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	This option allows skipping the call to lowlevel() while still performing CP15 init. Support this on ARM720T so it can be used with Tegra. Signed-off-by: Simon Glass <sjg@chromium.org>
		
			
				
	
	
		
			81 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
			
		
		
	
	
			81 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
| /*
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|  *  armboot - Startup Code for ARM720 CPU-core
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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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|  *
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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 RAM!
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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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| 
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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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| #if !defined(CONFIG_SKIP_LOWLEVEL_INIT) && \
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| 		!defined(CONFIG_SKIP_LOWLEVEL_INIT_ONLY)
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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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| 	mov	pc, 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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| 
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| #if !defined(CONFIG_SKIP_LOWLEVEL_INIT) && \
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| 		!defined(CONFIG_SKIP_LOWLEVEL_INIT_ONLY)
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| cpu_init_crit:
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| 
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| 	mov	ip, lr
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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-dependent, you will
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| 	 * find a lowlevel_init.S in your board directory.
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| 	 */
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| 	bl	lowlevel_init
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| 	mov	lr, ip
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| 
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| 	mov	pc, lr
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| #endif /* CONFIG_SKIP_LOWLEVEL_INIT */
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