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-rw-r--r--arch/ppc/kernel/relocate_kernel.S123
1 files changed, 123 insertions, 0 deletions
diff --git a/arch/ppc/kernel/relocate_kernel.S b/arch/ppc/kernel/relocate_kernel.S
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+++ b/arch/ppc/kernel/relocate_kernel.S
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+/*
+ * relocate_kernel.S - put the kernel image in place to boot
+ * Copyright (C) 2002-2003 Eric Biederman <ebiederm@xmission.com>
+ *
+ * GameCube/ppc32 port Copyright (C) 2004 Albert Herranz
+ *
+ * This source code is licensed under the GNU General Public License,
+ * Version 2. See the file COPYING for more details.
+ */
+
+#include <asm/reg.h>
+#include <asm/ppc_asm.h>
+#include <asm/processor.h>
+
+#include <asm/kexec.h>
+
+#define PAGE_SIZE 4096 /* must be same value as in <asm/page.h> */
+
+ /*
+ * Must be relocatable PIC code callable as a C function.
+ */
+ .globl relocate_new_kernel
+relocate_new_kernel:
+ /* r3 = page_list */
+ /* r4 = reboot_code_buffer */
+ /* r5 = start_address */
+
+ li r0, 0
+
+ /*
+ * Set Machine Status Register to a known status,
+ * switch the MMU off and jump to 1: in a single step.
+ */
+
+ mr r8, r0
+ ori r8, r8, MSR_RI|MSR_ME
+ mtspr SRR1, r8
+ addi r8, r4, 1f - relocate_new_kernel
+ mtspr SRR0, r8
+ sync
+ rfi
+
+1:
+ /* from this point address translation is turned off */
+ /* and interrupts are disabled */
+
+ /* set a new stack at the bottom of our page... */
+ /* (not really needed now) */
+ addi r1, r4, KEXEC_CONTROL_CODE_SIZE - 8 /* for LR Save+Back Chain */
+ stw r0, 0(r1)
+
+ /* Do the copies */
+ li r6, 0 /* checksum */
+ mr r0, r3
+ b 1f
+
+0: /* top, read another word for the indirection page */
+ lwzu r0, 4(r3)
+
+1:
+ /* is it a destination page? (r8) */
+ rlwinm. r7, r0, 0, 31, 31 /* IND_DESTINATION (1<<0) */
+ beq 2f
+
+ rlwinm r8, r0, 0, 0, 19 /* clear kexec flags, page align */
+ b 0b
+
+2: /* is it an indirection page? (r3) */
+ rlwinm. r7, r0, 0, 30, 30 /* IND_INDIRECTION (1<<1) */
+ beq 2f
+
+ rlwinm r3, r0, 0, 0, 19 /* clear kexec flags, page align */
+ subi r3, r3, 4
+ b 0b
+
+2: /* are we done? */
+ rlwinm. r7, r0, 0, 29, 29 /* IND_DONE (1<<2) */
+ beq 2f
+ b 3f
+
+2: /* is it a source page? (r9) */
+ rlwinm. r7, r0, 0, 28, 28 /* IND_SOURCE (1<<3) */
+ beq 0b
+
+ rlwinm r9, r0, 0, 0, 19 /* clear kexec flags, page align */
+
+ li r7, PAGE_SIZE / 4
+ mtctr r7
+ subi r9, r9, 4
+ subi r8, r8, 4
+9:
+ lwzu r0, 4(r9) /* do the copy */
+ xor r6, r6, r0
+ stwu r0, 4(r8)
+ dcbst 0, r8
+ sync
+ icbi 0, r8
+ bdnz 9b
+
+ addi r9, r9, 4
+ addi r8, r8, 4
+ b 0b
+
+3:
+
+ /* To be certain of avoiding problems with self-modifying code
+ * execute a serializing instruction here.
+ */
+ isync
+ sync
+
+ /* jump to the entry point, usually the setup routine */
+ mtlr r5
+ blrl
+
+1: b 1b
+
+relocate_new_kernel_end:
+
+ .globl relocate_new_kernel_size
+relocate_new_kernel_size:
+ .long relocate_new_kernel_end - relocate_new_kernel
+