a separate boot binary,
+# but in either case, it executes before the kernel does (with MMU disabled) so
+# things like ftrace and stack-protector are likely to cause trouble if left
+# enabled, even if doing so doesn't break the build.
+#
+cflags-$(CONFIG_X86_32)		:= -march=i386
+cflags-$(CONFIG_X86_64)		:= -mcmodel=small
+cflags-$(CONFIG_X86)		+= -m$(BITS) -D__KERNEL__ \
+				   -fPIC -fno-strict-aliasing -mno-red-zone \
+				   -mno-mmx -mno-sse -fshort-wchar \
+				   -Wno-pointer-sign \
+				   $(call cc-disable-warning, address-of-packed-member) \
+				   $(call cc-disable-warning, gnu) \
+				   -fno-asynchronous-unwind-tables \
+				   $(CLANG_FLAGS)
+
+# arm64 uses the full KBUILD_CFLAGS so it's necessary to explicitly
+# disable the stackleak plugin
+cflags-$(CONFIG_ARM64)		:= $(subst $(CC_FLAGS_FTRACE),,$(KBUILD_CFLAGS)) \
+				   -fpie $(DISABLE_STACKLEAK_PLUGIN) \
+				   $(call cc-option,-mbranch-protection=none)
+cflags-$(CONFIG_ARM)		:= $(subst $(CC_FLAGS_FTRACE),,$(KBUILD_CFLAGS)) \
+				   -fno-builtin -fpic \
+				   $(call cc-option,-mno-single-pic-base)
+cflags-$(CONFIG_RISCV)		:= $(subst $(CC_FLAGS_FTRACE),,$(KBUILD_CFLAGS)) \
+				   -fpic
+cflags-$(CONFIG_LOONGARCH)	:= $(subst $(CC_FLAGS_FTRACE),,$(KBUILD_CFLAGS)) \
+				   -fpie
+
+cflags-$(CONFIG_EFI_PARAMS_FROM_FDT)	+= -I$(srctree)/scripts/dtc/libfdt
+
+KBUILD_CFLAGS			:= $(cflags-y) -Os -DDISABLE_BRANCH_PROFILING \
+				   -include $(srctree)/include/linux/hidden.h \
+				   -D__NO_FORTIFY \
+				   -ffreestanding \
+				   -fno-stack-protector \
+				   $(call cc-option,-fno-addrsig) \
+				   -D__DISABLE_EXPORTS
+
+#
+# struct randomization only makes sense for Linux internal types, which the EFI
+# stub code never touches, so let's turn off struct randomization for the stub
+# altogether
+#
+KBUILD_CFLAGS := $(filter-out $(RANDSTRUCT_CFLAGS), $(KBUILD_CFLAGS))
+
+# remove SCS flags from all objects in this directory
+KBUILD_CFLAGS := $(filter-out $(CC_FLAGS_SCS), $(KBUILD_CFLAGS))
+# disable CFI
+KBUILD_CFLAGS := $(filter-out $(CC_FLAGS_CFI), $(KBUILD_CFLAGS))
+# disable LTO
+KBUILD_CFLAGS := $(filter-out $(CC_FLAGS_LTO), $(KBUILD_CFLAGS))
+
+GCOV_PROFILE			:= n
+# Sanitizer runtimes are unavailable and cannot be linked here.
+KASAN_SANITIZE			:= n
+KCSAN_SANITIZE			:= n
+KMSAN_SANITIZE			:= n
+UBSAN_SANITIZE			:= n
+OBJECT_FILES_NON_STANDARD	:= y
+
+# Prevents link failures: __sanitizer_cov_trace_pc() is not linked in.
+KCOV_INSTRUMENT			:= n
+
+lib-y				:= efi-stub-helper.o gop.o secureboot.o tpm.o \
+				   file.o mem.o random.o randomalloc.o pci.o \
+				   skip_spaces.o lib-cmdline.o lib-ctype.o \
+				   alignedmem.o relocate.o vsprintf.o
+
+# include the stub's libfdt dependencies from lib/ when needed
+libfdt-deps			:= fdt_rw.c fdt_ro.c fdt_wip.c fdt.c \
+				   fdt_empty_tree.c fdt_sw.c
+
+lib-$(CONFIG_EFI_PARAMS_FROM_FDT) += fdt.o \
+				     $(patsubst %.c,lib-%.o,$(libfdt-deps))
+
+$(obj)/lib-%.o: $(srctree)/lib/%.c FORCE
+	$(call if_changed_rule,cc_o_c)
+
+lib-$(CONFIG_EFI_GENERIC_STUB)	+= efi-stub.o string.o intrinsics.o systable.o
+
+lib-$(CONFIG_ARM)		+= arm32-stub.o
+lib-$(CONFIG_ARM64)		+= arm64-stub.o smbios.o
+lib-$(CONFIG_X86)		+= x86-stub.o
+lib-$(CONFIG_RISCV)		+= riscv-stub.o
+lib-$(CONFIG_LOONGARCH)		+= loongarch-stub.o
+
+CFLAGS_arm32-stub.o		:= -DTEXT_OFFSET=$(TEXT_OFFSET)
+
+zboot-obj-$(CONFIG_RISCV)	:= lib-clz_ctz.o lib-ashldi3.o
+lib-$(CONFIG_EFI_ZBOOT)		+= zboot.o $(zboot-obj-y)
+
+extra-y				:= $(lib-y)
+lib-y				:= $(patsubst %.o,%.stub.o,$(lib-y))
+
+# Even when -mbranch-protection=none is set, Clang will generate a
+# .note.gnu.property for code-less object files (like lib/ctype.c),
+# so work around this by explicitly removing the unwanted section.
+# https://bugs.llvm.org/show_bug.cgi?id=46480
+STUBCOPY_FLAGS-y		+= --remove-section=.note.gnu.property
+
+#
+# For x86, bootloaders like systemd-boot or grub-efi do not zero-initialize the
+# .bss section, so the .bss section of the EFI stub needs to be included in the
+# .data section of the compressed kernel to ensure initialization. Rename the
+# .bss section here so it's easy to pick out in the linker script.
+#
+STUBCOPY_FLAGS-$(CONFIG_X86)	+= --rename-section .bss=.bss.efistub,load,alloc
+STUBCOPY_RELOC-$(CONFIG_X86_32)	:= R_386_32
+STUBCOPY_RELOC-$(CONFIG_X86_64)	:= R_X86_64_64
+
+#
+# ARM discards the .data section because it disallows r/w data in the
+# decompressor. So move our .data to .data.efistub and .bss to .bss.efistub,
+# which are preserved explicitly by the decompressor linker script.
+#
+STUBCOPY_FLAGS-$(CONFIG_ARM)	+= --rename-section .data=.data.efistub	\
+				   --rename-section .bss=.bss.efistub,load,alloc
+STUBCOPY_RELOC-$(CONFIG_ARM)	:= R_ARM_ABS
+
+#
+# arm64 puts the stub in the kernel proper, which will unnecessarily retain all
+# code indefinitely unless it is annotated as __init/__initdata/__initconst etc.
+# So let's apply the __init annotations at the section level, by prefixing
+# the section names directly. This will ensure that even all the inline string
+# literals are covered.
+# The fact that the stub and the kernel proper are essentially the same binary
+# also means that we need to be extra careful to make sure that the stub does
+# not rely on any absolute symbol references, considering that the virtual
+# kernel mapping that the linker uses is not active yet when the stub is
+# executing. So build all C dependencies of the EFI stub into libstub, and do
+# a verification pass to see if any absolute relocations exist in any of the
+# object files.
+#
+STUBCOPY_FLAGS-$(CONFIG_ARM64)	+= --prefix-alloc-sections=.init \
+				   --prefix-symbols=__efistub_
+STUBCOPY_RELOC-$(CONFIG_ARM64)	:= R_AARCH64_ABS
+
+# For RISC-V, we don't need anything special other than arm64. Keep all the
+# symbols in .init section and make sure that no absolute symbols references
+# doesn't exist.
+STUBCOPY_FLAGS-$(CONFIG_RISCV)	+= --prefix-alloc-sections=.init \
+				   --prefix-symbols=__efistub_
+STUBCOPY_RELOC-$(CONFIG_RISCV)	:= R_RISCV_HI20
+
+# For LoongArch, keep all the symbols in .init section and make sure that no
+# absolute symbols references exist.
+STUBCOPY_FLAGS-$(CONFIG_LOONGARCH)	+= --prefix-alloc-sections=.init \
+					   --prefix-symbols=__efistub_
+STUBCOPY_RELOC-$(CONFIG_LOONGARCH)	:= R_LARCH_MARK_LA
+
+$(obj)/%.stub.o: $(obj)/%.o FORCE
+	$(call if_changed,stubcopy)
+
+#
+# Strip debug sections and some other sections that may legally contain
+# absolute relocations, so that we can inspect the remaining sections for
+# such relocations. If none are found, regenerate the output object, but
+# this time, use objcopy and leave all sections in place.
+#
+quiet_cmd_stubcopy = STUBCPY $@
+      cmd_stubcopy =							\
+	$(STRIP) --strip-debug -o $@ $<;				\
+	if $(OBJDUMP) -r $@ | grep $(STUBCOPY_RELOC-y); then		\
+		echo "$@: absolute symbol references not allowed in the EFI stub" >&2; \
+		/bin/false;						\
+	fi;								\
+	$(OBJCOPY) $(STUBCOPY_FLAGS-y) $< $@
diff --git a/drivers/firmware/efi/libstub/Makefile.zboot b/drivers/firmware/efi/libstub/Makefile.zboot
new file mode 100644
index 000000000..3340b385a
--- /dev/null
+++ b/drivers/firmware/efi/libstub/Makefile.zboot
@@ -0,0 +1,49 @@
+# SPDX-License-Identifier: GPL-2.0
+
+# to be include'd by arch/$(ARCH)/boot/Makefile after setting
+# EFI_ZBOOT_PAYLOAD, EFI_ZBOOT_BFD_TARGET and EFI_ZBOOT_MACH_TYPE
+
+comp-type-$(CONFIG_KERNEL_GZIP)		:= gzip
+comp-type-$(CONFIG_KERNEL_LZ4)		:= lz4
+comp-type-$(CONFIG_KERNEL_LZMA)		:= lzma
+comp-type-$(CONFIG_KERNEL_LZO)		:= lzo
+comp-type-$(CONFIG_KERNEL_XZ)		:= xzkern
+comp-type-$(CONFIG_KERNEL_ZSTD)		:= zstd22
+
+# in GZIP, the appended le32 carrying the uncompressed size is part of the
+# format, but in other cases, we just append it at the end for convenience,
+# causing the original tools to complain when checking image integrity.
+# So disregard it when calculating the payload size in the zimage header.
+zboot-method-y				:= $(comp-type-y)_with_size
+zboot-size-len-y			:= 4
+
+zboot-method-$(CONFIG_KERNEL_GZIP)	:= gzip
+zboot-size-len-$(CONFIG_KERNEL_GZIP)	:= 0
+
+$(obj)/vmlinuz: $(obj)/$(EFI_ZBOOT_PAYLOAD) FORCE
+	$(call if_changed,$(zboot-method-y))
+
+OBJCOPYFLAGS_vmlinuz.o := -I binary -O $(EFI_ZBOOT_BFD_TARGET) \
+			  --rename-section .data=.gzdata,load,alloc,readonly,contents
+$(obj)/vmlinuz.o: $(obj)/vmlinuz FORCE
+	$(call if_changed,objcopy)
+
+AFLAGS_zboot-header.o += -DMACHINE_TYPE=IMAGE_FILE_MACHINE_$(EFI_ZBOOT_MACH_TYPE) \
+			 -DZBOOT_EFI_PATH="\"$(realpath $(obj)/vmlinuz.efi.elf)\"" \
+			 -DZBOOT_SIZE_LEN=$(zboot-size-len-y) \
+			 -DCOMP_TYPE="\"$(comp-type-y)\""
+
+$(obj)/zboot-header.o: $(srctree)/drivers/firmware/efi/libstub/zboot-header.S FORCE
+	$(call if_changed_rule,as_o_S)
+
+ZBOOT_DEPS := $(obj)/zboot-header.o $(objtree)/drivers/firmware/efi/libstub/lib.a
+
+LDFLAGS_vmlinuz.efi.elf := -T $(srctree)/drivers/firmware/efi/libstub/zboot.lds
+$(obj)/vmlinuz.efi.elf: $(obj)/vmlinuz.o $(ZBOOT_DEPS) FORCE
+	$(call if_changed,ld)
+
+OBJCOPYFLAGS_vmlinuz.efi := -O binary
+$(obj)/vmlinuz.efi: $(obj)/vmlinuz.efi.elf FORCE
+	$(call if_changed,objcopy)
+
+targets += zboot-header.o vmlinuz vmlinuz.o vmlinuz.efi.elf vmlinuz.efi
diff --git a/drivers/firmware/efi/libstub/alignedmem.c b/drivers/firmware/efi/libstub/alignedmem.c
new file mode 100644
index 000000000..1de9878dd
--- /dev/null
+++ b/drivers/firmware/efi/libstub/alignedmem.c
@@ -0,0 +1,57 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/efi.h>
+#include <asm/efi.h>
+
+#include "efistub.h"
+
+/**
+ * efi_allocate_pages_aligned() - Allocate memory pages
+ * @size:	minimum number of bytes to allocate
+ * @addr:	On return the address of the first allocated page. The first
+ *		allocated page has alignment EFI_ALLOC_ALIGN which is an
+ *		architecture dependent multiple of the page size.
+ * @max:	the address that the last allocated memory page shall not
+ *		exceed
+ * @align:	minimum alignment of the base of the allocation
+ *
+ * Allocate pages as EFI_LOADER_DATA. The allocated pages are aligned according
+ * to @align, which should be >= EFI_ALLOC_ALIGN. The last allocated page will
+ * not exceed the address given by @max.
+ *
+ * Return:	status code
+ */
+efi_status_t efi_allocate_pages_aligned(unsigned long size, unsigned long *addr,
+					unsigned long max, unsigned long align)
+{
+	efi_physical_addr_t alloc_addr;
+	efi_status_t status;
+	int slack;
+
+	if (align < EFI_ALLOC_ALIGN)
+		align = EFI_ALLOC_ALIGN;
+
+	alloc_addr = ALIGN_DOWN(max + 1, align) - 1;
+	size = round_up(size, EFI_ALLOC_ALIGN);
+	slack = align / EFI_PAGE_SIZE - 1;
+
+	status = efi_bs_call(allocate_pages, EFI_ALLOCATE_MAX_ADDRESS,
+			     EFI_LOADER_DATA, size / EFI_PAGE_SIZE + slack,
+			     &alloc_addr);
+	if (status != EFI_SUCCESS)
+		return status;
+
+	*addr = ALIGN((unsigned long)alloc_addr, align);
+
+	if (slack > 0) {
+		int l = (alloc_addr & (align - 1)) / EFI_PAGE_SIZE;
+
+		if (l) {
+			efi_bs_call(free_pages, alloc_addr, slack - l + 1);
+			slack = l - 1;
+		}
+		if (slack)
+			efi_bs_call(free_pages, *addr + size, slack);
+	}
+	return EFI_SUCCESS;
+}
diff --git a/drivers/firmware/efi/libstub/arm32-stub.c b/drivers/firmware/efi/libstub/arm32-stub.c
new file mode 100644
index 000000000..0131e3aaa
--- /dev/null
+++ b/drivers/firmware/efi/libstub/arm32-stub.c
@@ -0,0 +1,171 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2013 Linaro Ltd;  <roy.franz@linaro.org>
+ */
+#include <linux/efi.h>
+#include <asm/efi.h>
+
+#include "efistub.h"
+
+static efi_guid_t cpu_state_guid = LINUX_EFI_ARM_CPU_STATE_TABLE_GUID;
+
+struct efi_arm_entry_state *efi_entry_state;
+
+static void get_cpu_state(u32 *cpsr, u32 *sctlr)
+{
+	asm("mrs %0, cpsr" : "=r"(*cpsr));
+	if ((*cpsr & MODE_MASK) == HYP_MODE)
+		asm("mrc p15, 4, %0, c1, c0, 0" : "=r"(*sctlr));
+	else
+		asm("mrc p15, 0, %0, c1, c0, 0" : "=r"(*sctlr));
+}
+
+efi_status_t check_platform_features(void)
+{
+	efi_status_t status;
+	u32 cpsr, sctlr;
+	int block;
+
+	get_cpu_state(&cpsr, &sctlr);
+
+	efi_info("Entering in %s mode with MMU %sabled\n",
+		 ((cpsr & MODE_MASK) == HYP_MODE) ? "HYP" : "SVC",
+		 (sctlr & 1) ? "en" : "dis");
+
+	status = efi_bs_call(allocate_pool, EFI_LOADER_DATA,
+			     sizeof(*efi_entry_state),
+			     (void **)&efi_entry_state);
+	if (status != EFI_SUCCESS) {
+		efi_err("allocate_pool() failed\n");
+		return status;
+	}
+
+	efi_entry_state->cpsr_before_ebs = cpsr;
+	efi_entry_state->sctlr_before_ebs = sctlr;
+
+	status = efi_bs_call(install_configuration_table, &cpu_state_guid,
+			     efi_entry_state);
+	if (status != EFI_SUCCESS) {
+		efi_err("install_configuration_table() failed\n");
+		goto free_state;
+	}
+
+	/* non-LPAE kernels can run anywhere */
+	if (!IS_ENABLED(CONFIG_ARM_LPAE))
+		return EFI_SUCCESS;
+
+	/* LPAE kernels need compatible hardware */
+	block = cpuid_feature_extract(CPUID_EXT_MMFR0, 0);
+	if (block < 5) {
+		efi_err("This LPAE kernel is not supported by your CPU\n");
+		status = EFI_UNSUPPORTED;
+		goto drop_table;
+	}
+	return EFI_SUCCESS;
+
+drop_table:
+	efi_bs_call(install_configuration_table, &cpu_state_guid, NULL);
+free_state:
+	efi_bs_call(free_pool, efi_entry_state);
+	return status;
+}
+
+void efi_handle_post_ebs_state(void)
+{
+	get_cpu_state(&efi_entry_state->cpsr_after_ebs,
+		      &efi_entry_state->sctlr_after_ebs);
+}
+
+static efi_guid_t screen_info_guid = LINUX_EFI_ARM_SCREEN_INFO_TABLE_GUID;
+
+struct screen_info *alloc_screen_info(void)
+{
+	struct screen_info *si;
+	efi_status_t status;
+
+	/*
+	 * Unlike on arm64, where we can directly fill out the screen_info
+	 * structure from the stub, we need to allocate a buffer to hold
+	 * its contents while we hand over to the kernel proper from the
+	 * decompressor.
+	 */
+	status = efi_bs_call(allocate_pool, EFI_RUNTIME_SERVICES_DATA,
+			     sizeof(*si), (void **)&si);
+
+	if (status != EFI_SUCCESS)
+		return NULL;
+
+	status = efi_bs_call(install_configuration_table,
+			     &screen_info_guid, si);
+	if (status == EFI_SUCCESS)
+		return si;
+
+	efi_bs_call(free_pool, si);
+	return NULL;
+}
+
+void free_screen_info(struct screen_info *si)
+{
+	if (!si)
+		return;
+
+	efi_bs_call(install_configuration_table, &screen_info_guid, NULL);
+	efi_bs_call(free_pool, si);
+}
+
+efi_status_t handle_kernel_image(unsigned long *image_addr,
+				 unsigned long *image_size,
+				 unsigned long *reserve_addr,
+				 unsigned long *reserve_size,
+				 efi_loaded_image_t *image,
+				 efi_handle_t image_handle)
+{
+	const int slack = TEXT_OFFSET - 5 * PAGE_SIZE;
+	int alloc_size = MAX_UNCOMP_KERNEL_SIZE + EFI_PHYS_ALIGN;
+	unsigned long alloc_base, kernel_base;
+	efi_status_t status;
+
+	/*
+	 * Allocate space for the decompressed kernel as low as possible.
+	 * The region should be 16 MiB aligned, but the first 'slack' bytes
+	 * are not used by Linux, so we allow those to be occupied by the
+	 * firmware.
+	 */
+	status = efi_low_alloc_above(alloc_size, EFI_PAGE_SIZE, &alloc_base, 0x0);
+	if (status != EFI_SUCCESS) {
+		efi_err("Unable to allocate memory for uncompressed kernel.\n");
+		return status;
+	}
+
+	if ((alloc_base % EFI_PHYS_ALIGN) > slack) {
+		/*
+		 * More than 'slack' bytes are already occupied at the base of
+		 * the allocation, so we need to advance to the next 16 MiB block.
+		 */
+		kernel_base = round_up(alloc_base, EFI_PHYS_ALIGN);
+		efi_info("Free memory starts at 0x%lx, setting kernel_base to 0x%lx\n",
+			 alloc_base, kernel_base);
+	} else {
+		kernel_base = round_down(alloc_base, EFI_PHYS_ALIGN);
+	}
+
+	*reserve_addr = kernel_base + slack;
+	*reserve_size = MAX_UNCOMP_KERNEL_SIZE;
+
+	/* now free the parts that we will not use */
+	if (*reserve_addr > alloc_base) {
+		efi_bs_call(free_pages, alloc_base,
+			    (*reserve_addr - alloc_base) / EFI_PAGE_SIZE);
+		alloc_size -= *reserve_addr - alloc_base;
+	}
+	efi_bs_call(free_pages, *reserve_addr + MAX_UNCOMP_KERNEL_SIZE,
+		    (alloc_size - MAX_UNCOMP_KERNEL_SIZE) / EFI_PAGE_SIZE);
+
+	*image_addr = kernel_base + TEXT_OFFSET;
+	*image_size = 0;
+
+	efi_debug("image addr == 0x%lx, reserve_addr == 0x%lx\n",
+		  *image_addr, *reserve_addr);
+
+	return EFI_SUCCESS;
+}
diff --git a/drivers/firmware/efi/libstub/arm64-stub.c b/drivers/firmware/efi/libstub/arm64-stub.c
new file mode 100644
index 000000000..e2f90566b
--- /dev/null
+++ b/drivers/firmware/efi/libstub/arm64-stub.c
@@ -0,0 +1,217 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2013, 2014 Linaro Ltd;  <roy.franz@linaro.org>
+ *
+ * This file implements the EFI boot stub for the arm64 kernel.
+ * Adapted from ARM version by Mark Salter <msalter@redhat.com>
+ */
+
+
+#include <linux/efi.h>
+#include <asm/efi.h>
+#include <asm/memory.h>
+#include <asm/sections.h>
+#include <asm/sysreg.h>
+
+#include "efistub.h"
+
+static bool system_needs_vamap(void)
+{
+	const struct efi_smbios_type4_record *record;
+	const u32 __aligned(1) *socid;
+	const u8 *version;
+
+	/*
+	 * Ampere eMAG, Altra, and Altra Max machines crash in SetTime() if
+	 * SetVirtualAddressMap() has not been called prior. Most Altra systems
+	 * can be identified by the SMCCC soc ID, which is conveniently exposed
+	 * via the type 4 SMBIOS records. Otherwise, test the processor version
+	 * field. eMAG systems all appear to have the processor version field
+	 * set to "eMAG".
+	 */
+	record = (struct efi_smbios_type4_record *)efi_get_smbios_record(4);
+	if (!record)
+		return false;
+
+	socid = (u32 *)record->processor_id;
+	switch (*socid & 0xffff000f) {
+		static char const altra[] = "Ampere(TM) Altra(TM) Processor";
+		static char const emag[] = "eMAG";
+
+	default:
+		version = efi_get_smbios_string(&record->header, 4,
+						processor_version);
+		if (!version || (strncmp(version, altra, sizeof(altra) - 1) &&
+				 strncmp(version, emag, sizeof(emag) - 1)))
+			break;
+
+		fallthrough;
+
+	case 0x0a160001:	// Altra
+	case 0x0a160002:	// Altra Max
+		efi_warn("Working around broken SetVirtualAddressMap()\n");
+		return true;
+	}
+
+	return false;
+}
+
+efi_status_t check_platform_features(void)
+{
+	u64 tg;
+
+	/*
+	 * If we have 48 bits of VA space for TTBR0 mappings, we can map the
+	 * UEFI runtime regions 1:1 and so calling SetVirtualAddressMap() is
+	 * unnecessary.
+	 */
+	if (VA_BITS_MIN >= 48 && !system_needs_vamap())
+		efi_novamap = true;
+
+	/* UEFI mandates support for 4 KB granularity, no need to check */
+	if (IS_ENABLED(CONFIG_ARM64_4K_PAGES))
+		return EFI_SUCCESS;
+
+	tg = (read_cpuid(ID_AA64MMFR0_EL1) >> ID_AA64MMFR0_EL1_TGRAN_SHIFT) & 0xf;
+	if (tg < ID_AA64MMFR0_EL1_TGRAN_SUPPORTED_MIN || tg > ID_AA64MMFR0_EL1_TGRAN_SUPPORTED_MAX) {
+		if (IS_ENABLED(CONFIG_ARM64_64K_PAGES))
+			efi_err("This 64 KB granular kernel is not supported by your CPU\n");
+		else
+			efi_err("This 16 KB granular kernel is not supported by your CPU\n");
+		return EFI_UNSUPPORTED;
+	}
+	return EFI_SUCCESS;
+}
+
+/*
+ * Distro versions of GRUB may ignore the BSS allocation entirely (i.e., fail
+ * to provide space, and fail to zero it). Check for this condition by double
+ * checking that the first and the last byte of the image are covered by the
+ * same EFI memory map entry.
+ */
+static bool check_image_region(u64 base, u64 size)
+{
+	struct efi_boot_memmap *map;
+	efi_status_t status;
+	bool ret = false;
+	int map_offset;
+
+	status = efi_get_memory_map(&map, false);
+	if (status != EFI_SUCCESS)
+		return false;
+
+	for (map_offset = 0; map_offset < map->map_size; map_offset += map->desc_size) {
+		efi_memory_desc_t *md = (void *)map->map + map_offset;
+		u64 end = md->phys_addr + md->num_pages * EFI_PAGE_SIZE;
+
+		/*
+		 * Find the region that covers base, and return whether
+		 * it covers base+size bytes.
+		 */
+		if (base >= md->phys_addr && base < end) {
+			ret = (base + size) <= end;
+			break;
+		}
+	}
+
+	efi_bs_call(free_pool, map);
+
+	return ret;
+}
+
+efi_status_t handle_kernel_image(unsigned long *image_addr,
+				 unsigned long *image_size,
+				 unsigned long *reserve_addr,
+				 unsigned long *reserve_size,
+				 efi_loaded_image_t *image,
+				 efi_handle_t image_handle)
+{
+	efi_status_t status;
+	unsigned long kernel_size, kernel_memsize = 0;
+	u32 phys_seed = 0;
+
+	/*
+	 * Although relocatable kernels can fix up the misalignment with
+	 * respect to MIN_KIMG_ALIGN, the resulting virtual text addresses are
+	 * subtly out of sync with those recorded in the vmlinux when kaslr is
+	 * disabled but the image required relocation anyway. Therefore retain
+	 * 2M alignment if KASLR was explicitly disabled, even if it was not
+	 * going to be activated to begin with.
+	 */
+	u64 min_kimg_align = efi_nokaslr ? MIN_KIMG_ALIGN : EFI_KIMG_ALIGN;
+
+	if (IS_ENABLED(CONFIG_RANDOMIZE_BASE)) {
+		efi_guid_t li_fixed_proto = LINUX_EFI_LOADED_IMAGE_FIXED_GUID;
+		void *p;
+
+		if (efi_nokaslr) {
+			efi_info("KASLR disabled on kernel command line\n");
+		} else if (efi_bs_call(handle_protocol, image_handle,
+				       &li_fixed_proto, &p) == EFI_SUCCESS) {
+			efi_info("Image placement fixed by loader\n");
+		} else {
+			status = efi_get_random_bytes(sizeof(phys_seed),
+						      (u8 *)&phys_seed);
+			if (status == EFI_NOT_FOUND) {
+				efi_info("EFI_RNG_PROTOCOL unavailable\n");
+				efi_nokaslr = true;
+			} else if (status != EFI_SUCCESS) {
+				efi_err("efi_get_random_bytes() failed (0x%lx)\n",
+					status);
+				efi_nokaslr = true;
+			}
+		}
+	}
+
+	if (image->image_base != _text)
+		efi_err("FIRMWARE BUG: efi_loaded_image_t::image_base has bogus value\n");
+
+	if (!IS_ALIGNED((u64)_text, SEGMENT_ALIGN))
+		efi_err("FIRMWARE BUG: kernel image not aligned on %dk boundary\n",
+			SEGMENT_ALIGN >> 10);
+
+	kernel_size = _edata - _text;
+	kernel_memsize = kernel_size + (_end - _edata);
+	*reserve_size = kernel_memsize;
+
+	if (IS_ENABLED(CONFIG_RANDOMIZE_BASE) && phys_seed != 0) {
+		/*
+		 * If KASLR is enabled, and we have some randomness available,
+		 * locate the kernel at a randomized offset in physical memory.
+		 */
+		status = efi_random_alloc(*reserve_size, min_kimg_align,
+					  reserve_addr, phys_seed);
+		if (status != EFI_SUCCESS)
+			efi_warn("efi_random_alloc() failed: 0x%lx\n", status);
+	} else {
+		status = EFI_OUT_OF_RESOURCES;
+	}
+
+	if (status != EFI_SUCCESS) {
+		if (!check_image_region((u64)_text, kernel_memsize)) {
+			efi_err("FIRMWARE BUG: Image BSS overlaps adjacent EFI memory region\n");
+		} else if (IS_ALIGNED((u64)_text, min_kimg_align)) {
+			/*
+			 * Just execute from wherever we were loaded by the
+			 * UEFI PE/COFF loader if the alignment is suitable.
+			 */
+			*image_addr = (u64)_text;
+			*reserve_size = 0;
+			return EFI_SUCCESS;
+		}
+
+		status = efi_allocate_pages_aligned(*reserve_size, reserve_addr,
+						    ULONG_MAX, min_kimg_align);
+
+		if (status != EFI_SUCCESS) {
+			efi_err("Failed to relocate kernel\n");
+			*reserve_size = 0;
+			return status;
+		}
+	}
+
+	*image_addr = *reserve_addr;
+	memcpy((void *)*image_addr, _text, kernel_size);
+
+	return EFI_SUCCESS;
+}
diff --git a/drivers/firmware/efi/libstub/efi-stub-helper.c b/drivers/firmware/efi/libstub/efi-stub-helper.c
new file mode 100644
index 000000000..3d9b2469a
--- /dev/null
+++ b/drivers/firmware/efi/libstub/efi-stub-helper.c
@@ -0,0 +1,797 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Helper functions used by the EFI stub on multiple
+ * architectures. This should be #included by the EFI stub
+ * implementation files.
+ *
+ * Copyright 2011 Intel Corporation; author Matt Fleming
+ */
+
+#include <linux/stdarg.h>
+
+#include <linux/ctype.h>
+#include <linux/efi.h>
+#include <linux/kernel.h>
+#include <linux/printk.h> /* For CONSOLE_LOGLEVEL_* */
+#include <asm/efi.h>
+#include <asm/setup.h>
+
+#include "efistub.h"
+
+bool efi_nochunk;
+bool efi_nokaslr = !IS_ENABLED(CONFIG_RANDOMIZE_BASE);
+int efi_loglevel = CONSOLE_LOGLEVEL_DEFAULT;
+bool efi_novamap;
+
+static bool efi_noinitrd;
+static bool efi_nosoftreserve;
+static bool efi_disable_pci_dma = IS_ENABLED(CONFIG_EFI_DISABLE_PCI_DMA);
+
+bool __pure __efi_soft_reserve_enabled(void)
+{
+	return !efi_nosoftreserve;
+}
+
+/**
+ * efi_char16_puts() - Write a UCS-2 encoded string to the console
+ * @str:	UCS-2 encoded string
+ */
+void efi_char16_puts(efi_char16_t *str)
+{
+	efi_call_proto(efi_table_attr(efi_system_table, con_out),
+		       output_string, str);
+}
+
+static
+u32 utf8_to_utf32(const u8 **s8)
+{
+	u32 c32;
+	u8 c0, cx;
+	size_t clen, i;
+
+	c0 = cx = *(*s8)++;
+	/*
+	 * The position of the most-significant 0 bit gives us the length of
+	 * a multi-octet encoding.
+	 */
+	for (clen = 0; cx & 0x80; ++clen)
+		cx <<= 1;
+	/*
+	 * If the 0 bit is in position 8, this is a valid single-octet
+	 * encoding. If the 0 bit is in position 7 or positions 1-3, the
+	 * encoding is invalid.
+	 * In either case, we just return the first octet.
+	 */
+	if (clen < 2 || clen > 4)
+		return c0;
+	/* Get the bits from the first octet. */
+	c32 = cx >> clen--;
+	for (i = 0; i < clen; ++i) {
+		/* Trailing octets must have 10 in most significant bits. */
+		cx = (*s8)[i] ^ 0x80;
+		if (cx & 0xc0)
+			return c0;
+		c32 = (c32 << 6) | cx;
+	}
+	/*
+	 * Check for validity:
+	 * - The character must be in the Unicode range.
+	 * - It must not be a surrogate.
+	 * - It must be encoded using the correct number of octets.
+	 */
+	if (c32 > 0x10ffff ||
+	    (c32 & 0xf800) == 0xd800 ||
+	    clen != (c32 >= 0x80) + (c32 >= 0x800) + (c32 >= 0x10000))
+		return c0;
+	*s8 += clen;
+	return c32;
+}
+
+/**
+ * efi_puts() - Write a UTF-8 encoded string to the console
+ * @str:	UTF-8 encoded string
+ */
+void efi_puts(const char *str)
+{
+	efi_char16_t buf[128];
+	size_t pos = 0, lim = ARRAY_SIZE(buf);
+	const u8 *s8 = (const u8 *)str;
+	u32 c32;
+
+	while (*s8) {
+		if (*s8 == '\n')
+			buf[pos++] = L'\r';
+		c32 = utf8_to_utf32(&s8);
+		if (c32 < 0x10000) {
+			/* Characters in plane 0 use a single word. */
+			buf[pos++] = c32;
+		} else {
+			/*
+			 * Characters in other planes encode into a surrogate
+			 * pair.
