94 lines
		
	
	
		
			2.3 KiB
		
	
	
	
		
			ArmAsm
		
	
	
	
			
		
		
	
	
			94 lines
		
	
	
		
			2.3 KiB
		
	
	
	
		
			ArmAsm
		
	
	
	
| /*
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|  *  armboot - Startup Code for OMP2420/ARM1136 CPU-core
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|  *
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|  *  Copyright (c) 2004	Texas Instruments <r-woodruff2@ti.com>
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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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|  *
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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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| 
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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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| 	/* the mask ROM code should have PLL and others stable */
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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 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	/* Invalidate I+D+BTB caches */
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| 	mcr	p15, 0, r0, c8, c7, 0	/* Invalidate Unified TLB */
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| 
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| 	/*
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| 	 * disable MMU stuff and caches
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| 	 */
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| 	mrc	p15, 0, r0, c1, c0, 0
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| 	bic	r0, r0, #0x00002300	@ clear bits 13, 9:8 (--V- --RS)
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| 	bic	r0, r0, #0x00000087	@ clear bits 7, 2:0 (B--- -CAM)
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| 	orr	r0, r0, #0x00000002	@ set bit 2 (A) Align
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| 	orr	r0, r0, #0x00001000	@ set bit 12 (I) I-Cache
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| 	mcr	p15, 0, r0, c1, c0, 0
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| 
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| 	/*
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| 	 * Jump to board specific initialization... The Mask ROM will have already initialized
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| 	 * basic memory.  Go here to bump up clock rate and handle wake up conditions.
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| 	 */
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| 	mov	ip, lr		/* persevere 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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