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	Relocate the u-boot image into SDRAM like everyone else does. This means that we can handle much larger .data and .bss than we used to. Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
		
			
				
	
	
		
			165 lines
		
	
	
		
			3.5 KiB
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
			
		
		
	
	
			165 lines
		
	
	
		
			3.5 KiB
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
/*
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 * Copyright (C) 2005-2006 Atmel Corporation
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 *
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 * See file CREDITS for list of people who contributed to this
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 * project.
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 *
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 * This program is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU General Public License as
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 * published by the Free Software Foundation; either version 2 of
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 * the License, or (at your option) any later version.
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 *
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 * This program is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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 * GNU General Public License for more details.
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 *
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 * You should have received a copy of the GNU General Public License
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 * along with this program; if not, write to the Free Software
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 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
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 * MA 02111-1307 USA
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 */
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#include <config.h>
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#include <asm/sysreg.h>
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#ifndef PART_SPECIFIC_BOOTSTRAP
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# define PART_SPECIFIC_BOOTSTRAP
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#endif
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#define SYSREG_MMUCR_I_OFFSET	2
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#define SYSREG_MMUCR_S_OFFSET	4
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#define SR_INIT (SYSREG_BIT(GM) | SYSREG_BIT(EM) | SYSREG_BIT(M0))
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#define CPUCR_INIT (SYSREG_BIT(BI) | SYSREG_BIT(BE)		\
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		    | SYSREG_BIT(FE) | SYSREG_BIT(RE)		\
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		    | SYSREG_BIT(IBE) | SYSREG_BIT(IEE))
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	.text
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	.global	_start
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_start:
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	PART_SPECIFIC_BOOTSTRAP
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	/* Reset the Status Register */
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	mov	r0, lo(SR_INIT)
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	orh	r0, hi(SR_INIT)
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	mtsr	SYSREG_SR, r0
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	/* Reset CPUCR and invalidate the BTB */
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	mov	r2, CPUCR_INIT
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	mtsr	SYSREG_CPUCR, r2
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	/* Flush the caches */
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	mov	r1, 0
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	cache	r1[4], 8
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	cache	r1[0], 0
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	sync	0
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	/* Reset the MMU to default settings */
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	mov	r0, SYSREG_BIT(MMUCR_S) | SYSREG_BIT(MMUCR_I)
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	mtsr	SYSREG_MMUCR, r0
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	/* Internal RAM should not need any initialization.  We might
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	   have to initialize external RAM here if the part doesn't
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	   have internal RAM (or we may use the data cache) */
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	/* Jump to cacheable segment */
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	lddpc	pc, 1f
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	.align	2
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1:	.long	2f
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2:	lddpc	sp, sp_init
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	/* Initialize the GOT pointer */
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	lddpc	r6, got_init
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3:	rsub	r6, pc
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	/* Let's go */
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	rjmp	board_init_f
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	.align	2
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	.type	sp_init,@object
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sp_init:
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	.long	CFG_INIT_SP_ADDR
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got_init:
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	.long	3b - _GLOBAL_OFFSET_TABLE_
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	/*
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	 * void	relocate_code(new_sp, new_gd, monitor_addr)
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	 *
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	 * Relocate the u-boot image into RAM and continue from there.
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	 * Does not return.
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	 */
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	.global	relocate_code
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	.type	relocate_code,@function
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relocate_code:
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	mov	sp, r12		/* use new stack */
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	mov	r12, r11	/* save new_gd */
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	mov	r11, r10	/* save destination address */
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	/* copy .text section and flush the cache along the way */
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	lda.w	r8, _text
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	lda.w	r9, _etext
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	sub	lr, r10, r8	/* relocation offset */
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1:	ldm	r8++, r0-r3
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	stm	r10, r0-r3
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	sub	r10, -16
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	ldm	r8++, r0-r3
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	stm	r10, r0-r3
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	sub	r10, -16
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	cp.w	r8, r9
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	cache	r10[-4], 0x0d	/* dcache clean/invalidate */
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	cache	r10[-4], 0x01	/* icache invalidate */
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	brlt	1b
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	/* flush write buffer */
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	sync	0
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	/* copy data sections */
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	lda.w	r9, _edata
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1:	ld.d	r0, r8++
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	st.d	r10++, r0
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	cp.w	r8, r9
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	brlt	1b
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	/* zero out .bss */
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	mov	r0, 0
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	mov	r1, 0
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	lda.w	r9, _end
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	sub	r9, r8
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1:	st.d	r10++, r0
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	sub	r9, 8
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	brgt	1b
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	/* jump to RAM */
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	sub	r0, pc, . - in_ram
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	add	pc, r0, lr
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	.align	2
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in_ram:
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	/* find the new GOT and relocate it */
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	lddpc	r6, got_init_reloc
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3:	rsub	r6, pc
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	mov	r8, r6
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	lda.w	r9, _egot
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	lda.w	r10, _got
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	sub	r9, r10
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1:	ld.w	r0, r8[0]
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	add	r0, lr
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	st.w	r8++, r0
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	sub	r9, 4
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	brgt	1b
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	/* Move the exception handlers */
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	mfsr	r2, SYSREG_EVBA
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	add	r2, lr
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	mtsr	SYSREG_EVBA, r2
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	/* Do the rest of the initialization sequence */
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	call	board_init_r
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	.align	2
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got_init_reloc:
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	.long	3b - _GLOBAL_OFFSET_TABLE_
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