+			 */
+			buf[pos++] = (0xd800 - (0x10000 >> 10)) + (c32 >> 10);
+			buf[pos++] = 0xdc00 + (c32 & 0x3ff);
+		}
+		if (*s8 == '\0' || pos >= lim - 2) {
+			buf[pos] = L'\0';
+			efi_char16_puts(buf);
+			pos = 0;
+		}
+	}
+}
+
+/**
+ * efi_printk() - Print a kernel message
+ * @fmt:	format string
+ *
+ * The first letter of the format string is used to determine the logging level
+ * of the message. If the level is less then the current EFI logging level, the
+ * message is suppressed. The message will be truncated to 255 bytes.
+ *
+ * Return:	number of printed characters
+ */
+int efi_printk(const char *fmt, ...)
+{
+	char printf_buf[256];
+	va_list args;
+	int printed;
+	int loglevel = printk_get_level(fmt);
+
+	switch (loglevel) {
+	case '0' ... '9':
+		loglevel -= '0';
+		break;
+	default:
+		/*
+		 * Use loglevel -1 for cases where we just want to print to
+		 * the screen.
+		 */
+		loglevel = -1;
+		break;
+	}
+
+	if (loglevel >= efi_loglevel)
+		return 0;
+
+	if (loglevel >= 0)
+		efi_puts("EFI stub: ");
+
+	fmt = printk_skip_level(fmt);
+
+	va_start(args, fmt);
+	printed = vsnprintf(printf_buf, sizeof(printf_buf), fmt, args);
+	va_end(args);
+
+	efi_puts(printf_buf);
+	if (printed >= sizeof(printf_buf)) {
+		efi_puts("[Message truncated]\n");
+		return -1;
+	}
+
+	return printed;
+}
+
+/**
+ * efi_parse_options() - Parse EFI command line options
+ * @cmdline:	kernel command line
+ *
+ * Parse the ASCII string @cmdline for EFI options, denoted by the efi=
+ * option, e.g. efi=nochunk.
+ *
+ * It should be noted that efi= is parsed in two very different
+ * environments, first in the early boot environment of the EFI boot
+ * stub, and subsequently during the kernel boot.
+ *
+ * Return:	status code
+ */
+efi_status_t efi_parse_options(char const *cmdline)
+{
+	size_t len;
+	efi_status_t status;
+	char *str, *buf;
+
+	if (!cmdline)
+		return EFI_SUCCESS;
+
+	len = strnlen(cmdline, COMMAND_LINE_SIZE - 1) + 1;
+	status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, len, (void **)&buf);
+	if (status != EFI_SUCCESS)
+		return status;
+
+	memcpy(buf, cmdline, len - 1);
+	buf[len - 1] = '\0';
+	str = skip_spaces(buf);
+
+	while (*str) {
+		char *param, *val;
+
+		str = next_arg(str, &param, &val);
+		if (!val && !strcmp(param, "--"))
+			break;
+
+		if (!strcmp(param, "nokaslr")) {
+			efi_nokaslr = true;
+		} else if (!strcmp(param, "quiet")) {
+			efi_loglevel = CONSOLE_LOGLEVEL_QUIET;
+		} else if (!strcmp(param, "noinitrd")) {
+			efi_noinitrd = true;
+		} else if (!strcmp(param, "efi") && val) {
+			efi_nochunk = parse_option_str(val, "nochunk");
+			efi_novamap |= parse_option_str(val, "novamap");
+
+			efi_nosoftreserve = IS_ENABLED(CONFIG_EFI_SOFT_RESERVE) &&
+					    parse_option_str(val, "nosoftreserve");
+
+			if (parse_option_str(val, "disable_early_pci_dma"))
+				efi_disable_pci_dma = true;
+			if (parse_option_str(val, "no_disable_early_pci_dma"))
+				efi_disable_pci_dma = false;
+			if (parse_option_str(val, "debug"))
+				efi_loglevel = CONSOLE_LOGLEVEL_DEBUG;
+		} else if (!strcmp(param, "video") &&
+			   val && strstarts(val, "efifb:")) {
+			efi_parse_option_graphics(val + strlen("efifb:"));
+		}
+	}
+	efi_bs_call(free_pool, buf);
+	return EFI_SUCCESS;
+}
+
+/*
+ * The EFI_LOAD_OPTION descriptor has the following layout:
+ *	u32 Attributes;
+ *	u16 FilePathListLength;
+ *	u16 Description[];
+ *	efi_device_path_protocol_t FilePathList[];
+ *	u8 OptionalData[];
+ *
+ * This function validates and unpacks the variable-size data fields.
+ */
+static
+bool efi_load_option_unpack(efi_load_option_unpacked_t *dest,
+			    const efi_load_option_t *src, size_t size)
+{
+	const void *pos;
+	u16 c;
+	efi_device_path_protocol_t header;
+	const efi_char16_t *description;
+	const efi_device_path_protocol_t *file_path_list;
+
+	if (size < offsetof(efi_load_option_t, variable_data))
+		return false;
+	pos = src->variable_data;
+	size -= offsetof(efi_load_option_t, variable_data);
+
+	if ((src->attributes & ~EFI_LOAD_OPTION_MASK) != 0)
+		return false;
+
+	/* Scan description. */
+	description = pos;
+	do {
+		if (size < sizeof(c))
+			return false;
+		c = *(const u16 *)pos;
+		pos += sizeof(c);
+		size -= sizeof(c);
+	} while (c != L'\0');
+
+	/* Scan file_path_list. */
+	file_path_list = pos;
+	do {
+		if (size < sizeof(header))
+			return false;
+		header = *(const efi_device_path_protocol_t *)pos;
+		if (header.length < sizeof(header))
+			return false;
+		if (size < header.length)
+			return false;
+		pos += header.length;
+		size -= header.length;
+	} while ((header.type != EFI_DEV_END_PATH && header.type != EFI_DEV_END_PATH2) ||
+		 (header.sub_type != EFI_DEV_END_ENTIRE));
+	if (pos != (const void *)file_path_list + src->file_path_list_length)
+		return false;
+
+	dest->attributes = src->attributes;
+	dest->file_path_list_length = src->file_path_list_length;
+	dest->description = description;
+	dest->file_path_list = file_path_list;
+	dest->optional_data_size = size;
+	dest->optional_data = size ? pos : NULL;
+
+	return true;
+}
+
+/*
+ * At least some versions of Dell firmware pass the entire contents of the
+ * Boot#### variable, i.e. the EFI_LOAD_OPTION descriptor, rather than just the
+ * OptionalData field.
+ *
+ * Detect this case and extract OptionalData.
+ */
+void efi_apply_loadoptions_quirk(const void **load_options, u32 *load_options_size)
+{
+	const efi_load_option_t *load_option = *load_options;
+	efi_load_option_unpacked_t load_option_unpacked;
+
+	if (!IS_ENABLED(CONFIG_X86))
+		return;
+	if (!load_option)
+		return;
+	if (*load_options_size < sizeof(*load_option))
+		return;
+	if ((load_option->attributes & ~EFI_LOAD_OPTION_BOOT_MASK) != 0)
+		return;
+
+	if (!efi_load_option_unpack(&load_option_unpacked, load_option, *load_options_size))
+		return;
+
+	efi_warn_once(FW_BUG "LoadOptions is an EFI_LOAD_OPTION descriptor\n");
+	efi_warn_once(FW_BUG "Using OptionalData as a workaround\n");
+
+	*load_options = load_option_unpacked.optional_data;
+	*load_options_size = load_option_unpacked.optional_data_size;
+}
+
+enum efistub_event {
+	EFISTUB_EVT_INITRD,
+	EFISTUB_EVT_LOAD_OPTIONS,
+	EFISTUB_EVT_COUNT,
+};
+
+#define STR_WITH_SIZE(s)	sizeof(s), s
+
+static const struct {
+	u32		pcr_index;
+	u32		event_id;
+	u32		event_data_len;
+	u8		event_data[52];
+} events[] = {
+	[EFISTUB_EVT_INITRD] = {
+		9,
+		INITRD_EVENT_TAG_ID,
+		STR_WITH_SIZE("Linux initrd")
+	},
+	[EFISTUB_EVT_LOAD_OPTIONS] = {
+		9,
+		LOAD_OPTIONS_EVENT_TAG_ID,
+		STR_WITH_SIZE("LOADED_IMAGE::LoadOptions")
+	},
+};
+
+static efi_status_t efi_measure_tagged_event(unsigned long load_addr,
+					     unsigned long load_size,
+					     enum efistub_event event)
+{
+	efi_guid_t tcg2_guid = EFI_TCG2_PROTOCOL_GUID;
+	efi_tcg2_protocol_t *tcg2 = NULL;
+	efi_status_t status;
+
+	efi_bs_call(locate_protocol, &tcg2_guid, NULL, (void **)&tcg2);
+	if (tcg2) {
+		struct efi_measured_event {
+			efi_tcg2_event_t	event_data;
+			efi_tcg2_tagged_event_t tagged_event;
+			u8			tagged_event_data[];
+		} *evt;
+		int size = sizeof(*evt) + events[event].event_data_len;
+
+		status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, size,
+				     (void **)&evt);
+		if (status != EFI_SUCCESS)
+			goto fail;
+
+		evt->event_data = (struct efi_tcg2_event){
+			.event_size			= size,
+			.event_header.header_size	= sizeof(evt->event_data.event_header),
+			.event_header.header_version	= EFI_TCG2_EVENT_HEADER_VERSION,
+			.event_header.pcr_index		= events[event].pcr_index,
+			.event_header.event_type	= EV_EVENT_TAG,
+		};
+
+		evt->tagged_event = (struct efi_tcg2_tagged_event){
+			.tagged_event_id		= events[event].event_id,
+			.tagged_event_data_size		= events[event].event_data_len,
+		};
+
+		memcpy(evt->tagged_event_data, events[event].event_data,
+		       events[event].event_data_len);
+
+		status = efi_call_proto(tcg2, hash_log_extend_event, 0,
+					load_addr, load_size, &evt->event_data);
+		efi_bs_call(free_pool, evt);
+
+		if (status != EFI_SUCCESS)
+			goto fail;
+		return EFI_SUCCESS;
+	}
+
+	return EFI_UNSUPPORTED;
+fail:
+	efi_warn("Failed to measure data for event %d: 0x%lx\n", event, status);
+	return status;
+}
+
+/*
+ * Convert the unicode UEFI command line to ASCII to pass to kernel.
+ * Size of memory allocated return in *cmd_line_len.
+ * Returns NULL on error.
+ */
+char *efi_convert_cmdline(efi_loaded_image_t *image, int *cmd_line_len)
+{
+	const efi_char16_t *options = efi_table_attr(image, load_options);
+	u32 options_size = efi_table_attr(image, load_options_size);
+	int options_bytes = 0, safe_options_bytes = 0;  /* UTF-8 bytes */
+	unsigned long cmdline_addr = 0;
+	const efi_char16_t *s2;
+	bool in_quote = false;
+	efi_status_t status;
+	u32 options_chars;
+
+	if (options_size > 0)
+		efi_measure_tagged_event((unsigned long)options, options_size,
+					 EFISTUB_EVT_LOAD_OPTIONS);
+
+	efi_apply_loadoptions_quirk((const void **)&options, &options_size);
+	options_chars = options_size / sizeof(efi_char16_t);
+
+	if (options) {
+		s2 = options;
+		while (options_bytes < COMMAND_LINE_SIZE && options_chars--) {
+			efi_char16_t c = *s2++;
+
+			if (c < 0x80) {
+				if (c == L'\0' || c == L'\n')
+					break;
+				if (c == L'"')
+					in_quote = !in_quote;
+				else if (!in_quote && isspace((char)c))
+					safe_options_bytes = options_bytes;
+
+				options_bytes++;
+				continue;
+			}
+
+			/*
+			 * Get the number of UTF-8 bytes corresponding to a
+			 * UTF-16 character.
+			 * The first part handles everything in the BMP.
+			 */
+			options_bytes += 2 + (c >= 0x800);
+			/*
+			 * Add one more byte for valid surrogate pairs. Invalid
+			 * surrogates will be replaced with 0xfffd and take up
+			 * only 3 bytes.
+			 */
+			if ((c & 0xfc00) == 0xd800) {
+				/*
+				 * If the very last word is a high surrogate,
+				 * we must ignore it since we can't access the
+				 * low surrogate.
+				 */
+				if (!options_chars) {
+					options_bytes -= 3;
+				} else if ((*s2 & 0xfc00) == 0xdc00) {
+					options_bytes++;
+					options_chars--;
+					s2++;
+				}
+			}
+		}
+		if (options_bytes >= COMMAND_LINE_SIZE) {
+			options_bytes = safe_options_bytes;
+			efi_err("Command line is too long: truncated to %d bytes\n",
+				options_bytes);
+		}
+	}
+
+	options_bytes++;	/* NUL termination */
+
+	status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, options_bytes,
+			     (void **)&cmdline_addr);
+	if (status != EFI_SUCCESS)
+		return NULL;
+
+	snprintf((char *)cmdline_addr, options_bytes, "%.*ls",
+		 options_bytes - 1, options);
+
+	*cmd_line_len = options_bytes;
+	return (char *)cmdline_addr;
+}
+
+/**
+ * efi_exit_boot_services() - Exit boot services
+ * @handle:	handle of the exiting image
+ * @priv:	argument to be passed to @priv_func
+ * @priv_func:	function to process the memory map before exiting boot services
+ *
+ * Handle calling ExitBootServices according to the requirements set out by the
+ * spec.  Obtains the current memory map, and returns that info after calling
+ * ExitBootServices.  The client must specify a function to perform any
+ * processing of the memory map data prior to ExitBootServices.  A client
+ * specific structure may be passed to the function via priv.  The client
+ * function may be called multiple times.
+ *
+ * Return:	status code
+ */
+efi_status_t efi_exit_boot_services(void *handle, void *priv,
+				    efi_exit_boot_map_processing priv_func)
+{
+	struct efi_boot_memmap *map;
+	efi_status_t status;
+
+	if (efi_disable_pci_dma)
+		efi_pci_disable_bridge_busmaster();
+
+	status = efi_get_memory_map(&map, true);
+	if (status != EFI_SUCCESS)
+		return status;
+
+	status = priv_func(map, priv);
+	if (status != EFI_SUCCESS) {
+		efi_bs_call(free_pool, map);
+		return status;
+	}
+
+	status = efi_bs_call(exit_boot_services, handle, map->map_key);
+
+	if (status == EFI_INVALID_PARAMETER) {
+		/*
+		 * The memory map changed between efi_get_memory_map() and
+		 * exit_boot_services().  Per the UEFI Spec v2.6, Section 6.4:
+		 * EFI_BOOT_SERVICES.ExitBootServices we need to get the
+		 * updated map, and try again.  The spec implies one retry
+		 * should be sufficent, which is confirmed against the EDK2
+		 * implementation.  Per the spec, we can only invoke
+		 * get_memory_map() and exit_boot_services() - we cannot alloc
+		 * so efi_get_memory_map() cannot be used, and we must reuse
+		 * the buffer.  For all practical purposes, the headroom in the
+		 * buffer should account for any changes in the map so the call
+		 * to get_memory_map() is expected to succeed here.
+		 */
+		map->map_size = map->buff_size;
+		status = efi_bs_call(get_memory_map,
+				     &map->map_size,
+				     &map->map,
+				     &map->map_key,
+				     &map->desc_size,
+				     &map->desc_ver);
+
+		/* exit_boot_services() was called, thus cannot free */
+		if (status != EFI_SUCCESS)
+			return status;
+
+		status = priv_func(map, priv);
+		/* exit_boot_services() was called, thus cannot free */
+		if (status != EFI_SUCCESS)
+			return status;
+
+		status = efi_bs_call(exit_boot_services, handle, map->map_key);
+	}
+
+	return status;
+}
+
+/**
+ * get_efi_config_table() - retrieve UEFI configuration table
+ * @guid:	GUID of the configuration table to be retrieved
+ * Return:	pointer to the configuration table or NULL
+ */
+void *get_efi_config_table(efi_guid_t guid)
+{
+	unsigned long tables = efi_table_attr(efi_system_table, tables);
+	int nr_tables = efi_table_attr(efi_system_table, nr_tables);
+	int i;
+
+	for (i = 0; i < nr_tables; i++) {
+		efi_config_table_t *t = (void *)tables;
+
+		if (efi_guidcmp(t->guid, guid) == 0)
+			return efi_table_attr(t, table);
+
+		tables += efi_is_native() ? sizeof(efi_config_table_t)
+					  : sizeof(efi_config_table_32_t);
+	}
+	return NULL;
+}
+
+/*
+ * The LINUX_EFI_INITRD_MEDIA_GUID vendor media device path below provides a way
+ * for the firmware or bootloader to expose the initrd data directly to the stub
+ * via the trivial LoadFile2 protocol, which is defined in the UEFI spec, and is
+ * very easy to implement. It is a simple Linux initrd specific conduit between
+ * kernel and firmware, allowing us to put the EFI stub (being part of the
+ * kernel) in charge of where and when to load the initrd, while leaving it up
+ * to the firmware to decide whether it needs to expose its filesystem hierarchy
+ * via EFI protocols.
+ */
+static const struct {
+	struct efi_vendor_dev_path	vendor;
+	struct efi_generic_dev_path	end;
+} __packed initrd_dev_path = {
+	{
+		{
+			EFI_DEV_MEDIA,
+			EFI_DEV_MEDIA_VENDOR,
+			sizeof(struct efi_vendor_dev_path),
+		},
+		LINUX_EFI_INITRD_MEDIA_GUID
+	}, {
+		EFI_DEV_END_PATH,
+		EFI_DEV_END_ENTIRE,
+		sizeof(struct efi_generic_dev_path)
+	}
+};
+
+/**
+ * efi_load_initrd_dev_path() - load the initrd from the Linux initrd device path
+ * @load_addr:	pointer to store the address where the initrd was loaded
+ * @load_size:	pointer to store the size of the loaded initrd
+ * @max:	upper limit for the initrd memory allocation
+ *
+ * Return:
+ * * %EFI_SUCCESS if the initrd was loaded successfully, in which
+ *   case @load_addr and @load_size are assigned accordingly
+ * * %EFI_NOT_FOUND if no LoadFile2 protocol exists on the initrd device path
+ * * %EFI_OUT_OF_RESOURCES if memory allocation failed
+ * * %EFI_LOAD_ERROR in all other cases
+ */
+static
+efi_status_t efi_load_initrd_dev_path(struct linux_efi_initrd *initrd,
+				      unsigned long max)
+{
+	efi_guid_t lf2_proto_guid = EFI_LOAD_FILE2_PROTOCOL_GUID;
+	efi_device_path_protocol_t *dp;
+	efi_load_file2_protocol_t *lf2;
+	efi_handle_t handle;
+	efi_status_t status;
+
+	dp = (efi_device_path_protocol_t *)&initrd_dev_path;
+	status = efi_bs_call(locate_device_path, &lf2_proto_guid, &dp, &handle);
+	if (status != EFI_SUCCESS)
+		return status;
+
+	status = efi_bs_call(handle_protocol, handle, &lf2_proto_guid,
+			     (void **)&lf2);
+	if (status != EFI_SUCCESS)
+		return status;
+
+	initrd->size = 0;
+	status = efi_call_proto(lf2, load_file, dp, false, &initrd->size, NULL);
+	if (status != EFI_BUFFER_TOO_SMALL)
+		return EFI_LOAD_ERROR;
+
+	status = efi_allocate_pages(initrd->size, &initrd->base, max);
+	if (status != EFI_SUCCESS)
+		return status;
+
+	status = efi_call_proto(lf2, load_file, dp, false, &initrd->size,
+				(void *)initrd->base);
+	if (status != EFI_SUCCESS) {
+		efi_free(initrd->size, initrd->base);
+		return EFI_LOAD_ERROR;
+	}
+	return EFI_SUCCESS;
+}
+
+static
+efi_status_t efi_load_initrd_cmdline(efi_loaded_image_t *image,
+				     struct linux_efi_initrd *initrd,
+				     unsigned long soft_limit,
+				     unsigned long hard_limit)
+{
+	if (!IS_ENABLED(CONFIG_EFI_GENERIC_STUB_INITRD_CMDLINE_LOADER) ||
+	    (IS_ENABLED(CONFIG_X86) && (!efi_is_native() || image == NULL)))
+		return EFI_UNSUPPORTED;
+
+	return handle_cmdline_files(image, L"initrd=", sizeof(L"initrd=") - 2,
+				    soft_limit, hard_limit,
+				    &initrd->base, &initrd->size);
+}
+
+/**
+ * efi_load_initrd() - Load initial RAM disk
+ * @image:	EFI loaded image protocol
+ * @soft_limit:	preferred address for loading the initrd
+ * @hard_limit:	upper limit address for loading the initrd
+ *
+ * Return:	status code
+ */
+efi_status_t efi_load_initrd(efi_loaded_image_t *image,
+			     unsigned long soft_limit,
+			     unsigned long hard_limit,
+			     const struct linux_efi_initrd **out)
+{
+	efi_guid_t tbl_guid = LINUX_EFI_INITRD_MEDIA_GUID;
+	efi_status_t status = EFI_SUCCESS;
+	struct linux_efi_initrd initrd, *tbl;
+
+	if (!IS_ENABLED(CONFIG_BLK_DEV_INITRD) || efi_noinitrd)
+		return EFI_SUCCESS;
+
+	status = efi_load_initrd_dev_path(&initrd, hard_limit);
+	if (status == EFI_SUCCESS) {
+		efi_info("Loaded initrd from LINUX_EFI_INITRD_MEDIA_GUID device path\n");
+		if (initrd.size > 0 &&
+		    efi_measure_tagged_event(initrd.base, initrd.size,
+					     EFISTUB_EVT_INITRD) == EFI_SUCCESS)
+			efi_info("Measured initrd data into PCR 9\n");
+	} else if (status == EFI_NOT_FOUND) {
+		status = efi_load_initrd_cmdline(image, &initrd, soft_limit,
+						 hard_limit);
+		/* command line loader disabled or no initrd= passed? */
+		if (status == EFI_UNSUPPORTED || status == EFI_NOT_READY)
+			return EFI_SUCCESS;
+		if (status == EFI_SUCCESS)
+			efi_info("Loaded initrd from command line option\n");
+	}
+	if (status != EFI_SUCCESS)
+		goto failed;
+
+	status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, sizeof(initrd),
+			     (void **)&tbl);
+	if (status != EFI_SUCCESS)
+		goto free_initrd;
+
+	*tbl = initrd;
+	status = efi_bs_call(install_configuration_table, &tbl_guid, tbl);
+	if (status != EFI_SUCCESS)
+		goto free_tbl;
+
+	if (out)
+		*out = tbl;
+	return EFI_SUCCESS;
+
+free_tbl:
+	efi_bs_call(free_pool, tbl);
+free_initrd:
+	efi_free(initrd.size, initrd.base);
+failed:
+	efi_err("Failed to load initrd: 0x%lx\n", status);
+	return status;
+}
+
+/**
+ * efi_wait_for_key() - Wait for key stroke
+ * @usec:	number of microseconds to wait for key stroke
+ * @key:	key entered
+ *
+ * Wait for up to @usec microseconds for a key stroke.
+ *
+ * Return:	status code, EFI_SUCCESS if key received
+ */
+efi_status_t efi_wait_for_key(unsigned long usec, efi_input_key_t *key)
+{
+	efi_event_t events[2], timer;
+	unsigned long index;
+	efi_simple_text_input_protocol_t *con_in;
+	efi_status_t status;
+
+	con_in = efi_table_attr(efi_system_table, con_in);
+	if (!con_in)
+		return EFI_UNSUPPORTED;
+	efi_set_event_at(events, 0, efi_table_attr(con_in, wait_for_key));
+
+	status = efi_bs_call(create_event, EFI_EVT_TIMER, 0, NULL, NULL, &timer);
+	if (status != EFI_SUCCESS)
+		return status;
+
+	status = efi_bs_call(set_timer, timer, EfiTimerRelative,
+			     EFI_100NSEC_PER_USEC * usec);
+	if (status != EFI_SUCCESS)
+		return status;
+	efi_set_event_at(events, 1, timer);
+
+	status = efi_bs_call(wait_for_event, 2, events, &index);
+	if (status == EFI_SUCCESS) {
+		if (index == 0)
+			status = efi_call_proto(con_in, read_keystroke, key);
+		else
+			status = EFI_TIMEOUT;
+	}
+
+	efi_bs_call(close_event, timer);
+
+	return status;
+}
diff --git a/drivers/firmware/efi/libstub/efi-stub.c b/drivers/firmware/efi/libstub/efi-stub.c
new file mode 100644
index 000000000..cf474f0dd
--- /dev/null
+++ b/drivers/firmware/efi/libstub/efi-stub.c
@@ -0,0 +1,357 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * EFI stub implementation that is shared by arm and arm64 architectures.
+ * This should be #included by the EFI stub implementation files.
+ *
+ * Copyright (C) 2013,2014 Linaro Limited
+ *     Roy Franz <roy.franz@linaro.org
+ * Copyright (C) 2013 Red Hat, Inc.
+ *     Mark Salter <msalter@redhat.com>
+ */
+
+#include <linux/efi.h>
+#include <asm/efi.h>
+
+#include "efistub.h"
+
+/*
+ * This is the base address at which to start allocating virtual memory ranges
+ * for UEFI Runtime Services.
+ *
+ * For ARM/ARM64:
+ * This is in the low TTBR0 range so that we can use
+ * any allocation we choose, and eliminate the risk of a conflict after kexec.
+ * The value chosen is the largest non-zero power of 2 suitable for this purpose
+ * both on 32-bit and 64-bit ARM CPUs, to maximize the likelihood that it can
+ * be mapped efficiently.
+ * Since 32-bit ARM could potentially execute with a 1G/3G user/kernel split,
+ * map everything below 1 GB. (512 MB is a reasonable upper bound for the
+ * entire footprint of the UEFI runtime services memory regions)
+ *
+ * For RISC-V:
+ * There is no specific reason for which, this address (512MB) can't be used
+ * EFI runtime virtual address for RISC-V. It also helps to use EFI runtime
+ * services on both RV32/RV64. Keep the same runtime virtual address for RISC-V
+ * as well to minimize the code churn.
+ */
+#define EFI_RT_VIRTUAL_BASE	SZ_512M
+#define EFI_RT_VIRTUAL_SIZE	SZ_512M
+
+#ifdef CONFIG_ARM64
+# define EFI_RT_VIRTUAL_LIMIT	DEFAULT_MAP_WINDOW_64
+#elif defined(CONFIG_RISCV) || defined(CONFIG_LOONGARCH)
+# define EFI_RT_VIRTUAL_LIMIT	TASK_SIZE_MIN
+#else /* Only if TASK_SIZE is a constant */
+# define EFI_RT_VIRTUAL_LIMIT	TASK_SIZE
+#endif
+
+/*
+ * Some architectures map the EFI regions into the kernel's linear map using a
+ * fixed offset.
+ */
+#ifndef EFI_RT_VIRTUAL_OFFSET
+#define EFI_RT_VIRTUAL_OFFSET	0
+#endif
+
+static u64 virtmap_base = EFI_RT_VIRTUAL_BASE;
+static bool flat_va_mapping = (EFI_RT_VIRTUAL_OFFSET != 0);
+
+static struct screen_info *setup_graphics(void)
+{
+	efi_guid_t gop_proto = EFI_GRAPHICS_OUTPUT_PROTOCOL_GUID;
+	efi_status_t status;
+	unsigned long size;
+	void **gop_handle = NULL;
+	struct screen_info *si = NULL;
+
+	size = 0;
+	status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL,
+			     &gop_proto, NULL, &size, gop_handle);
+	if (status == EFI_BUFFER_TOO_SMALL) {
+		si = alloc_screen_info();
+		if (!si)
+			return NULL;
+		status = efi_setup_gop(si, &gop_proto, size);
+		if (status != EFI_SUCCESS) {
+			free_screen_info(si);
+			return NULL;
+		}
+	}
+	return si;
+}
+
+static void install_memreserve_table(void)
+{
+	struct linux_efi_memreserve *rsv;
+	efi_guid_t memreserve_table_guid = LINUX_EFI_MEMRESERVE_TABLE_GUID;
+	efi_status_t status;
+
+	status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, sizeof(*rsv),
+			     (void **)&rsv);
+	if (status != EFI_SUCCESS) {
+		efi_err("Failed to allocate memreserve entry!\n");
+		return;
+	}
+
+	rsv->next = 0;
+	rsv->size = 0;
+	atomic_set(&rsv->count, 0);
+
+	status = efi_bs_call(install_configuration_table,
+			     &memreserve_table_guid, rsv);
+	if (status != EFI_SUCCESS)
+		efi_err("Failed to install memreserve config table!\n");
+}
+
+static u32 get_supported_rt_services(void)
+{
+	const efi_rt_properties_table_t *rt_prop_table;
+	u32 supported = EFI_RT_SUPPORTED_ALL;
+
+	rt_prop_table = get_efi_config_table(EFI_RT_PROPERTIES_TABLE_GUID);
+	if (rt_prop_table)
+		supported &= rt_prop_table->runtime_services_supported;
+
+	return supported;
+}
+
+/*
+ * EFI entry point for the arm/arm64 EFI stubs.  This is the entrypoint
+ * that is described in the PE/COFF header.  Most of the code is the same
+ * for both archictectures, with the arch-specific code provided in the
+ * handle_kernel_image() function.
+ */
+efi_status_t __efiapi efi_pe_entry(efi_handle_t handle,
+				   efi_system_table_t *sys_table_arg)
+{
+	efi_loaded_image_t *image;
+	efi_status_t status;
+	unsigned long image_addr;
+	unsigned long image_size = 0;
+	/* addr/point and size pairs for memory management*/
+	char *cmdline_ptr = NULL;
+	int cmdline_size = 0;
+	efi_guid_t loaded_image_proto = LOADED_IMAGE_PROTOCOL_GUID;
+	unsigned long reserve_addr = 0;
+	unsigned long reserve_size = 0;
+	struct screen_info *si;
+	efi_properties_table_t *prop_tbl;
+
+	efi_system_table = sys_table_arg;
+
+	/* Check if we were booted by the EFI firmware */
+	if (efi_system_table->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE) {
+		status = EFI_INVALID_PARAMETER;
+		goto fail;
+	}
+
+	status = check_platform_features();
+	if (status != EFI_SUCCESS)
+		goto fail;
+
+	/*
+	 * Get a handle to the loaded image protocol.  This is used to get
+	 * information about the running image, such as size and the command
+	 * line.
+	 */
+	status = efi_bs_call(handle_protocol, handle, &loaded_image_proto,
+			     (void *)&image);
+	if (status != EFI_SUCCESS) {
+		efi_err("Failed to get loaded image protocol\n");
+		goto fail;
+	}
+
+	/*
+	 * Get the command line from EFI, using the LOADED_IMAGE
+	 * protocol. We are going to copy the command line into the
+	 * device tree, so this can be allocated anywhere.
+	 */
+	cmdline_ptr = efi_convert_cmdline(image, &cmdline_size);
+	if (!cmdline_ptr) {
+		efi_err("getting command line via LOADED_IMAGE_PROTOCOL\n");
+		status = EFI_OUT_OF_RESOURCES;
+		goto fail;
+	}
+
+	if (IS_ENABLED(CONFIG_CMDLINE_EXTEND) ||
+	    IS_ENABLED(CONFIG_CMDLINE_FORCE) ||
+	    cmdline_size == 0) {
+		status = efi_parse_options(CONFIG_CMDLINE);
+		if (status != EFI_SUCCESS) {
+			efi_err("Failed to parse options\n");
+			goto fail_free_cmdline;
+		}
+	}
+
+	if (!IS_ENABLED(CONFIG_CMDLINE_FORCE) && cmdline_size > 0) {
+		status = efi_parse_options(cmdline_ptr);
+		if (status != EFI_SUCCESS) {
+			efi_err("Failed to parse options\n");
+			goto fail_free_cmdline;
+		}
+	}
+
+	efi_info("Booting Linux Kernel...\n");
+
+	si = setup_graphics();
+
+	status = handle_kernel_image(&image_addr, &image_size,
+				     &reserve_addr,
+				     &reserve_size,
+				     image, handle);
+	if (status != EFI_SUCCESS) {
+		efi_err("Failed to relocate kernel\n");
+		goto fail_free_screeninfo;
+	}
+
+	efi_retrieve_tpm2_eventlog();
+
+	/* Ask the firmware to clear memory on unclean shutdown */
+	efi_enable_reset_attack_mitigation();
+
+	efi_load_initrd(image, ULONG_MAX, efi_get_max_initrd_addr(image_addr),
+			NULL);
+
+	efi_random_get_seed();
+
+	/*
+	 * If the NX PE data feature is enabled in the properties table, we
+	 * should take care not to create a virtual mapping that changes the
+	 * relative placement of runtime services code and data regions, as
+	 * they may belong to the same PE/COFF executable image in memory.
+	 * The easiest way to achieve that is to simply use a 1:1 mapping.
+	 */
+	prop_tbl = get_efi_config_table(EFI_PROPERTIES_TABLE_GUID);
+	flat_va_mapping |= prop_tbl &&
+			   (prop_tbl->memory_protection_attribute &
+			   EFI_PROPERTIES_RUNTIME_MEMORY_PROTECTION_NON_EXECUTABLE_PE_DATA);
+
+	/* force efi_novamap if SetVirtualAddressMap() is unsupported */
+	efi_novamap |= !(get_supported_rt_services() &
+			 EFI_RT_SUPPORTED_SET_VIRTUAL_ADDRESS_MAP);
+
+	/* hibernation expects the runtime regions to stay in the same place */
+	if (!IS_ENABLED(CONFIG_HIBERNATION) && !efi_nokaslr && !flat_va_mapping) {
+		/*
+		 * Randomize the base of the UEFI runtime services region.
+		 * Preserve the 2 MB alignment of the region by taking a
+		 * shift of 21 bit positions into account when scaling
+		 * the headroom value using a 32-bit random value.
