[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>
diff --git a/arch/powerpc/boot/wrapper b/arch/powerpc/boot/wrapper
index 03b474b..087e120 100755
--- a/arch/powerpc/boot/wrapper
+++ b/arch/powerpc/boot/wrapper
@@ -298,15 +298,16 @@
exit 0
;;
ps3)
- # The ps3's loader supports loading gzipped binary images from flash
- # rom to addr zero. The loader enters the image at addr 0x100. A
- # bootwrapper overlay is use to arrange for the kernel to be loaded
- # to addr zero and to have a suitable bootwrapper entry at 0x100.
- # To construct the rom image, 0x100 bytes from offset 0x100 in the
- # kernel is copied to the bootwrapper symbol __system_reset_kernel.
- # The 0x100 bytes at the bootwrapper symbol __system_reset_overlay is
- # then copied to offset 0x100. At runtime the bootwrapper program
- # copies the 0x100 bytes at __system_reset_kernel to addr 0x100.
+ # The ps3's loader supports loading a gzipped binary image from flash
+ # rom to ram addr zero. The loader then enters the system reset
+ # vector at addr 0x100. A bootwrapper overlay is used to arrange for
+ # a binary image of the kernel to be at addr zero, and yet have a
+ # suitable bootwrapper entry at 0x100. To construct the final rom
+ # image 512 bytes from offset 0x100 is copied to the bootwrapper
+ # place holder at symbol __system_reset_kernel. The 512 bytes of the
+ # bootwrapper entry code at symbol __system_reset_overlay is then
+ # copied to offset 0x100. At runtime the bootwrapper program copies
+ # the data at __system_reset_kernel back to addr 0x100.
system_reset_overlay=0x`${CROSS}nm "$ofile" \
| grep ' __system_reset_overlay$' \
@@ -317,7 +318,7 @@
| cut -d' ' -f1`
system_reset_kernel=`printf "%d" $system_reset_kernel`
overlay_dest="256"
- overlay_size="256"
+ overlay_size="512"
${CROSS}objcopy -O binary "$ofile" "$ofile.bin"