linux/arch/powerpc/boot/ps3-head.S
Geoff Levand 5761eaa3a5 [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>
2008-04-01 20:43:07 +11:00

89 lines
2.2 KiB
ArmAsm

/*
* PS3 bootwrapper entry.
*
* Copyright (C) 2007 Sony Computer Entertainment Inc.
* Copyright 2007 Sony Corp.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include "ppc_asm.h"
.machine "ppc64"
.text
/*
* __system_reset_overlay - The PS3 first stage entry.
*
* 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.
*/
.globl __system_reset_overlay
__system_reset_overlay:
/* Switch to 32-bit mode. */
mfmsr r9
clrldi r9,r9,1
mtmsrd r9
nop
/* Get thread number in r3 and branch. */
mfspr r3, 0x88
cntlzw. r3, r3
beq 1f
/* Secondary goes to __secondary_hold in kernel. */
li r4, 0x60
mtctr r4
bctr
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 */
lis r4, _zimage_start@ha
addi r4, r4, _zimage_start@l
mtctr r4
bctr
. = __system_reset_overlay + 512
/*
* __system_reset_kernel - Place holder for the kernel reset vector.
*
* 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 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 + 512