127 lines
2.5 KiB
ArmAsm
127 lines
2.5 KiB
ArmAsm
/* SPDX-License-Identifier: GPL-2.0+ */
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/*
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* armboot - Startup Code for SA1100 CPU
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*
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* Copyright (C) 1998 Dan Malek <dmalek@jlc.net>
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* Copyright (C) 1999 Magnus Damm <kieraypc01.p.y.kie.era.ericsson.se>
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* Copyright (C) 2000 Wolfgang Denk <wd@denx.de>
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* Copyright (c) 2001 Alex Züpke <azu@sysgo.de>
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*/
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#include <asm-offsets.h>
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#include <config.h>
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/*
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*************************************************************************
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*
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* Startup Code (reset vector)
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*
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* do important init only if we don't start from memory!
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* relocate armboot to ram
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* setup stack
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* jump to second stage
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*
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*************************************************************************
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*/
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.globl reset
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reset:
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/*
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* set the cpu to SVC32 mode
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*/
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mrs r0,cpsr
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bic r0,r0,#0x1f
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orr r0,r0,#0xd3
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msr cpsr,r0
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/*
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* we do sys-critical inits only at reboot,
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* not when booting from ram!
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*/
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#ifndef CONFIG_SKIP_LOWLEVEL_INIT
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bl cpu_init_crit
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#endif
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bl _main
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/*------------------------------------------------------------------------------*/
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.globl c_runtime_cpu_setup
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c_runtime_cpu_setup:
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mov pc, lr
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/*
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*************************************************************************
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*
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* CPU_init_critical registers
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*
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* setup important registers
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* setup memory timing
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*
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*************************************************************************
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*/
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/* Interrupt-Controller base address */
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IC_BASE: .word 0x90050000
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#define ICMR 0x04
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/* Reset-Controller */
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RST_BASE: .word 0x90030000
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#define RSRR 0x00
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#define RCSR 0x04
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/* PWR */
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PWR_BASE: .word 0x90020000
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#define PSPR 0x08
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#define PPCR 0x14
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cpuspeed: .word CONFIG_SYS_CPUSPEED
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cpu_init_crit:
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/*
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* mask all IRQs
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*/
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ldr r0, IC_BASE
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mov r1, #0x00
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str r1, [r0, #ICMR]
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/* set clock speed */
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ldr r0, PWR_BASE
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ldr r1, cpuspeed
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str r1, [r0, #PPCR]
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#ifndef CONFIG_SKIP_LOWLEVEL_INIT_ONLY
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/*
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* before relocating, we have to setup RAM timing
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* because memory timing is board-dependend, you will
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* find a lowlevel_init.S in your board directory.
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*/
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mov ip, lr
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bl lowlevel_init
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mov lr, ip
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#endif
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/*
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* disable MMU stuff and enable I-cache
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*/
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mrc p15,0,r0,c1,c0
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bic r0, r0, #0x00002000 @ clear bit 13 (X)
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bic r0, r0, #0x0000000f @ clear bits 3-0 (WCAM)
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orr r0, r0, #0x00001000 @ set bit 12 (I) Icache
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orr r0, r0, #0x00000002 @ set bit 1 (A) Align
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mcr p15,0,r0,c1,c0
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/*
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* flush v4 I/D caches
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*/
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mov r0, #0
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mcr p15, 0, r0, c7, c7, 0 /* flush v3/v4 cache */
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mcr p15, 0, r0, c8, c7, 0 /* flush v4 TLB */
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mov pc, lr
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