openwrt/target/linux/mpc85xx/image/spi-loader/head.S
Matthias Schiffer a296055b82 mpc85xx: add SPI kernel loader for TP-Link TL-WDR4900 v1
Similar to the lzma-loader on our MIPS targets, the spi-loader acts as
a second-stage loader that will then load and start the actual kernel.
As the TL-WDR4900 uses SPI-NOR and the P1010 family does not have support
for memory mapping of this type of flash, this loader needs to contain a
basic driver for the FSL ESPI controller.

Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net>
2022-10-14 23:13:02 +02:00

37 lines
684 B
ArmAsm

/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
* Copyright (C) 2022 Matthias Schiffer <mschiffer@universe-factory.net>
*
* Based on Linux arch/powerpc/boot/crt0.S, which is:
*
* Copyright (C) Paul Mackerras 1997.
*/
#include <ppc_asm.h>
.text
.global _start
_start:
/* Do a cache flush for our text, in case the loader didn't */
lis r3,_text_start@ha
addi r3,r3,_text_start@l
li r4,_text_len
bl flush_cache
/* Clear the BSS */
lis r3,_bss_start@ha
addi r3,r3,_bss_start@l
li r4,0
li r5,_bss_len
bl memset
/* Set up stack */
lis r1,_stack_top@ha
addi r1,r1,_stack_top@l
/* Establish a stack frame */
li r0,0
stwu r0,-16(r1)
/* Call start */
b start