linux/arch/arm/boot/compressed/head-shmobile.S
Magnus Damm 2c408d1492 ARM: shmobile: Update romImage to relocate appended DTB
Instead of relying of MACH_TYPE for board identification,
update the romImage code to relocate an appended DTB to
the beginning of RAM. This implementation is independent
of ARM_APPENDED_DTB, this because it is necessary to copy
the DTB to memory so the kernel can access it.

Without this patch Mackerel does not boot via the Mask ROM
over USB (r_usb_boot) - this since non-DT boot was broken
ages ago in commit:

0ce53cd ARM: mach-shmobile: Use DT_MACHINE for mackerel

Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
2013-07-17 10:04:36 +09:00

102 lines
2.4 KiB
ArmAsm

/*
* The head-file for SH-Mobile ARM platforms
*
* Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
* Simon Horman <horms@verge.net.au>
*
* 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifdef CONFIG_ZBOOT_ROM
.section ".start", "ax"
/* load board-specific initialization code */
#include <mach/zboot.h>
#if defined(CONFIG_ZBOOT_ROM_MMCIF) || defined(CONFIG_ZBOOT_ROM_SH_MOBILE_SDHI)
/* Load image from MMC/SD */
adr sp, __tmp_stack + 256
ldr r0, __image_start
ldr r1, __image_end
subs r1, r1, r0
ldr r0, __load_base
bl mmc_loader
/* Jump to loaded code */
ldr r0, __loaded
ldr r1, __image_start
sub r0, r0, r1
ldr r1, __load_base
add pc, r0, r1
__image_start:
.long _start
__image_end:
.long _got_end
__load_base:
.long MEMORY_START + 0x02000000 @ Load at 32Mb into SDRAM
__loaded:
.long __continue
.align
__tmp_stack:
.space 256
__continue:
#endif /* CONFIG_ZBOOT_ROM_MMC || CONFIG_ZBOOT_ROM_SH_MOBILE_SDHI */
adr r0, dtb_info
ldmia r0, {r1, r3, r4, r5, r7}
sub r0, r0, r1 @ calculate the delta offset
add r5, r5, r0 @ _edata
ldr lr, [r5, #0] @ check if valid DTB is present
cmp lr, r3
bne 0f
add r9, r7, #31 @ rounded up to a multiple
bic r9, r9, #31 @ ... of 32 bytes
add r6, r9, r5 @ copy from _edata
add r9, r9, r4 @ to MEMORY_START
1: ldmdb r6!, {r0 - r3, r10 - r12, lr}
cmp r6, r5
stmdb r9!, {r0 - r3, r10 - r12, lr}
bhi 1b
/* Success: Zero board ID, pointer to start of memory for atag/dtb */
mov r7, #0
mov r8, r4
b 2f
.align 2
dtb_info:
.word dtb_info
#ifndef __ARMEB__
.word 0xedfe0dd0 @ sig is 0xd00dfeed big endian
#else
.word 0xd00dfeed
#endif
.word MEMORY_START
.word _edata
.word 0x4000 @ maximum DTB size
0:
/* Failure: Zero board ID, NULL atag/dtb */
mov r7, #0
mov r8, #0 @ pass null pointer as atag
2 :
#endif /* CONFIG_ZBOOT_ROM */