The CPU reset functions disable the MMU and therefore must be executed with an identity mapping in place. This patch places the CPU reset functions into the .idmap.text section, causing the idmap code to include them as part of the identity mapping. Acked-by: Dave Martin <dave.martin@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
		
			
				
	
	
		
			295 lines
		
	
	
	
		
			8.1 KiB
			
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
			
		
		
	
	
			295 lines
		
	
	
	
		
			8.1 KiB
			
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
/*
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 *  linux/arch/arm/mm/proc-v6.S
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 *
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 *  Copyright (C) 2001 Deep Blue Solutions Ltd.
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 *  Modified by Catalin Marinas for noMMU support
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 *
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 * This program is free software; you can redistribute it and/or modify
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 * it under the terms of the GNU General Public License version 2 as
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 * published by the Free Software Foundation.
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 *
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 *  This is the "shell" of the ARMv6 processor support.
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 */
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#include <linux/init.h>
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#include <linux/linkage.h>
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#include <asm/assembler.h>
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#include <asm/asm-offsets.h>
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#include <asm/hwcap.h>
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#include <asm/pgtable-hwdef.h>
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#include <asm/pgtable.h>
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#include "proc-macros.S"
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#define D_CACHE_LINE_SIZE	32
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#define TTB_C		(1 << 0)
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#define TTB_S		(1 << 1)
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#define TTB_IMP		(1 << 2)
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#define TTB_RGN_NC	(0 << 3)
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#define TTB_RGN_WBWA	(1 << 3)
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#define TTB_RGN_WT	(2 << 3)
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#define TTB_RGN_WB	(3 << 3)
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#define TTB_FLAGS_UP	TTB_RGN_WBWA
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#define PMD_FLAGS_UP	PMD_SECT_WB
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#define TTB_FLAGS_SMP	TTB_RGN_WBWA|TTB_S
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#define PMD_FLAGS_SMP	PMD_SECT_WBWA|PMD_SECT_S
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ENTRY(cpu_v6_proc_init)
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	mov	pc, lr
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ENTRY(cpu_v6_proc_fin)
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	mrc	p15, 0, r0, c1, c0, 0		@ ctrl register
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	bic	r0, r0, #0x1000			@ ...i............
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	bic	r0, r0, #0x0006			@ .............ca.
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	mcr	p15, 0, r0, c1, c0, 0		@ disable caches
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	mov	pc, lr
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/*
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 *	cpu_v6_reset(loc)
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 *
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 *	Perform a soft reset of the system.  Put the CPU into the
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 *	same state as it would be if it had been reset, and branch
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 *	to what would be the reset vector.
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 *
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 *	- loc   - location to jump to for soft reset
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 */
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	.align	5
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	.pushsection	.idmap.text, "ax"
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ENTRY(cpu_v6_reset)
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	mrc	p15, 0, r1, c1, c0, 0		@ ctrl register
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	bic	r1, r1, #0x1			@ ...............m
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	mcr	p15, 0, r1, c1, c0, 0		@ disable MMU
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	mov	r1, #0
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	mcr	p15, 0, r1, c7, c5, 4		@ ISB
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	mov	pc, r0
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ENDPROC(cpu_v6_reset)
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	.popsection
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/*
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 *	cpu_v6_do_idle()
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 *
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 *	Idle the processor (eg, wait for interrupt).
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 *
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 *	IRQs are already disabled.
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 */
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ENTRY(cpu_v6_do_idle)
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	mov	r1, #0
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	mcr	p15, 0, r1, c7, c10, 4		@ DWB - WFI may enter a low-power mode
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	mcr	p15, 0, r1, c7, c0, 4		@ wait for interrupt
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	mov	pc, lr
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ENTRY(cpu_v6_dcache_clean_area)
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#ifndef TLB_CAN_READ_FROM_L1_CACHE
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1:	mcr	p15, 0, r0, c7, c10, 1		@ clean D entry
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	add	r0, r0, #D_CACHE_LINE_SIZE
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	subs	r1, r1, #D_CACHE_LINE_SIZE
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	bhi	1b
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#endif
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	mov	pc, lr
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/*
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 *	cpu_arm926_switch_mm(pgd_phys, tsk)
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 *
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 *	Set the translation table base pointer to be pgd_phys
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 *
