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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /arch/arm64/kernel/efi-entry.S
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/arm64/kernel/efi-entry.S')
-rw-r--r--arch/arm64/kernel/efi-entry.S69
1 files changed, 69 insertions, 0 deletions
diff --git a/arch/arm64/kernel/efi-entry.S b/arch/arm64/kernel/efi-entry.S
new file mode 100644
index 000000000..61a87fa1c
--- /dev/null
+++ b/arch/arm64/kernel/efi-entry.S
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+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * EFI entry point.
+ *
+ * Copyright (C) 2013, 2014 Red Hat, Inc.
+ * Author: Mark Salter <msalter@redhat.com>
+ */
+#include <linux/linkage.h>
+#include <linux/init.h>
+
+#include <asm/assembler.h>
+
+ __INIT
+
+SYM_CODE_START(efi_enter_kernel)
+ /*
+ * efi_pe_entry() will have copied the kernel image if necessary and we
+ * end up here with device tree address in x1 and the kernel entry
+ * point stored in x0. Save those values in registers which are
+ * callee preserved.
+ */
+ ldr w2, =primary_entry_offset
+ add x19, x0, x2 // relocated Image entrypoint
+ mov x20, x1 // DTB address
+
+ /*
+ * Clean the copied Image to the PoC, and ensure it is not shadowed by
+ * stale icache entries from before relocation.
+ */
+ ldr w1, =kernel_size
+ add x1, x0, x1
+ bl dcache_clean_poc
+ ic ialluis
+
+ /*
+ * Clean the remainder of this routine to the PoC
+ * so that we can safely disable the MMU and caches.
+ */
+ adr x0, 0f
+ adr x1, 3f
+ bl dcache_clean_poc
+0:
+ /* Turn off Dcache and MMU */
+ mrs x0, CurrentEL
+ cmp x0, #CurrentEL_EL2
+ b.ne 1f
+ mrs x0, sctlr_el2
+ bic x0, x0, #1 << 0 // clear SCTLR.M
+ bic x0, x0, #1 << 2 // clear SCTLR.C
+ pre_disable_mmu_workaround
+ msr sctlr_el2, x0
+ isb
+ b 2f
+1:
+ mrs x0, sctlr_el1
+ bic x0, x0, #1 << 0 // clear SCTLR.M
+ bic x0, x0, #1 << 2 // clear SCTLR.C
+ pre_disable_mmu_workaround
+ msr sctlr_el1, x0
+ isb
+2:
+ /* Jump to kernel entry point */
+ mov x0, x20
+ mov x1, xzr
+ mov x2, xzr
+ mov x3, xzr
+ br x19
+3:
+SYM_CODE_END(efi_enter_kernel)