+		 */
+		static const u64 headroom = EFI_RT_VIRTUAL_LIMIT -
+					    EFI_RT_VIRTUAL_BASE -
+					    EFI_RT_VIRTUAL_SIZE;
+		u32 rnd;
+
+		status = efi_get_random_bytes(sizeof(rnd), (u8 *)&rnd);
+		if (status == EFI_SUCCESS) {
+			virtmap_base = EFI_RT_VIRTUAL_BASE +
+				       (((headroom >> 21) * rnd) >> (32 - 21));
+		}
+	}
+
+	install_memreserve_table();
+
+	status = efi_boot_kernel(handle, image, image_addr, cmdline_ptr);
+
+	efi_free(image_size, image_addr);
+	efi_free(reserve_size, reserve_addr);
+fail_free_screeninfo:
+	free_screen_info(si);
+fail_free_cmdline:
+	efi_bs_call(free_pool, cmdline_ptr);
+fail:
+	return status;
+}
+
+/*
+ * efi_allocate_virtmap() - create a pool allocation for the virtmap
+ *
+ * Create an allocation that is of sufficient size to hold all the memory
+ * descriptors that will be passed to SetVirtualAddressMap() to inform the
+ * firmware about the virtual mapping that will be used under the OS to call
+ * into the firmware.
+ */
+efi_status_t efi_alloc_virtmap(efi_memory_desc_t **virtmap,
+			       unsigned long *desc_size, u32 *desc_ver)
+{
+	unsigned long size, mmap_key;
+	efi_status_t status;
+
+	/*
+	 * Use the size of the current memory map as an upper bound for the
+	 * size of the buffer we need to pass to SetVirtualAddressMap() to
+	 * cover all EFI_MEMORY_RUNTIME regions.
+	 */
+	size = 0;
+	status = efi_bs_call(get_memory_map, &size, NULL, &mmap_key, desc_size,
+			     desc_ver);
+	if (status != EFI_BUFFER_TOO_SMALL)
+		return EFI_LOAD_ERROR;
+
+	return efi_bs_call(allocate_pool, EFI_LOADER_DATA, size,
+			   (void **)virtmap);
+}
+
+/*
+ * efi_get_virtmap() - create a virtual mapping for the EFI memory map
+ *
+ * This function populates the virt_addr fields of all memory region descriptors
+ * in @memory_map whose EFI_MEMORY_RUNTIME attribute is set. Those descriptors
+ * are also copied to @runtime_map, and their total count is returned in @count.
+ */
+void efi_get_virtmap(efi_memory_desc_t *memory_map, unsigned long map_size,
+		     unsigned long desc_size, efi_memory_desc_t *runtime_map,
+		     int *count)
+{
+	u64 efi_virt_base = virtmap_base;
+	efi_memory_desc_t *in, *out = runtime_map;
+	int l;
+
+	*count = 0;
+
+	for (l = 0; l < map_size; l += desc_size) {
+		u64 paddr, size;
+
+		in = (void *)memory_map + l;
+		if (!(in->attribute & EFI_MEMORY_RUNTIME))
+			continue;
+
+		paddr = in->phys_addr;
+		size = in->num_pages * EFI_PAGE_SIZE;
+
+		in->virt_addr = in->phys_addr + EFI_RT_VIRTUAL_OFFSET;
+		if (efi_novamap) {
+			continue;
+		}
+
+		/*
+		 * Make the mapping compatible with 64k pages: this allows
+		 * a 4k page size kernel to kexec a 64k page size kernel and
+		 * vice versa.
+		 */
+		if (!flat_va_mapping) {
+
+			paddr = round_down(in->phys_addr, SZ_64K);
+			size += in->phys_addr - paddr;
+
+			/*
+			 * Avoid wasting memory on PTEs by choosing a virtual
+			 * base that is compatible with section mappings if this
+			 * region has the appropriate size and physical
+			 * alignment. (Sections are 2 MB on 4k granule kernels)
+			 */
+			if (IS_ALIGNED(in->phys_addr, SZ_2M) && size >= SZ_2M)
+				efi_virt_base = round_up(efi_virt_base, SZ_2M);
+			else
+				efi_virt_base = round_up(efi_virt_base, SZ_64K);
+
+			in->virt_addr += efi_virt_base - paddr;
+			efi_virt_base += size;
+		}
+
+		memcpy(out, in, desc_size);
+		out = (void *)out + desc_size;
+		++*count;
+	}
+}
diff --git a/drivers/firmware/efi/libstub/efistub.h b/drivers/firmware/efi/libstub/efistub.h
new file mode 100644
index 000000000..970e86e3a
--- /dev/null
+++ b/drivers/firmware/efi/libstub/efistub.h
@@ -0,0 +1,1043 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef _DRIVERS_FIRMWARE_EFI_EFISTUB_H
+#define _DRIVERS_FIRMWARE_EFI_EFISTUB_H
+
+#include <linux/compiler.h>
+#include <linux/efi.h>
+#include <linux/kernel.h>
+#include <linux/kern_levels.h>
+#include <linux/types.h>
+#include <asm/efi.h>
+
+/*
+ * __init annotations should not be used in the EFI stub, since the code is
+ * either included in the decompressor (x86, ARM) where they have no effect,
+ * or the whole stub is __init annotated at the section level (arm64), by
+ * renaming the sections, in which case the __init annotation will be
+ * redundant, and will result in section names like .init.init.text, and our
+ * linker script does not expect that.
+ */
+#undef __init
+
+/*
+ * Allow the platform to override the allocation granularity: this allows
+ * systems that have the capability to run with a larger page size to deal
+ * with the allocations for initrd and fdt more efficiently.
+ */
+#ifndef EFI_ALLOC_ALIGN
+#define EFI_ALLOC_ALIGN		EFI_PAGE_SIZE
+#endif
+
+extern bool efi_nochunk;
+extern bool efi_nokaslr;
+extern int efi_loglevel;
+extern bool efi_novamap;
+
+extern const efi_system_table_t *efi_system_table;
+
+typedef union efi_dxe_services_table efi_dxe_services_table_t;
+extern const efi_dxe_services_table_t *efi_dxe_table;
+
+efi_status_t __efiapi efi_pe_entry(efi_handle_t handle,
+				   efi_system_table_t *sys_table_arg);
+
+#ifndef ARCH_HAS_EFISTUB_WRAPPERS
+
+#define efi_is_native()		(true)
+#define efi_bs_call(func, ...)	efi_system_table->boottime->func(__VA_ARGS__)
+#define efi_rt_call(func, ...)	efi_system_table->runtime->func(__VA_ARGS__)
+#define efi_dxe_call(func, ...)	efi_dxe_table->func(__VA_ARGS__)
+#define efi_table_attr(inst, attr)	(inst->attr)
+#define efi_call_proto(inst, func, ...) inst->func(inst, ##__VA_ARGS__)
+
+#endif
+
+#define efi_info(fmt, ...) \
+	efi_printk(KERN_INFO fmt, ##__VA_ARGS__)
+#define efi_warn(fmt, ...) \
+	efi_printk(KERN_WARNING "WARNING: " fmt, ##__VA_ARGS__)
+#define efi_err(fmt, ...) \
+	efi_printk(KERN_ERR "ERROR: " fmt, ##__VA_ARGS__)
+#define efi_debug(fmt, ...) \
+	efi_printk(KERN_DEBUG "DEBUG: " fmt, ##__VA_ARGS__)
+
+#define efi_printk_once(fmt, ...) 		\
+({						\
+	static bool __print_once;		\
+	bool __ret_print_once = !__print_once;	\
+						\
+	if (!__print_once) {			\
+		__print_once = true;		\
+		efi_printk(fmt, ##__VA_ARGS__);	\
+	}					\
+	__ret_print_once;			\
+})
+
+#define efi_info_once(fmt, ...) \
+	efi_printk_once(KERN_INFO fmt, ##__VA_ARGS__)
+#define efi_warn_once(fmt, ...) \
+	efi_printk_once(KERN_WARNING "WARNING: " fmt, ##__VA_ARGS__)
+#define efi_err_once(fmt, ...) \
+	efi_printk_once(KERN_ERR "ERROR: " fmt, ##__VA_ARGS__)
+#define efi_debug_once(fmt, ...) \
+	efi_printk_once(KERN_DEBUG "DEBUG: " fmt, ##__VA_ARGS__)
+
+/* Helper macros for the usual case of using simple C variables: */
+#ifndef fdt_setprop_inplace_var
+#define fdt_setprop_inplace_var(fdt, node_offset, name, var) \
+	fdt_setprop_inplace((fdt), (node_offset), (name), &(var), sizeof(var))
+#endif
+
+#ifndef fdt_setprop_var
+#define fdt_setprop_var(fdt, node_offset, name, var) \
+	fdt_setprop((fdt), (node_offset), (name), &(var), sizeof(var))
+#endif
+
+#define get_efi_var(name, vendor, ...)				\
+	efi_rt_call(get_variable, (efi_char16_t *)(name),	\
+		    (efi_guid_t *)(vendor), __VA_ARGS__)
+
+#define set_efi_var(name, vendor, ...)				\
+	efi_rt_call(set_variable, (efi_char16_t *)(name),	\
+		    (efi_guid_t *)(vendor), __VA_ARGS__)
+
+#define efi_get_handle_at(array, idx)					\
+	(efi_is_native() ? (array)[idx] 				\
+		: (efi_handle_t)(unsigned long)((u32 *)(array))[idx])
+
+#define efi_get_handle_num(size)					\
+	((size) / (efi_is_native() ? sizeof(efi_handle_t) : sizeof(u32)))
+
+#define for_each_efi_handle(handle, array, size, i)			\
+	for (i = 0;							\
+	     i < efi_get_handle_num(size) &&				\
+		((handle = efi_get_handle_at((array), i)) || true);	\
+	     i++)
+
+static inline
+void efi_set_u64_split(u64 data, u32 *lo, u32 *hi)
+{
+	*lo = lower_32_bits(data);
+	*hi = upper_32_bits(data);
+}
+
+/*
+ * Allocation types for calls to boottime->allocate_pages.
+ */
+#define EFI_ALLOCATE_ANY_PAGES		0
+#define EFI_ALLOCATE_MAX_ADDRESS	1
+#define EFI_ALLOCATE_ADDRESS		2
+#define EFI_MAX_ALLOCATE_TYPE		3
+
+/*
+ * The type of search to perform when calling boottime->locate_handle
+ */
+#define EFI_LOCATE_ALL_HANDLES			0
+#define EFI_LOCATE_BY_REGISTER_NOTIFY		1
+#define EFI_LOCATE_BY_PROTOCOL			2
+
+/*
+ * boottime->stall takes the time period in microseconds
+ */
+#define EFI_USEC_PER_SEC		1000000
+
+/*
+ * boottime->set_timer takes the time in 100ns units
+ */
+#define EFI_100NSEC_PER_USEC	((u64)10)
+
+/*
+ * An efi_boot_memmap is used by efi_get_memory_map() to return the
+ * EFI memory map in a dynamically allocated buffer.
+ *
+ * The buffer allocated for the EFI memory map includes extra room for
+ * a minimum of EFI_MMAP_NR_SLACK_SLOTS additional EFI memory descriptors.
+ * This facilitates the reuse of the EFI memory map buffer when a second
+ * call to ExitBootServices() is needed because of intervening changes to
+ * the EFI memory map. Other related structures, e.g. x86 e820ext, need
+ * to factor in this headroom requirement as well.
+ */
+#define EFI_MMAP_NR_SLACK_SLOTS	8
+
+typedef struct efi_generic_dev_path efi_device_path_protocol_t;
+
+union efi_device_path_to_text_protocol {
+	struct {
+		efi_char16_t *(__efiapi *convert_device_node_to_text)(
+					const efi_device_path_protocol_t *,
+					bool, bool);
+		efi_char16_t *(__efiapi *convert_device_path_to_text)(
+					const efi_device_path_protocol_t *,
+					bool, bool);
+	};
+	struct {
+		u32 convert_device_node_to_text;
+		u32 convert_device_path_to_text;
+	} mixed_mode;
+};
+
+typedef union efi_device_path_to_text_protocol efi_device_path_to_text_protocol_t;
+
+typedef void *efi_event_t;
+/* Note that notifications won't work in mixed mode */
+typedef void (__efiapi *efi_event_notify_t)(efi_event_t, void *);
+
+#define EFI_EVT_TIMER		0x80000000U
+#define EFI_EVT_RUNTIME		0x40000000U
+#define EFI_EVT_NOTIFY_WAIT	0x00000100U
+#define EFI_EVT_NOTIFY_SIGNAL	0x00000200U
+
+/**
+ * efi_set_event_at() - add event to events array
+ *
+ * @events:	array of UEFI events
+ * @ids:	index where to put the event in the array
+ * @event:	event to add to the aray
+ *
+ * boottime->wait_for_event() takes an array of events as input.
+ * Provide a helper to set it up correctly for mixed mode.
+ */
+static inline
+void efi_set_event_at(efi_event_t *events, size_t idx, efi_event_t event)
+{
+	if (efi_is_native())
+		events[idx] = event;
+	else
+		((u32 *)events)[idx] = (u32)(unsigned long)event;
+}
+
+#define EFI_TPL_APPLICATION	4
+#define EFI_TPL_CALLBACK	8
+#define EFI_TPL_NOTIFY		16
+#define EFI_TPL_HIGH_LEVEL	31
+
+typedef enum {
+	EfiTimerCancel,
+	EfiTimerPeriodic,
+	EfiTimerRelative
+} EFI_TIMER_DELAY;
+
+/*
+ * EFI Boot Services table
+ */
+union efi_boot_services {
+	struct {
+		efi_table_hdr_t hdr;
+		void *raise_tpl;
+		void *restore_tpl;
+		efi_status_t (__efiapi *allocate_pages)(int, int, unsigned long,
+							efi_physical_addr_t *);
+		efi_status_t (__efiapi *free_pages)(efi_physical_addr_t,
+						    unsigned long);
+		efi_status_t (__efiapi *get_memory_map)(unsigned long *, void *,
+							unsigned long *,
+							unsigned long *, u32 *);
+		efi_status_t (__efiapi *allocate_pool)(int, unsigned long,
+						       void **);
+		efi_status_t (__efiapi *free_pool)(void *);
+		efi_status_t (__efiapi *create_event)(u32, unsigned long,
+						      efi_event_notify_t, void *,
+						      efi_event_t *);
+		efi_status_t (__efiapi *set_timer)(efi_event_t,
+						  EFI_TIMER_DELAY, u64);
+		efi_status_t (__efiapi *wait_for_event)(unsigned long,
+							efi_event_t *,
+							unsigned long *);
+		void *signal_event;
+		efi_status_t (__efiapi *close_event)(efi_event_t);
+		void *check_event;
+		void *install_protocol_interface;
+		void *reinstall_protocol_interface;
+		void *uninstall_protocol_interface;
+		efi_status_t (__efiapi *handle_protocol)(efi_handle_t,
+							 efi_guid_t *, void **);
+		void *__reserved;
+		void *register_protocol_notify;
+		efi_status_t (__efiapi *locate_handle)(int, efi_guid_t *,
+						       void *, unsigned long *,
+						       efi_handle_t *);
+		efi_status_t (__efiapi *locate_device_path)(efi_guid_t *,
+							    efi_device_path_protocol_t **,
+							    efi_handle_t *);
+		efi_status_t (__efiapi *install_configuration_table)(efi_guid_t *,
+								     void *);
+		efi_status_t (__efiapi *load_image)(bool, efi_handle_t,
+						    efi_device_path_protocol_t *,
+						    void *, unsigned long,
+						    efi_handle_t *);
+		efi_status_t (__efiapi *start_image)(efi_handle_t, unsigned long *,
+						     efi_char16_t **);
+		efi_status_t __noreturn (__efiapi *exit)(efi_handle_t,
+							 efi_status_t,
+							 unsigned long,
+							 efi_char16_t *);
+		efi_status_t (__efiapi *unload_image)(efi_handle_t);
+		efi_status_t (__efiapi *exit_boot_services)(efi_handle_t,
+							    unsigned long);
+		void *get_next_monotonic_count;
+		efi_status_t (__efiapi *stall)(unsigned long);
+		void *set_watchdog_timer;
+		void *connect_controller;
+		efi_status_t (__efiapi *disconnect_controller)(efi_handle_t,
+							       efi_handle_t,
+							       efi_handle_t);
+		void *open_protocol;
+		void *close_protocol;
+		void *open_protocol_information;
+		void *protocols_per_handle;
+		void *locate_handle_buffer;
+		efi_status_t (__efiapi *locate_protocol)(efi_guid_t *, void *,
+							 void **);
+		efi_status_t (__efiapi *install_multiple_protocol_interfaces)(efi_handle_t *, ...);
+		efi_status_t (__efiapi *uninstall_multiple_protocol_interfaces)(efi_handle_t, ...);
+		void *calculate_crc32;
+		void (__efiapi *copy_mem)(void *, const void *, unsigned long);
+		void (__efiapi *set_mem)(void *, unsigned long, unsigned char);
+		void *create_event_ex;
+	};
+	struct {
+		efi_table_hdr_t hdr;
+		u32 raise_tpl;
+		u32 restore_tpl;
+		u32 allocate_pages;
+		u32 free_pages;
+		u32 get_memory_map;
+		u32 allocate_pool;
+		u32 free_pool;
+		u32 create_event;
+		u32 set_timer;
+		u32 wait_for_event;
+		u32 signal_event;
+		u32 close_event;
+		u32 check_event;
+		u32 install_protocol_interface;
+		u32 reinstall_protocol_interface;
+		u32 uninstall_protocol_interface;
+		u32 handle_protocol;
+		u32 __reserved;
+		u32 register_protocol_notify;
+		u32 locate_handle;
+		u32 locate_device_path;
+		u32 install_configuration_table;
+		u32 load_image;
+		u32 start_image;
+		u32 exit;
+		u32 unload_image;
+		u32 exit_boot_services;
+		u32 get_next_monotonic_count;
+		u32 stall;
+		u32 set_watchdog_timer;
+		u32 connect_controller;
+		u32 disconnect_controller;
+		u32 open_protocol;
+		u32 close_protocol;
+		u32 open_protocol_information;
+		u32 protocols_per_handle;
+		u32 locate_handle_buffer;
+		u32 locate_protocol;
+		u32 install_multiple_protocol_interfaces;
+		u32 uninstall_multiple_protocol_interfaces;
+		u32 calculate_crc32;
+		u32 copy_mem;
+		u32 set_mem;
+		u32 create_event_ex;
+	} mixed_mode;
+};
+
+typedef enum {
+	EfiGcdMemoryTypeNonExistent,
+	EfiGcdMemoryTypeReserved,
+	EfiGcdMemoryTypeSystemMemory,
+	EfiGcdMemoryTypeMemoryMappedIo,
+	EfiGcdMemoryTypePersistent,
+	EfiGcdMemoryTypeMoreReliable,
+	EfiGcdMemoryTypeMaximum
+} efi_gcd_memory_type_t;
+
+typedef struct {
+	efi_physical_addr_t base_address;
+	u64 length;
+	u64 capabilities;
+	u64 attributes;
+	efi_gcd_memory_type_t gcd_memory_type;
+	void *image_handle;
+	void *device_handle;
+} efi_gcd_memory_space_desc_t;
+
+/*
+ * EFI DXE Services table
+ */
+union efi_dxe_services_table {
+	struct {
+		efi_table_hdr_t hdr;
+		void *add_memory_space;
+		void *allocate_memory_space;
+		void *free_memory_space;
+		void *remove_memory_space;
+		efi_status_t (__efiapi *get_memory_space_descriptor)(efi_physical_addr_t,
+								     efi_gcd_memory_space_desc_t *);
+		efi_status_t (__efiapi *set_memory_space_attributes)(efi_physical_addr_t,
+								     u64, u64);
+		void *get_memory_space_map;
+		void *add_io_space;
+		void *allocate_io_space;
+		void *free_io_space;
+		void *remove_io_space;
+		void *get_io_space_descriptor;
+		void *get_io_space_map;
+		void *dispatch;
+		void *schedule;
+		void *trust;
+		void *process_firmware_volume;
+		void *set_memory_space_capabilities;
+	};
+	struct {
+		efi_table_hdr_t hdr;
+		u32 add_memory_space;
+		u32 allocate_memory_space;
+		u32 free_memory_space;
+		u32 remove_memory_space;
+		u32 get_memory_space_descriptor;
+		u32 set_memory_space_attributes;
+		u32 get_memory_space_map;
+		u32 add_io_space;
+		u32 allocate_io_space;
+		u32 free_io_space;
+		u32 remove_io_space;
+		u32 get_io_space_descriptor;
+		u32 get_io_space_map;
+		u32 dispatch;
+		u32 schedule;
+		u32 trust;
+		u32 process_firmware_volume;
+		u32 set_memory_space_capabilities;
+	} mixed_mode;
+};
+
+typedef union efi_uga_draw_protocol efi_uga_draw_protocol_t;
+
+union efi_uga_draw_protocol {
+	struct {
+		efi_status_t (__efiapi *get_mode)(efi_uga_draw_protocol_t *,
+						  u32*, u32*, u32*, u32*);
+		void *set_mode;
+		void *blt;
+	};
+	struct {
+		u32 get_mode;
+		u32 set_mode;
+		u32 blt;
+	} mixed_mode;
+};
+
+typedef struct {
+	u16 scan_code;
+	efi_char16_t unicode_char;
+} efi_input_key_t;
+
+union efi_simple_text_input_protocol {
+	struct {
+		void *reset;
+		efi_status_t (__efiapi *read_keystroke)(efi_simple_text_input_protocol_t *,
+							efi_input_key_t *);
+		efi_event_t wait_for_key;
+	};
+	struct {
+		u32 reset;
+		u32 read_keystroke;
+		u32 wait_for_key;
+	} mixed_mode;
+};
+
+efi_status_t efi_wait_for_key(unsigned long usec, efi_input_key_t *key);
+
+union efi_simple_text_output_protocol {
+	struct {
+		void *reset;
+		efi_status_t (__efiapi *output_string)(efi_simple_text_output_protocol_t *,
+						       efi_char16_t *);
+		void *test_string;
+	};
+	struct {
+		u32 reset;
+		u32 output_string;
+		u32 test_string;
+	} mixed_mode;
+};
+
+#define PIXEL_RGB_RESERVED_8BIT_PER_COLOR		0
+#define PIXEL_BGR_RESERVED_8BIT_PER_COLOR		1
+#define PIXEL_BIT_MASK					2
+#define PIXEL_BLT_ONLY					3
+#define PIXEL_FORMAT_MAX				4
+
+typedef struct {
+	u32 red_mask;
+	u32 green_mask;
+	u32 blue_mask;
+	u32 reserved_mask;
+} efi_pixel_bitmask_t;
+
+typedef struct {
+	u32 version;
+	u32 horizontal_resolution;
+	u32 vertical_resolution;
+	int pixel_format;
+	efi_pixel_bitmask_t pixel_information;
+	u32 pixels_per_scan_line;
+} efi_graphics_output_mode_info_t;
+
+typedef union efi_graphics_output_protocol_mode efi_graphics_output_protocol_mode_t;
+
+union efi_graphics_output_protocol_mode {
+	struct {
+		u32 max_mode;
+		u32 mode;
+		efi_graphics_output_mode_info_t *info;
+		unsigned long size_of_info;
+		efi_physical_addr_t frame_buffer_base;
+		unsigned long frame_buffer_size;
+	};
+	struct {
+		u32 max_mode;
+		u32 mode;
+		u32 info;
+		u32 size_of_info;
+		u64 frame_buffer_base;
+		u32 frame_buffer_size;
+	} mixed_mode;
+};
+
+typedef union efi_graphics_output_protocol efi_graphics_output_protocol_t;
+
+union efi_graphics_output_protocol {
+	struct {
+		efi_status_t (__efiapi *query_mode)(efi_graphics_output_protocol_t *,
+						    u32, unsigned long *,
+						    efi_graphics_output_mode_info_t **);
+		efi_status_t (__efiapi *set_mode)  (efi_graphics_output_protocol_t *, u32);
+		void *blt;
+		efi_graphics_output_protocol_mode_t *mode;
+	};
+	struct {
+		u32 query_mode;
+		u32 set_mode;
+		u32 blt;
+		u32 mode;
+	} mixed_mode;
+};
+
+typedef union {
+	struct {
+		u32			revision;
+		efi_handle_t		parent_handle;
+		efi_system_table_t	*system_table;
+		efi_handle_t		device_handle;
+		void			*file_path;
+		void			*reserved;
+		u32			load_options_size;
+		void			*load_options;
+		void			*image_base;
+		__aligned_u64		image_size;
+		unsigned int		image_code_type;
+		unsigned int		image_data_type;
+		efi_status_t		(__efiapi *unload)(efi_handle_t image_handle);
+	};
+	struct {
+		u32		revision;
+		u32		parent_handle;
+		u32		system_table;
+		u32		device_handle;
+		u32		file_path;
+		u32		reserved;
+		u32		load_options_size;
+		u32		load_options;
+		u32		image_base;
+		__aligned_u64	image_size;
+		u32		image_code_type;
+		u32		image_data_type;
+		u32		unload;
+	} mixed_mode;
+} efi_loaded_image_t;
+
+typedef struct {
+	u64			size;
+	u64			file_size;
+	u64			phys_size;
+	efi_time_t		create_time;
+	efi_time_t		last_access_time;
+	efi_time_t		modification_time;
+	__aligned_u64		attribute;
+	efi_char16_t		filename[];
+} efi_file_info_t;
+
+typedef struct efi_file_protocol efi_file_protocol_t;
+
+struct efi_file_protocol {
+	u64		revision;
+	efi_status_t	(__efiapi *open)	(efi_file_protocol_t *,
+						 efi_file_protocol_t **,
+						 efi_char16_t *, u64, u64);
+	efi_status_t	(__efiapi *close)	(efi_file_protocol_t *);
+	efi_status_t	(__efiapi *delete)	(efi_file_protocol_t *);
+	efi_status_t	(__efiapi *read)	(efi_file_protocol_t *,
+						 unsigned long *, void *);
+	efi_status_t	(__efiapi *write)	(efi_file_protocol_t *,
+						 unsigned long, void *);
+	efi_status_t	(__efiapi *get_position)(efi_file_protocol_t *, u64 *);
+	efi_status_t	(__efiapi *set_position)(efi_file_protocol_t *, u64);
+	efi_status_t	(__efiapi *get_info)	(efi_file_protocol_t *,
+						 efi_guid_t *, unsigned long *,
+						 void *);
+	efi_status_t	(__efiapi *set_info)	(efi_file_protocol_t *,
+						 efi_guid_t *, unsigned long,
+						 void *);
+	efi_status_t	(__efiapi *flush)	(efi_file_protocol_t *);
+};
+
+typedef struct efi_simple_file_system_protocol efi_simple_file_system_protocol_t;
+
+struct efi_simple_file_system_protocol {
+	u64	revision;
+	int	(__efiapi *open_volume)(efi_simple_file_system_protocol_t *,
+					efi_file_protocol_t **);
+};
+
+#define EFI_FILE_MODE_READ	0x0000000000000001
+#define EFI_FILE_MODE_WRITE	0x0000000000000002
+#define EFI_FILE_MODE_CREATE	0x8000000000000000
+
+typedef enum {
+	EfiPciIoWidthUint8,
+	EfiPciIoWidthUint16,
+	EfiPciIoWidthUint32,
+	EfiPciIoWidthUint64,
+	EfiPciIoWidthFifoUint8,
+	EfiPciIoWidthFifoUint16,
+	EfiPciIoWidthFifoUint32,
+	EfiPciIoWidthFifoUint64,
+	EfiPciIoWidthFillUint8,
+	EfiPciIoWidthFillUint16,
+	EfiPciIoWidthFillUint32,
+	EfiPciIoWidthFillUint64,
+	EfiPciIoWidthMaximum
+} EFI_PCI_IO_PROTOCOL_WIDTH;
+
+typedef enum {
+	EfiPciIoAttributeOperationGet,
+	EfiPciIoAttributeOperationSet,
+	EfiPciIoAttributeOperationEnable,
+	EfiPciIoAttributeOperationDisable,
+	EfiPciIoAttributeOperationSupported,
+    EfiPciIoAttributeOperationMaximum
+} EFI_PCI_IO_PROTOCOL_ATTRIBUTE_OPERATION;
+
+typedef struct {
+	u32 read;
+	u32 write;
+} efi_pci_io_protocol_access_32_t;
+
+typedef union efi_pci_io_protocol efi_pci_io_protocol_t;
+
+typedef
+efi_status_t (__efiapi *efi_pci_io_protocol_cfg_t)(efi_pci_io_protocol_t *,
+						   EFI_PCI_IO_PROTOCOL_WIDTH,
+						   u32 offset,
+						   unsigned long count,
+						   void *buffer);
+
+typedef struct {
+	void *read;
+	void *write;
+} efi_pci_io_protocol_access_t;
+
+typedef struct {
+	efi_pci_io_protocol_cfg_t read;
+	efi_pci_io_protocol_cfg_t write;
+} efi_pci_io_protocol_config_access_t;
+
+union efi_pci_io_protocol {
+	struct {
+		void *poll_mem;
+		void *poll_io;
+		efi_pci_io_protocol_access_t mem;
+		efi_pci_io_protocol_access_t io;
+		efi_pci_io_protocol_config_access_t pci;
+		void *copy_mem;
+		void *map;
+		void *unmap;
+		void *allocate_buffer;
+		void *free_buffer;
+		void *flush;
+		efi_status_t (__efiapi *get_location)(efi_pci_io_protocol_t *,
+						      unsigned long *segment_nr,
+						      unsigned long *bus_nr,
+						      unsigned long *device_nr,
+						      unsigned long *func_nr);
+		void *attributes;
+		void *get_bar_attributes;
+		void *set_bar_attributes;
+		uint64_t romsize;
+		void *romimage;
+	};
+	struct {
+		u32 poll_mem;
+		u32 poll_io;
+		efi_pci_io_protocol_access_32_t mem;
+		efi_pci_io_protocol_access_32_t io;
+		efi_pci_io_protocol_access_32_t pci;
+		u32 copy_mem;
+		u32 map;
+		u32 unmap;
+		u32 allocate_buffer;
+		u32 free_buffer;
+		u32 flush;
+		u32 get_location;
+		u32 attributes;
+		u32 get_bar_attributes;
+		u32 set_bar_attributes;
+		u64 romsize;
+		u32 romimage;
+	} mixed_mode;
+};
+
+#define EFI_PCI_IO_ATTRIBUTE_ISA_MOTHERBOARD_IO 0x0001
+#define EFI_PCI_IO_ATTRIBUTE_ISA_IO 0x0002
+#define EFI_PCI_IO_ATTRIBUTE_VGA_PALETTE_IO 0x0004
+#define EFI_PCI_IO_ATTRIBUTE_VGA_MEMORY 0x0008
+#define EFI_PCI_IO_ATTRIBUTE_VGA_IO 0x0010
+#define EFI_PCI_IO_ATTRIBUTE_IDE_PRIMARY_IO 0x0020
+#define EFI_PCI_IO_ATTRIBUTE_IDE_SECONDARY_IO 0x0040
+#define EFI_PCI_IO_ATTRIBUTE_MEMORY_WRITE_COMBINE 0x0080
+#define EFI_PCI_IO_ATTRIBUTE_IO 0x0100
+#define EFI_PCI_IO_ATTRIBUTE_MEMORY 0x0200
+#define EFI_PCI_IO_ATTRIBUTE_BUS_MASTER 0x0400
+#define EFI_PCI_IO_ATTRIBUTE_MEMORY_CACHED 0x0800
+#define EFI_PCI_IO_ATTRIBUTE_MEMORY_DISABLE 0x1000
+#define EFI_PCI_IO_ATTRIBUTE_EMBEDDED_DEVICE 0x2000
+#define EFI_PCI_IO_ATTRIBUTE_EMBEDDED_ROM 0x4000
+#define EFI_PCI_IO_ATTRIBUTE_DUAL_ADDRESS_CYCLE 0x8000
+#define EFI_PCI_IO_ATTRIBUTE_ISA_IO_16 0x10000
+#define EFI_PCI_IO_ATTRIBUTE_VGA_PALETTE_IO_16 0x20000
+#define EFI_PCI_IO_ATTRIBUTE_VGA_IO_16 0x40000
+
+struct efi_dev_path;
+
+typedef union apple_properties_protocol apple_properties_protocol_t;
+
+union apple_properties_protocol {
+	struct {
+		unsigned long version;
+		efi_status_t (__efiapi *get)(apple_properties_protocol_t *,
+					     struct efi_dev_path *,
+					     efi_char16_t *, void *, u32 *);
+		efi_status_t (__efiapi *set)(apple_properties_protocol_t *,
+					     struct efi_dev_path *,
+					     efi_char16_t *, void *, u32);
+		efi_status_t (__efiapi *del)(apple_properties_protocol_t *,
+					     struct efi_dev_path *,
+					     efi_char16_t *);
+		efi_status_t (__efiapi *get_all)(apple_properties_protocol_t *,
+						 void *buffer, u32 *);
+	};
+	struct {
+		u32 version;
+		u32 get;
+		u32 set;
+		u32 del;
+		u32 get_all;
+	} mixed_mode;
+};
+
+typedef u32 efi_tcg2_event_log_format;
+
+#define INITRD_EVENT_TAG_ID 0x8F3B22ECU
+#define LOAD_OPTIONS_EVENT_TAG_ID 0x8F3B22EDU
+#define EV_EVENT_TAG 0x00000006U
+#define EFI_TCG2_EVENT_HEADER_VERSION	0x1
+
+struct efi_tcg2_event {
+	u32		event_size;
+	struct {
+		u32	header_size;
+		u16	header_version;
+		u32	pcr_index;
+		u32	event_type;
+	} __packed event_header;
+	/* u8[] event follows here */
+} __packed;
+
+struct efi_tcg2_tagged_event {
+	u32 tagged_event_id;
+	u32 tagged_event_data_size;
+	/* u8  tagged event data follows here */
+} __packed;
+
+typedef struct efi_tcg2_event efi_tcg2_event_t;
+typedef struct efi_tcg2_tagged_event efi_tcg2_tagged_event_t;
+typedef union efi_tcg2_protocol efi_tcg2_protocol_t;
+
+union efi_tcg2_protocol {
+	struct {
+		void *get_capability;
+		efi_status_t (__efiapi *get_event_log)(efi_tcg2_protocol_t *,
+						       efi_tcg2_event_log_format,
+						       efi_physical_addr_t *,
+						       efi_physical_addr_t *,
+						       efi_bool_t *);
+		efi_status_t (__efiapi *hash_log_extend_event)(efi_tcg2_protocol_t *,
+							       u64,
+							       efi_physical_addr_t,
+							       u64,
+							       const efi_tcg2_event_t *);
+		void *submit_command;
+		void *get_active_pcr_banks;
+		void *set_active_pcr_banks;
+		void *get_result_of_set_active_pcr_banks;
+	};
+	struct {
+		u32 get_capability;
+		u32 get_event_log;
+		u32 hash_log_extend_event;
+		u32 submit_command;
+		u32 get_active_pcr_banks;
+		u32 set_active_pcr_banks;
+		u32 get_result_of_set_active_pcr_banks;
+	} mixed_mode;
+};
+
+struct riscv_efi_boot_protocol {
+	u64 revision;
+
+	efi_status_t (__efiapi *get_boot_hartid)(struct riscv_efi_boot_protocol *,
+						 unsigned long *boot_hartid);
+};
+
+typedef union efi_load_file_protocol efi_load_file_protocol_t;
+typedef union efi_load_file_protocol efi_load_file2_protocol_t;
+
+union efi_load_file_protocol {
+	struct {
+		efi_status_t (__efiapi *load_file)(efi_load_file_protocol_t *,
+						   efi_device_path_protocol_t *,
+						   bool, unsigned long *, void *);
+	};
+	struct {
+		u32 load_file;
+	} mixed_mode;
+};
+
+typedef struct {
+	u32 attributes;
+	u16 file_path_list_length;
+	u8 variable_data[];
+	// efi_char16_t description[];
+	// efi_device_path_protocol_t file_path_list[];
+	// u8 optional_data[];
+} __packed efi_load_option_t;
+
+#define EFI_LOAD_OPTION_ACTIVE		0x0001U
+#define EFI_LOAD_OPTION_FORCE_RECONNECT	0x0002U
+#define EFI_LOAD_OPTION_HIDDEN		0x0008U
+#define EFI_LOAD_OPTION_CATEGORY	0x1f00U
+#define   EFI_LOAD_OPTION_CATEGORY_BOOT	0x0000U
+#define   EFI_LOAD_OPTION_CATEGORY_APP	0x0100U
+
+#define EFI_LOAD_OPTION_BOOT_MASK \
+	(EFI_LOAD_OPTION_ACTIVE|EFI_LOAD_OPTION_HIDDEN|EFI_LOAD_OPTION_CATEGORY)
+#define EFI_LOAD_OPTION_MASK (EFI_LOAD_OPTION_FORCE_RECONNECT|EFI_LOAD_OPTION_BOOT_MASK)
+
+typedef struct {
+	u32 attributes;
+	u16 file_path_list_length;
+	const efi_char16_t *description;
+	const efi_device_path_protocol_t *file_path_list;
+	u32 optional_data_size;
+	const void *optional_data;
+} efi_load_option_unpacked_t;
+
+void efi_pci_disable_bridge_busmaster(void);
+
+typedef efi_status_t (*efi_exit_boot_map_processing)(
+	struct efi_boot_memmap *map,
+	void *priv);
+
+efi_status_t efi_exit_boot_services(void *handle, void *priv,
+				    efi_exit_boot_map_processing priv_func);
+
+efi_status_t efi_boot_kernel(void *handle, efi_loaded_image_t *image,
+			     unsigned long kernel_addr, char *cmdline_ptr);
+
+void *get_fdt(unsigned long *fdt_size);
+
+efi_status_t efi_alloc_virtmap(efi_memory_desc_t **virtmap,
+			       unsigned long *desc_size, u32 *desc_ver);
+void efi_get_virtmap(efi_memory_desc_t *memory_map, unsigned long map_size,
+		     unsigned long desc_size, efi_memory_desc_t *runtime_map,
+		     int *count);
+
+efi_status_t efi_get_random_bytes(unsigned long size, u8 *out);
+
+efi_status_t efi_random_alloc(unsigned long size, unsigned long align,
+			      unsigned long *addr, unsigned long random_seed);
+
+efi_status_t efi_random_get_seed(void);
+
+efi_status_t check_platform_features(void);
+
+void *get_efi_config_table(efi_guid_t guid);
+
+/* NOTE: These functions do not print a trailing newline after the string */
+void efi_char16_puts(efi_char16_t *);
+void efi_puts(const char *str);
+
+__printf(1, 2) int efi_printk(char const *fmt, ...);
+
+void efi_free(unsigned long size, unsigned long addr);
+
+void efi_apply_loadoptions_quirk(const void **load_options, u32 *load_options_size);
+
+char *efi_convert_cmdline(efi_loaded_image_t *image, int *cmd_line_len);
+
+efi_status_t efi_get_memory_map(struct efi_boot_memmap **map,
+				bool install_cfg_tbl);
+
+efi_status_t efi_allocate_pages(unsigned long size, unsigned long *addr,
+				unsigned long max);
+
+efi_status_t efi_allocate_pages_aligned(unsigned long size, unsigned long *addr,
+					unsigned long max, unsigned long align);
+
+efi_status_t efi_low_alloc_above(unsigned long size, unsigned long align,
+				 unsigned long *addr, unsigned long min);
+
+efi_status_t efi_relocate_kernel(unsigned long *image_addr,
+				 unsigned long image_size,
+				 unsigned long alloc_size,
+				 unsigned long preferred_addr,
+				 unsigned long alignment,
+				 unsigned long min_addr);
+
+efi_status_t efi_parse_options(char const *cmdline);
+
+void efi_parse_option_graphics(char *option);
+
+efi_status_t efi_setup_gop(struct screen_info *si, efi_guid_t *proto,
+			   unsigned long size);
+
+efi_status_t handle_cmdline_files(efi_loaded_image_t *image,
+				  const efi_char16_t *optstr,
+				  int optstr_size,
+				  unsigned long soft_limit,
+				  unsigned long hard_limit,
+				  unsigned long *load_addr,
+				  unsigned long *load_size);
+
+
+static inline efi_status_t efi_load_dtb(efi_loaded_image_t *image,
+					unsigned long *load_addr,
+					unsigned long *load_size)
+{
+	return handle_cmdline_files(image, L"dtb=", sizeof(L"dtb=") - 2,
+				    ULONG_MAX, ULONG_MAX, load_addr, load_size);
+}
+
+efi_status_t efi_load_initrd(efi_loaded_image_t *image,
+			     unsigned long soft_limit,
+			     unsigned long hard_limit,
+			     const struct linux_efi_initrd **out);
+/*
+ * This function handles the architcture specific differences between arm and
+ * arm64 regarding where the kernel image must be loaded and any memory that
+ * must be reserved. On failure it is required to free all
+ * all allocations it has made.
