mirror of https://gitee.com/openkylin/linux.git
88 lines
1.8 KiB
ArmAsm
88 lines
1.8 KiB
ArmAsm
/*
|
|
* linux/arch/arm/boot/compressed/head.S
|
|
*
|
|
* Copyright (C) 1999, 2000, 2001 Nexus Electronics Ltd
|
|
*/
|
|
|
|
#include <linux/config.h>
|
|
|
|
/* There are three different ways the kernel can be
|
|
booted on a 7500 system: from Angel (loaded in RAM), from
|
|
16-bit ROM or from 32-bit Flash. Luckily, a single kernel
|
|
image does for them all. */
|
|
/* This branch is taken if the CPU memory width matches the
|
|
actual device in use. The default at power on is 16 bits
|
|
so we must be prepared for a mismatch. */
|
|
.section ".start", "ax"
|
|
2:
|
|
b 1f
|
|
.word 0xffff
|
|
.word 0xb632 @ mov r11, #0x03200000
|
|
.word 0xe3a0
|
|
.word 0x0000 @ mov r0, #0
|
|
.word 0xe3a0
|
|
.word 0x0080 @ strb r0, [r11, #0x80]
|
|
.word 0xe5cb
|
|
.word 0xf000 @ mov pc, #0
|
|
.word 0xe3a0
|
|
1:
|
|
adr r1, 2b
|
|
teq r1, #0
|
|
bne .Langel
|
|
/* This is a direct-from-ROM boot. Copy the kernel into
|
|
RAM and run it there. */
|
|
mov r0, #0x30
|
|
mcr p15, 0, r0, c1, c0, 0
|
|
mov r0, #0x13
|
|
msr cpsr_cxsf, r0
|
|
mov r12, #0x03000000 @ point to LEDs
|
|
orr r12, r12, #0x00020000
|
|
orr r12, r12, #0xba00
|
|
mov r0, #0x5500
|
|
str r0, [r12]
|
|
mov r0, #0x10000000
|
|
orr r0, r0, #0x8000
|
|
mov r4, r0
|
|
ldr r2, =_end
|
|
2:
|
|
ldr r3, [r1], #4
|
|
str r3, [r0], #4
|
|
teq r0, r2
|
|
bne 2b
|
|
mov r0, #0xff00
|
|
str r0, [r12]
|
|
1:
|
|
mov r12, #0x03000000 @ point to LEDs
|
|
orr r12, r12, #0x00020000
|
|
orr r12, r12, #0xba00
|
|
mov r0, #0xfe00
|
|
str r0, [r12]
|
|
|
|
adr lr, 1f
|
|
mov r0, #0
|
|
mov r1, #14 /* MACH_TYPE_CLPS7500 */
|
|
mov pc, lr
|
|
.Langel:
|
|
#ifdef CONFIG_ANGELBOOT
|
|
/* Call Angel to switch into SVC mode. */
|
|
mov r0, #0x17
|
|
swi 0x123456
|
|
#endif
|
|
/* Ensure all interrupts are off and MMU disabled */
|
|
mrs r0, cpsr
|
|
orr r0, r0, #0xc0
|
|
msr cpsr_cxsf, r0
|
|
|
|
adr lr, 1b
|
|
orr lr, lr, #0x10000000
|
|
mov r0, #0x30 @ MMU off
|
|
mcr p15, 0, r0, c1, c0, 0
|
|
mov r0, r0
|
|
mov pc, lr
|
|
|
|
.ltorg
|
|
|
|
1:
|
|
/* And the rest */
|
|
#include "head.S"
|