diff options
author | Geoff Levand <geoffrey.levand@am.sony.com> | 2008-03-27 23:41:45 +0300 |
---|---|---|
committer | Paul Mackerras <paulus@samba.org> | 2008-04-01 13:43:07 +0400 |
commit | 5761eaa3a5ae3c7ea796add73b86176b7c963cca (patch) | |
tree | 8b2b5f292059738216202b4b5480cdc02bd925d0 /arch/powerpc/boot/ps3-head.S | |
parent | 23afcb4e0061c591776a3350db89512d085397c2 (diff) | |
download | linux-5761eaa3a5ae3c7ea796add73b86176b7c963cca.tar.xz |
[POWERPC] PS3: Bootwrapper improvements
Improve the debugging support of the PS3 bootwraper code:
o Increase the size of the PS3 bootwrapper overlay from 256 to 512 bytes to
allow for more debugging code in the overlay.
o Use the dot symbol to set the size of __system_reset_overlay. The
assembler will then emit an error if the overlay code is too big.
o Remove some unused instructions.
o Update the text describing the PS3 bootwrapper overlay.
o Add a check for null pointer writes.
o Change hcall return value from s64.
Signed-off-by: Geoff Levand <geoffrey.levand@am.sony.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Diffstat (limited to 'arch/powerpc/boot/ps3-head.S')
-rw-r--r-- | arch/powerpc/boot/ps3-head.S | 25 |
1 files changed, 16 insertions, 9 deletions
diff --git a/arch/powerpc/boot/ps3-head.S b/arch/powerpc/boot/ps3-head.S index a55c2735f759..b6fcbaf5027b 100644 --- a/arch/powerpc/boot/ps3-head.S +++ b/arch/powerpc/boot/ps3-head.S @@ -27,8 +27,9 @@ /* * __system_reset_overlay - The PS3 first stage entry. * - * The bootwraper build script copies the 0x100 bytes at symbol - * __system_reset_overlay to offset 0x100 of the rom image. + * The bootwraper build script copies the 512 bytes at symbol + * __system_reset_overlay to offset 0x100 of the rom image. This symbol + * must occupy 512 or less bytes. * * The PS3 has a single processor with two threads. */ @@ -47,8 +48,6 @@ __system_reset_overlay: mfspr r3, 0x88 cntlzw. r3, r3 - li r4, 0 - li r5, 0 beq 1f /* Secondary goes to __secondary_hold in kernel. */ @@ -57,8 +56,14 @@ __system_reset_overlay: mtctr r4 bctr - /* Primary delays then goes to _zimage_start in wrapper. */ 1: + /* Save the value at addr zero for a null pointer write check later. */ + + li r4, 0 + lwz r3, 0(r4) + + /* Primary delays then goes to _zimage_start in wrapper. */ + or 31, 31, 31 /* db16cyc */ or 31, 31, 31 /* db16cyc */ @@ -67,16 +72,18 @@ __system_reset_overlay: mtctr r4 bctr + . = __system_reset_overlay + 512 + /* * __system_reset_kernel - Place holder for the kernel reset vector. * - * The bootwrapper build script copies 0x100 bytes from offset 0x100 + * The bootwrapper build script copies 512 bytes from offset 0x100 * of the rom image to the symbol __system_reset_kernel. At runtime - * the bootwrapper program copies the 0x100 bytes at __system_reset_kernel - * to ram address 0x100. This symbol must occupy 0x100 bytes. + * the bootwrapper program copies the 512 bytes at __system_reset_kernel + * to ram address 0x100. This symbol must occupy 512 bytes. */ .globl __system_reset_kernel __system_reset_kernel: - . = __system_reset_kernel + 0x100 + . = __system_reset_kernel + 512 |