+ */
+efi_status_t handle_kernel_image(unsigned long *image_addr,
+				 unsigned long *image_size,
+				 unsigned long *reserve_addr,
+				 unsigned long *reserve_size,
+				 efi_loaded_image_t *image,
+				 efi_handle_t image_handle);
+
+asmlinkage void __noreturn efi_enter_kernel(unsigned long entrypoint,
+					    unsigned long fdt_addr,
+					    unsigned long fdt_size);
+
+void efi_handle_post_ebs_state(void);
+
+enum efi_secureboot_mode efi_get_secureboot(void);
+
+#ifdef CONFIG_RESET_ATTACK_MITIGATION
+void efi_enable_reset_attack_mitigation(void);
+#else
+static inline void
+efi_enable_reset_attack_mitigation(void) { }
+#endif
+
+void efi_retrieve_tpm2_eventlog(void);
+
+struct efi_smbios_record {
+	u8	type;
+	u8	length;
+	u16	handle;
+};
+
+const struct efi_smbios_record *efi_get_smbios_record(u8 type);
+
+struct efi_smbios_type1_record {
+	struct efi_smbios_record	header;
+
+	u8				manufacturer;
+	u8				product_name;
+	u8				version;
+	u8				serial_number;
+	efi_guid_t			uuid;
+	u8				wakeup_type;
+	u8				sku_number;
+	u8				family;
+};
+
+struct efi_smbios_type4_record {
+	struct efi_smbios_record	header;
+
+	u8				socket;
+	u8				processor_type;
+	u8				processor_family;
+	u8				processor_manufacturer;
+	u8				processor_id[8];
+	u8				processor_version;
+	u8				voltage;
+	u16				external_clock;
+	u16				max_speed;
+	u16				current_speed;
+	u8				status;
+	u8				processor_upgrade;
+	u16				l1_cache_handle;
+	u16				l2_cache_handle;
+	u16				l3_cache_handle;
+	u8				serial_number;
+	u8				asset_tag;
+	u8				part_number;
+	u8				core_count;
+	u8				enabled_core_count;
+	u8				thread_count;
+	u16				processor_characteristics;
+	u16				processor_family2;
+	u16				core_count2;
+	u16				enabled_core_count2;
+	u16				thread_count2;
+	u16				thread_enabled;
+};
+
+#define efi_get_smbios_string(__record, __type, __name) ({		\
+	int size = sizeof(struct efi_smbios_type ## __type ## _record);	\
+	int off = offsetof(struct efi_smbios_type ## __type ## _record,	\
+			   __name);					\
+	__efi_get_smbios_string((__record), __type, off, size);		\
+})
+
+const u8 *__efi_get_smbios_string(const struct efi_smbios_record *record,
+				  u8 type, int offset, int recsize);
+
+#endif
diff --git a/drivers/firmware/efi/libstub/fdt.c b/drivers/firmware/efi/libstub/fdt.c
new file mode 100644
index 000000000..70e9789ff
--- /dev/null
+++ b/drivers/firmware/efi/libstub/fdt.c
@@ -0,0 +1,379 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * FDT related Helper functions used by the EFI stub on multiple
+ * architectures. This should be #included by the EFI stub
+ * implementation files.
+ *
+ * Copyright 2013 Linaro Limited; author Roy Franz
+ */
+
+#include <linux/efi.h>
+#include <linux/libfdt.h>
+#include <asm/efi.h>
+
+#include "efistub.h"
+
+#define EFI_DT_ADDR_CELLS_DEFAULT 2
+#define EFI_DT_SIZE_CELLS_DEFAULT 2
+
+static void fdt_update_cell_size(void *fdt)
+{
+	int offset;
+
+	offset = fdt_path_offset(fdt, "/");
+	/* Set the #address-cells and #size-cells values for an empty tree */
+
+	fdt_setprop_u32(fdt, offset, "#address-cells", EFI_DT_ADDR_CELLS_DEFAULT);
+	fdt_setprop_u32(fdt, offset, "#size-cells",    EFI_DT_SIZE_CELLS_DEFAULT);
+}
+
+static efi_status_t update_fdt(void *orig_fdt, unsigned long orig_fdt_size,
+			       void *fdt, int new_fdt_size, char *cmdline_ptr)
+{
+	int node, num_rsv;
+	int status;
+	u32 fdt_val32;
+	u64 fdt_val64;
+
+	/* Do some checks on provided FDT, if it exists: */
+	if (orig_fdt) {
+		if (fdt_check_header(orig_fdt)) {
+			efi_err("Device Tree header not valid!\n");
+			return EFI_LOAD_ERROR;
+		}
+		/*
+		 * We don't get the size of the FDT if we get if from a
+		 * configuration table:
+		 */
+		if (orig_fdt_size && fdt_totalsize(orig_fdt) > orig_fdt_size) {
+			efi_err("Truncated device tree! foo!\n");
+			return EFI_LOAD_ERROR;
+		}
+	}
+
+	if (orig_fdt) {
+		status = fdt_open_into(orig_fdt, fdt, new_fdt_size);
+	} else {
+		status = fdt_create_empty_tree(fdt, new_fdt_size);
+		if (status == 0) {
+			/*
+			 * Any failure from the following function is
+			 * non-critical:
+			 */
+			fdt_update_cell_size(fdt);
+		}
+	}
+
+	if (status != 0)
+		goto fdt_set_fail;
+
+	/*
+	 * Delete all memory reserve map entries. When booting via UEFI,
+	 * kernel will use the UEFI memory map to find reserved regions.
+	 */
+	num_rsv = fdt_num_mem_rsv(fdt);
+	while (num_rsv-- > 0)
+		fdt_del_mem_rsv(fdt, num_rsv);
+
+	node = fdt_subnode_offset(fdt, 0, "chosen");
+	if (node < 0) {
+		node = fdt_add_subnode(fdt, 0, "chosen");
+		if (node < 0) {
+			/* 'node' is an error code when negative: */
+			status = node;
+			goto fdt_set_fail;
+		}
+	}
+
+	if (cmdline_ptr != NULL && strlen(cmdline_ptr) > 0) {
+		status = fdt_setprop(fdt, node, "bootargs", cmdline_ptr,
+				     strlen(cmdline_ptr) + 1);
+		if (status)
+			goto fdt_set_fail;
+	}
+
+	/* Add FDT entries for EFI runtime services in chosen node. */
+	node = fdt_subnode_offset(fdt, 0, "chosen");
+	fdt_val64 = cpu_to_fdt64((u64)(unsigned long)efi_system_table);
+
+	status = fdt_setprop_var(fdt, node, "linux,uefi-system-table", fdt_val64);
+	if (status)
+		goto fdt_set_fail;
+
+	fdt_val64 = U64_MAX; /* placeholder */
+
+	status = fdt_setprop_var(fdt, node, "linux,uefi-mmap-start", fdt_val64);
+	if (status)
+		goto fdt_set_fail;
+
+	fdt_val32 = U32_MAX; /* placeholder */
+
+	status = fdt_setprop_var(fdt, node, "linux,uefi-mmap-size", fdt_val32);
+	if (status)
+		goto fdt_set_fail;
+
+	status = fdt_setprop_var(fdt, node, "linux,uefi-mmap-desc-size", fdt_val32);
+	if (status)
+		goto fdt_set_fail;
+
+	status = fdt_setprop_var(fdt, node, "linux,uefi-mmap-desc-ver", fdt_val32);
+	if (status)
+		goto fdt_set_fail;
+
+	if (IS_ENABLED(CONFIG_RANDOMIZE_BASE) && !efi_nokaslr) {
+		efi_status_t efi_status;
+
+		efi_status = efi_get_random_bytes(sizeof(fdt_val64),
+						  (u8 *)&fdt_val64);
+		if (efi_status == EFI_SUCCESS) {
+			status = fdt_setprop_var(fdt, node, "kaslr-seed", fdt_val64);
+			if (status)
+				goto fdt_set_fail;
+		}
+	}
+
+	/* Shrink the FDT back to its minimum size: */
+	fdt_pack(fdt);
+
+	return EFI_SUCCESS;
+
+fdt_set_fail:
+	if (status == -FDT_ERR_NOSPACE)
+		return EFI_BUFFER_TOO_SMALL;
+
+	return EFI_LOAD_ERROR;
+}
+
+static efi_status_t update_fdt_memmap(void *fdt, struct efi_boot_memmap *map)
+{
+	int node = fdt_path_offset(fdt, "/chosen");
+	u64 fdt_val64;
+	u32 fdt_val32;
+	int err;
+
+	if (node < 0)
+		return EFI_LOAD_ERROR;
+
+	fdt_val64 = cpu_to_fdt64((unsigned long)map->map);
+
+	err = fdt_setprop_inplace_var(fdt, node, "linux,uefi-mmap-start", fdt_val64);
+	if (err)
+		return EFI_LOAD_ERROR;
+
+	fdt_val32 = cpu_to_fdt32(map->map_size);
+
+	err = fdt_setprop_inplace_var(fdt, node, "linux,uefi-mmap-size", fdt_val32);
+	if (err)
+		return EFI_LOAD_ERROR;
+
+	fdt_val32 = cpu_to_fdt32(map->desc_size);
+
+	err = fdt_setprop_inplace_var(fdt, node, "linux,uefi-mmap-desc-size", fdt_val32);
+	if (err)
+		return EFI_LOAD_ERROR;
+
+	fdt_val32 = cpu_to_fdt32(map->desc_ver);
+
+	err = fdt_setprop_inplace_var(fdt, node, "linux,uefi-mmap-desc-ver", fdt_val32);
+	if (err)
+		return EFI_LOAD_ERROR;
+
+	return EFI_SUCCESS;
+}
+
+struct exit_boot_struct {
+	struct efi_boot_memmap	*boot_memmap;
+	efi_memory_desc_t	*runtime_map;
+	int			runtime_entry_count;
+	void			*new_fdt_addr;
+};
+
+static efi_status_t exit_boot_func(struct efi_boot_memmap *map, void *priv)
+{
+	struct exit_boot_struct *p = priv;
+
+	p->boot_memmap = map;
+
+	/*
+	 * Update the memory map with virtual addresses. The function will also
+	 * populate @runtime_map with copies of just the EFI_MEMORY_RUNTIME
+	 * entries so that we can pass it straight to SetVirtualAddressMap()
+	 */
+	efi_get_virtmap(map->map, map->map_size, map->desc_size,
+			p->runtime_map, &p->runtime_entry_count);
+
+	return update_fdt_memmap(p->new_fdt_addr, map);
+}
+
+#ifndef MAX_FDT_SIZE
+# define MAX_FDT_SIZE SZ_2M
+#endif
+
+/*
+ * Allocate memory for a new FDT, then add EFI and commandline related fields
+ * to the FDT.  This routine increases the FDT allocation size until the
+ * allocated memory is large enough.  EFI allocations are in EFI_PAGE_SIZE
+ * granules, which are fixed at 4K bytes, so in most cases the first allocation
+ * should succeed.  EFI boot services are exited at the end of this function.
+ * There must be no allocations between the get_memory_map() call and the
+ * exit_boot_services() call, so the exiting of boot services is very tightly
+ * tied to the creation of the FDT with the final memory map in it.
+ */
+static
+efi_status_t allocate_new_fdt_and_exit_boot(void *handle,
+					    efi_loaded_image_t *image,
+					    unsigned long *new_fdt_addr,
+					    char *cmdline_ptr)
+{
+	unsigned long desc_size;
+	u32 desc_ver;
+	efi_status_t status;
+	struct exit_boot_struct priv;
+	unsigned long fdt_addr = 0;
+	unsigned long fdt_size = 0;
+
+	if (!efi_novamap) {
+		status = efi_alloc_virtmap(&priv.runtime_map, &desc_size,
+					   &desc_ver);
+		if (status != EFI_SUCCESS) {
+			efi_err("Unable to retrieve UEFI memory map.\n");
+			return status;
+		}
+	}
+
+	/*
+	 * Unauthenticated device tree data is a security hazard, so ignore
+	 * 'dtb=' unless UEFI Secure Boot is disabled.  We assume that secure
+	 * boot is enabled if we can't determine its state.
+	 */
+	if (!IS_ENABLED(CONFIG_EFI_ARMSTUB_DTB_LOADER) ||
+	    efi_get_secureboot() != efi_secureboot_mode_disabled) {
+		if (strstr(cmdline_ptr, "dtb="))
+			efi_err("Ignoring DTB from command line.\n");
+	} else {
+		status = efi_load_dtb(image, &fdt_addr, &fdt_size);
+
+		if (status != EFI_SUCCESS && status != EFI_NOT_READY) {
+			efi_err("Failed to load device tree!\n");
+			goto fail;
+		}
+	}
+
+	if (fdt_addr) {
+		efi_info("Using DTB from command line\n");
+	} else {
+		/* Look for a device tree configuration table entry. */
+		fdt_addr = (uintptr_t)get_fdt(&fdt_size);
+		if (fdt_addr)
+			efi_info("Using DTB from configuration table\n");
+	}
+
+	if (!fdt_addr)
+		efi_info("Generating empty DTB\n");
+
+	efi_info("Exiting boot services...\n");
+
+	status = efi_allocate_pages(MAX_FDT_SIZE, new_fdt_addr, ULONG_MAX);
+	if (status != EFI_SUCCESS) {
+		efi_err("Unable to allocate memory for new device tree.\n");
+		goto fail;
+	}
+
+	status = update_fdt((void *)fdt_addr, fdt_size,
+			    (void *)*new_fdt_addr, MAX_FDT_SIZE, cmdline_ptr);
+
+	if (status != EFI_SUCCESS) {
+		efi_err("Unable to construct new device tree.\n");
+		goto fail_free_new_fdt;
+	}
+
+	priv.new_fdt_addr = (void *)*new_fdt_addr;
+
+	status = efi_exit_boot_services(handle, &priv, exit_boot_func);
+
+	if (status == EFI_SUCCESS) {
+		efi_set_virtual_address_map_t *svam;
+
+		if (efi_novamap)
+			return EFI_SUCCESS;
+
+		/* Install the new virtual address map */
+		svam = efi_system_table->runtime->set_virtual_address_map;
+		status = svam(priv.runtime_entry_count * desc_size, desc_size,
+			      desc_ver, priv.runtime_map);
+
+		/*
+		 * We are beyond the point of no return here, so if the call to
+		 * SetVirtualAddressMap() failed, we need to signal that to the
+		 * incoming kernel but proceed normally otherwise.
+		 */
+		if (status != EFI_SUCCESS) {
+			efi_memory_desc_t *p;
+			int l;
+
+			/*
+			 * Set the virtual address field of all
+			 * EFI_MEMORY_RUNTIME entries to U64_MAX. This will
+			 * signal the incoming kernel that no virtual
+			 * translation has been installed.
+			 */
+			for (l = 0; l < priv.boot_memmap->map_size;
+			     l += priv.boot_memmap->desc_size) {
+				p = (void *)priv.boot_memmap->map + l;
+
+				if (p->attribute & EFI_MEMORY_RUNTIME)
+					p->virt_addr = U64_MAX;
+			}
+		}
+		return EFI_SUCCESS;
+	}
+
+	efi_err("Exit boot services failed.\n");
+
+fail_free_new_fdt:
+	efi_free(MAX_FDT_SIZE, *new_fdt_addr);
+
+fail:
+	efi_free(fdt_size, fdt_addr);
+
+	efi_bs_call(free_pool, priv.runtime_map);
+
+	return EFI_LOAD_ERROR;
+}
+
+efi_status_t efi_boot_kernel(void *handle, efi_loaded_image_t *image,
+			     unsigned long kernel_addr, char *cmdline_ptr)
+{
+	unsigned long fdt_addr;
+	efi_status_t status;
+
+	status = allocate_new_fdt_and_exit_boot(handle, image, &fdt_addr,
+						cmdline_ptr);
+	if (status != EFI_SUCCESS) {
+		efi_err("Failed to update FDT and exit boot services\n");
+		return status;
+	}
+
+	if (IS_ENABLED(CONFIG_ARM))
+		efi_handle_post_ebs_state();
+
+	efi_enter_kernel(kernel_addr, fdt_addr, fdt_totalsize((void *)fdt_addr));
+	/* not reached */
+}
+
+void *get_fdt(unsigned long *fdt_size)
+{
+	void *fdt;
+
+	fdt = get_efi_config_table(DEVICE_TREE_GUID);
+
+	if (!fdt)
+		return NULL;
+
+	if (fdt_check_header(fdt) != 0) {
+		efi_err("Invalid header detected on UEFI supplied FDT, ignoring ...\n");
+		return NULL;
+	}
+	*fdt_size = fdt_totalsize(fdt);
+	return fdt;
+}
diff --git a/drivers/firmware/efi/libstub/file.c b/drivers/firmware/efi/libstub/file.c
new file mode 100644
index 000000000..f756c6139
--- /dev/null
+++ b/drivers/firmware/efi/libstub/file.c
@@ -0,0 +1,271 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Helper functions used by the EFI stub on multiple
+ * architectures. This should be #included by the EFI stub
+ * implementation files.
+ *
+ * Copyright 2011 Intel Corporation; author Matt Fleming
+ */
+
+#include <linux/efi.h>
+#include <asm/efi.h>
+
+#include "efistub.h"
+
+#define MAX_FILENAME_SIZE	256
+
+/*
+ * Some firmware implementations have problems reading files in one go.
+ * A read chunk size of 1MB seems to work for most platforms.
+ *
+ * Unfortunately, reading files in chunks triggers *other* bugs on some
+ * platforms, so we provide a way to disable this workaround, which can
+ * be done by passing "efi=nochunk" on the EFI boot stub command line.
+ *
+ * If you experience issues with initrd images being corrupt it's worth
+ * trying efi=nochunk, but chunking is enabled by default on x86 because
+ * there are far more machines that require the workaround than those that
+ * break with it enabled.
+ */
+#define EFI_READ_CHUNK_SIZE	SZ_1M
+
+struct finfo {
+	efi_file_info_t info;
+	efi_char16_t	filename[MAX_FILENAME_SIZE];
+};
+
+static efi_status_t efi_open_file(efi_file_protocol_t *volume,
+				  struct finfo *fi,
+				  efi_file_protocol_t **handle,
+				  unsigned long *file_size)
+{
+	efi_guid_t info_guid = EFI_FILE_INFO_ID;
+	efi_file_protocol_t *fh;
+	unsigned long info_sz;
+	efi_status_t status;
+
+	status = volume->open(volume, &fh, fi->filename, EFI_FILE_MODE_READ, 0);
+	if (status != EFI_SUCCESS) {
+		efi_err("Failed to open file: %ls\n", fi->filename);
+		return status;
+	}
+
+	info_sz = sizeof(struct finfo);
+	status = fh->get_info(fh, &info_guid, &info_sz, fi);
+	if (status != EFI_SUCCESS) {
+		efi_err("Failed to get file info\n");
+		fh->close(fh);
+		return status;
+	}
+
+	*handle = fh;
+	*file_size = fi->info.file_size;
+	return EFI_SUCCESS;
+}
+
+static efi_status_t efi_open_volume(efi_loaded_image_t *image,
+				    efi_file_protocol_t **fh)
+{
+	struct efi_vendor_dev_path *dp = image->file_path;
+	efi_guid_t li_proto = LOADED_IMAGE_PROTOCOL_GUID;
+	efi_guid_t fs_proto = EFI_FILE_SYSTEM_GUID;
+	efi_simple_file_system_protocol_t *io;
+	efi_status_t status;
+
+	// If we are using EFI zboot, we should look for the file system
+	// protocol on the parent image's handle instead
+	if (IS_ENABLED(CONFIG_EFI_ZBOOT) &&
+	    image->parent_handle != NULL &&
+	    dp != NULL &&
+	    dp->header.type == EFI_DEV_MEDIA &&
+	    dp->header.sub_type == EFI_DEV_MEDIA_VENDOR &&
+	    !efi_guidcmp(dp->vendorguid, LINUX_EFI_ZBOOT_MEDIA_GUID)) {
+		status = efi_bs_call(handle_protocol, image->parent_handle,
+				     &li_proto, (void *)&image);
+		if (status != EFI_SUCCESS) {
+			efi_err("Failed to locate parent image handle\n");
+			return status;
+		}
+	}
+
+	status = efi_bs_call(handle_protocol, image->device_handle, &fs_proto,
+			     (void **)&io);
+	if (status != EFI_SUCCESS) {
+		efi_err("Failed to handle fs_proto\n");
+		return status;
+	}
+
+	status = io->open_volume(io, fh);
+	if (status != EFI_SUCCESS)
+		efi_err("Failed to open volume\n");
+
+	return status;
+}
+
+static int find_file_option(const efi_char16_t *cmdline, int cmdline_len,
+			    const efi_char16_t *prefix, int prefix_size,
+			    efi_char16_t *result, int result_len)
+{
+	int prefix_len = prefix_size / 2;
+	bool found = false;
+	int i;
+
+	for (i = prefix_len; i < cmdline_len; i++) {
+		if (!memcmp(&cmdline[i - prefix_len], prefix, prefix_size)) {
+			found = true;
+			break;
+		}
+	}
+
+	if (!found)
+		return 0;
+
+	/* Skip any leading slashes */
+	while (i < cmdline_len && (cmdline[i] == L'/' || cmdline[i] == L'\\'))
+		i++;
+
+	while (--result_len > 0 && i < cmdline_len) {
+		efi_char16_t c = cmdline[i++];
+
+		if (c == L'\0' || c == L'\n' || c == L' ')
+			break;
+		else if (c == L'/')
+			/* Replace UNIX dir separators with EFI standard ones */
+			*result++ = L'\\';
+		else
+			*result++ = c;
+	}
+	*result = L'\0';
+	return i;
+}
+
+/*
+ * Check the cmdline for a LILO-style file= arguments.
+ *
+ * We only support loading a file from the same filesystem as
+ * the kernel image.
+ */
+efi_status_t handle_cmdline_files(efi_loaded_image_t *image,
+				  const efi_char16_t *optstr,
+				  int optstr_size,
+				  unsigned long soft_limit,
+				  unsigned long hard_limit,
+				  unsigned long *load_addr,
+				  unsigned long *load_size)
+{
+	const efi_char16_t *cmdline = image->load_options;
+	u32 cmdline_len = image->load_options_size;
+	unsigned long efi_chunk_size = ULONG_MAX;
+	efi_file_protocol_t *volume = NULL;
+	efi_file_protocol_t *file;
+	unsigned long alloc_addr;
+	unsigned long alloc_size;
+	efi_status_t status;
+	int offset;
+
+	if (!load_addr || !load_size)
+		return EFI_INVALID_PARAMETER;
+
+	efi_apply_loadoptions_quirk((const void **)&cmdline, &cmdline_len);
+	cmdline_len /= sizeof(*cmdline);
+
+	if (IS_ENABLED(CONFIG_X86) && !efi_nochunk)
+		efi_chunk_size = EFI_READ_CHUNK_SIZE;
+
+	alloc_addr = alloc_size = 0;
+	do {
+		struct finfo fi;
+		unsigned long size;
+		void *addr;
+
+		offset = find_file_option(cmdline, cmdline_len,
+					  optstr, optstr_size,
+					  fi.filename, ARRAY_SIZE(fi.filename));
+
+		if (!offset)
+			break;
+
+		cmdline += offset;
+		cmdline_len -= offset;
+
+		if (!volume) {
+			status = efi_open_volume(image, &volume);
+			if (status != EFI_SUCCESS)
+				return status;
+		}
+
+		status = efi_open_file(volume, &fi, &file, &size);
+		if (status != EFI_SUCCESS)
+			goto err_close_volume;
+
+		/*
+		 * Check whether the existing allocation can contain the next
+		 * file. This condition will also trigger naturally during the
+		 * first (and typically only) iteration of the loop, given that
+		 * alloc_size == 0 in that case.
+		 */
+		if (round_up(alloc_size + size, EFI_ALLOC_ALIGN) >
+		    round_up(alloc_size, EFI_ALLOC_ALIGN)) {
+			unsigned long old_addr = alloc_addr;
+
+			status = EFI_OUT_OF_RESOURCES;
+			if (soft_limit < hard_limit)
+				status = efi_allocate_pages(alloc_size + size,
+							    &alloc_addr,
+							    soft_limit);
+			if (status == EFI_OUT_OF_RESOURCES)
+				status = efi_allocate_pages(alloc_size + size,
+							    &alloc_addr,
+							    hard_limit);
+			if (status != EFI_SUCCESS) {
+				efi_err("Failed to allocate memory for files\n");
+				goto err_close_file;
+			}
+
+			if (old_addr != 0) {
+				/*
+				 * This is not the first time we've gone
+				 * around this loop, and so we are loading
+				 * multiple files that need to be concatenated
+				 * and returned in a single buffer.
