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-rw-r--r--arch/arm64/kernel/relocate_kernel.S121
1 files changed, 47 insertions, 74 deletions
diff --git a/arch/arm64/kernel/relocate_kernel.S b/arch/arm64/kernel/relocate_kernel.S
index 542d6edc6806..413f899e4ac6 100644
--- a/arch/arm64/kernel/relocate_kernel.S
+++ b/arch/arm64/kernel/relocate_kernel.S
@@ -4,6 +4,8 @@
*
* Copyright (C) Linaro.
* Copyright (C) Huawei Futurewei Technologies.
+ * Copyright (C) 2021, Microsoft Corporation.
+ * Pasha Tatashin <pasha.tatashin@soleen.com>
*/
#include <linux/kexec.h>
@@ -13,115 +15,86 @@
#include <asm/kexec.h>
#include <asm/page.h>
#include <asm/sysreg.h>
+#include <asm/virt.h>
+.macro turn_off_mmu tmp1, tmp2
+ mov_q \tmp1, INIT_SCTLR_EL1_MMU_OFF
+ pre_disable_mmu_workaround
+ msr sctlr_el1, \tmp1
+ isb
+.endm
+
+.section ".kexec_relocate.text", "ax"
/*
* arm64_relocate_new_kernel - Put a 2nd stage image in place and boot it.
*
- * The memory that the old kernel occupies may be overwritten when coping the
+ * The memory that the old kernel occupies may be overwritten when copying the
* new image to its final location. To assure that the
* arm64_relocate_new_kernel routine which does that copy is not overwritten,
* all code and data needed by arm64_relocate_new_kernel must be between the
* symbols arm64_relocate_new_kernel and arm64_relocate_new_kernel_end. The
* machine_kexec() routine will copy arm64_relocate_new_kernel to the kexec
- * control_code_page, a special page which has been set up to be preserved
- * during the copy operation.
+ * safe memory that has been set up to be preserved during the copy operation.
*/
SYM_CODE_START(arm64_relocate_new_kernel)
+ /*
+ * The kimage structure isn't allocated specially and may be clobbered
+ * during relocation. We must load any values we need from it prior to
+ * any relocation occurring.
+ */
+ ldr x28, [x0, #KIMAGE_START]
+ ldr x27, [x0, #KIMAGE_ARCH_EL2_VECTORS]
+ ldr x26, [x0, #KIMAGE_ARCH_DTB_MEM]
/* Setup the list loop variables. */
- mov x18, x2 /* x18 = dtb address */
- mov x17, x1 /* x17 = kimage_start */
- mov x16, x0 /* x16 = kimage_head */
- raw_dcache_line_size x15, x0 /* x15 = dcache line size */
- mov x14, xzr /* x14 = entry ptr */
- mov x13, xzr /* x13 = copy dest */
-
- /* Clear the sctlr_el2 flags. */
- mrs x0, CurrentEL
- cmp x0, #CurrentEL_EL2
- b.ne 1f
- mrs x0, sctlr_el2
- mov_q x1, SCTLR_ELx_FLAGS
- bic x0, x0, x1
- pre_disable_mmu_workaround
- msr sctlr_el2, x0
- isb
-1:
-
- /* Check if the new image needs relocation. */
- tbnz x16, IND_DONE_BIT, .Ldone
-
+ ldr x18, [x0, #KIMAGE_ARCH_ZERO_PAGE] /* x18 = zero page for BBM */
+ ldr x17, [x0, #KIMAGE_ARCH_TTBR1] /* x17 = linear map copy */
+ ldr x16, [x0, #KIMAGE_HEAD] /* x16 = kimage_head */
+ ldr x22, [x0, #KIMAGE_ARCH_PHYS_OFFSET] /* x22 phys_offset */
+ raw_dcache_line_size x15, x1 /* x15 = dcache line size */
+ break_before_make_ttbr_switch x18, x17, x1, x2 /* set linear map */
.Lloop:
and x12, x16, PAGE_MASK /* x12 = addr */
-
+ sub x12, x12, x22 /* Convert x12 to virt */
/* Test the entry flags. */
.Ltest_source:
tbz x16, IND_SOURCE_BIT, .Ltest_indirection
/* Invalidate dest page to PoC. */
- mov x0, x13
- add x20, x0, #PAGE_SIZE
- sub x1, x15, #1
- bic x0, x0, x1
-2: dc ivac, x0
- add x0, x0, x15
- cmp x0, x20
- b.lo 2b
- dsb sy
-
- mov x20, x13
- mov x21, x12
- copy_page x20, x21, x0, x1, x2, x3, x4, x5, x6, x7
-
- /* dest += PAGE_SIZE */
- add x13, x13, PAGE_SIZE
+ mov x19, x13
+ copy_page x13, x12, x1, x2, x3, x4, x5, x6, x7, x8
+ add x1, x19, #PAGE_SIZE
+ dcache_by_myline_op civac, sy, x19, x1, x15, x20
b .Lnext
-
.Ltest_indirection:
tbz x16, IND_INDIRECTION_BIT, .Ltest_destination
-
- /* ptr = addr */
- mov x14, x12
+ mov x14, x12 /* ptr = addr */
b .Lnext
-
.Ltest_destination:
tbz x16, IND_DESTINATION_BIT, .Lnext
-
- /* dest = addr */
- mov x13, x12
-
+ mov x13, x12 /* dest = addr */
.Lnext:
- /* entry = *ptr++ */
- ldr x16, [x14], #8
-
- /* while (!(entry & DONE)) */
- tbz x16, IND_DONE_BIT, .Lloop
-
-.Ldone:
+ ldr x16, [x14], #8 /* entry = *ptr++ */
+ tbz x16, IND_DONE_BIT, .Lloop /* while (!(entry & DONE)) */
/* wait for writes from copy_page to finish */
dsb nsh
ic iallu
dsb nsh
isb
+ turn_off_mmu x12, x13
/* Start new image. */
- mov x0, x18
+ cbz x27, .Lel1
+ mov x1, x28 /* kernel entry point */
+ mov x2, x26 /* dtb address */
+ mov x3, xzr
+ mov x4, xzr
+ mov x0, #HVC_SOFT_RESTART
+ hvc #0 /* Jumps from el2 */
+.Lel1:
+ mov x0, x26 /* dtb address */
mov x1, xzr
mov x2, xzr
mov x3, xzr
- br x17
-
+ br x28 /* Jumps from el1 */
SYM_CODE_END(arm64_relocate_new_kernel)
-
-.align 3 /* To keep the 64-bit values below naturally aligned. */
-
-.Lcopy_end:
-.org KEXEC_CONTROL_PAGE_SIZE
-
-/*
- * arm64_relocate_new_kernel_size - Number of bytes to copy to the
- * control_code_page.
- */
-.globl arm64_relocate_new_kernel_size
-arm64_relocate_new_kernel_size:
- .quad .Lcopy_end - arm64_relocate_new_kernel