linux-sg2042/arch/arm/boot/compressed/head-clps7500.S

87 lines
1.8 KiB
ArmAsm

/*
* linux/arch/arm/boot/compressed/head.S
*
* Copyright (C) 1999, 2000, 2001 Nexus Electronics Ltd
*/
/* 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"