+				 */
+				memcpy((void *)alloc_addr, (void *)old_addr, alloc_size);
+				efi_free(alloc_size, old_addr);
+			}
+		}
+
+		addr = (void *)alloc_addr + alloc_size;
+		alloc_size += size;
+
+		while (size) {
+			unsigned long chunksize = min(size, efi_chunk_size);
+
+			status = file->read(file, &chunksize, addr);
+			if (status != EFI_SUCCESS) {
+				efi_err("Failed to read file\n");
+				goto err_close_file;
+			}
+			addr += chunksize;
+			size -= chunksize;
+		}
+		file->close(file);
+	} while (offset > 0);
+
+	*load_addr = alloc_addr;
+	*load_size = alloc_size;
+
+	if (volume)
+		volume->close(volume);
+
+	if (*load_size == 0)
+		return EFI_NOT_READY;
+	return EFI_SUCCESS;
+
+err_close_file:
+	file->close(file);
+
+err_close_volume:
+	volume->close(volume);
+	efi_free(alloc_size, alloc_addr);
+	return status;
+}
diff --git a/drivers/firmware/efi/libstub/gop.c b/drivers/firmware/efi/libstub/gop.c
new file mode 100644
index 000000000..ea5da307d
--- /dev/null
+++ b/drivers/firmware/efi/libstub/gop.c
@@ -0,0 +1,580 @@
+// SPDX-License-Identifier: GPL-2.0
+/* -----------------------------------------------------------------------
+ *
+ *   Copyright 2011 Intel Corporation; author Matt Fleming
+ *
+ * ----------------------------------------------------------------------- */
+
+#include <linux/bitops.h>
+#include <linux/ctype.h>
+#include <linux/efi.h>
+#include <linux/screen_info.h>
+#include <linux/string.h>
+#include <asm/efi.h>
+#include <asm/setup.h>
+
+#include "efistub.h"
+
+enum efi_cmdline_option {
+	EFI_CMDLINE_NONE,
+	EFI_CMDLINE_MODE_NUM,
+	EFI_CMDLINE_RES,
+	EFI_CMDLINE_AUTO,
+	EFI_CMDLINE_LIST
+};
+
+static struct {
+	enum efi_cmdline_option option;
+	union {
+		u32 mode;
+		struct {
+			u32 width, height;
+			int format;
+			u8 depth;
+		} res;
+	};
+} cmdline = { .option = EFI_CMDLINE_NONE };
+
+static bool parse_modenum(char *option, char **next)
+{
+	u32 m;
+
+	if (!strstarts(option, "mode="))
+		return false;
+	option += strlen("mode=");
+	m = simple_strtoull(option, &option, 0);
+	if (*option && *option++ != ',')
+		return false;
+	cmdline.option = EFI_CMDLINE_MODE_NUM;
+	cmdline.mode   = m;
+
+	*next = option;
+	return true;
+}
+
+static bool parse_res(char *option, char **next)
+{
+	u32 w, h, d = 0;
+	int pf = -1;
+
+	if (!isdigit(*option))
+		return false;
+	w = simple_strtoull(option, &option, 10);
+	if (*option++ != 'x' || !isdigit(*option))
+		return false;
+	h = simple_strtoull(option, &option, 10);
+	if (*option == '-') {
+		option++;
+		if (strstarts(option, "rgb")) {
+			option += strlen("rgb");
+			pf = PIXEL_RGB_RESERVED_8BIT_PER_COLOR;
+		} else if (strstarts(option, "bgr")) {
+			option += strlen("bgr");
+			pf = PIXEL_BGR_RESERVED_8BIT_PER_COLOR;
+		} else if (isdigit(*option))
+			d = simple_strtoull(option, &option, 10);
+		else
+			return false;
+	}
+	if (*option && *option++ != ',')
+		return false;
+	cmdline.option     = EFI_CMDLINE_RES;
+	cmdline.res.width  = w;
+	cmdline.res.height = h;
+	cmdline.res.format = pf;
+	cmdline.res.depth  = d;
+
+	*next = option;
+	return true;
+}
+
+static bool parse_auto(char *option, char **next)
+{
+	if (!strstarts(option, "auto"))
+		return false;
+	option += strlen("auto");
+	if (*option && *option++ != ',')
+		return false;
+	cmdline.option = EFI_CMDLINE_AUTO;
+
+	*next = option;
+	return true;
+}
+
+static bool parse_list(char *option, char **next)
+{
+	if (!strstarts(option, "list"))
+		return false;
+	option += strlen("list");
+	if (*option && *option++ != ',')
+		return false;
+	cmdline.option = EFI_CMDLINE_LIST;
+
+	*next = option;
+	return true;
+}
+
+void efi_parse_option_graphics(char *option)
+{
+	while (*option) {
+		if (parse_modenum(option, &option))
+			continue;
+		if (parse_res(option, &option))
+			continue;
+		if (parse_auto(option, &option))
+			continue;
+		if (parse_list(option, &option))
+			continue;
+
+		while (*option && *option++ != ',')
+			;
+	}
+}
+
+static u32 choose_mode_modenum(efi_graphics_output_protocol_t *gop)
+{
+	efi_status_t status;
+
+	efi_graphics_output_protocol_mode_t *mode;
+	efi_graphics_output_mode_info_t *info;
+	unsigned long info_size;
+
+	u32 max_mode, cur_mode;
+	int pf;
+
+	mode = efi_table_attr(gop, mode);
+
+	cur_mode = efi_table_attr(mode, mode);
+	if (cmdline.mode == cur_mode)
+		return cur_mode;
+
+	max_mode = efi_table_attr(mode, max_mode);
+	if (cmdline.mode >= max_mode) {
+		efi_err("Requested mode is invalid\n");
+		return cur_mode;
+	}
+
+	status = efi_call_proto(gop, query_mode, cmdline.mode,
+				&info_size, &info);
+	if (status != EFI_SUCCESS) {
+		efi_err("Couldn't get mode information\n");
+		return cur_mode;
+	}
+
+	pf = info->pixel_format;
+
+	efi_bs_call(free_pool, info);
+
+	if (pf == PIXEL_BLT_ONLY || pf >= PIXEL_FORMAT_MAX) {
+		efi_err("Invalid PixelFormat\n");
+		return cur_mode;
+	}
+
+	return cmdline.mode;
+}
+
+static u8 pixel_bpp(int pixel_format, efi_pixel_bitmask_t pixel_info)
+{
+	if (pixel_format == PIXEL_BIT_MASK) {
+		u32 mask = pixel_info.red_mask | pixel_info.green_mask |
+			   pixel_info.blue_mask | pixel_info.reserved_mask;
+		if (!mask)
+			return 0;
+		return __fls(mask) - __ffs(mask) + 1;
+	} else
+		return 32;
+}
+
+static u32 choose_mode_res(efi_graphics_output_protocol_t *gop)
+{
+	efi_status_t status;
+
+	efi_graphics_output_protocol_mode_t *mode;
+	efi_graphics_output_mode_info_t *info;
+	unsigned long info_size;
+
+	u32 max_mode, cur_mode;
+	int pf;
+	efi_pixel_bitmask_t pi;
+	u32 m, w, h;
+
+	mode = efi_table_attr(gop, mode);
+
+	cur_mode = efi_table_attr(mode, mode);
+	info = efi_table_attr(mode, info);
+	pf = info->pixel_format;
+	pi = info->pixel_information;
+	w  = info->horizontal_resolution;
+	h  = info->vertical_resolution;
+
+	if (w == cmdline.res.width && h == cmdline.res.height &&
+	    (cmdline.res.format < 0 || cmdline.res.format == pf) &&
+	    (!cmdline.res.depth || cmdline.res.depth == pixel_bpp(pf, pi)))
+		return cur_mode;
+
+	max_mode = efi_table_attr(mode, max_mode);
+
+	for (m = 0; m < max_mode; m++) {
+		if (m == cur_mode)
+			continue;
+
+		status = efi_call_proto(gop, query_mode, m,
+					&info_size, &info);
+		if (status != EFI_SUCCESS)
+			continue;
+
+		pf = info->pixel_format;
+		pi = info->pixel_information;
+		w  = info->horizontal_resolution;
+		h  = info->vertical_resolution;
+
+		efi_bs_call(free_pool, info);
+
+		if (pf == PIXEL_BLT_ONLY || pf >= PIXEL_FORMAT_MAX)
+			continue;
+		if (w == cmdline.res.width && h == cmdline.res.height &&
+		    (cmdline.res.format < 0 || cmdline.res.format == pf) &&
+		    (!cmdline.res.depth || cmdline.res.depth == pixel_bpp(pf, pi)))
+			return m;
+	}
+
+	efi_err("Couldn't find requested mode\n");
+
+	return cur_mode;
+}
+
+static u32 choose_mode_auto(efi_graphics_output_protocol_t *gop)
+{
+	efi_status_t status;
+
+	efi_graphics_output_protocol_mode_t *mode;
+	efi_graphics_output_mode_info_t *info;
+	unsigned long info_size;
+
+	u32 max_mode, cur_mode, best_mode, area;
+	u8 depth;
+	int pf;
+	efi_pixel_bitmask_t pi;
+	u32 m, w, h, a;
+	u8 d;
+
+	mode = efi_table_attr(gop, mode);
+
+	cur_mode = efi_table_attr(mode, mode);
+	max_mode = efi_table_attr(mode, max_mode);
+
+	info = efi_table_attr(mode, info);
+
+	pf = info->pixel_format;
+	pi = info->pixel_information;
+	w  = info->horizontal_resolution;
+	h  = info->vertical_resolution;
+
+	best_mode = cur_mode;
+	area = w * h;
+	depth = pixel_bpp(pf, pi);
+
+	for (m = 0; m < max_mode; m++) {
+		if (m == cur_mode)
+			continue;
+
+		status = efi_call_proto(gop, query_mode, m,
+					&info_size, &info);
+		if (status != EFI_SUCCESS)
+			continue;
+
+		pf = info->pixel_format;
+		pi = info->pixel_information;
+		w  = info->horizontal_resolution;
+		h  = info->vertical_resolution;
+
+		efi_bs_call(free_pool, info);
+
+		if (pf == PIXEL_BLT_ONLY || pf >= PIXEL_FORMAT_MAX)
+			continue;
+		a = w * h;
+		if (a < area)
+			continue;
+		d = pixel_bpp(pf, pi);
+		if (a > area || d > depth) {
+			best_mode = m;
+			area = a;
+			depth = d;
+		}
+	}
+
+	return best_mode;
+}
+
+static u32 choose_mode_list(efi_graphics_output_protocol_t *gop)
+{
+	efi_status_t status;
+
+	efi_graphics_output_protocol_mode_t *mode;
+	efi_graphics_output_mode_info_t *info;
+	unsigned long info_size;
+
+	u32 max_mode, cur_mode;
+	int pf;
+	efi_pixel_bitmask_t pi;
+	u32 m, w, h;
+	u8 d;
+	const char *dstr;
+	bool valid;
+	efi_input_key_t key;
+
+	mode = efi_table_attr(gop, mode);
+
+	cur_mode = efi_table_attr(mode, mode);
+	max_mode = efi_table_attr(mode, max_mode);
+
+	efi_printk("Available graphics modes are 0-%u\n", max_mode-1);
+	efi_puts("  * = current mode\n"
+		 "  - = unusable mode\n");
+	for (m = 0; m < max_mode; m++) {
+		status = efi_call_proto(gop, query_mode, m,
+					&info_size, &info);
+		if (status != EFI_SUCCESS)
+			continue;
+
+		pf = info->pixel_format;
+		pi = info->pixel_information;
+		w  = info->horizontal_resolution;
+		h  = info->vertical_resolution;
+
+		efi_bs_call(free_pool, info);
+
+		valid = !(pf == PIXEL_BLT_ONLY || pf >= PIXEL_FORMAT_MAX);
+		d = 0;
+		switch (pf) {
+		case PIXEL_RGB_RESERVED_8BIT_PER_COLOR:
+			dstr = "rgb";
+			break;
+		case PIXEL_BGR_RESERVED_8BIT_PER_COLOR:
+			dstr = "bgr";
+			break;
+		case PIXEL_BIT_MASK:
+			dstr = "";
+			d = pixel_bpp(pf, pi);
+			break;
+		case PIXEL_BLT_ONLY:
+			dstr = "blt";
+			break;
+		default:
+			dstr = "xxx";
+			break;
+		}
+
+		efi_printk("Mode %3u %c%c: Resolution %ux%u-%s%.0hhu\n",
+			   m,
+			   m == cur_mode ? '*' : ' ',
+			   !valid ? '-' : ' ',
+			   w, h, dstr, d);
+	}
+
+	efi_puts("\nPress any key to continue (or wait 10 seconds)\n");
+	status = efi_wait_for_key(10 * EFI_USEC_PER_SEC, &key);
+	if (status != EFI_SUCCESS && status != EFI_TIMEOUT) {
+		efi_err("Unable to read key, continuing in 10 seconds\n");
+		efi_bs_call(stall, 10 * EFI_USEC_PER_SEC);
+	}
+
+	return cur_mode;
+}
+
+static void set_mode(efi_graphics_output_protocol_t *gop)
+{
+	efi_graphics_output_protocol_mode_t *mode;
+	u32 cur_mode, new_mode;
+
+	switch (cmdline.option) {
+	case EFI_CMDLINE_MODE_NUM:
+		new_mode = choose_mode_modenum(gop);
+		break;
+	case EFI_CMDLINE_RES:
+		new_mode = choose_mode_res(gop);
+		break;
+	case EFI_CMDLINE_AUTO:
+		new_mode = choose_mode_auto(gop);
+		break;
+	case EFI_CMDLINE_LIST:
+		new_mode = choose_mode_list(gop);
+		break;
+	default:
+		return;
+	}
+
+	mode = efi_table_attr(gop, mode);
+	cur_mode = efi_table_attr(mode, mode);
+
+	if (new_mode == cur_mode)
+		return;
+
+	if (efi_call_proto(gop, set_mode, new_mode) != EFI_SUCCESS)
+		efi_err("Failed to set requested mode\n");
+}
+
+static void find_bits(u32 mask, u8 *pos, u8 *size)
+{
+	if (!mask) {
+		*pos = *size = 0;
+		return;
+	}
+
+	/* UEFI spec guarantees that the set bits are contiguous */
+	*pos  = __ffs(mask);
+	*size = __fls(mask) - *pos + 1;
+}
+
+static void
+setup_pixel_info(struct screen_info *si, u32 pixels_per_scan_line,
+		 efi_pixel_bitmask_t pixel_info, int pixel_format)
+{
+	if (pixel_format == PIXEL_BIT_MASK) {
+		find_bits(pixel_info.red_mask,
+			  &si->red_pos, &si->red_size);
+		find_bits(pixel_info.green_mask,
+			  &si->green_pos, &si->green_size);
+		find_bits(pixel_info.blue_mask,
+			  &si->blue_pos, &si->blue_size);
+		find_bits(pixel_info.reserved_mask,
+			  &si->rsvd_pos, &si->rsvd_size);
+		si->lfb_depth = si->red_size + si->green_size +
+			si->blue_size + si->rsvd_size;
+		si->lfb_linelength = (pixels_per_scan_line * si->lfb_depth) / 8;
+	} else {
+		if (pixel_format == PIXEL_RGB_RESERVED_8BIT_PER_COLOR) {
+			si->red_pos   = 0;
+			si->blue_pos  = 16;
+		} else /* PIXEL_BGR_RESERVED_8BIT_PER_COLOR */ {
+			si->blue_pos  = 0;
+			si->red_pos   = 16;
+		}
+
+		si->green_pos = 8;
+		si->rsvd_pos  = 24;
+		si->red_size = si->green_size =
+			si->blue_size = si->rsvd_size = 8;
+
+		si->lfb_depth = 32;
+		si->lfb_linelength = pixels_per_scan_line * 4;
+	}
+}
+
+static efi_graphics_output_protocol_t *
+find_gop(efi_guid_t *proto, unsigned long size, void **handles)
+{
+	efi_graphics_output_protocol_t *first_gop;
+	efi_handle_t h;
+	int i;
+
+	first_gop = NULL;
+
+	for_each_efi_handle(h, handles, size, i) {
+		efi_status_t status;
+
+		efi_graphics_output_protocol_t *gop;
+		efi_graphics_output_protocol_mode_t *mode;
+		efi_graphics_output_mode_info_t *info;
+
+		efi_guid_t conout_proto = EFI_CONSOLE_OUT_DEVICE_GUID;
+		void *dummy = NULL;
+
+		status = efi_bs_call(handle_protocol, h, proto, (void **)&gop);
+		if (status != EFI_SUCCESS)
+			continue;
+
+		mode = efi_table_attr(gop, mode);
+		info = efi_table_attr(mode, info);
+		if (info->pixel_format == PIXEL_BLT_ONLY ||
+		    info->pixel_format >= PIXEL_FORMAT_MAX)
+			continue;
+
+		/*
+		 * Systems that use the UEFI Console Splitter may
+		 * provide multiple GOP devices, not all of which are
+		 * backed by real hardware. The workaround is to search
+		 * for a GOP implementing the ConOut protocol, and if
+		 * one isn't found, to just fall back to the first GOP.
+		 *
+		 * Once we've found a GOP supporting ConOut,
+		 * don't bother looking any further.
+		 */
+		status = efi_bs_call(handle_protocol, h, &conout_proto, &dummy);
+		if (status == EFI_SUCCESS)
+			return gop;
+
+		if (!first_gop)
+			first_gop = gop;
+	}
+
+	return first_gop;
+}
+
+static efi_status_t setup_gop(struct screen_info *si, efi_guid_t *proto,
+			      unsigned long size, void **handles)
+{
+	efi_graphics_output_protocol_t *gop;
+	efi_graphics_output_protocol_mode_t *mode;
+	efi_graphics_output_mode_info_t *info;
+
+	gop = find_gop(proto, size, handles);
+
+	/* Did we find any GOPs? */
+	if (!gop)
+		return EFI_NOT_FOUND;
+
+	/* Change mode if requested */
+	set_mode(gop);
+
+	/* EFI framebuffer */
+	mode = efi_table_attr(gop, mode);
+	info = efi_table_attr(mode, info);
+
+	si->orig_video_isVGA = VIDEO_TYPE_EFI;
+
+	si->lfb_width  = info->horizontal_resolution;
+	si->lfb_height = info->vertical_resolution;
+
+	efi_set_u64_split(efi_table_attr(mode, frame_buffer_base),
+			  &si->lfb_base, &si->ext_lfb_base);
+	if (si->ext_lfb_base)
+		si->capabilities |= VIDEO_CAPABILITY_64BIT_BASE;
+
+	si->pages = 1;
+
+	setup_pixel_info(si, info->pixels_per_scan_line,
+			     info->pixel_information, info->pixel_format);
+
+	si->lfb_size = si->lfb_linelength * si->lfb_height;
+
+	si->capabilities |= VIDEO_CAPABILITY_SKIP_QUIRKS;
+
+	return EFI_SUCCESS;
+}
+
+/*
+ * See if we have Graphics Output Protocol
+ */
+efi_status_t efi_setup_gop(struct screen_info *si, efi_guid_t *proto,
+			   unsigned long size)
+{
+	efi_status_t status;
+	void **gop_handle = NULL;
+
+	status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, size,
+			     (void **)&gop_handle);
+	if (status != EFI_SUCCESS)
+		return status;
+
+	status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL, proto, NULL,
+			     &size, gop_handle);
+	if (status != EFI_SUCCESS)
+		goto free_handle;
+
+	status = setup_gop(si, proto, size, gop_handle);
+
+free_handle:
+	efi_bs_call(free_pool, gop_handle);
+	return status;
+}
diff --git a/drivers/firmware/efi/libstub/intrinsics.c b/drivers/firmware/efi/libstub/intrinsics.c
new file mode 100644
index 000000000..a04ab3929
--- /dev/null
+++ b/drivers/firmware/efi/libstub/intrinsics.c
@@ -0,0 +1,30 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/efi.h>
+#include <asm/efi.h>
+#include <asm/string.h>
+
+#include "efistub.h"
+
+#ifdef CONFIG_KASAN
+#undef memcpy
+#undef memmove
+#undef memset
+void *__memcpy(void *__dest, const void *__src, size_t __n) __alias(memcpy);
+void *__memmove(void *__dest, const void *__src, size_t count) __alias(memmove);
+void *__memset(void *s, int c, size_t count) __alias(memset);
+#endif
+
+void *memcpy(void *dst, const void *src, size_t len)
+{
+	efi_bs_call(copy_mem, dst, src, len);
+	return dst;
+}
+
+extern void *memmove(void *dst, const void *src, size_t len) __alias(memcpy);
+
+void *memset(void *dst, int c, size_t len)
+{
+	efi_bs_call(set_mem, dst, len, c & U8_MAX);
+	return dst;
+}
diff --git a/drivers/firmware/efi/libstub/loongarch-stub.c b/drivers/firmware/efi/libstub/loongarch-stub.c
new file mode 100644
index 000000000..32329f2a9
--- /dev/null
+++ b/drivers/firmware/efi/libstub/loongarch-stub.c
@@ -0,0 +1,102 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Author: Yun Liu <liuyun@loongson.cn>
+ *         Huacai Chen <chenhuacai@loongson.cn>
+ * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
+ */
+
+#include <asm/efi.h>
+#include <asm/addrspace.h>
+#include "efistub.h"
+
+typedef void __noreturn (*kernel_entry_t)(bool efi, unsigned long cmdline,
+					  unsigned long systab);
+
+extern int kernel_asize;
+extern int kernel_fsize;
+extern int kernel_offset;
+extern kernel_entry_t kernel_entry;
+
+efi_status_t check_platform_features(void)
+{
+	return EFI_SUCCESS;
+}
+
+efi_status_t handle_kernel_image(unsigned long *image_addr,
+				 unsigned long *image_size,
+				 unsigned long *reserve_addr,
+				 unsigned long *reserve_size,
+				 efi_loaded_image_t *image,
+				 efi_handle_t image_handle)
+{
+	efi_status_t status;
+	unsigned long kernel_addr = 0;
+
+	kernel_addr = (unsigned long)&kernel_offset - kernel_offset;
+
+	status = efi_relocate_kernel(&kernel_addr, kernel_fsize, kernel_asize,
+				     PHYSADDR(VMLINUX_LOAD_ADDRESS), SZ_2M, 0x0);
+
+	*image_addr = kernel_addr;
+	*image_size = kernel_asize;
+
+	return status;
+}
+
+struct exit_boot_struct {
+	efi_memory_desc_t	*runtime_map;
+	int			runtime_entry_count;
+};
+
+static efi_status_t exit_boot_func(struct efi_boot_memmap *map, void *priv)
+{
+	struct exit_boot_struct *p = priv;
+
+	/*
+	 * Update the memory map with virtual addresses. The function will also
+	 * populate @runtime_map with copies of just the EFI_MEMORY_RUNTIME
+	 * entries so that we can pass it straight to SetVirtualAddressMap()
+	 */
+	efi_get_virtmap(map->map, map->map_size, map->desc_size,
+			p->runtime_map, &p->runtime_entry_count);
+
+	return EFI_SUCCESS;
+}
+
+efi_status_t efi_boot_kernel(void *handle, efi_loaded_image_t *image,
+			     unsigned long kernel_addr, char *cmdline_ptr)
+{
+	kernel_entry_t real_kernel_entry;
+	struct exit_boot_struct priv;
+	unsigned long desc_size;
+	efi_status_t status;
+	u32 desc_ver;
+
+	status = efi_alloc_virtmap(&priv.runtime_map, &desc_size, &desc_ver);
+	if (status != EFI_SUCCESS) {
+		efi_err("Unable to retrieve UEFI memory map.\n");
+		return status;
+	}
+
+	efi_info("Exiting boot services\n");
+
+	efi_novamap = false;
+	status = efi_exit_boot_services(handle, &priv, exit_boot_func);
+	if (status != EFI_SUCCESS)
+		return status;
+
+	/* Install the new virtual address map */
+	efi_rt_call(set_virtual_address_map,
+		    priv.runtime_entry_count * desc_size, desc_size,
+		    desc_ver, priv.runtime_map);
+
+	/* Config Direct Mapping */
+	csr_write64(CSR_DMW0_INIT, LOONGARCH_CSR_DMWIN0);
+	csr_write64(CSR_DMW1_INIT, LOONGARCH_CSR_DMWIN1);
+
+	real_kernel_entry = (kernel_entry_t)
+		((unsigned long)&kernel_entry - kernel_addr + VMLINUX_LOAD_ADDRESS);
+
+	real_kernel_entry(true, (unsigned long)cmdline_ptr,
+			  (unsigned long)efi_system_table);
+}
diff --git a/drivers/firmware/efi/libstub/mem.c b/drivers/firmware/efi/libstub/mem.c
new file mode 100644
index 000000000..45841ef55
--- /dev/null
+++ b/drivers/firmware/efi/libstub/mem.c
@@ -0,0 +1,127 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/efi.h>
+#include <asm/efi.h>
+
+#include "efistub.h"
+
+/**
+ * efi_get_memory_map() - get memory map
+ * @map:		pointer to memory map pointer to which to assign the
+ *			newly allocated memory map
+ * @install_cfg_tbl:	whether or not to install the boot memory map as a
+ *			configuration table
+ *
+ * Retrieve the UEFI memory map. The allocated memory leaves room for
+ * up to EFI_MMAP_NR_SLACK_SLOTS additional memory map entries.
+ *
+ * Return:	status code
+ */
+efi_status_t efi_get_memory_map(struct efi_boot_memmap **map,
+				bool install_cfg_tbl)
+{
+	int memtype = install_cfg_tbl ? EFI_ACPI_RECLAIM_MEMORY
+				      : EFI_LOADER_DATA;
+	efi_guid_t tbl_guid = LINUX_EFI_BOOT_MEMMAP_GUID;
+	struct efi_boot_memmap *m, tmp;
+	efi_status_t status;
+	unsigned long size;
+
+	tmp.map_size = 0;
+	status = efi_bs_call(get_memory_map, &tmp.map_size, NULL, &tmp.map_key,
+			     &tmp.desc_size, &tmp.desc_ver);
+	if (status != EFI_BUFFER_TOO_SMALL)
+		return EFI_LOAD_ERROR;
+
+	size = tmp.map_size + tmp.desc_size * EFI_MMAP_NR_SLACK_SLOTS;
+	status = efi_bs_call(allocate_pool, memtype, sizeof(*m) + size,
+			     (void **)&m);
+	if (status != EFI_SUCCESS)
+		return status;
+
+	if (install_cfg_tbl) {
+		/*
+		 * Installing a configuration table might allocate memory, and
+		 * this may modify the memory map. This means we should install
+		 * the configuration table first, and re-install or delete it
+		 * as needed.
+		 */
+		status = efi_bs_call(install_configuration_table, &tbl_guid, m);
+		if (status != EFI_SUCCESS)
+			goto free_map;
+	}
+
+	m->buff_size = m->map_size = size;
+	status = efi_bs_call(get_memory_map, &m->map_size, m->map, &m->map_key,
+			     &m->desc_size, &m->desc_ver);
+	if (status != EFI_SUCCESS)
+		goto uninstall_table;
+
+	*map = m;
+	return EFI_SUCCESS;
+
+uninstall_table:
+	if (install_cfg_tbl)
+		efi_bs_call(install_configuration_table, &tbl_guid, NULL);
+free_map:
+	efi_bs_call(free_pool, m);
+	return status;
+}
+
+/**
+ * efi_allocate_pages() - Allocate memory pages
+ * @size:	minimum number of bytes to allocate
+ * @addr:	On return the address of the first allocated page. The first
+ *		allocated page has alignment EFI_ALLOC_ALIGN which is an
+ *		architecture dependent multiple of the page size.
+ * @max:	the address that the last allocated memory page shall not
+ *		exceed
+ *
+ * Allocate pages as EFI_LOADER_DATA. The allocated pages are aligned according
+ * to EFI_ALLOC_ALIGN. The last allocated page will not exceed the address
+ * given by @max.
+ *
+ * Return:	status code
+ */
+efi_status_t efi_allocate_pages(unsigned long size, unsigned long *addr,
+				unsigned long max)
+{
+	efi_physical_addr_t alloc_addr;
+	efi_status_t status;
+
+	if (EFI_ALLOC_ALIGN > EFI_PAGE_SIZE)
+		return efi_allocate_pages_aligned(size, addr, max,
+						  EFI_ALLOC_ALIGN);
+
+	alloc_addr = ALIGN_DOWN(max + 1, EFI_ALLOC_ALIGN) - 1;
+	status = efi_bs_call(allocate_pages, EFI_ALLOCATE_MAX_ADDRESS,
+			     EFI_LOADER_DATA, DIV_ROUND_UP(size, EFI_PAGE_SIZE),
+			     &alloc_addr);
+	if (status != EFI_SUCCESS)
+		return status;
+
+	*addr = alloc_addr;
+	return EFI_SUCCESS;
+}
+
+/**
+ * efi_free() - free memory pages
+ * @size:	size of the memory area to free in bytes
+ * @addr:	start of the memory area to free (must be EFI_PAGE_SIZE
+ *		aligned)
+ *
+ * @size is rounded up to a multiple of EFI_ALLOC_ALIGN which is an
+ * architecture specific multiple of EFI_PAGE_SIZE. So this function should
+ * only be used to return pages allocated with efi_allocate_pages() or
+ * efi_low_alloc_above().
+ */
+void efi_free(unsigned long size, unsigned long addr)
+{
+	unsigned long nr_pages;
+
+	if (!size)
+		return;
+
+	nr_pages = round_up(size, EFI_ALLOC_ALIGN) / EFI_PAGE_SIZE;
+	efi_bs_call(free_pages, addr, nr_pages);
+}
diff --git a/drivers/firmware/efi/libstub/pci.c b/drivers/firmware/efi/libstub/pci.c
new file mode 100644
index 000000000..99fb25d2b
--- /dev/null
+++ b/drivers/firmware/efi/libstub/pci.c
@@ -0,0 +1,114 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * PCI-related functions used by the EFI stub on multiple
+ * architectures.
+ *
+ * Copyright 2019 Google, LLC
+ */
+
+#include <linux/efi.h>
+#include <linux/pci.h>
+
+#include <asm/efi.h>
+
+#include "efistub.h"
+
+void efi_pci_disable_bridge_busmaster(void)
+{
+	efi_guid_t pci_proto = EFI_PCI_IO_PROTOCOL_GUID;
+	unsigned long pci_handle_size = 0;
+	efi_handle_t *pci_handle = NULL;
+	efi_handle_t handle;
+	efi_status_t status;
+	u16 class, command;
+	int i;
+
+	status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL, &pci_proto,
+			     NULL, &pci_handle_size, NULL);
+
+	if (status != EFI_BUFFER_TOO_SMALL) {
+		if (status != EFI_SUCCESS && status != EFI_NOT_FOUND)
+			efi_err("Failed to locate PCI I/O handles'\n");
+		return;
+	}
+
+	status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, pci_handle_size,
+			     (void **)&pci_handle);
+	if (status != EFI_SUCCESS) {
+		efi_err("Failed to allocate memory for 'pci_handle'\n");
+		return;
+	}
+
+	status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL, &pci_proto,
+			     NULL, &pci_handle_size, pci_handle);
+	if (status != EFI_SUCCESS) {
+		efi_err("Failed to locate PCI I/O handles'\n");
+		goto free_handle;
+	}
+
+	for_each_efi_handle(handle, pci_handle, pci_handle_size, i) {
+		efi_pci_io_protocol_t *pci;
+		unsigned long segment_nr, bus_nr, device_nr, func_nr;
+
+		status = efi_bs_call(handle_protocol, handle, &pci_proto,
+				     (void **)&pci);
+		if (status != EFI_SUCCESS)
+			continue;
+
+		/*
+		 * Disregard devices living on bus 0 - these are not behind a
+		 * bridge so no point in disconnecting them from their drivers.
+		 */
+		status = efi_call_proto(pci, get_location, &segment_nr, &bus_nr,
+					&device_nr, &func_nr);
+		if (status != EFI_SUCCESS || bus_nr == 0)
+			continue;
+
+		/*
+		 * Don't disconnect VGA controllers so we don't risk losing
+		 * access to the framebuffer. Drivers for true PCIe graphics
+		 * controllers that are behind a PCIe root port do not use
+		 * DMA to implement the GOP framebuffer anyway [although they
+		 * may use it in their implementation of Gop->Blt()], and so
+		 * disabling DMA in the PCI bridge should not interfere with
+		 * normal operation of the device.
+		 */
+		status = efi_call_proto(pci, pci.read, EfiPciIoWidthUint16,
+					PCI_CLASS_DEVICE, 1, &class);
+		if (status != EFI_SUCCESS || class == PCI_CLASS_DISPLAY_VGA)
+			continue;
+
+		/* Disconnect this handle from all its drivers */
+		efi_bs_call(disconnect_controller, handle, NULL, NULL);
+	}
+
+	for_each_efi_handle(handle, pci_handle, pci_handle_size, i) {
+		efi_pci_io_protocol_t *pci;
+
+		status = efi_bs_call(handle_protocol, handle, &pci_proto,
+				     (void **)&pci);
+		if (status != EFI_SUCCESS || !pci)
+			continue;
+
+		status = efi_call_proto(pci, pci.read, EfiPciIoWidthUint16,
+					PCI_CLASS_DEVICE, 1, &class);
+
+		if (status != EFI_SUCCESS || class != PCI_CLASS_BRIDGE_PCI)
+			continue;
+
+		/* Disable busmastering */
+		status = efi_call_proto(pci, pci.read, EfiPciIoWidthUint16,
+					PCI_COMMAND, 1, &command);
+		if (status != EFI_SUCCESS || !(command & PCI_COMMAND_MASTER))
+			continue;
+
+		command &= ~PCI_COMMAND_MASTER;
+		status = efi_call_proto(pci, pci.write, EfiPciIoWidthUint16,
+					PCI_COMMAND, 1, &command);
+		if (status != EFI_SUCCESS)
+			efi_err("Failed to disable PCI busmastering\n");
+	}
+
+free_handle:
+	efi_bs_call(free_pool, pci_handle);
+}
diff --git a/drivers/firmware/efi/libstub/random.c b/drivers/firmware/efi/libstub/random.c
new file mode 100644
index 000000000..f85d2c066
--- /dev/null
+++ b/drivers/firmware/efi/libstub/random.c
@@ -0,0 +1,143 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2016 Linaro Ltd;  <ard.biesheuvel@linaro.org>
+ */
+
+#include <linux/efi.h>
+#include <asm/efi.h>
+
+#include "efistub.h"
+
+typedef union efi_rng_protocol efi_rng_protocol_t;
+
+union efi_rng_protocol {
+	struct {
+		efi_status_t (__efiapi *get_info)(efi_rng_protocol_t *,
+						  unsigned long *,
+						  efi_guid_t *);
+		efi_status_t (__efiapi *get_rng)(efi_rng_protocol_t *,
+						 efi_guid_t *, unsigned long,
+						 u8 *out);
+	};
+	struct {
+		u32 get_info;
+		u32 get_rng;
+	} mixed_mode;
+};
+
+/**
+ * efi_get_random_bytes() - fill a buffer with random bytes
+ * @size:	size of the buffer
+ * @out:	caller allocated buffer to receive the random bytes
+ *
+ * The call will fail if either the firmware does not implement the
+ * EFI_RNG_PROTOCOL or there are not enough random bytes available to fill
+ * the buffer.
+ *
+ * Return:	status code
+ */
+efi_status_t efi_get_random_bytes(unsigned long size, u8 *out)
+{
+	efi_guid_t rng_proto = EFI_RNG_PROTOCOL_GUID;
+	efi_status_t status;
+	efi_rng_protocol_t *rng = NULL;
+
+	status = efi_bs_call(locate_protocol, &rng_proto, NULL, (void **)&rng);
+	if (status != EFI_SUCCESS)
+		return status;
+
+	return efi_call_proto(rng, get_rng, NULL, size, out);
+}
+
+/**
+ * efi_random_get_seed() - provide random seed as configuration table
+ *
+ * The EFI_RNG_PROTOCOL is used to read random bytes. These random bytes are
+ * saved as a configuration table which can be used as entropy by the kernel
+ * for the initialization of its pseudo random number generator.
+ *
+ * If the EFI_RNG_PROTOCOL is not available or there are not enough random bytes
+ * available, the configuration table will not be installed and an error code
+ * will be returned.
