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-rw-r--r--arch/powerpc/boot/crt0.S116
-rwxr-xr-xarch/powerpc/boot/wrapper9
-rw-r--r--arch/powerpc/boot/zImage.coff.lds.S6
-rw-r--r--arch/powerpc/boot/zImage.lds.S57
4 files changed, 118 insertions, 70 deletions
diff --git a/arch/powerpc/boot/crt0.S b/arch/powerpc/boot/crt0.S
index f1c4dfc635be..0f7428a37efb 100644
--- a/arch/powerpc/boot/crt0.S
+++ b/arch/powerpc/boot/crt0.S
@@ -6,16 +6,28 @@
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
- * NOTE: this code runs in 32 bit mode and is packaged as ELF32.
+ * NOTE: this code runs in 32 bit mode, is position-independent,
+ * and is packaged as ELF32.
*/
#include "ppc_asm.h"
.text
- /* a procedure descriptor used when booting this as a COFF file */
+ /* A procedure descriptor used when booting this as a COFF file.
+ * When making COFF, this comes first in the link and we're
+ * linked at 0x500000.
+ */
.globl _zimage_start_opd
_zimage_start_opd:
- .long _zimage_start, 0, 0, 0
+ .long 0x500000, 0, 0, 0
+
+p_start: .long _start
+p_etext: .long _etext
+p_bss_start: .long __bss_start
+p_end: .long _end
+
+ .weak _platform_stack_top
+p_pstack: .long _platform_stack_top
.weak _zimage_start
.globl _zimage_start
@@ -24,37 +36,65 @@ _zimage_start:
_zimage_start_lib:
/* Work out the offset between the address we were linked at
and the address where we're running. */
- bl 1f
-1: mflr r0
- lis r9,1b@ha
- addi r9,r9,1b@l
- subf. r0,r9,r0
- beq 3f /* if running at same address as linked */
+ bl .+4
+p_base: mflr r10 /* r10 now points to runtime addr of p_base */
+ /* grab the link address of the dynamic section in r11 */
+ addis r11,r10,(_GLOBAL_OFFSET_TABLE_-p_base)@ha
+ lwz r11,(_GLOBAL_OFFSET_TABLE_-p_base)@l(r11)
+ cmpwi r11,0
+ beq 3f /* if not linked -pie */
+ /* get the runtime address of the dynamic section in r12 */
+ .weak __dynamic_start
+ addis r12,r10,(__dynamic_start-p_base)@ha
+ addi r12,r12,(__dynamic_start-p_base)@l
+ subf r11,r11,r12 /* runtime - linktime offset */
+
+ /* The dynamic section contains a series of tagged entries.
+ * We need the RELA and RELACOUNT entries. */
+RELA = 7
+RELACOUNT = 0x6ffffff9
+ li r9,0
+ li r0,0
+9: lwz r8,0(r12) /* get tag */
+ cmpwi r8,0
+ beq 10f /* end of list */
+ cmpwi r8,RELA
+ bne 11f
+ lwz r9,4(r12) /* get RELA pointer in r9 */
+ b 12f
+11: addis r8,r8,(-RELACOUNT)@ha
+ cmpwi r8,RELACOUNT@l
+ bne 12f
+ lwz r0,4(r12) /* get RELACOUNT value in r0 */
+12: addi r12,r12,8
+ b 9b
- /* The .got2 section contains a list of addresses, so add
- the address offset onto each entry. */
- lis r9,__got2_start@ha
- addi r9,r9,__got2_start@l
- lis r8,__got2_end@ha
- addi r8,r8,__got2_end@l
- subf. r8,r9,r8
+ /* The relocation section contains a list of relocations.
+ * We now do the R_PPC_RELATIVE ones, which point to words
+ * which need to be initialized with addend + offset.
+ * The R_PPC_RELATIVE ones come first and there are RELACOUNT
+ * of them. */
+10: /* skip relocation if we don't have both */
+ cmpwi r0,0
beq 3f
- srwi. r8,r8,2
- mtctr r8
- add r9,r0,r9
-2: lwz r8,0(r9)
- add r8,r8,r0
- stw r8,0(r9)
- addi r9,r9,4
+ cmpwi r9,0
+ beq 3f
+
+ add r9,r9,r11 /* Relocate RELA pointer */
+ mtctr r0
+2: lbz r0,4+3(r9) /* ELF32_R_INFO(reloc->r_info) */
+ cmpwi r0,22 /* R_PPC_RELATIVE */
+ bne 3f
+ lwz r12,0(r9) /* reloc->r_offset */
+ lwz r0,8(r9) /* reloc->r_addend */
+ add r0,r0,r11
+ stwx r0,r11,r12
+ addi r9,r9,12
bdnz 2b
/* Do a cache flush for our text, in case the loader didn't */
-3: lis r9,_start@ha
- addi r9,r9,_start@l
- add r9,r0,r9
- lis r8,_etext@ha
- addi r8,r8,_etext@l
- add r8,r0,r8
+3: lwz r9,p_start-p_base(r10) /* note: these are relocated now */
+ lwz r8,p_etext-p_base(r10)
