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