+ *
+ * Return:	status code
+ */
+efi_status_t efi_random_get_seed(void)
+{
+	efi_guid_t rng_proto = EFI_RNG_PROTOCOL_GUID;
+	efi_guid_t rng_algo_raw = EFI_RNG_ALGORITHM_RAW;
+	efi_guid_t rng_table_guid = LINUX_EFI_RANDOM_SEED_TABLE_GUID;
+	struct linux_efi_random_seed *prev_seed, *seed = NULL;
+	int prev_seed_size = 0, seed_size = EFI_RANDOM_SEED_SIZE;
+	efi_rng_protocol_t *rng = NULL;
+	efi_status_t status;
+
+	status = efi_bs_call(locate_protocol, &rng_proto, NULL, (void **)&rng);
+	if (status != EFI_SUCCESS)
+		return status;
+
+	/*
+	 * Check whether a seed was provided by a prior boot stage. In that
+	 * case, instead of overwriting it, let's create a new buffer that can
+	 * hold both, and concatenate the existing and the new seeds.
+	 * Note that we should read the seed size with caution, in case the
+	 * table got corrupted in memory somehow.
+	 */
+	prev_seed = get_efi_config_table(LINUX_EFI_RANDOM_SEED_TABLE_GUID);
+	if (prev_seed && prev_seed->size <= 512U) {
+		prev_seed_size = prev_seed->size;
+		seed_size += prev_seed_size;
+	}
+
+	/*
+	 * Use EFI_ACPI_RECLAIM_MEMORY here so that it is guaranteed that the
+	 * allocation will survive a kexec reboot (although we refresh the seed
+	 * beforehand)
+	 */
+	status = efi_bs_call(allocate_pool, EFI_ACPI_RECLAIM_MEMORY,
+			     struct_size(seed, bits, seed_size),
+			     (void **)&seed);
+	if (status != EFI_SUCCESS) {
+		efi_warn("Failed to allocate memory for RNG seed.\n");
+		goto err_warn;
+	}
+
+	status = efi_call_proto(rng, get_rng, &rng_algo_raw,
+				EFI_RANDOM_SEED_SIZE, seed->bits);
+
+	if (status == EFI_UNSUPPORTED)
+		/*
+		 * Use whatever algorithm we have available if the raw algorithm
+		 * is not implemented.
+		 */
+		status = efi_call_proto(rng, get_rng, NULL,
+					EFI_RANDOM_SEED_SIZE, seed->bits);
+
+	if (status != EFI_SUCCESS)
+		goto err_freepool;
+
+	seed->size = seed_size;
+	if (prev_seed_size)
+		memcpy(seed->bits + EFI_RANDOM_SEED_SIZE, prev_seed->bits,
+		       prev_seed_size);
+
+	status = efi_bs_call(install_configuration_table, &rng_table_guid, seed);
+	if (status != EFI_SUCCESS)
+		goto err_freepool;
+
+	if (prev_seed_size) {
+		/* wipe and free the old seed if we managed to install the new one */
+		memzero_explicit(prev_seed->bits, prev_seed_size);
+		efi_bs_call(free_pool, prev_seed);
+	}
+	return EFI_SUCCESS;
+
+err_freepool:
+	memzero_explicit(seed, struct_size(seed, bits, seed_size));
+	efi_bs_call(free_pool, seed);
+	efi_warn("Failed to obtain seed from EFI_RNG_PROTOCOL\n");
+err_warn:
+	if (prev_seed)
+		efi_warn("Retaining bootloader-supplied seed only");
+	return status;
+}
diff --git a/drivers/firmware/efi/libstub/randomalloc.c b/drivers/firmware/efi/libstub/randomalloc.c
new file mode 100644
index 000000000..9fb586989
--- /dev/null
+++ b/drivers/firmware/efi/libstub/randomalloc.c
@@ -0,0 +1,130 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2016 Linaro Ltd;  <ard.biesheuvel@linaro.org>
+ */
+
+#include <linux/efi.h>
+#include <linux/log2.h>
+#include <asm/efi.h>
+
+#include "efistub.h"
+
+/*
+ * Return the number of slots covered by this entry, i.e., the number of
+ * addresses it covers that are suitably aligned and supply enough room
+ * for the allocation.
+ */
+static unsigned long get_entry_num_slots(efi_memory_desc_t *md,
+					 unsigned long size,
+					 unsigned long align_shift)
+{
+	unsigned long align = 1UL << align_shift;
+	u64 first_slot, last_slot, region_end;
+
+	if (md->type != EFI_CONVENTIONAL_MEMORY)
+		return 0;
+
+	if (efi_soft_reserve_enabled() &&
+	    (md->attribute & EFI_MEMORY_SP))
+		return 0;
+
+	region_end = min(md->phys_addr + md->num_pages * EFI_PAGE_SIZE - 1,
+			 (u64)ULONG_MAX);
+	if (region_end < size)
+		return 0;
+
+	first_slot = round_up(md->phys_addr, align);
+	last_slot = round_down(region_end - size + 1, align);
+
+	if (first_slot > last_slot)
+		return 0;
+
+	return ((unsigned long)(last_slot - first_slot) >> align_shift) + 1;
+}
+
+/*
+ * The UEFI memory descriptors have a virtual address field that is only used
+ * when installing the virtual mapping using SetVirtualAddressMap(). Since it
+ * is unused here, we can reuse it to keep track of each descriptor's slot
+ * count.
+ */
+#define MD_NUM_SLOTS(md)	((md)->virt_addr)
+
+efi_status_t efi_random_alloc(unsigned long size,
+			      unsigned long align,
+			      unsigned long *addr,
+			      unsigned long random_seed)
+{
+	unsigned long total_slots = 0, target_slot;
+	unsigned long total_mirrored_slots = 0;
+	struct efi_boot_memmap *map;
+	efi_status_t status;
+	int map_offset;
+
+	status = efi_get_memory_map(&map, false);
+	if (status != EFI_SUCCESS)
+		return status;
+
+	if (align < EFI_ALLOC_ALIGN)
+		align = EFI_ALLOC_ALIGN;
+
+	size = round_up(size, EFI_ALLOC_ALIGN);
+
+	/* count the suitable slots in each memory map entry */
+	for (map_offset = 0; map_offset < map->map_size; map_offset += map->desc_size) {
+		efi_memory_desc_t *md = (void *)map->map + map_offset;
+		unsigned long slots;
+
+		slots = get_entry_num_slots(md, size, ilog2(align));
+		MD_NUM_SLOTS(md) = slots;
+		total_slots += slots;
+		if (md->attribute & EFI_MEMORY_MORE_RELIABLE)
+			total_mirrored_slots += slots;
+	}
+
+	/* consider only mirrored slots for randomization if any exist */
+	if (total_mirrored_slots > 0)
+		total_slots = total_mirrored_slots;
+
+	/* find a random number between 0 and total_slots */
+	target_slot = (total_slots * (u64)(random_seed & U32_MAX)) >> 32;
+
+	/*
+	 * target_slot is now a value in the range [0, total_slots), and so
+	 * it corresponds with exactly one of the suitable slots we recorded
+	 * when iterating over the memory map the first time around.
+	 *
+	 * So iterate over the memory map again, subtracting the number of
+	 * slots of each entry at each iteration, until we have found the entry
+	 * that covers our chosen slot. Use the residual value of target_slot
+	 * to calculate the randomly chosen address, and allocate it directly
+	 * using EFI_ALLOCATE_ADDRESS.
+	 */
+	for (map_offset = 0; map_offset < map->map_size; map_offset += map->desc_size) {
+		efi_memory_desc_t *md = (void *)map->map + map_offset;
+		efi_physical_addr_t target;
+		unsigned long pages;
+
+		if (total_mirrored_slots > 0 &&
+		    !(md->attribute & EFI_MEMORY_MORE_RELIABLE))
+			continue;
+
+		if (target_slot >= MD_NUM_SLOTS(md)) {
+			target_slot -= MD_NUM_SLOTS(md);
+			continue;
+		}
+
+		target = round_up(md->phys_addr, align) + target_slot * align;
+		pages = size / EFI_PAGE_SIZE;
+
+		status = efi_bs_call(allocate_pages, EFI_ALLOCATE_ADDRESS,
+				     EFI_LOADER_DATA, pages, &target);
+		if (status == EFI_SUCCESS)
+			*addr = target;
+		break;
+	}
+
+	efi_bs_call(free_pool, map);
+
+	return status;
+}
diff --git a/drivers/firmware/efi/libstub/relocate.c b/drivers/firmware/efi/libstub/relocate.c
new file mode 100644
index 000000000..bf6fbd5d2
--- /dev/null
+++ b/drivers/firmware/efi/libstub/relocate.c
@@ -0,0 +1,165 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/efi.h>
+#include <asm/efi.h>
+
+#include "efistub.h"
+
+/**
+ * efi_low_alloc_above() - allocate pages at or above given address
+ * @size:	size of the memory area to allocate
+ * @align:	minimum alignment of the allocated memory area. It should
+ *		a power of two.
+ * @addr:	on exit the address of the allocated memory
+ * @min:	minimum address to used for the memory allocation
+ *
+ * Allocate at the lowest possible address that is not below @min as
+ * EFI_LOADER_DATA. The allocated pages are aligned according to @align but at
+ * least EFI_ALLOC_ALIGN. The first allocated page will not below the address
+ * given by @min.
+ *
+ * Return:	status code
+ */
+efi_status_t efi_low_alloc_above(unsigned long size, unsigned long align,
+				 unsigned long *addr, unsigned long min)
+{
+	struct efi_boot_memmap *map;
+	efi_status_t status;
+	unsigned long nr_pages;
+	int i;
+
+	status = efi_get_memory_map(&map, false);
+	if (status != EFI_SUCCESS)
+		goto fail;
+
+	/*
+	 * Enforce minimum alignment that EFI or Linux requires when
+	 * requesting a specific address.  We are doing page-based (or
+	 * larger) allocations, and both the address and size must meet
+	 * alignment constraints.
+	 */
+	if (align < EFI_ALLOC_ALIGN)
+		align = EFI_ALLOC_ALIGN;
+
+	size = round_up(size, EFI_ALLOC_ALIGN);
+	nr_pages = size / EFI_PAGE_SIZE;
+	for (i = 0; i < map->map_size / map->desc_size; i++) {
+		efi_memory_desc_t *desc;
+		unsigned long m = (unsigned long)map->map;
+		u64 start, end;
+
+		desc = efi_early_memdesc_ptr(m, map->desc_size, i);
+
+		if (desc->type != EFI_CONVENTIONAL_MEMORY)
+			continue;
+
+		if (efi_soft_reserve_enabled() &&
+		    (desc->attribute & EFI_MEMORY_SP))
+			continue;
+
+		if (desc->num_pages < nr_pages)
+			continue;
+
+		start = desc->phys_addr;
+		end = start + desc->num_pages * EFI_PAGE_SIZE;
+
+		if (start < min)
+			start = min;
+
+		start = round_up(start, align);
+		if ((start + size) > end)
+			continue;
+
+		status = efi_bs_call(allocate_pages, EFI_ALLOCATE_ADDRESS,
+				     EFI_LOADER_DATA, nr_pages, &start);
+		if (status == EFI_SUCCESS) {
+			*addr = start;
+			break;
+		}
+	}
+
+	if (i == map->map_size / map->desc_size)
+		status = EFI_NOT_FOUND;
+
+	efi_bs_call(free_pool, map);
+fail:
+	return status;
+}
+
+/**
+ * efi_relocate_kernel() - copy memory area
+ * @image_addr:		pointer to address of memory area to copy
+ * @image_size:		size of memory area to copy
+ * @alloc_size:		minimum size of memory to allocate, must be greater or
+ *			equal to image_size
+ * @preferred_addr:	preferred target address
+ * @alignment:		minimum alignment of the allocated memory area. It
+ *			should be a power of two.
+ * @min_addr:		minimum target address
+ *
+ * Copy a memory area to a newly allocated memory area aligned according
+ * to @alignment but at least EFI_ALLOC_ALIGN. If the preferred address
+ * is not available, the allocated address will not be below @min_addr.
+ * On exit, @image_addr is updated to the target copy address that was used.
+ *
+ * This function is used to copy the Linux kernel verbatim. It does not apply
+ * any relocation changes.
+ *
+ * Return:		status code
+ */
+efi_status_t efi_relocate_kernel(unsigned long *image_addr,
+				 unsigned long image_size,
+				 unsigned long alloc_size,
+				 unsigned long preferred_addr,
+				 unsigned long alignment,
+				 unsigned long min_addr)
+{
+	unsigned long cur_image_addr;
+	unsigned long new_addr = 0;
+	efi_status_t status;
+	unsigned long nr_pages;
+	efi_physical_addr_t efi_addr = preferred_addr;
+
+	if (!image_addr || !image_size || !alloc_size)
+		return EFI_INVALID_PARAMETER;
+	if (alloc_size < image_size)
+		return EFI_INVALID_PARAMETER;
+
+	cur_image_addr = *image_addr;
+
+	/*
+	 * The EFI firmware loader could have placed the kernel image
+	 * anywhere in memory, but the kernel has restrictions on the
+	 * max physical address it can run at.  Some architectures
+	 * also have a preferred address, so first try to relocate
+	 * to the preferred address.  If that fails, allocate as low
+	 * as possible while respecting the required alignment.
+	 */
+	nr_pages = round_up(alloc_size, EFI_ALLOC_ALIGN) / EFI_PAGE_SIZE;
+	status = efi_bs_call(allocate_pages, EFI_ALLOCATE_ADDRESS,
+			     EFI_LOADER_DATA, nr_pages, &efi_addr);
+	new_addr = efi_addr;
+	/*
+	 * If preferred address allocation failed allocate as low as
+	 * possible.
+	 */
+	if (status != EFI_SUCCESS) {
+		status = efi_low_alloc_above(alloc_size, alignment, &new_addr,
+					     min_addr);
+	}
+	if (status != EFI_SUCCESS) {
+		efi_err("Failed to allocate usable memory for kernel.\n");
+		return status;
+	}
+
+	/*
+	 * We know source/dest won't overlap since both memory ranges
+	 * have been allocated by UEFI, so we can safely use memcpy.
+	 */
+	memcpy((void *)new_addr, (void *)cur_image_addr, image_size);
+
+	/* Return the new address of the relocated image. */
+	*image_addr = new_addr;
+
+	return status;
+}
diff --git a/drivers/firmware/efi/libstub/riscv-stub.c b/drivers/firmware/efi/libstub/riscv-stub.c
new file mode 100644
index 000000000..b450ebf95
--- /dev/null
+++ b/drivers/firmware/efi/libstub/riscv-stub.c
@@ -0,0 +1,137 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2020 Western Digital Corporation or its affiliates.
+ */
+
+#include <linux/efi.h>
+#include <linux/libfdt.h>
+
+#include <asm/efi.h>
+#include <asm/sections.h>
+#include <asm/unaligned.h>
+
+#include "efistub.h"
+
+/*
+ * RISC-V requires the kernel image to placed 2 MB aligned base for 64 bit and
+ * 4MB for 32 bit.
+ */
+#ifdef CONFIG_64BIT
+#define MIN_KIMG_ALIGN		SZ_2M
+#else
+#define MIN_KIMG_ALIGN		SZ_4M
+#endif
+
+typedef void __noreturn (*jump_kernel_func)(unsigned long, unsigned long);
+
+static unsigned long hartid;
+
+static int get_boot_hartid_from_fdt(void)
+{
+	const void *fdt;
+	int chosen_node, len;
+	const void *prop;
+
+	fdt = get_efi_config_table(DEVICE_TREE_GUID);
+	if (!fdt)
+		return -EINVAL;
+
+	chosen_node = fdt_path_offset(fdt, "/chosen");
+	if (chosen_node < 0)
+		return -EINVAL;
+
+	prop = fdt_getprop((void *)fdt, chosen_node, "boot-hartid", &len);
+	if (!prop)
+		return -EINVAL;
+
+	if (len == sizeof(u32))
+		hartid = (unsigned long) fdt32_to_cpu(*(fdt32_t *)prop);
+	else if (len == sizeof(u64))
+		hartid = (unsigned long) fdt64_to_cpu(__get_unaligned_t(fdt64_t, prop));
+	else
+		return -EINVAL;
+
+	return 0;
+}
+
+static efi_status_t get_boot_hartid_from_efi(void)
+{
+	efi_guid_t boot_protocol_guid = RISCV_EFI_BOOT_PROTOCOL_GUID;
+	struct riscv_efi_boot_protocol *boot_protocol;
+	efi_status_t status;
+
+	status = efi_bs_call(locate_protocol, &boot_protocol_guid, NULL,
+			     (void **)&boot_protocol);
+	if (status != EFI_SUCCESS)
+		return status;
+	return efi_call_proto(boot_protocol, get_boot_hartid, &hartid);
+}
+
+efi_status_t check_platform_features(void)
+{
+	efi_status_t status;
+	int ret;
+
+	status = get_boot_hartid_from_efi();
+	if (status != EFI_SUCCESS) {
+		ret = get_boot_hartid_from_fdt();
+		if (ret) {
+			efi_err("Failed to get boot hartid!\n");
+			return EFI_UNSUPPORTED;
+		}
+	}
+	return EFI_SUCCESS;
+}
+
+void __noreturn efi_enter_kernel(unsigned long entrypoint, unsigned long fdt,
+				 unsigned long fdt_size)
+{
+	unsigned long stext_offset = _start_kernel - _start;
+	unsigned long kernel_entry = entrypoint + stext_offset;
+	jump_kernel_func jump_kernel = (jump_kernel_func)kernel_entry;
+
+	/*
+	 * Jump to real kernel here with following constraints.
+	 * 1. MMU should be disabled.
+	 * 2. a0 should contain hartid
+	 * 3. a1 should DT address
+	 */
+	csr_write(CSR_SATP, 0);
+	jump_kernel(hartid, fdt);
+}
+
+efi_status_t handle_kernel_image(unsigned long *image_addr,
+				 unsigned long *image_size,
+				 unsigned long *reserve_addr,
+				 unsigned long *reserve_size,
+				 efi_loaded_image_t *image,
+				 efi_handle_t image_handle)
+{
+	unsigned long kernel_size = 0;
+	unsigned long preferred_addr;
+	efi_status_t status;
+
+	kernel_size = _edata - _start;
+	*image_addr = (unsigned long)_start;
+	*image_size = kernel_size + (_end - _edata);
+
+	/*
+	 * RISC-V kernel maps PAGE_OFFSET virtual address to the same physical
+	 * address where kernel is booted. That's why kernel should boot from
+	 * as low as possible to avoid wastage of memory. Currently, dram_base
+	 * is occupied by the firmware. So the preferred address for kernel to
+	 * boot is next aligned address. If preferred address is not available,
+	 * relocate_kernel will fall back to efi_low_alloc_above to allocate
+	 * lowest possible memory region as long as the address and size meets
+	 * the alignment constraints.
+	 */
+	preferred_addr = MIN_KIMG_ALIGN;
+	status = efi_relocate_kernel(image_addr, kernel_size, *image_size,
+				     preferred_addr, MIN_KIMG_ALIGN, 0x0);
+
+	if (status != EFI_SUCCESS) {
+		efi_err("Failed to relocate kernel\n");
+		*image_size = 0;
+	}
+	return status;
+}
diff --git a/drivers/firmware/efi/libstub/secureboot.c b/drivers/firmware/efi/libstub/secureboot.c
new file mode 100644
index 000000000..516f4f006
--- /dev/null
+++ b/drivers/firmware/efi/libstub/secureboot.c
@@ -0,0 +1,62 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Secure boot handling.
+ *
+ * Copyright (C) 2013,2014 Linaro Limited
+ *     Roy Franz <roy.franz@linaro.org
+ * Copyright (C) 2013 Red Hat, Inc.
+ *     Mark Salter <msalter@redhat.com>
+ */
+#include <linux/efi.h>
+#include <asm/efi.h>
+
+#include "efistub.h"
+
+/* SHIM variables */
+static const efi_guid_t shim_guid = EFI_SHIM_LOCK_GUID;
+static const efi_char16_t shim_MokSBState_name[] = L"MokSBStateRT";
+
+static efi_status_t get_var(efi_char16_t *name, efi_guid_t *vendor, u32 *attr,
+			    unsigned long *data_size, void *data)
+{
+	return get_efi_var(name, vendor, attr, data_size, data);
+}
+
+/*
+ * Determine whether we're in secure boot mode.
+ */
+enum efi_secureboot_mode efi_get_secureboot(void)
+{
+	u32 attr;
+	unsigned long size;
+	enum efi_secureboot_mode mode;
+	efi_status_t status;
+	u8 moksbstate;
+
+	mode = efi_get_secureboot_mode(get_var);
+	if (mode == efi_secureboot_mode_unknown) {
+		efi_err("Could not determine UEFI Secure Boot status.\n");
+		return efi_secureboot_mode_unknown;
+	}
+	if (mode != efi_secureboot_mode_enabled)
+		return mode;
+
+	/*
+	 * See if a user has put the shim into insecure mode. If so, and if the
+	 * variable doesn't have the non-volatile attribute set, we might as
+	 * well honor that.
+	 */
+	size = sizeof(moksbstate);
+	status = get_efi_var(shim_MokSBState_name, &shim_guid,
+			     &attr, &size, &moksbstate);
+
+	/* If it fails, we don't care why. Default to secure */
+	if (status != EFI_SUCCESS)
+		goto secure_boot_enabled;
+	if (!(attr & EFI_VARIABLE_NON_VOLATILE) && moksbstate == 1)
+		return efi_secureboot_mode_disabled;
+
+secure_boot_enabled:
+	efi_info("UEFI Secure Boot is enabled.\n");
+	return efi_secureboot_mode_enabled;
+}
diff --git a/drivers/firmware/efi/libstub/skip_spaces.c b/drivers/firmware/efi/libstub/skip_spaces.c
new file mode 100644
index 000000000..159fb4e45
--- /dev/null
+++ b/drivers/firmware/efi/libstub/skip_spaces.c
@@ -0,0 +1,12 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/ctype.h>
+#include <linux/string.h>
+#include <linux/types.h>
+
+char *skip_spaces(const char *str)
+{
+	while (isspace(*str))
+		++str;
+	return (char *)str;
+}
diff --git a/drivers/firmware/efi/libstub/smbios.c b/drivers/firmware/efi/libstub/smbios.c
new file mode 100644
index 000000000..f9c159c28
--- /dev/null
+++ b/drivers/firmware/efi/libstub/smbios.c
@@ -0,0 +1,57 @@
+// SPDX-License-Identifier: GPL-2.0-only
+// Copyright 2022 Google LLC
+// Author: Ard Biesheuvel <ardb@google.com>
+
+#include <linux/efi.h>
+
+#include "efistub.h"
+
+typedef struct efi_smbios_protocol efi_smbios_protocol_t;
+
+struct efi_smbios_protocol {
+	efi_status_t (__efiapi *add)(efi_smbios_protocol_t *, efi_handle_t,
+				     u16 *, struct efi_smbios_record *);
+	efi_status_t (__efiapi *update_string)(efi_smbios_protocol_t *, u16 *,
+					       unsigned long *, u8 *);
+	efi_status_t (__efiapi *remove)(efi_smbios_protocol_t *, u16);
+	efi_status_t (__efiapi *get_next)(efi_smbios_protocol_t *, u16 *, u8 *,
+					  struct efi_smbios_record **,
+					  efi_handle_t *);
+
+	u8 major_version;
+	u8 minor_version;
+};
+
+const struct efi_smbios_record *efi_get_smbios_record(u8 type)
+{
+	struct efi_smbios_record *record;
+	efi_smbios_protocol_t *smbios;
+	efi_status_t status;
+	u16 handle = 0xfffe;
+
+	status = efi_bs_call(locate_protocol, &EFI_SMBIOS_PROTOCOL_GUID, NULL,
+			     (void **)&smbios) ?:
+		 efi_call_proto(smbios, get_next, &handle, &type, &record, NULL);
+	if (status != EFI_SUCCESS)
+		return NULL;
+	return record;
+}
+
+const u8 *__efi_get_smbios_string(const struct efi_smbios_record *record,
+				  u8 type, int offset, int recsize)
+{
+	const u8 *strtable;
+
+	if (!record)
+		return NULL;
+
+	strtable = (u8 *)record + record->length;
+	for (int i = 1; i < ((u8 *)record)[offset]; i++) {
+		int len = strlen(strtable);
+
+		if (!len)
+			return NULL;
+		strtable += len + 1;
+	}
+	return strtable;
+}
diff --git a/drivers/firmware/efi/libstub/string.c b/drivers/firmware/efi/libstub/string.c
new file mode 100644
index 000000000..5d13e4386
--- /dev/null
+++ b/drivers/firmware/efi/libstub/string.c
@@ -0,0 +1,115 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Taken from:
+ *  linux/lib/string.c
+ *
+ *  Copyright (C) 1991, 1992  Linus Torvalds
+ */
+
+#include <linux/ctype.h>
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/string.h>
+
+#ifndef __HAVE_ARCH_STRSTR
+/**
+ * strstr - Find the first substring in a %NUL terminated string
+ * @s1: The string to be searched
+ * @s2: The string to search for
+ */
+char *strstr(const char *s1, const char *s2)
+{
+	size_t l1, l2;
+
+	l2 = strlen(s2);
+	if (!l2)
+		return (char *)s1;
+	l1 = strlen(s1);
+	while (l1 >= l2) {
+		l1--;
+		if (!memcmp(s1, s2, l2))
+			return (char *)s1;
+		s1++;
+	}
+	return NULL;
+}
+#endif
+
+#ifndef __HAVE_ARCH_STRNCMP
+/**
+ * strncmp - Compare two length-limited strings
+ * @cs: One string
+ * @ct: Another string
+ * @count: The maximum number of bytes to compare
+ */
+int strncmp(const char *cs, const char *ct, size_t count)
+{
+	unsigned char c1, c2;
+
+	while (count) {
+		c1 = *cs++;
+		c2 = *ct++;
+		if (c1 != c2)
+			return c1 < c2 ? -1 : 1;
+		if (!c1)
+			break;
+		count--;
+	}
+	return 0;
+}
+#endif
+
+/* Works only for digits and letters, but small and fast */
+#define TOLOWER(x) ((x) | 0x20)
+
+static unsigned int simple_guess_base(const char *cp)
+{
+	if (cp[0] == '0') {
+		if (TOLOWER(cp[1]) == 'x' && isxdigit(cp[2]))
+			return 16;
+		else
+			return 8;
+	} else {
+		return 10;
+	}
+}
+
+/**
+ * simple_strtoull - convert a string to an unsigned long long
+ * @cp: The start of the string
+ * @endp: A pointer to the end of the parsed string will be placed here
+ * @base: The number base to use
+ */
+
+unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base)
+{
+	unsigned long long result = 0;
+
+	if (!base)
+		base = simple_guess_base(cp);
+
+	if (base == 16 && cp[0] == '0' && TOLOWER(cp[1]) == 'x')
+		cp += 2;
+
+	while (isxdigit(*cp)) {
+		unsigned int value;
+
+		value = isdigit(*cp) ? *cp - '0' : TOLOWER(*cp) - 'a' + 10;
+		if (value >= base)
+			break;
+		result = result * base + value;
+		cp++;
+	}
+	if (endp)
+		*endp = (char *)cp;
+
+	return result;
+}
+
+long simple_strtol(const char *cp, char **endp, unsigned int base)
+{
+	if (*cp == '-')
+		return -simple_strtoull(cp + 1, endp, base);
+
+	return simple_strtoull(cp, endp, base);
+}
diff --git a/drivers/firmware/efi/libstub/systable.c b/drivers/firmware/efi/libstub/systable.c
new file mode 100644
index 000000000..91d016b02
--- /dev/null
+++ b/drivers/firmware/efi/libstub/systable.c
@@ -0,0 +1,8 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/efi.h>
+#include <asm/efi.h>
+
+#include "efistub.h"
+
+const efi_system_table_t *efi_system_table;
diff --git a/drivers/firmware/efi/libstub/tpm.c b/drivers/firmware/efi/libstub/tpm.c
new file mode 100644
index 000000000..7acbac16e
--- /dev/null
+++ b/drivers/firmware/efi/libstub/tpm.c
@@ -0,0 +1,167 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * TPM handling.
+ *
+ * Copyright (C) 2016 CoreOS, Inc
+ * Copyright (C) 2017 Google, Inc.
+ *     Matthew Garrett <mjg59@google.com>
+ *     Thiebaud Weksteen <tweek@google.com>
+ */
+#include <linux/efi.h>
+#include <linux/tpm_eventlog.h>
+#include <asm/efi.h>
+
+#include "efistub.h"
+
+#ifdef CONFIG_RESET_ATTACK_MITIGATION
+static const efi_char16_t efi_MemoryOverWriteRequest_name[] =
+	L"MemoryOverwriteRequestControl";
+
+#define MEMORY_ONLY_RESET_CONTROL_GUID \
+	EFI_GUID(0xe20939be, 0x32d4, 0x41be, 0xa1, 0x50, 0x89, 0x7f, 0x85, 0xd4, 0x98, 0x29)
+
+/*
+ * Enable reboot attack mitigation. This requests that the firmware clear the
+ * RAM on next reboot before proceeding with boot, ensuring that any secrets
+ * are cleared. If userland has ensured that all secrets have been removed
+ * from RAM before reboot it can simply reset this variable.
+ */
+void efi_enable_reset_attack_mitigation(void)
+{
+	u8 val = 1;
+	efi_guid_t var_guid = MEMORY_ONLY_RESET_CONTROL_GUID;
+	efi_status_t status;
+	unsigned long datasize = 0;
+
+	status = get_efi_var(efi_MemoryOverWriteRequest_name, &var_guid,
+			     NULL, &datasize, NULL);
+
+	if (status == EFI_NOT_FOUND)
+		return;
+
+	set_efi_var(efi_MemoryOverWriteRequest_name, &var_guid,
+		    EFI_VARIABLE_NON_VOLATILE |
+		    EFI_VARIABLE_BOOTSERVICE_ACCESS |
+		    EFI_VARIABLE_RUNTIME_ACCESS, sizeof(val), &val);
+}
+
+#endif
+
+void efi_retrieve_tpm2_eventlog(void)
+{
+	efi_guid_t tcg2_guid = EFI_TCG2_PROTOCOL_GUID;
+	efi_guid_t linux_eventlog_guid = LINUX_EFI_TPM_EVENT_LOG_GUID;
+	efi_status_t status;
+	efi_physical_addr_t log_location = 0, log_last_entry = 0;
+	struct linux_efi_tpm_eventlog *log_tbl = NULL;
+	struct efi_tcg2_final_events_table *final_events_table = NULL;
+	unsigned long first_entry_addr, last_entry_addr;
+	size_t log_size, last_entry_size;
+	efi_bool_t truncated;
+	int version = EFI_TCG2_EVENT_LOG_FORMAT_TCG_2;
+	efi_tcg2_protocol_t *tcg2_protocol = NULL;
+	int final_events_size = 0;
+
+	status = efi_bs_call(locate_protocol, &tcg2_guid, NULL,
+			     (void **)&tcg2_protocol);
+	if (status != EFI_SUCCESS)
+		return;
+
+	status = efi_call_proto(tcg2_protocol, get_event_log, version,
+				&log_location, &log_last_entry, &truncated);
+
+	if (status != EFI_SUCCESS || !log_location) {
+		version = EFI_TCG2_EVENT_LOG_FORMAT_TCG_1_2;
+		status = efi_call_proto(tcg2_protocol, get_event_log, version,
+					&log_location, &log_last_entry,
+					&truncated);
+		if (status != EFI_SUCCESS || !log_location)
+			return;
+
+	}
+
+	first_entry_addr = (unsigned long) log_location;
+
+	/*
+	 * We populate the EFI table even if the logs are empty.
+	 */
+	if (!log_last_entry) {
+		log_size = 0;
+	} else {
+		last_entry_addr = (unsigned long) log_last_entry;
+		/*
+		 * get_event_log only returns the address of the last entry.
+		 * We need to calculate its size to deduce the full size of
+		 * the logs.
+		 */
+		if (version == EFI_TCG2_EVENT_LOG_FORMAT_TCG_2) {
+			/*
+			 * The TCG2 log format has variable length entries,
+			 * and the information to decode the hash algorithms
+			 * back into a size is contained in the first entry -
+			 * pass a pointer to the final entry (to calculate its
+			 * size) and the first entry (so we know how long each
+			 * digest is)
+			 */
+			last_entry_size =
+				__calc_tpm2_event_size((void *)last_entry_addr,
+						    (void *)(long)log_location,
+						    false);
+		} else {
+			last_entry_size = sizeof(struct tcpa_event) +
+			   ((struct tcpa_event *) last_entry_addr)->event_size;
+		}
+		log_size = log_last_entry - log_location + last_entry_size;
+	}
+
+	/* Allocate space for the logs and copy them. */
+	status = efi_bs_call(allocate_pool, EFI_LOADER_DATA,
+			     sizeof(*log_tbl) + log_size, (void **)&log_tbl);
+
+	if (status != EFI_SUCCESS) {
+		efi_err("Unable to allocate memory for event log\n");
+		return;
+	}
+
+	/*
+	 * Figure out whether any events have already been logged to the
+	 * final events structure, and if so how much space they take up
+	 */
+	if (version == EFI_TCG2_EVENT_LOG_FORMAT_TCG_2)
+		final_events_table = get_efi_config_table(LINUX_EFI_TPM_FINAL_LOG_GUID);
+	if (final_events_table && final_events_table->nr_events) {
+		struct tcg_pcr_event2_head *header;
+		int offset;
+		void *data;
+		int event_size;
+		int i = final_events_table->nr_events;
+
+		data = (void *)final_events_table;
+		offset = sizeof(final_events_table->version) +
+			sizeof(final_events_table->nr_events);
+
+		while (i > 0) {
+			header = data + offset + final_events_size;
+			event_size = __calc_tpm2_event_size(header,
+						   (void *)(long)log_location,
+						   false);
+			final_events_size += event_size;
+			i--;
+		}
+	}
+
+	memset(log_tbl, 0, sizeof(*log_tbl) + log_size);
+	log_tbl->size = log_size;
+	log_tbl->final_events_preboot_size = final_events_size;
+	log_tbl->version = version;
+	memcpy(log_tbl->log, (void *) first_entry_addr, log_size);
+
+	status = efi_bs_call(install_configuration_table,
+			     &linux_eventlog_guid, log_tbl);
+	if (status != EFI_SUCCESS)
+		goto err_free;
+	return;
+
+err_free:
+	efi_bs_call(free_pool, log_tbl);
+}
diff --git a/drivers/firmware/efi/libstub/vsprintf.c b/drivers/firmware/efi/libstub/vsprintf.c
new file mode 100644
index 000000000..71c71c222
--- /dev/null
+++ b/drivers/firmware/efi/libstub/vsprintf.c
@@ -0,0 +1,564 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* -*- linux-c -*- ------------------------------------------------------- *
+ *
+ *   Copyright (C) 1991, 1992 Linus Torvalds
+ *   Copyright 2007 rPath, Inc. - All Rights Reserved
+ *
+ * ----------------------------------------------------------------------- */
+
+/*
+ * Oh, it's a waste of space, but oh-so-yummy for debugging.
