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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /drivers/firmware/efi/libstub/arm64.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/firmware/efi/libstub/arm64.c')
-rw-r--r--drivers/firmware/efi/libstub/arm64.c140
1 files changed, 140 insertions, 0 deletions
diff --git a/drivers/firmware/efi/libstub/arm64.c b/drivers/firmware/efi/libstub/arm64.c
new file mode 100644
index 0000000000..446e35eaf3
--- /dev/null
+++ b/drivers/firmware/efi/libstub/arm64.c
@@ -0,0 +1,140 @@
+// 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/image.h>
+#include <asm/memory.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;
+}
+
+#ifdef CONFIG_ARM64_WORKAROUND_CLEAN_CACHE
+#define DCTYPE "civac"
+#else
+#define DCTYPE "cvau"
+#endif
+
+u32 __weak code_size;
+
+void efi_cache_sync_image(unsigned long image_base,
+ unsigned long alloc_size)
+{
+ u32 ctr = read_cpuid_effective_cachetype();
+ u64 lsize = 4 << cpuid_feature_extract_unsigned_field(ctr,
+ CTR_EL0_DminLine_SHIFT);
+
+ /* only perform the cache maintenance if needed for I/D coherency */
+ if (!(ctr & BIT(CTR_EL0_IDC_SHIFT))) {
+ unsigned long base = image_base;
+ unsigned long size = code_size;
+
+ do {
+ asm("dc " DCTYPE ", %0" :: "r"(base));
+ base += lsize;
+ size -= lsize;
+ } while (size >= lsize);
+ }
+
+ asm("ic ialluis");
+ dsb(ish);
+ isb();
+
+ efi_remap_image(image_base, alloc_size, code_size);
+}
+
+unsigned long __weak primary_entry_offset(void)
+{
+ /*
+ * By default, we can invoke the kernel via the branch instruction in
+ * the image header, so offset #0. This will be overridden by the EFI
+ * stub build that is linked into the core kernel, as in that case, the
+ * image header may not have been loaded into memory, or may be mapped
+ * with non-executable permissions.
+ */
+ return 0;
+}
+
+void __noreturn efi_enter_kernel(unsigned long entrypoint,
+ unsigned long fdt_addr,
+ unsigned long fdt_size)
+{
+ void (* __noreturn enter_kernel)(u64, u64, u64, u64);
+
+ enter_kernel = (void *)entrypoint + primary_entry_offset();
+ enter_kernel(fdt_addr, 0, 0, 0);
+}