1 files changed, 78 insertions, 0 deletions
diff --git a/arch/arm/kernel/relocate_kernel.S b/arch/arm/kernel/relocate_kernel.S
new file mode 100644
index 000000000..218d52436
--- /dev/null
+++ b/arch/arm/kernel/relocate_kernel.S
@@ -0,0 +1,78 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * relocate_kernel.S - put the kernel image in place to boot
+ */
+
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+#include <asm/asm-offsets.h>
+#include <asm/kexec.h>
+
+	.align	3	/* not needed for this code, but keeps fncpy() happy */
+
+ENTRY(relocate_new_kernel)
+
+	adr	r7, relocate_new_kernel_end
+	ldr	r0, [r7, #KEXEC_INDIR_PAGE]
+	ldr	r1, [r7, #KEXEC_START_ADDR]
+
+	/*
+	 * If there is no indirection page (we are doing crashdumps)
+	 * skip any relocation.
+	 */
+	cmp	r0, #0
+	beq	2f
+
+0:	/* top, read another word for the indirection page */
+	ldr	r3, [r0],#4
+
+	/* Is it a destination page. Put destination address to r4 */
+	tst	r3,#1
+	beq	1f
+	bic	r4,r3,#1
+	b	0b
+1:
+	/* Is it an indirection page */
+	tst	r3,#2
+	beq	1f
+	bic	r0,r3,#2
+	b	0b
+1:
+
+	/* are we done ? */
+	tst	r3,#4
+	beq	1f
+	b	2f
+
+1:
+	/* is it source ? */
+	tst	r3,#8
+	beq	0b
+	bic r3,r3,#8
+	mov r6,#1024
+9:
+	ldr r5,[r3],#4
+	str r5,[r4],#4
+	subs r6,r6,#1
+	bne 9b
+	b 0b
+
+2:
+	/* Jump to relocated kernel */
+	mov	lr, r1
+	mov	r0, #0
+	ldr	r1, [r7, #KEXEC_MACH_TYPE]
+	ldr	r2, [r7, #KEXEC_R2]
+ ARM(	ret	lr	)
+ THUMB(	bx	lr	)
+
+ENDPROC(relocate_new_kernel)
+
+	.align	3
+relocate_new_kernel_end:
+
+	.globl relocate_new_kernel_size
+relocate_new_kernel_size:
+	.long relocate_new_kernel_end - relocate_new_kernel
+
+