+ */
+
+#include <linux/stdarg.h>
+
+#include <linux/compiler.h>
+#include <linux/ctype.h>
+#include <linux/kernel.h>
+#include <linux/limits.h>
+#include <linux/string.h>
+#include <linux/types.h>
+
+static
+int skip_atoi(const char **s)
+{
+	int i = 0;
+
+	while (isdigit(**s))
+		i = i * 10 + *((*s)++) - '0';
+	return i;
+}
+
+/*
+ * put_dec_full4 handles numbers in the range 0 <= r < 10000.
+ * The multiplier 0xccd is round(2^15/10), and the approximation
+ * r/10 == (r * 0xccd) >> 15 is exact for all r < 16389.
+ */
+static
+void put_dec_full4(char *end, unsigned int r)
+{
+	int i;
+
+	for (i = 0; i < 3; i++) {
+		unsigned int q = (r * 0xccd) >> 15;
+		*--end = '0' + (r - q * 10);
+		r = q;
+	}
+	*--end = '0' + r;
+}
+
+/* put_dec is copied from lib/vsprintf.c with small modifications */
+
+/*
+ * Call put_dec_full4 on x % 10000, return x / 10000.
+ * The approximation x/10000 == (x * 0x346DC5D7) >> 43
+ * holds for all x < 1,128,869,999.  The largest value this
+ * helper will ever be asked to convert is 1,125,520,955.
+ * (second call in the put_dec code, assuming n is all-ones).
+ */
+static
+unsigned int put_dec_helper4(char *end, unsigned int x)
+{
+	unsigned int q = (x * 0x346DC5D7ULL) >> 43;
+
+	put_dec_full4(end, x - q * 10000);
+	return q;
+}
+
+/* Based on code by Douglas W. Jones found at
+ * <http://www.cs.uiowa.edu/~jones/bcd/decimal.html#sixtyfour>
+ * (with permission from the author).
+ * Performs no 64-bit division and hence should be fast on 32-bit machines.
+ */
+static
+char *put_dec(char *end, unsigned long long n)
+{
+	unsigned int d3, d2, d1, q, h;
+	char *p = end;
+
+	d1  = ((unsigned int)n >> 16); /* implicit "& 0xffff" */
+	h   = (n >> 32);
+	d2  = (h      ) & 0xffff;
+	d3  = (h >> 16); /* implicit "& 0xffff" */
+
+	/* n = 2^48 d3 + 2^32 d2 + 2^16 d1 + d0
+	     = 281_4749_7671_0656 d3 + 42_9496_7296 d2 + 6_5536 d1 + d0 */
+	q = 656 * d3 + 7296 * d2 + 5536 * d1 + ((unsigned int)n & 0xffff);
+	q = put_dec_helper4(p, q);
+	p -= 4;
+
+	q += 7671 * d3 + 9496 * d2 + 6 * d1;
+	q = put_dec_helper4(p, q);
+	p -= 4;
+
+	q += 4749 * d3 + 42 * d2;
+	q = put_dec_helper4(p, q);
+	p -= 4;
+
+	q += 281 * d3;
+	q = put_dec_helper4(p, q);
+	p -= 4;
+
+	put_dec_full4(p, q);
+	p -= 4;
+
+	/* strip off the extra 0's we printed */
+	while (p < end && *p == '0')
+		++p;
+
+	return p;
+}
+
+static
+char *number(char *end, unsigned long long num, int base, char locase)
+{
+	/*
+	 * locase = 0 or 0x20. ORing digits or letters with 'locase'
+	 * produces same digits or (maybe lowercased) letters
+	 */
+
+	/* we are called with base 8, 10 or 16, only, thus don't need "G..."  */
+	static const char digits[16] = "0123456789ABCDEF"; /* "GHIJKLMNOPQRSTUVWXYZ"; */
+
+	switch (base) {
+	case 10:
+		if (num != 0)
+			end = put_dec(end, num);
+		break;
+	case 8:
+		for (; num != 0; num >>= 3)
+			*--end = '0' + (num & 07);
+		break;
+	case 16:
+		for (; num != 0; num >>= 4)
+			*--end = digits[num & 0xf] | locase;
+		break;
+	default:
+		unreachable();
+	}
+
+	return end;
+}
+
+#define ZEROPAD	1		/* pad with zero */
+#define SIGN	2		/* unsigned/signed long */
+#define PLUS	4		/* show plus */
+#define SPACE	8		/* space if plus */
+#define LEFT	16		/* left justified */
+#define SMALL	32		/* Must be 32 == 0x20 */
+#define SPECIAL	64		/* 0x */
+#define WIDE	128		/* UTF-16 string */
+
+static
+int get_flags(const char **fmt)
+{
+	int flags = 0;
+
+	do {
+		switch (**fmt) {
+		case '-':
+			flags |= LEFT;
+			break;
+		case '+':
+			flags |= PLUS;
+			break;
+		case ' ':
+			flags |= SPACE;
+			break;
+		case '#':
+			flags |= SPECIAL;
+			break;
+		case '0':
+			flags |= ZEROPAD;
+			break;
+		default:
+			return flags;
+		}
+		++(*fmt);
+	} while (1);
+}
+
+static
+int get_int(const char **fmt, va_list *ap)
+{
+	if (isdigit(**fmt))
+		return skip_atoi(fmt);
+	if (**fmt == '*') {
+		++(*fmt);
+		/* it's the next argument */
+		return va_arg(*ap, int);
+	}
+	return 0;
+}
+
+static
+unsigned long long get_number(int sign, int qualifier, va_list *ap)
+{
+	if (sign) {
+		switch (qualifier) {
+		case 'L':
+			return va_arg(*ap, long long);
+		case 'l':
+			return va_arg(*ap, long);
+		case 'h':
+			return (short)va_arg(*ap, int);
+		case 'H':
+			return (signed char)va_arg(*ap, int);
+		default:
+			return va_arg(*ap, int);
+		};
+	} else {
+		switch (qualifier) {
+		case 'L':
+			return va_arg(*ap, unsigned long long);
+		case 'l':
+			return va_arg(*ap, unsigned long);
+		case 'h':
+			return (unsigned short)va_arg(*ap, int);
+		case 'H':
+			return (unsigned char)va_arg(*ap, int);
+		default:
+			return va_arg(*ap, unsigned int);
+		}
+	}
+}
+
+static
+char get_sign(long long *num, int flags)
+{
+	if (!(flags & SIGN))
+		return 0;
+	if (*num < 0) {
+		*num = -(*num);
+		return '-';
+	}
+	if (flags & PLUS)
+		return '+';
+	if (flags & SPACE)
+		return ' ';
+	return 0;
+}
+
+static
+size_t utf16s_utf8nlen(const u16 *s16, size_t maxlen)
+{
+	size_t len, clen;
+
+	for (len = 0; len < maxlen && *s16; len += clen) {
+		u16 c0 = *s16++;
+
+		/* First, get the length for a BMP character */
+		clen = 1 + (c0 >= 0x80) + (c0 >= 0x800);
+		if (len + clen > maxlen)
+			break;
+		/*
+		 * If this is a high surrogate, and we're already at maxlen, we
+		 * can't include the character if it's a valid surrogate pair.
+		 * Avoid accessing one extra word just to check if it's valid
+		 * or not.
+		 */
+		if ((c0 & 0xfc00) == 0xd800) {
+			if (len + clen == maxlen)
+				break;
+			if ((*s16 & 0xfc00) == 0xdc00) {
+				++s16;
+				++clen;
+			}
+		}
+	}
+
+	return len;
+}
+
+static
+u32 utf16_to_utf32(const u16 **s16)
+{
+	u16 c0, c1;
+
+	c0 = *(*s16)++;
+	/* not a surrogate */
+	if ((c0 & 0xf800) != 0xd800)
+		return c0;
+	/* invalid: low surrogate instead of high */
+	if (c0 & 0x0400)
+		return 0xfffd;
+	c1 = **s16;
+	/* invalid: missing low surrogate */
+	if ((c1 & 0xfc00) != 0xdc00)
+		return 0xfffd;
+	/* valid surrogate pair */
+	++(*s16);
+	return (0x10000 - (0xd800 << 10) - 0xdc00) + (c0 << 10) + c1;
+}
+
+#define PUTC(c) \
+do {				\
+	if (pos < size)		\
+		buf[pos] = (c);	\
+	++pos;			\
+} while (0);
+
+int vsnprintf(char *buf, size_t size, const char *fmt, va_list ap)
+{
+	/* The maximum space required is to print a 64-bit number in octal */
+	char tmp[(sizeof(unsigned long long) * 8 + 2) / 3];
+	char *tmp_end = &tmp[ARRAY_SIZE(tmp)];
+	long long num;
+	int base;
+	const char *s;
+	size_t len, pos;
+	char sign;
+
+	int flags;		/* flags to number() */
+
+	int field_width;	/* width of output field */
+	int precision;		/* min. # of digits for integers; max
+				   number of chars for from string */
+	int qualifier;		/* 'h', 'hh', 'l' or 'll' for integer fields */
+
+	va_list args;
+
+	/*
+	 * We want to pass our input va_list to helper functions by reference,
+	 * but there's an annoying edge case. If va_list was originally passed
+	 * to us by value, we could just pass &ap down to the helpers. This is
+	 * the case on, for example, X86_32.
+	 * However, on X86_64 (and possibly others), va_list is actually a
+	 * size-1 array containing a structure. Our function parameter ap has
+	 * decayed from T[1] to T*, and &ap has type T** rather than T(*)[1],
+	 * which is what will be expected by a function taking a va_list *
+	 * parameter.
+	 * One standard way to solve this mess is by creating a copy in a local
+	 * variable of type va_list and then passing a pointer to that local
+	 * copy instead, which is what we do here.
+	 */
+	va_copy(args, ap);
+
+	for (pos = 0; *fmt; ++fmt) {
+		if (*fmt != '%' || *++fmt == '%') {
+			PUTC(*fmt);
+			continue;
+		}
+
+		/* process flags */
+		flags = get_flags(&fmt);
+
+		/* get field width */
+		field_width = get_int(&fmt, &args);
+		if (field_width < 0) {
+			field_width = -field_width;
+			flags |= LEFT;
+		}
+
+		if (flags & LEFT)
+			flags &= ~ZEROPAD;
+
+		/* get the precision */
+		precision = -1;
+		if (*fmt == '.') {
+			++fmt;
+			precision = get_int(&fmt, &args);
+			if (precision >= 0)
+				flags &= ~ZEROPAD;
+		}
+
+		/* get the conversion qualifier */
+		qualifier = -1;
+		if (*fmt == 'h' || *fmt == 'l') {
+			qualifier = *fmt;
+			++fmt;
+			if (qualifier == *fmt) {
+				qualifier -= 'a'-'A';
+				++fmt;
+			}
+		}
+
+		sign = 0;
+
+		switch (*fmt) {
+		case 'c':
+			flags &= LEFT;
+			s = tmp;
+			if (qualifier == 'l') {
+				((u16 *)tmp)[0] = (u16)va_arg(args, unsigned int);
+				((u16 *)tmp)[1] = L'\0';
+				precision = INT_MAX;
+				goto wstring;
+			} else {
+				tmp[0] = (unsigned char)va_arg(args, int);
+				precision = len = 1;
+			}
+			goto output;
+
+		case 's':
+			flags &= LEFT;
+			if (precision < 0)
+				precision = INT_MAX;
+			s = va_arg(args, void *);
+			if (!s)
+				s = precision < 6 ? "" : "(null)";
+			else if (qualifier == 'l') {
+		wstring:
+				flags |= WIDE;
+				precision = len = utf16s_utf8nlen((const u16 *)s, precision);
+				goto output;
+			}
+			precision = len = strnlen(s, precision);
+			goto output;
+
+			/* integer number formats - set up the flags and "break" */
+		case 'o':
+			base = 8;
+			break;
+
+		case 'p':
+			if (precision < 0)
+				precision = 2 * sizeof(void *);
+			fallthrough;
+		case 'x':
+			flags |= SMALL;
+			fallthrough;
+		case 'X':
+			base = 16;
+			break;
+
+		case 'd':
+		case 'i':
+			flags |= SIGN;
+			fallthrough;
+		case 'u':
+			flags &= ~SPECIAL;
+			base = 10;
+			break;
+
+		default:
+			/*
+			 * Bail out if the conversion specifier is invalid.
+			 * There's probably a typo in the format string and the
+			 * remaining specifiers are unlikely to match up with
+			 * the arguments.
+			 */
+			goto fail;
+		}
+		if (*fmt == 'p') {
+			num = (unsigned long)va_arg(args, void *);
+		} else {
+			num = get_number(flags & SIGN, qualifier, &args);
+		}
+
+		sign = get_sign(&num, flags);
+		if (sign)
+			--field_width;
+
+		s = number(tmp_end, num, base, flags & SMALL);
+		len = tmp_end - s;
+		/* default precision is 1 */
+		if (precision < 0)
+			precision = 1;
+		/* precision is minimum number of digits to print */
+		if (precision < len)
+			precision = len;
+		if (flags & SPECIAL) {
+			/*
+			 * For octal, a leading 0 is printed only if necessary,
+			 * i.e. if it's not already there because of the
+			 * precision.
+			 */
+			if (base == 8 && precision == len)
+				++precision;
+			/*
+			 * For hexadecimal, the leading 0x is skipped if the
+			 * output is empty, i.e. both the number and the
+			 * precision are 0.
+			 */
+			if (base == 16 && precision > 0)
+				field_width -= 2;
+			else
+				flags &= ~SPECIAL;
+		}
+		/*
+		 * For zero padding, increase the precision to fill the field
+		 * width.
+		 */
+		if ((flags & ZEROPAD) && field_width > precision)
+			precision = field_width;
+
+output:
+		/* Calculate the padding necessary */
+		field_width -= precision;
+		/* Leading padding with ' ' */
+		if (!(flags & LEFT))
+			while (field_width-- > 0)
+				PUTC(' ');
+		/* sign */
+		if (sign)
+			PUTC(sign);
+		/* 0x/0X for hexadecimal */
+		if (flags & SPECIAL) {
+			PUTC('0');
+			PUTC( 'X' | (flags & SMALL));
+		}
+		/* Zero padding and excess precision */
+		while (precision-- > len)
+			PUTC('0');
+		/* Actual output */
+		if (flags & WIDE) {
+			const u16 *ws = (const u16 *)s;
+
+			while (len-- > 0) {
+				u32 c32 = utf16_to_utf32(&ws);
+				u8 *s8;
+				size_t clen;
+
+				if (c32 < 0x80) {
+					PUTC(c32);
+					continue;
+				}
+
+				/* Number of trailing octets */
+				clen = 1 + (c32 >= 0x800) + (c32 >= 0x10000);
+
+				len -= clen;
+				s8 = (u8 *)&buf[pos];
+
+				/* Avoid writing partial character */
+				PUTC('\0');
+				pos += clen;
+				if (pos >= size)
+					continue;
+
+				/* Set high bits of leading octet */
+				*s8 = (0xf00 >> 1) >> clen;
+				/* Write trailing octets in reverse order */
+				for (s8 += clen; clen; --clen, c32 >>= 6)
+					*s8-- = 0x80 | (c32 & 0x3f);
+				/* Set low bits of leading octet */
+				*s8 |= c32;
+			}
+		} else {
+			while (len-- > 0)
+				PUTC(*s++);
+		}
+		/* Trailing padding with ' ' */
+		while (field_width-- > 0)
+			PUTC(' ');
+	}
+fail:
+	va_end(args);
+
+	if (size)
+		buf[min(pos, size-1)] = '\0';
+
+	return pos;
+}
+
+int snprintf(char *buf, size_t size, const char *fmt, ...)
+{
+	va_list args;
+	int i;
+
+	va_start(args, fmt);
+	i = vsnprintf(buf, size, fmt, args);
+	va_end(args);
+	return i;
+}
diff --git a/drivers/firmware/efi/libstub/x86-stub.c b/drivers/firmware/efi/libstub/x86-stub.c
new file mode 100644
index 000000000..4f0152b11
--- /dev/null
+++ b/drivers/firmware/efi/libstub/x86-stub.c
@@ -0,0 +1,913 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+/* -----------------------------------------------------------------------
+ *
+ *   Copyright 2011 Intel Corporation; author Matt Fleming
+ *
+ * ----------------------------------------------------------------------- */
+
+#include <linux/efi.h>
+#include <linux/pci.h>
+#include <linux/stddef.h>
+
+#include <asm/efi.h>
+#include <asm/e820/types.h>
+#include <asm/setup.h>
+#include <asm/desc.h>
+#include <asm/boot.h>
+
+#include "efistub.h"
+
+/* Maximum physical address for 64-bit kernel with 4-level paging */
+#define MAXMEM_X86_64_4LEVEL (1ull << 46)
+
+const efi_system_table_t *efi_system_table;
+const efi_dxe_services_table_t *efi_dxe_table;
+extern u32 image_offset;
+static efi_loaded_image_t *image = NULL;
+
+static efi_status_t
+preserve_pci_rom_image(efi_pci_io_protocol_t *pci, struct pci_setup_rom **__rom)
+{
+	struct pci_setup_rom *rom = NULL;
+	efi_status_t status;
+	unsigned long size;
+	uint64_t romsize;
+	void *romimage;
+
+	/*
+	 * Some firmware images contain EFI function pointers at the place where
+	 * the romimage and romsize fields are supposed to be. Typically the EFI
+	 * code is mapped at high addresses, translating to an unrealistically
+	 * large romsize. The UEFI spec limits the size of option ROMs to 16
+	 * MiB so we reject any ROMs over 16 MiB in size to catch this.
+	 */
+	romimage = efi_table_attr(pci, romimage);
+	romsize = efi_table_attr(pci, romsize);
+	if (!romimage || !romsize || romsize > SZ_16M)
+		return EFI_INVALID_PARAMETER;
+
+	size = romsize + sizeof(*rom);
+
+	status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, size,
+			     (void **)&rom);
+	if (status != EFI_SUCCESS) {
+		efi_err("Failed to allocate memory for 'rom'\n");
+		return status;
+	}
+
+	memset(rom, 0, sizeof(*rom));
+
+	rom->data.type	= SETUP_PCI;
+	rom->data.len	= size - sizeof(struct setup_data);
+	rom->data.next	= 0;
+	rom->pcilen	= romsize;
+	*__rom = rom;
+
+	status = efi_call_proto(pci, pci.read, EfiPciIoWidthUint16,
+				PCI_VENDOR_ID, 1, &rom->vendor);
+
+	if (status != EFI_SUCCESS) {
+		efi_err("Failed to read rom->vendor\n");
+		goto free_struct;
+	}
+
+	status = efi_call_proto(pci, pci.read, EfiPciIoWidthUint16,
+				PCI_DEVICE_ID, 1, &rom->devid);
+
+	if (status != EFI_SUCCESS) {
+		efi_err("Failed to read rom->devid\n");
+		goto free_struct;
+	}
+
+	status = efi_call_proto(pci, get_location, &rom->segment, &rom->bus,
+				&rom->device, &rom->function);
+
+	if (status != EFI_SUCCESS)
+		goto free_struct;
+
+	memcpy(rom->romdata, romimage, romsize);
+	return status;
+
+free_struct:
+	efi_bs_call(free_pool, rom);
+	return status;
+}
+
+/*
+ * There's no way to return an informative status from this function,
+ * because any analysis (and printing of error messages) needs to be
+ * done directly at the EFI function call-site.
+ *
+ * For example, EFI_INVALID_PARAMETER could indicate a bug or maybe we
+ * just didn't find any PCI devices, but there's no way to tell outside
+ * the context of the call.
+ */
+static void setup_efi_pci(struct boot_params *params)
+{
+	efi_status_t status;
+	void **pci_handle = NULL;
+	efi_guid_t pci_proto = EFI_PCI_IO_PROTOCOL_GUID;
+	unsigned long size = 0;
+	struct setup_data *data;
+	efi_handle_t h;
+	int i;
+
+	status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL,
+			     &pci_proto, NULL, &size, pci_handle);
+
+	if (status == EFI_BUFFER_TOO_SMALL) {
+		status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, size,
+				     (void **)&pci_handle);
+
+		if (status != EFI_SUCCESS) {
+			efi_err("Failed to allocate memory for 'pci_handle'\n");
+			return;
+		}
+
+		status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL,
+				     &pci_proto, NULL, &size, pci_handle);
+	}
+
+	if (status != EFI_SUCCESS)
+		goto free_handle;
+
+	data = (struct setup_data *)(unsigned long)params->hdr.setup_data;
+
+	while (data && data->next)
+		data = (struct setup_data *)(unsigned long)data->next;
+
+	for_each_efi_handle(h, pci_handle, size, i) {
+		efi_pci_io_protocol_t *pci = NULL;
+		struct pci_setup_rom *rom;
+
+		status = efi_bs_call(handle_protocol, h, &pci_proto,
+				     (void **)&pci);
+		if (status != EFI_SUCCESS || !pci)
+			continue;
+
+		status = preserve_pci_rom_image(pci, &rom);
+		if (status != EFI_SUCCESS)
+			continue;
+
+		if (data)
+			data->next = (unsigned long)rom;
+		else
+			params->hdr.setup_data = (unsigned long)rom;
+
+		data = (struct setup_data *)rom;
+	}
+
+free_handle:
+	efi_bs_call(free_pool, pci_handle);
+}
+
+static void retrieve_apple_device_properties(struct boot_params *boot_params)
+{
+	efi_guid_t guid = APPLE_PROPERTIES_PROTOCOL_GUID;
+	struct setup_data *data, *new;
+	efi_status_t status;
+	u32 size = 0;
+	apple_properties_protocol_t *p;
+
+	status = efi_bs_call(locate_protocol, &guid, NULL, (void **)&p);
+	if (status != EFI_SUCCESS)
+		return;
+
+	if (efi_table_attr(p, version) != 0x10000) {
+		efi_err("Unsupported properties proto version\n");
+		return;
+	}
+
+	efi_call_proto(p, get_all, NULL, &size);
+	if (!size)
+		return;
+
+	do {
+		status = efi_bs_call(allocate_pool, EFI_LOADER_DATA,
+				     size + sizeof(struct setup_data),
+				     (void **)&new);
+		if (status != EFI_SUCCESS) {
+			efi_err("Failed to allocate memory for 'properties'\n");
+			return;
+		}
+
+		status = efi_call_proto(p, get_all, new->data, &size);
+
+		if (status == EFI_BUFFER_TOO_SMALL)
+			efi_bs_call(free_pool, new);
+	} while (status == EFI_BUFFER_TOO_SMALL);
+
+	new->type = SETUP_APPLE_PROPERTIES;
+	new->len  = size;
+	new->next = 0;
+
+	data = (struct setup_data *)(unsigned long)boot_params->hdr.setup_data;
+	if (!data) {
+		boot_params->hdr.setup_data = (unsigned long)new;
+	} else {
+		while (data->next)
+			data = (struct setup_data *)(unsigned long)data->next;
+		data->next = (unsigned long)new;
+	}
+}
+
+static void
+adjust_memory_range_protection(unsigned long start, unsigned long size)
+{
+	efi_status_t status;
+	efi_gcd_memory_space_desc_t desc;
+	unsigned long end, next;
+	unsigned long rounded_start, rounded_end;
+	unsigned long unprotect_start, unprotect_size;
+
+	if (efi_dxe_table == NULL)
+		return;
+
+	rounded_start = rounddown(start, EFI_PAGE_SIZE);
+	rounded_end = roundup(start + size, EFI_PAGE_SIZE);
+
+	/*
+	 * Don't modify memory region attributes, they are
+	 * already suitable, to lower the possibility to
+	 * encounter firmware bugs.
+	 */
+
+	for (end = start + size; start < end; start = next) {
+
+		status = efi_dxe_call(get_memory_space_descriptor, start, &desc);
+
+		if (status != EFI_SUCCESS)
+			return;
+
+		next = desc.base_address + desc.length;
+
+		/*
+		 * Only system memory is suitable for trampoline/kernel image placement,
+		 * so only this type of memory needs its attributes to be modified.
+		 */
+
+		if (desc.gcd_memory_type != EfiGcdMemoryTypeSystemMemory ||
+		    (desc.attributes & (EFI_MEMORY_RO | EFI_MEMORY_XP)) == 0)
+			continue;
+
+		unprotect_start = max(rounded_start, (unsigned long)desc.base_address);
+		unprotect_size = min(rounded_end, next) - unprotect_start;
+
+		status = efi_dxe_call(set_memory_space_attributes,
+				      unprotect_start, unprotect_size,
+				      EFI_MEMORY_WB);
+
+		if (status != EFI_SUCCESS) {
+			efi_warn("Unable to unprotect memory range [%08lx,%08lx]: %lx\n",
+				 unprotect_start,
+				 unprotect_start + unprotect_size,
+				 status);
+		}
+	}
+}
+
+/*
+ * Trampoline takes 2 pages and can be loaded in first megabyte of memory
+ * with its end placed between 128k and 640k where BIOS might start.
+ * (see arch/x86/boot/compressed/pgtable_64.c)
+ *
+ * We cannot find exact trampoline placement since memory map
+ * can be modified by UEFI, and it can alter the computed address.
+ */
+
+#define TRAMPOLINE_PLACEMENT_BASE ((128 - 8)*1024)
+#define TRAMPOLINE_PLACEMENT_SIZE (640*1024 - (128 - 8)*1024)
+
+void startup_32(struct boot_params *boot_params);
+
+static void
+setup_memory_protection(unsigned long image_base, unsigned long image_size)
+{
+	/*
+	 * Allow execution of possible trampoline used
+	 * for switching between 4- and 5-level page tables
+	 * and relocated kernel image.
+	 */
+
+	adjust_memory_range_protection(TRAMPOLINE_PLACEMENT_BASE,
+				       TRAMPOLINE_PLACEMENT_SIZE);
+
+#ifdef CONFIG_64BIT
+	if (image_base != (unsigned long)startup_32)
+		adjust_memory_range_protection(image_base, image_size);
+#else
+	/*
+	 * Clear protection flags on a whole range of possible
+	 * addresses used for KASLR. We don't need to do that
+	 * on x86_64, since KASLR/extraction is performed after
+	 * dedicated identity page tables are built and we only
+	 * need to remove possible protection on relocated image
+	 * itself disregarding further relocations.
+	 */
+	adjust_memory_range_protection(LOAD_PHYSICAL_ADDR,
+				       KERNEL_IMAGE_SIZE - LOAD_PHYSICAL_ADDR);
+#endif
+}
+
+static const efi_char16_t apple[] = L"Apple";
+
+static void setup_quirks(struct boot_params *boot_params,
+			 unsigned long image_base,
+			 unsigned long image_size)
+{
+	efi_char16_t *fw_vendor = (efi_char16_t *)(unsigned long)
+		efi_table_attr(efi_system_table, fw_vendor);
+
+	if (!memcmp(fw_vendor, apple, sizeof(apple))) {
+		if (IS_ENABLED(CONFIG_APPLE_PROPERTIES))
+			retrieve_apple_device_properties(boot_params);
+	}
+
+	if (IS_ENABLED(CONFIG_EFI_DXE_MEM_ATTRIBUTES))
+		setup_memory_protection(image_base, image_size);
+}
+
+/*
+ * See if we have Universal Graphics Adapter (UGA) protocol
+ */
+static efi_status_t
+setup_uga(struct screen_info *si, efi_guid_t *uga_proto, unsigned long size)
+{
+	efi_status_t status;
+	u32 width, height;
+	void **uga_handle = NULL;
+	efi_uga_draw_protocol_t *uga = NULL, *first_uga;
+	efi_handle_t handle;
+	int i;
+
+	status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, size,
+			     (void **)&uga_handle);
+	if (status != EFI_SUCCESS)
+		return status;
+
+	status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL,
+			     uga_proto, NULL, &size, uga_handle);
+	if (status != EFI_SUCCESS)
+		goto free_handle;
+
+	height = 0;
+	width = 0;
+
+	first_uga = NULL;
+	for_each_efi_handle(handle, uga_handle, size, i) {
+		efi_guid_t pciio_proto = EFI_PCI_IO_PROTOCOL_GUID;
+		u32 w, h, depth, refresh;
+		void *pciio;
+
+		status = efi_bs_call(handle_protocol, handle, uga_proto,
+				     (void **)&uga);
+		if (status != EFI_SUCCESS)
+			continue;
+
+		pciio = NULL;
+		efi_bs_call(handle_protocol, handle, &pciio_proto, &pciio);
+
+		status = efi_call_proto(uga, get_mode, &w, &h, &depth, &refresh);
+		if (status == EFI_SUCCESS && (!first_uga || pciio)) {
+			width = w;
+			height = h;
+
+			/*
+			 * Once we've found a UGA supporting PCIIO,
+			 * don't bother looking any further.
+			 */
+			if (pciio)
+				break;
+
+			first_uga = uga;
+		}
+	}
+
+	if (!width && !height)
+		goto free_handle;
+
+	/* EFI framebuffer */
+	si->orig_video_isVGA	= VIDEO_TYPE_EFI;
+
+	si->lfb_depth		= 32;
+	si->lfb_width		= width;
+	si->lfb_height		= height;
+
+	si->red_size		= 8;
+	si->red_pos		= 16;
+	si->green_size		= 8;
+	si->green_pos		= 8;
+	si->blue_size		= 8;
+	si->blue_pos		= 0;
+	si->rsvd_size		= 8;
+	si->rsvd_pos		= 24;
+
+free_handle:
+	efi_bs_call(free_pool, uga_handle);
+
+	return status;
+}
+
+static void setup_graphics(struct boot_params *boot_params)
+{
+	efi_guid_t graphics_proto = EFI_GRAPHICS_OUTPUT_PROTOCOL_GUID;
+	struct screen_info *si;
+	efi_guid_t uga_proto = EFI_UGA_PROTOCOL_GUID;
+	efi_status_t status;
+	unsigned long size;
+	void **gop_handle = NULL;
+	void **uga_handle = NULL;
+
+	si = &boot_params->screen_info;
+	memset(si, 0, sizeof(*si));
+
+	size = 0;
+	status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL,
+			     &graphics_proto, NULL, &size, gop_handle);
+	if (status == EFI_BUFFER_TOO_SMALL)
+		status = efi_setup_gop(si, &graphics_proto, size);
+
+	if (status != EFI_SUCCESS) {
+		size = 0;
+		status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL,
+				     &uga_proto, NULL, &size, uga_handle);
+		if (status == EFI_BUFFER_TOO_SMALL)
+			setup_uga(si, &uga_proto, size);
+	}
+}
+
+
+static void __noreturn efi_exit(efi_handle_t handle, efi_status_t status)
+{
+	efi_bs_call(exit, handle, status, 0, NULL);
+	for(;;)
+		asm("hlt");
+}
+
+void __noreturn efi_stub_entry(efi_handle_t handle,
+			       efi_system_table_t *sys_table_arg,
+			       struct boot_params *boot_params);
+
+/*
+ * Because the x86 boot code expects to be passed a boot_params we
+ * need to create one ourselves (usually the bootloader would create
+ * one for us).
+ */
+efi_status_t __efiapi efi_pe_entry(efi_handle_t handle,
+				   efi_system_table_t *sys_table_arg)
+{
+	struct boot_params *boot_params;
+	struct setup_header *hdr;
+	void *image_base;
+	efi_guid_t proto = LOADED_IMAGE_PROTOCOL_GUID;
+	int options_size = 0;
+	efi_status_t status;
+	char *cmdline_ptr;
+
+	efi_system_table = sys_table_arg;
+
+	/* Check if we were booted by the EFI firmware */
+	if (efi_system_table->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE)
+		efi_exit(handle, EFI_INVALID_PARAMETER);
+
+	status = efi_bs_call(handle_protocol, handle, &proto, (void **)&image);
+	if (status != EFI_SUCCESS) {
+		efi_err("Failed to get handle for LOADED_IMAGE_PROTOCOL\n");
+		efi_exit(handle, status);
+	}
+
+	image_base = efi_table_attr(image, image_base);
+	image_offset = (void *)startup_32 - image_base;
+
+	status = efi_allocate_pages(sizeof(struct boot_params),
+				    (unsigned long *)&boot_params, ULONG_MAX);
+	if (status != EFI_SUCCESS) {
+		efi_err("Failed to allocate lowmem for boot params\n");
+		efi_exit(handle, status);
+	}
+
+	memset(boot_params, 0x0, sizeof(struct boot_params));
+
+	hdr = &boot_params->hdr;
+
+	/* Copy the setup header from the second sector to boot_params */
+	memcpy(&hdr->jump, image_base + 512,
+	       sizeof(struct setup_header) - offsetof(struct setup_header, jump));
+
+	/*
+	 * Fill out some of the header fields ourselves because the
+	 * EFI firmware loader doesn't load the first sector.
+	 */
+	hdr->root_flags	= 1;
+	hdr->vid_mode	= 0xffff;
+	hdr->boot_flag	= 0xAA55;
+
+	hdr->type_of_loader = 0x21;
+
+	/* Convert unicode cmdline to ascii */
+	cmdline_ptr = efi_convert_cmdline(image, &options_size);
+	if (!cmdline_ptr)
+		goto fail;
+
+	efi_set_u64_split((unsigned long)cmdline_ptr,
+			  &hdr->cmd_line_ptr, &boot_params->ext_cmd_line_ptr);
+
+	hdr->ramdisk_image = 0;
+	hdr->ramdisk_size = 0;
+
+	/*
+	 * Disregard any setup data that was provided by the bootloader:
+	 * setup_data could be pointing anywhere, and we have no way of
+	 * authenticating or validating the payload.