4: dcbf r0,r9
icbi r0,r9
addi r9,r9,0x20
@@ -64,27 +104,19 @@ _zimage_start_lib:
isync
/* Clear the BSS */
- lis r9,__bss_start@ha
- addi r9,r9,__bss_start@l
- add r9,r0,r9
- lis r8,_end@ha
- addi r8,r8,_end@l
- add r8,r0,r8
- li r10,0
-5: stw r10,0(r9)
+ lwz r9,p_bss_start-p_base(r10)
+ lwz r8,p_end-p_base(r10)
+ li r0,0
+5: stw r0,0(r9)
addi r9,r9,4
cmplw cr0,r9,r8
blt 5b
/* Possibly set up a custom stack */
-.weak _platform_stack_top
- lis r8,_platform_stack_top@ha
- addi r8,r8,_platform_stack_top@l
+ lwz r8,p_pstack-p_base(r10)
cmpwi r8,0
beq 6f
- add r8,r0,r8
lwz r1,0(r8)
- add r1,r0,r1
li r0,0
stwu r0,-16(r1) /* establish a stack frame */
6:
diff --git a/arch/powerpc/boot/wrapper b/arch/powerpc/boot/wrapper
index cb97e7511d7e..fef527867811 100755
--- a/arch/powerpc/boot/wrapper
+++ b/arch/powerpc/boot/wrapper
@@ -39,6 +39,7 @@ dts=
cacheit=
binary=
gzip=.gz
+pie=
# cross-compilation prefix
CROSS=
@@ -157,9 +158,10 @@ pmac|chrp)
platformo=$object/of.o
;;
coff)
- platformo=$object/of.o
+ platformo="$object/crt0.o $object/of.o"
lds=$object/zImage.coff.lds
link_address='0x500000'
+ pie=
;;
miboot|uboot)
# miboot and U-boot want just the bare bits, not an ELF binary
@@ -208,6 +210,7 @@ ps3)
ksection=.kernel:vmlinux.bin
isection=.kernel:initrd
link_address=''
+ pie=
;;
ep88xc|ep405|ep8248e)
platformo="$object/fixed-head.o $object/$platform.o"
@@ -310,9 +313,9 @@ fi
if [ "$platform" != "miboot" ]; then
if [ -n "$link_address" ] ; then
- text_start="-Ttext $link_address --defsym _start=$link_address"
+ text_start="-Ttext $link_address"
fi
- ${CROSS}ld -m elf32ppc -T $lds $text_start -o "$ofile" \
+ ${CROSS}ld -m elf32ppc -T $lds $text_start $pie -o "$ofile" \
$platformo $tmp $object/wrapper.a
rm $tmp
fi
diff --git a/arch/powerpc/boot/zImage.coff.lds.S b/arch/powerpc/boot/zImage.coff.lds.S
index 856dc78b14ef..de4c9e3c9344 100644
--- a/arch/powerpc/boot/zImage.coff.lds.S
+++ b/arch/powerpc/boot/zImage.coff.lds.S
@@ -3,13 +3,13 @@ ENTRY(_zimage_start_opd)
EXTERN(_zimage_start_opd)
SECTIONS
{
- _start = .;
.text :
{
+ _start = .;
*(.text)
*(.fixup)
+ _etext = .;
}
- _etext = .;
. = ALIGN(4096);
.data :
{
@@ -17,9 +17,7 @@ SECTIONS
*(.data*)
*(__builtin_*)
*(.sdata*)
- __got2_start = .;
*(.got2)
- __got2_end = .;
_dtb_start = .;
*(.kernel:dtb)
diff --git a/arch/powerpc/boot/zImage.lds.S b/arch/powerpc/boot/zImage.lds.S
index 0962d62bdb50..2bd8731f1365 100644
--- a/arch/powerpc/boot/zImage.lds.S
+++ b/arch/powerpc/boot/zImage.lds.S
@@ -3,49 +3,64 @@ ENTRY(_zimage_start)
EXTERN(_zimage_start)
SECTIONS
{
- _start = .;
.text :
{
+ _start = .;
*(.text)
*(.fixup)
+ _etext = .;
}
- _etext = .;
. = ALIGN(4096);
.data :
{
*(.rodata*)
*(.data*)
*(.sdata*)
- __got2_start = .;
*(.got2)
- __got2_end = .;
}
+ .dynsym : { *(.dynsym) }
+ .dynstr : { *(.dynstr) }
+ .dynamic :
+ {
+ __dynamic_start = .;
+ *(.dynamic)
+ }
+ .hash : { *(.hash) }
+ .interp : { *(.interp) }
+ .rela.dyn : { *(.rela*) }
. = ALIGN(8);
- _dtb_start = .;
- .kernel:dtb : { *(.kernel:dtb) }
- _dtb_end = .;
-
- . = ALIGN(4096);
- _vmlinux_start = .;
- .kernel:vmlinux.strip : { *(.kernel:vmlinux.strip) }
- _vmlinux_end = .;
+ .kernel:dtb :
+ {
+ _dtb_start = .;
+ *(.kernel:dtb)
+ _dtb_end = .;
+ }
. = ALIGN(4096);
- _initrd_start = .;
- .kernel:initrd : { *(.kernel:initrd) }
- _initrd_end = .;
+ .kernel:vmlinux.strip :
+ {
+ _vmlinux_start = .;
+ *(.kernel:vmlinux.strip)
+ _vmlinux_end = .;
+ }
. = ALIGN(4096);
- _edata = .;
+ .kernel:initrd :
+ {
+ _initrd_start = .;
+ *(.kernel:initrd)
+ _initrd_end = .;
+ }
. = ALIGN(4096);
- __bss_start = .;
.bss :
{
- *(.sbss)
- *(.bss)
+ _edata = .;
+ __bss_start = .;
+ *(.sbss)
+ *(.bss)
+ *(COMMON)
+ _end = . ;
}
- . = ALIGN(4096);
- _end = . ;
}