diff options
Diffstat (limited to 'arch/arm/boot/compressed/head.S')
-rw-r--r-- | arch/arm/boot/compressed/head.S | 57 |
1 files changed, 42 insertions, 15 deletions
diff --git a/arch/arm/boot/compressed/head.S b/arch/arm/boot/compressed/head.S index a36f4526689b..c363458a4e63 100644 --- a/arch/arm/boot/compressed/head.S +++ b/arch/arm/boot/compressed/head.S @@ -179,16 +179,29 @@ not_angel: bl cache_on restart: adr r0, LC0 - ldmia r0, {r1, r2, r3, r5, r6, r9, r11, r12} - ldr sp, [r0, #32] + ldmia r0, {r1, r2, r3, r6, r10, r11, r12} + ldr sp, [r0, #28] /* * We might be running at a different address. We need * to fix up various pointers. */ sub r0, r0, r1 @ calculate the delta offset - add r5, r5, r0 @ _start add r6, r6, r0 @ _edata + add r10, r10, r0 @ inflated kernel size location + + /* + * The kernel build system appends the size of the + * decompressed kernel at the end of the compressed data + * in little-endian form. + */ + ldrb r9, [r10, #0] + ldrb lr, [r10, #1] + orr r9, r9, lr, lsl #8 + ldrb lr, [r10, #2] + ldrb r10, [r10, #3] + orr r9, r9, lr, lsl #16 + orr r9, r9, r10, lsl #24 #ifndef CONFIG_ZBOOT_ROM /* malloc space is above the relocated stack (64k max) */ @@ -206,31 +219,40 @@ restart: adr r0, LC0 /* * Check to see if we will overwrite ourselves. * r4 = final kernel address - * r5 = start of this image * r9 = size of decompressed image * r10 = end of this image, including bss/stack/malloc space if non XIP * We basically want: - * r4 >= r10 -> OK - * r4 + image length <= r5 -> OK + * r4 - 16k page directory >= r10 -> OK + * r4 + image length <= current position (pc) -> OK */ + add r10, r10, #16384 cmp r4, r10 bhs wont_overwrite add r10, r4, r9 - cmp r10, r5 + ARM( cmp r10, pc ) + THUMB( mov lr, pc ) + THUMB( cmp r10, lr ) bls wont_overwrite /* * Relocate ourselves past the end of the decompressed kernel. - * r5 = start of this image * r6 = _edata * r10 = end of the decompressed kernel * Because we always copy ahead, we need to do it from the end and go * backward in case the source and destination overlap. */ - /* Round up to next 256-byte boundary. */ - add r10, r10, #256 + /* + * Bump to the next 256-byte boundary with the size of + * the relocation code added. This avoids overwriting + * ourself when the offset is small. + */ + add r10, r10, #((reloc_code_end - restart + 256) & ~255) bic r10, r10, #255 + /* Get start of code we want to copy and align it down. */ + adr r5, restart + bic r5, r5, #31 + sub r9, r6, r5 @ size to copy add r9, r9, #31 @ rounded up to a multiple bic r9, r9, #31 @ ... of 32 bytes @@ -245,6 +267,11 @@ restart: adr r0, LC0 /* Preserve offset to relocated code. */ sub r6, r9, r6 +#ifndef CONFIG_ZBOOT_ROM + /* cache_clean_flush may use the stack, so relocate it */ + add sp, sp, r6 +#endif + bl cache_clean_flush adr r0, BSYM(restart) @@ -333,12 +360,11 @@ not_relocated: mov r0, #0 LC0: .word LC0 @ r1 .word __bss_start @ r2 .word _end @ r3 - .word _start @ r5 .word _edata @ r6 - .word _image_size @ r9 + .word input_data_end - 4 @ r10 (inflated size location) .word _got_start @ r11 .word _got_end @ ip - .word user_stack_end @ sp + .word .L_user_stack_end @ sp .size LC0, . - LC0 #ifdef CONFIG_ARCH_RPC @@ -1056,8 +1082,9 @@ memdump: mov r12, r0 #endif .ltorg +reloc_code_end: .align .section ".stack", "aw", %nobits -user_stack: .space 4096 -user_stack_end: +.L_user_stack: .space 4096 +.L_user_stack_end: |