+	 */
+	hdr->setup_data = 0;
+
+	efi_stub_entry(handle, sys_table_arg, boot_params);
+	/* not reached */
+
+fail:
+	efi_free(sizeof(struct boot_params), (unsigned long)boot_params);
+
+	efi_exit(handle, status);
+}
+
+static void add_e820ext(struct boot_params *params,
+			struct setup_data *e820ext, u32 nr_entries)
+{
+	struct setup_data *data;
+
+	e820ext->type = SETUP_E820_EXT;
+	e820ext->len  = nr_entries * sizeof(struct boot_e820_entry);
+	e820ext->next = 0;
+
+	data = (struct setup_data *)(unsigned long)params->hdr.setup_data;
+
+	while (data && data->next)
+		data = (struct setup_data *)(unsigned long)data->next;
+
+	if (data)
+		data->next = (unsigned long)e820ext;
+	else
+		params->hdr.setup_data = (unsigned long)e820ext;
+}
+
+static efi_status_t
+setup_e820(struct boot_params *params, struct setup_data *e820ext, u32 e820ext_size)
+{
+	struct boot_e820_entry *entry = params->e820_table;
+	struct efi_info *efi = &params->efi_info;
+	struct boot_e820_entry *prev = NULL;
+	u32 nr_entries;
+	u32 nr_desc;
+	int i;
+
+	nr_entries = 0;
+	nr_desc = efi->efi_memmap_size / efi->efi_memdesc_size;
+
+	for (i = 0; i < nr_desc; i++) {
+		efi_memory_desc_t *d;
+		unsigned int e820_type = 0;
+		unsigned long m = efi->efi_memmap;
+
+#ifdef CONFIG_X86_64
+		m |= (u64)efi->efi_memmap_hi << 32;
+#endif
+
+		d = efi_early_memdesc_ptr(m, efi->efi_memdesc_size, i);
+		switch (d->type) {
+		case EFI_RESERVED_TYPE:
+		case EFI_RUNTIME_SERVICES_CODE:
+		case EFI_RUNTIME_SERVICES_DATA:
+		case EFI_MEMORY_MAPPED_IO:
+		case EFI_MEMORY_MAPPED_IO_PORT_SPACE:
+		case EFI_PAL_CODE:
+			e820_type = E820_TYPE_RESERVED;
+			break;
+
+		case EFI_UNUSABLE_MEMORY:
+			e820_type = E820_TYPE_UNUSABLE;
+			break;
+
+		case EFI_ACPI_RECLAIM_MEMORY:
+			e820_type = E820_TYPE_ACPI;
+			break;
+
+		case EFI_LOADER_CODE:
+		case EFI_LOADER_DATA:
+		case EFI_BOOT_SERVICES_CODE:
+		case EFI_BOOT_SERVICES_DATA:
+		case EFI_CONVENTIONAL_MEMORY:
+			if (efi_soft_reserve_enabled() &&
+			    (d->attribute & EFI_MEMORY_SP))
+				e820_type = E820_TYPE_SOFT_RESERVED;
+			else
+				e820_type = E820_TYPE_RAM;
+			break;
+
+		case EFI_ACPI_MEMORY_NVS:
+			e820_type = E820_TYPE_NVS;
+			break;
+
+		case EFI_PERSISTENT_MEMORY:
+			e820_type = E820_TYPE_PMEM;
+			break;
+
+		default:
+			continue;
+		}
+
+		/* Merge adjacent mappings */
+		if (prev && prev->type == e820_type &&
+		    (prev->addr + prev->size) == d->phys_addr) {
+			prev->size += d->num_pages << 12;
+			continue;
+		}
+
+		if (nr_entries == ARRAY_SIZE(params->e820_table)) {
+			u32 need = (nr_desc - i) * sizeof(struct e820_entry) +
+				   sizeof(struct setup_data);
+
+			if (!e820ext || e820ext_size < need)
+				return EFI_BUFFER_TOO_SMALL;
+
+			/* boot_params map full, switch to e820 extended */
+			entry = (struct boot_e820_entry *)e820ext->data;
+		}
+
+		entry->addr = d->phys_addr;
+		entry->size = d->num_pages << PAGE_SHIFT;
+		entry->type = e820_type;
+		prev = entry++;
+		nr_entries++;
+	}
+
+	if (nr_entries > ARRAY_SIZE(params->e820_table)) {
+		u32 nr_e820ext = nr_entries - ARRAY_SIZE(params->e820_table);
+
+		add_e820ext(params, e820ext, nr_e820ext);
+		nr_entries -= nr_e820ext;
+	}
+
+	params->e820_entries = (u8)nr_entries;
+
+	return EFI_SUCCESS;
+}
+
+static efi_status_t alloc_e820ext(u32 nr_desc, struct setup_data **e820ext,
+				  u32 *e820ext_size)
+{
+	efi_status_t status;
+	unsigned long size;
+
+	size = sizeof(struct setup_data) +
+		sizeof(struct e820_entry) * nr_desc;
+
+	if (*e820ext) {
+		efi_bs_call(free_pool, *e820ext);
+		*e820ext = NULL;
+		*e820ext_size = 0;
+	}
+
+	status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, size,
+			     (void **)e820ext);
+	if (status == EFI_SUCCESS)
+		*e820ext_size = size;
+
+	return status;
+}
+
+static efi_status_t allocate_e820(struct boot_params *params,
+				  struct setup_data **e820ext,
+				  u32 *e820ext_size)
+{
+	unsigned long map_size, desc_size, map_key;
+	efi_status_t status;
+	__u32 nr_desc, desc_version;
+
+	/* Only need the size of the mem map and size of each mem descriptor */
+	map_size = 0;
+	status = efi_bs_call(get_memory_map, &map_size, NULL, &map_key,
+			     &desc_size, &desc_version);
+	if (status != EFI_BUFFER_TOO_SMALL)
+		return (status != EFI_SUCCESS) ? status : EFI_UNSUPPORTED;
+
+	nr_desc = map_size / desc_size + EFI_MMAP_NR_SLACK_SLOTS;
+
+	if (nr_desc > ARRAY_SIZE(params->e820_table)) {
+		u32 nr_e820ext = nr_desc - ARRAY_SIZE(params->e820_table);
+
+		status = alloc_e820ext(nr_e820ext, e820ext, e820ext_size);
+		if (status != EFI_SUCCESS)
+			return status;
+	}
+
+	return EFI_SUCCESS;
+}
+
+struct exit_boot_struct {
+	struct boot_params	*boot_params;
+	struct efi_info		*efi;
+};
+
+static efi_status_t exit_boot_func(struct efi_boot_memmap *map,
+				   void *priv)
+{
+	const char *signature;
+	struct exit_boot_struct *p = priv;
+
+	signature = efi_is_64bit() ? EFI64_LOADER_SIGNATURE
+				   : EFI32_LOADER_SIGNATURE;
+	memcpy(&p->efi->efi_loader_signature, signature, sizeof(__u32));
+
+	efi_set_u64_split((unsigned long)efi_system_table,
+			  &p->efi->efi_systab, &p->efi->efi_systab_hi);
+	p->efi->efi_memdesc_size	= map->desc_size;
+	p->efi->efi_memdesc_version	= map->desc_ver;
+	efi_set_u64_split((unsigned long)map->map,
+			  &p->efi->efi_memmap, &p->efi->efi_memmap_hi);
+	p->efi->efi_memmap_size		= map->map_size;
+
+	return EFI_SUCCESS;
+}
+
+static efi_status_t exit_boot(struct boot_params *boot_params, void *handle)
+{
+	struct setup_data *e820ext = NULL;
+	__u32 e820ext_size = 0;
+	efi_status_t status;
+	struct exit_boot_struct priv;
+
+	priv.boot_params	= boot_params;
+	priv.efi		= &boot_params->efi_info;
+
+	status = allocate_e820(boot_params, &e820ext, &e820ext_size);
+	if (status != EFI_SUCCESS)
+		return status;
+
+	/* Might as well exit boot services now */
+	status = efi_exit_boot_services(handle, &priv, exit_boot_func);
+	if (status != EFI_SUCCESS)
+		return status;
+
+	/* Historic? */
+	boot_params->alt_mem_k	= 32 * 1024;
+
+	status = setup_e820(boot_params, e820ext, e820ext_size);
+	if (status != EFI_SUCCESS)
+		return status;
+
+	return EFI_SUCCESS;
+}
+
+/*
+ * On success, we return the address of startup_32, which has potentially been
+ * relocated by efi_relocate_kernel.
+ * On failure, we exit to the firmware via efi_exit instead of returning.
+ */
+asmlinkage unsigned long efi_main(efi_handle_t handle,
+				  efi_system_table_t *sys_table_arg,
+				  struct boot_params *boot_params)
+{
+	unsigned long bzimage_addr = (unsigned long)startup_32;
+	unsigned long buffer_start, buffer_end;
+	struct setup_header *hdr = &boot_params->hdr;
+	const struct linux_efi_initrd *initrd = NULL;
+	efi_status_t status;
+
+	efi_system_table = sys_table_arg;
+	/* Check if we were booted by the EFI firmware */
+	if (efi_system_table->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE)
+		efi_exit(handle, EFI_INVALID_PARAMETER);
+
+	efi_dxe_table = get_efi_config_table(EFI_DXE_SERVICES_TABLE_GUID);
+	if (efi_dxe_table &&
+	    efi_dxe_table->hdr.signature != EFI_DXE_SERVICES_TABLE_SIGNATURE) {
+		efi_warn("Ignoring DXE services table: invalid signature\n");
+		efi_dxe_table = NULL;
+	}
+
+	/*
+	 * If the kernel isn't already loaded at a suitable address,
+	 * relocate it.
+	 *
+	 * It must be loaded above LOAD_PHYSICAL_ADDR.
+	 *
+	 * The maximum address for 64-bit is 1 << 46 for 4-level paging. This
+	 * is defined as the macro MAXMEM, but unfortunately that is not a
+	 * compile-time constant if 5-level paging is configured, so we instead
+	 * define our own macro for use here.
+	 *
+	 * For 32-bit, the maximum address is complicated to figure out, for
+	 * now use KERNEL_IMAGE_SIZE, which will be 512MiB, the same as what
+	 * KASLR uses.
+	 *
+	 * Also relocate it if image_offset is zero, i.e. the kernel wasn't
+	 * loaded by LoadImage, but rather by a bootloader that called the
+	 * handover entry. The reason we must always relocate in this case is
+	 * to handle the case of systemd-boot booting a unified kernel image,
+	 * which is a PE executable that contains the bzImage and an initrd as
+	 * COFF sections. The initrd section is placed after the bzImage
+	 * without ensuring that there are at least init_size bytes available
+	 * for the bzImage, and thus the compressed kernel's startup code may
+	 * overwrite the initrd unless it is moved out of the way.
+	 */
+
+	buffer_start = ALIGN(bzimage_addr - image_offset,
+			     hdr->kernel_alignment);
+	buffer_end = buffer_start + hdr->init_size;
+
+	if ((buffer_start < LOAD_PHYSICAL_ADDR)				     ||
+	    (IS_ENABLED(CONFIG_X86_32) && buffer_end > KERNEL_IMAGE_SIZE)    ||
+	    (IS_ENABLED(CONFIG_X86_64) && buffer_end > MAXMEM_X86_64_4LEVEL) ||
+	    (image_offset == 0)) {
+		extern char _bss[];
+
+		status = efi_relocate_kernel(&bzimage_addr,
+					     (unsigned long)_bss - bzimage_addr,
+					     hdr->init_size,
+					     hdr->pref_address,
+					     hdr->kernel_alignment,
+					     LOAD_PHYSICAL_ADDR);
+		if (status != EFI_SUCCESS) {
+			efi_err("efi_relocate_kernel() failed!\n");
+			goto fail;
+		}
+		/*
+		 * Now that we've copied the kernel elsewhere, we no longer
+		 * have a set up block before startup_32(), so reset image_offset
+		 * to zero in case it was set earlier.
+		 */
+		image_offset = 0;
+	}
+
+#ifdef CONFIG_CMDLINE_BOOL
+	status = efi_parse_options(CONFIG_CMDLINE);
+	if (status != EFI_SUCCESS) {
+		efi_err("Failed to parse options\n");
+		goto fail;
+	}
+#endif
+	if (!IS_ENABLED(CONFIG_CMDLINE_OVERRIDE)) {
+		unsigned long cmdline_paddr = ((u64)hdr->cmd_line_ptr |
+					       ((u64)boot_params->ext_cmd_line_ptr << 32));
+		status = efi_parse_options((char *)cmdline_paddr);
+		if (status != EFI_SUCCESS) {
+			efi_err("Failed to parse options\n");
+			goto fail;
+		}
+	}
+
+	/*
+	 * At this point, an initrd may already have been loaded by the
+	 * bootloader and passed via bootparams. We permit an initrd loaded
+	 * from the LINUX_EFI_INITRD_MEDIA_GUID device path to supersede it.
+	 *
+	 * If the device path is not present, any command-line initrd=
+	 * arguments will be processed only if image is not NULL, which will be
+	 * the case only if we were loaded via the PE entry point.
+	 */
+	status = efi_load_initrd(image, hdr->initrd_addr_max, ULONG_MAX,
+				 &initrd);
+	if (status != EFI_SUCCESS)
+		goto fail;
+	if (initrd && initrd->size > 0) {
+		efi_set_u64_split(initrd->base, &hdr->ramdisk_image,
+				  &boot_params->ext_ramdisk_image);
+		efi_set_u64_split(initrd->size, &hdr->ramdisk_size,
+				  &boot_params->ext_ramdisk_size);
+	}
+
+
+	/*
+	 * If the boot loader gave us a value for secure_boot then we use that,
+	 * otherwise we ask the BIOS.
+	 */
+	if (boot_params->secure_boot == efi_secureboot_mode_unset)
+		boot_params->secure_boot = efi_get_secureboot();
+
+	/* Ask the firmware to clear memory on unclean shutdown */
+	efi_enable_reset_attack_mitigation();
+
+	efi_random_get_seed();
+
+	efi_retrieve_tpm2_eventlog();
+
+	setup_graphics(boot_params);
+
+	setup_efi_pci(boot_params);
+
+	setup_quirks(boot_params, bzimage_addr, buffer_end - buffer_start);
+
+	status = exit_boot(boot_params, handle);
+	if (status != EFI_SUCCESS) {
+		efi_err("exit_boot() failed!\n");
+		goto fail;
+	}
+
+	return bzimage_addr;
+fail:
+	efi_err("efi_main() failed!\n");
+
+	efi_exit(handle, status);
+}
diff --git a/drivers/firmware/efi/libstub/zboot-header.S b/drivers/firmware/efi/libstub/zboot-header.S
new file mode 100644
index 000000000..9e6fe061a
--- /dev/null
+++ b/drivers/firmware/efi/libstub/zboot-header.S
@@ -0,0 +1,143 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#include <linux/pe.h>
+
+#ifdef CONFIG_64BIT
+	.set		.Lextra_characteristics, 0x0
+	.set		.Lpe_opt_magic, PE_OPT_MAGIC_PE32PLUS
+#else
+	.set		.Lextra_characteristics, IMAGE_FILE_32BIT_MACHINE
+	.set		.Lpe_opt_magic, PE_OPT_MAGIC_PE32
+#endif
+
+	.section	".head", "a"
+	.globl		__efistub_efi_zboot_header
+__efistub_efi_zboot_header:
+.Ldoshdr:
+	.long		MZ_MAGIC
+	.ascii		"zimg"					// image type
+	.long		__efistub__gzdata_start - .Ldoshdr	// payload offset
+	.long		__efistub__gzdata_size - ZBOOT_SIZE_LEN	// payload size
+	.long		0, 0					// reserved
+	.asciz		COMP_TYPE				// compression type
+	.org		.Ldoshdr + 0x3c
+	.long		.Lpehdr - .Ldoshdr			// PE header offset
+
+.Lpehdr:
+	.long		PE_MAGIC
+	.short		MACHINE_TYPE
+	.short		.Lsection_count
+	.long		0
+	.long		0
+	.long		0
+	.short		.Lsection_table - .Loptional_header
+	.short		IMAGE_FILE_DEBUG_STRIPPED | \
+			IMAGE_FILE_EXECUTABLE_IMAGE | \
+			IMAGE_FILE_LINE_NUMS_STRIPPED |\
+			.Lextra_characteristics
+
+.Loptional_header:
+	.short		.Lpe_opt_magic
+	.byte		0, 0
+	.long		_etext - .Lefi_header_end
+	.long		__data_size
+	.long		0
+	.long		__efistub_efi_zboot_entry - .Ldoshdr
+	.long		.Lefi_header_end - .Ldoshdr
+
+#ifdef CONFIG_64BIT
+	.quad		0
+#else
+	.long		_etext - .Ldoshdr, 0x0
+#endif
+	.long		4096
+	.long		512
+	.short		0, 0
+	.short		LINUX_EFISTUB_MAJOR_VERSION	// MajorImageVersion
+	.short		LINUX_EFISTUB_MINOR_VERSION	// MinorImageVersion
+	.short		0, 0
+	.long		0
+	.long		_end - .Ldoshdr
+
+	.long		.Lefi_header_end - .Ldoshdr
+	.long		0
+	.short		IMAGE_SUBSYSTEM_EFI_APPLICATION
+	.short		0
+#ifdef CONFIG_64BIT
+	.quad		0, 0, 0, 0
+#else
+	.long		0, 0, 0, 0
+#endif
+	.long		0
+	.long		(.Lsection_table - .) / 8
+
+	.quad		0				// ExportTable
+	.quad		0				// ImportTable
+	.quad		0				// ResourceTable
+	.quad		0				// ExceptionTable
+	.quad		0				// CertificationTable
+	.quad		0				// BaseRelocationTable
+#ifdef CONFIG_DEBUG_EFI
+	.long		.Lefi_debug_table - .Ldoshdr	// DebugTable
+	.long		.Lefi_debug_table_size
+#endif
+
+.Lsection_table:
+	.ascii		".text\0\0\0"
+	.long		_etext - .Lefi_header_end
+	.long		.Lefi_header_end - .Ldoshdr
+	.long		_etext - .Lefi_header_end
+	.long		.Lefi_header_end - .Ldoshdr
+
+	.long		0, 0
+	.short		0, 0
+	.long		IMAGE_SCN_CNT_CODE | \
+			IMAGE_SCN_MEM_READ | \
+			IMAGE_SCN_MEM_EXECUTE
+
+	.ascii		".data\0\0\0"
+	.long		__data_size
+	.long		_etext - .Ldoshdr
+	.long		__data_rawsize
+	.long		_etext - .Ldoshdr
+
+	.long		0, 0
+	.short		0, 0
+	.long		IMAGE_SCN_CNT_INITIALIZED_DATA | \
+			IMAGE_SCN_MEM_READ | \
+			IMAGE_SCN_MEM_WRITE
+
+	.set		.Lsection_count, (. - .Lsection_table) / 40
+
+#ifdef CONFIG_DEBUG_EFI
+	.section	".rodata", "a"
+	.align		2
+.Lefi_debug_table:
+	// EFI_IMAGE_DEBUG_DIRECTORY_ENTRY
+	.long		0				// Characteristics
+	.long		0				// TimeDateStamp
+	.short		0				// MajorVersion
+	.short		0				// MinorVersion
+	.long		IMAGE_DEBUG_TYPE_CODEVIEW	// Type
+	.long		.Lefi_debug_entry_size		// SizeOfData
+	.long		0				// RVA
+	.long		.Lefi_debug_entry - .Ldoshdr	// FileOffset
+
+	.set		.Lefi_debug_table_size, . - .Lefi_debug_table
+	.previous
+
+.Lefi_debug_entry:
+	// EFI_IMAGE_DEBUG_CODEVIEW_NB10_ENTRY
+	.ascii		"NB10"				// Signature
+	.long		0				// Unknown
+	.long		0				// Unknown2
+	.long		0				// Unknown3
+
+	.asciz		ZBOOT_EFI_PATH
+
+	.set		.Lefi_debug_entry_size, . - .Lefi_debug_entry
+#endif
+
+	.p2align	12
+.Lefi_header_end:
+
diff --git a/drivers/firmware/efi/libstub/zboot.c b/drivers/firmware/efi/libstub/zboot.c
new file mode 100644
index 000000000..ea72c8f27
--- /dev/null
+++ b/drivers/firmware/efi/libstub/zboot.c
@@ -0,0 +1,302 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/efi.h>
+#include <linux/pe.h>
+#include <asm/efi.h>
+#include <asm/unaligned.h>
+
+#include "efistub.h"
+
+static unsigned char zboot_heap[SZ_256K] __aligned(64);
+static unsigned long free_mem_ptr, free_mem_end_ptr;
+
+#define STATIC static
+#if defined(CONFIG_KERNEL_GZIP)
+#include "../../../../lib/decompress_inflate.c"
+#elif defined(CONFIG_KERNEL_LZ4)
+#include "../../../../lib/decompress_unlz4.c"
+#elif defined(CONFIG_KERNEL_LZMA)
+#include "../../../../lib/decompress_unlzma.c"
+#elif defined(CONFIG_KERNEL_LZO)
+#include "../../../../lib/decompress_unlzo.c"
+#elif defined(CONFIG_KERNEL_XZ)
+#undef memcpy
+#define memcpy memcpy
+#undef memmove
+#define memmove memmove
+#include "../../../../lib/decompress_unxz.c"
+#elif defined(CONFIG_KERNEL_ZSTD)
+#include "../../../../lib/decompress_unzstd.c"
+#endif
+
+extern char efi_zboot_header[];
+extern char _gzdata_start[], _gzdata_end[];
+
+static void log(efi_char16_t str[])
+{
+	efi_call_proto(efi_table_attr(efi_system_table, con_out),
+		       output_string, L"EFI decompressor: ");
+	efi_call_proto(efi_table_attr(efi_system_table, con_out),
+		       output_string, str);
+	efi_call_proto(efi_table_attr(efi_system_table, con_out),
+		       output_string, L"\n");
+}
+
+static void error(char *x)
+{
+	log(L"error() called from decompressor library\n");
+}
+
+// Local version to avoid pulling in memcmp()
+static bool guids_eq(const efi_guid_t *a, const efi_guid_t *b)
+{
+	const u32 *l = (u32 *)a;
+	const u32 *r = (u32 *)b;
+
+	return l[0] == r[0] && l[1] == r[1] && l[2] == r[2] && l[3] == r[3];
+}
+
+static efi_status_t __efiapi
+load_file(efi_load_file_protocol_t *this, efi_device_path_protocol_t *rem,
+	  bool boot_policy, unsigned long *bufsize, void *buffer)
+{
+	unsigned long compressed_size = _gzdata_end - _gzdata_start;
+	struct efi_vendor_dev_path *vendor_dp;
+	bool decompress = false;
+	unsigned long size;
+	int ret;
+
+	if (rem == NULL || bufsize == NULL)
+		return EFI_INVALID_PARAMETER;
+
+	if (boot_policy)
+		return EFI_UNSUPPORTED;
+
+	// Look for our vendor media device node in the remaining file path
+	if (rem->type == EFI_DEV_MEDIA &&
+	    rem->sub_type == EFI_DEV_MEDIA_VENDOR) {
+		vendor_dp = container_of(rem, struct efi_vendor_dev_path, header);
+		if (!guids_eq(&vendor_dp->vendorguid, &LINUX_EFI_ZBOOT_MEDIA_GUID))
+			return EFI_NOT_FOUND;
+
+		decompress = true;
+		rem = (void *)(vendor_dp + 1);
+	}
+
+	if (rem->type != EFI_DEV_END_PATH ||
+	    rem->sub_type != EFI_DEV_END_ENTIRE)
+		return EFI_NOT_FOUND;
+
+	// The uncompressed size of the payload is appended to the raw bit
+	// stream, and may therefore appear misaligned in memory
+	size = decompress ? get_unaligned_le32(_gzdata_end - 4)
+			  : compressed_size;
+	if (buffer == NULL || *bufsize < size) {
+		*bufsize = size;
+		return EFI_BUFFER_TOO_SMALL;
+	}
+
+	if (decompress) {
+		ret = __decompress(_gzdata_start, compressed_size, NULL, NULL,
+				   buffer, size, NULL, error);
+		if (ret	< 0) {
+			log(L"Decompression failed");
+			return EFI_DEVICE_ERROR;
+		}
+	} else {
+		memcpy(buffer, _gzdata_start, compressed_size);
+	}
+
+	return EFI_SUCCESS;
+}
+
+// Return the length in bytes of the device path up to the first end node.
+static int device_path_length(const efi_device_path_protocol_t *dp)
+{
+	int len = 0;
+
+	while (dp->type != EFI_DEV_END_PATH) {
+		len += dp->length;
+		dp = (void *)((u8 *)dp + dp->length);
+	}
+	return len;
+}
+
+static void append_rel_offset_node(efi_device_path_protocol_t **dp,
+				   unsigned long start, unsigned long end)
+{
+	struct efi_rel_offset_dev_path *rodp = (void *)*dp;
+
+	rodp->header.type	= EFI_DEV_MEDIA;
+	rodp->header.sub_type	= EFI_DEV_MEDIA_REL_OFFSET;
+	rodp->header.length	= sizeof(struct efi_rel_offset_dev_path);
+	rodp->reserved		= 0;
+	rodp->starting_offset	= start;
+	rodp->ending_offset	= end;
+
+	*dp = (void *)(rodp + 1);
+}
+
+static void append_ven_media_node(efi_device_path_protocol_t **dp,
+				  efi_guid_t *guid)
+{
+	struct efi_vendor_dev_path *vmdp = (void *)*dp;
+
+	vmdp->header.type	= EFI_DEV_MEDIA;
+	vmdp->header.sub_type	= EFI_DEV_MEDIA_VENDOR;
+	vmdp->header.length	= sizeof(struct efi_vendor_dev_path);
+	vmdp->vendorguid	= *guid;
+
+	*dp = (void *)(vmdp + 1);
+}
+
+static void append_end_node(efi_device_path_protocol_t **dp)
+{
+	(*dp)->type		= EFI_DEV_END_PATH;
+	(*dp)->sub_type		= EFI_DEV_END_ENTIRE;
+	(*dp)->length		= sizeof(struct efi_generic_dev_path);
+
+	++*dp;
+}
+
+asmlinkage efi_status_t __efiapi
+efi_zboot_entry(efi_handle_t handle, efi_system_table_t *systab)
+{
+	struct efi_mem_mapped_dev_path mmdp = {
+		.header.type		= EFI_DEV_HW,
+		.header.sub_type	= EFI_DEV_MEM_MAPPED,
+		.header.length		= sizeof(struct efi_mem_mapped_dev_path)
+	};
+	efi_device_path_protocol_t *parent_dp, *dpp, *lf2_dp, *li_dp;
+	efi_load_file2_protocol_t zboot_load_file2;
+	efi_loaded_image_t *parent, *child;
+	unsigned long exit_data_size;
+	efi_handle_t child_handle;
+	efi_handle_t zboot_handle;
+	efi_char16_t *exit_data;
+	efi_status_t status;
+	void *dp_alloc;
+	int dp_len;
+
+	WRITE_ONCE(efi_system_table, systab);
+
+	free_mem_ptr = (unsigned long)&zboot_heap;
+	free_mem_end_ptr = free_mem_ptr + sizeof(zboot_heap);
+
+	exit_data = NULL;
+	exit_data_size = 0;
+
+	status = efi_bs_call(handle_protocol, handle,
+			     &LOADED_IMAGE_PROTOCOL_GUID, (void **)&parent);
+	if (status != EFI_SUCCESS) {
+		log(L"Failed to locate parent's loaded image protocol");
+		return status;
+	}
+
+	status = efi_bs_call(handle_protocol, handle,
+			     &LOADED_IMAGE_DEVICE_PATH_PROTOCOL_GUID,
+			     (void **)&parent_dp);
+	if (status != EFI_SUCCESS || parent_dp == NULL) {
+		// Create a MemoryMapped() device path node to describe
+		// the parent image if no device path was provided.
+		mmdp.memory_type	= parent->image_code_type;
+		mmdp.starting_addr	= (unsigned long)parent->image_base;
+		mmdp.ending_addr	= (unsigned long)parent->image_base +
+					  parent->image_size - 1;
+		parent_dp = &mmdp.header;
+		dp_len = sizeof(mmdp);
+	} else {
+		dp_len = device_path_length(parent_dp);
+	}
+
+	// Allocate some pool memory for device path protocol data
+	status = efi_bs_call(allocate_pool, EFI_LOADER_DATA,
+			     2 * (dp_len + sizeof(struct efi_rel_offset_dev_path) +
+			          sizeof(struct efi_generic_dev_path)) +
+			     sizeof(struct efi_vendor_dev_path),
+			     (void **)&dp_alloc);
+	if (status != EFI_SUCCESS) {
+		log(L"Failed to allocate device path pool memory");
+		return status;
+	}
+
+	// Create a device path describing the compressed payload in this image
+	// <...parent_dp...>/Offset(<start>, <end>)
+	lf2_dp = memcpy(dp_alloc, parent_dp, dp_len);
+	dpp = (void *)((u8 *)lf2_dp + dp_len);
+	append_rel_offset_node(&dpp,
+			       (unsigned long)(_gzdata_start - efi_zboot_header),
+			       (unsigned long)(_gzdata_end - efi_zboot_header - 1));
+	append_end_node(&dpp);
+
+	// Create a device path describing the decompressed payload in this image
+	// <...parent_dp...>/Offset(<start>, <end>)/VenMedia(ZBOOT_MEDIA_GUID)
+	dp_len += sizeof(struct efi_rel_offset_dev_path);
+	li_dp = memcpy(dpp, lf2_dp, dp_len);
+	dpp = (void *)((u8 *)li_dp + dp_len);
+	append_ven_media_node(&dpp, &LINUX_EFI_ZBOOT_MEDIA_GUID);
+	append_end_node(&dpp);
+
+	zboot_handle = NULL;
+	zboot_load_file2.load_file = load_file;
+	status = efi_bs_call(install_multiple_protocol_interfaces,
+			     &zboot_handle,
+			     &EFI_DEVICE_PATH_PROTOCOL_GUID, lf2_dp,
+			     &EFI_LOAD_FILE2_PROTOCOL_GUID, &zboot_load_file2,
+			     NULL);
+	if (status != EFI_SUCCESS) {
+		log(L"Failed to install LoadFile2 protocol and device path");
+		goto free_dpalloc;
+	}
+
+	status = efi_bs_call(load_image, false, handle, li_dp, NULL, 0,
+			     &child_handle);
+	if (status != EFI_SUCCESS) {
+		log(L"Failed to load image");
+		goto uninstall_lf2;
+	}
+
+	status = efi_bs_call(handle_protocol, child_handle,
+			     &LOADED_IMAGE_PROTOCOL_GUID, (void **)&child);
+	if (status != EFI_SUCCESS) {
+		log(L"Failed to locate child's loaded image protocol");
+		goto unload_image;
+	}
+
+	// Copy the kernel command line
+	child->load_options = parent->load_options;
+	child->load_options_size = parent->load_options_size;
+
+	status = efi_bs_call(start_image, child_handle, &exit_data_size,
+			     &exit_data);
+	if (status != EFI_SUCCESS) {
+		log(L"StartImage() returned with error");
+		if (exit_data_size > 0)
+			log(exit_data);
+
+		// If StartImage() returns EFI_SECURITY_VIOLATION, the image is
+		// not unloaded so we need to do it by hand.
+		if (status == EFI_SECURITY_VIOLATION)
+unload_image:
+			efi_bs_call(unload_image, child_handle);
+	}
+
+uninstall_lf2:
+	efi_bs_call(uninstall_multiple_protocol_interfaces,
+		    zboot_handle,
+		    &EFI_DEVICE_PATH_PROTOCOL_GUID, lf2_dp,
+		    &EFI_LOAD_FILE2_PROTOCOL_GUID, &zboot_load_file2,
+		    NULL);
+
+free_dpalloc:
+	efi_bs_call(free_pool, dp_alloc);
+
+	efi_bs_call(exit, handle, status, exit_data_size, exit_data);
+
+	// Free ExitData in case Exit() returned with a failure code,
+	// but return the original status code.
+	log(L"Exit() returned with failure code");
+	if (exit_data != NULL)
+		efi_bs_call(free_pool, exit_data);
+	return status;
+}
diff --git a/drivers/firmware/efi/libstub/zboot.lds b/drivers/firmware/efi/libstub/zboot.lds
new file mode 100644
index 000000000..93d33f683
--- /dev/null
+++ b/drivers/firmware/efi/libstub/zboot.lds
@@ -0,0 +1,45 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+ENTRY(__efistub_efi_zboot_header);
+
+SECTIONS
+{
+	.head : ALIGN(4096) {
+		*(.head)
+	}
+
+	.text : {
+		*(.text* .init.text*)
+	}
+
+	.rodata : ALIGN(8) {
+		__efistub__gzdata_start = .;
+		*(.gzdata)
+		__efistub__gzdata_end = .;
+		*(.rodata* .init.rodata* .srodata*)
+		_etext = ALIGN(4096);
+		. = _etext;
+	}
+
+	.data : ALIGN(4096) {
+		*(.data* .init.data*)
+		_edata = ALIGN(512);
+		. = _edata;
+	}
+
+	.bss : {
+		*(.bss* .init.bss*)
+		_end = ALIGN(512);
+		. = _end;
+	}
+
+	/DISCARD/ : {
+		*(.modinfo .init.modinfo)
+	}
+}
+
+PROVIDE(__efistub__gzdata_size =
+		ABSOLUTE(__efistub__gzdata_end - __efistub__gzdata_start));
+
+PROVIDE(__data_rawsize = ABSOLUTE(_edata - _etext));
+PROVIDE(__data_size = ABSOLUTE(_end - _etext));