112 lines
		
	
	
		
			2.7 KiB
		
	
	
	
		
			ArmAsm
		
	
	
	
			
		
		
	
	
			112 lines
		
	
	
		
			2.7 KiB
		
	
	
	
		
			ArmAsm
		
	
	
	
| /*
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|  *  armboot - Startup Code for ARM926EJS CPU-core
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|  *
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|  *  Copyright (c) 2003  Texas Instruments
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|  *
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|  *  ----- Adapted for OMAP1610 OMAP730 from ARM925t code ------
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|  *
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|  *  Copyright (c) 2001	Marius Gröger <mag@sysgo.de>
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|  *  Copyright (c) 2002	Alex Züpke <azu@sysgo.de>
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|  *  Copyright (c) 2002	Gary Jennejohn <garyj@denx.de>
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|  *  Copyright (c) 2003	Richard Woodruff <r-woodruff2@ti.com>
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|  *  Copyright (c) 2003	Kshitij <kshitij@ti.com>
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|  *  Copyright (c) 2010	Albert Aribaud <albert.u.boot@aribaud.net>
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|  *
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|  * SPDX-License-Identifier:	GPL-2.0+
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|  */
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| 
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| #include <asm-offsets.h>
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| #include <config.h>
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| #include <common.h>
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| 
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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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|  * setup Memory and board specific bits prior to relocation.
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|  * relocate armboot to ram
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|  * setup stack
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|  *
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|  *************************************************************************
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|  */
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| 
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| 	.globl	reset
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| 
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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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| 	/*
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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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| 
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| 	bl	_main
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| 
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| /*------------------------------------------------------------------------------*/
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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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| 
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| 	bx	lr
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| 
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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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| #ifndef CONFIG_SKIP_LOWLEVEL_INIT
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| cpu_init_crit:
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| 	/*
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| 	 * flush D cache before disabling it
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| 	 */
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| 	mov	r0, #0
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| flush_dcache:
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| 	mrc	p15, 0, r15, c7, c10, 3
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| 	bne	flush_dcache
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| 
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| 	mcr	p15, 0, r0, c8, c7, 0	/* invalidate TLB */
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| 	mcr	p15, 0, r0, c7, c5, 0	/* invalidate I Cache */
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| 
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| 	/*
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| 	 * disable MMU and D cache
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| 	 * enable I cache if CONFIG_SYS_ICACHE_OFF is not defined
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| 	 */
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| 	mrc	p15, 0, r0, c1, c0, 0
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| 	bic	r0, r0, #0x00000300	/* clear bits 9:8 (---- --RS) */
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| 	bic	r0, r0, #0x00000087	/* clear bits 7, 2:0 (B--- -CAM) */
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| #ifdef CONFIG_SYS_EXCEPTION_VECTORS_HIGH
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| 	orr	r0, r0, #0x00002000	/* set bit 13 (--V- ----) */
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| #else
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| 	bic	r0, r0, #0x00002000	/* clear bit 13 (--V- ----) */
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| #endif
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| 	orr	r0, r0, #0x00000002	/* set bit 1 (A) Align */
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| #ifndef CONFIG_SYS_ICACHE_OFF
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| 	orr	r0, r0, #0x00001000	/* set bit 12 (I) I-Cache */
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| #endif
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| 	mcr	p15, 0, r0, c1, c0, 0
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| 
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| 	/*
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| 	 * Go setup Memory and board specific bits prior to relocation.
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| 	 */
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| 	mov	ip, lr		/* perserve link reg across call */
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| 	bl	lowlevel_init	/* go setup pll,mux,memory */
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| 	mov	lr, ip		/* restore link */
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| 	mov	pc, lr		/* back to my caller */
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| #endif /* CONFIG_SKIP_LOWLEVEL_INIT */
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