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 *	- pgd_phys - physical address of new TTB
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 *
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 *	It is assumed that:
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 *	- we are not using split page tables
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 */
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ENTRY(cpu_v6_switch_mm)
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#ifdef CONFIG_MMU
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	mov	r2, #0
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	ldr	r1, [r1, #MM_CONTEXT_ID]	@ get mm->context.id
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	ALT_SMP(orr	r0, r0, #TTB_FLAGS_SMP)
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	ALT_UP(orr	r0, r0, #TTB_FLAGS_UP)
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	mcr	p15, 0, r2, c7, c5, 6		@ flush BTAC/BTB
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	mcr	p15, 0, r2, c7, c10, 4		@ drain write buffer
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	mcr	p15, 0, r0, c2, c0, 0		@ set TTB 0
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	mcr	p15, 0, r1, c13, c0, 1		@ set context ID
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#endif
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	mov	pc, lr
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/*
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 *	cpu_v6_set_pte_ext(ptep, pte, ext)
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 *
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 *	Set a level 2 translation table entry.
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 *
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 *	- ptep  - pointer to level 2 translation table entry
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 *		  (hardware version is stored at -1024 bytes)
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 *	- pte   - PTE value to store
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 *	- ext	- value for extended PTE bits
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 */
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	armv6_mt_table cpu_v6
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ENTRY(cpu_v6_set_pte_ext)
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#ifdef CONFIG_MMU
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	armv6_set_pte_ext cpu_v6
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#endif
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	mov	pc, lr
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/* Suspend/resume support: taken from arch/arm/mach-s3c64xx/sleep.S */
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.globl	cpu_v6_suspend_size
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.equ	cpu_v6_suspend_size, 4 * 6
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#ifdef CONFIG_PM_SLEEP
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ENTRY(cpu_v6_do_suspend)
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	stmfd	sp!, {r4 - r9, lr}
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	mrc	p15, 0, r4, c13, c0, 0	@ FCSE/PID
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	mrc	p15, 0, r5, c3, c0, 0	@ Domain ID
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	mrc	p15, 0, r6, c2, c0, 1	@ Translation table base 1
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	mrc	p15, 0, r7, c1, c0, 1	@ auxiliary control register
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	mrc	p15, 0, r8, c1, c0, 2	@ co-processor access control
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	mrc	p15, 0, r9, c1, c0, 0	@ control register
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	stmia	r0, {r4 - r9}
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	ldmfd	sp!, {r4- r9, pc}
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ENDPROC(cpu_v6_do_suspend)
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ENTRY(cpu_v6_do_resume)
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	mov	ip, #0
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	mcr	p15, 0, ip, c7, c14, 0	@ clean+invalidate D cache
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	mcr	p15, 0, ip, c7, c5, 0	@ invalidate I cache
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	mcr	p15, 0, ip, c7, c15, 0	@ clean+invalidate cache
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	mcr	p15, 0, ip, c7, c10, 4	@ drain write buffer
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	mcr	p15, 0, ip, c13, c0, 1	@ set reserved context ID
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	ldmia	r0, {r4 - r9}
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	mcr	p15, 0, r4, c13, c0, 0	@ FCSE/PID
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	mcr	p15, 0, r5, c3, c0, 0	@ Domain ID
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	ALT_SMP(orr	r1, r1, #TTB_FLAGS_SMP)
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	ALT_UP(orr	r1, r1, #TTB_FLAGS_UP)
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	mcr	p15, 0, r1, c2, c0, 0	@ Translation table base 0
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	mcr	p15, 0, r6, c2, c0, 1	@ Translation table base 1
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	mcr	p15, 0, r7, c1, c0, 1	@ auxiliary control register
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	mcr	p15, 0, r8, c1, c0, 2	@ co-processor access control
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	mcr	p15, 0, ip, c2, c0, 2	@ TTB control register
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	mcr	p15, 0, ip, c7, c5, 4	@ ISB
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	mov	r0, r9			@ control register
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	b	cpu_resume_mmu
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ENDPROC(cpu_v6_do_resume)
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#endif
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	string	cpu_v6_name, "ARMv6-compatible processor"
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	.align
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	__CPUINIT
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/*
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 *	__v6_setup
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 *
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 *	Initialise TLB, Caches, and MMU state ready to switch the MMU
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 *	on.  Return in r0 the new CP15 C1 control register setting.
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 *
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 *	We automatically detect if we have a Harvard cache, and use the
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 *	Harvard cache control instructions insead of the unified cache
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 *	control instructions.
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 *
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 *	This should be able to cover all ARMv6 cores.
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 *
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 *	It is assumed that:
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 *	- cache type register is implemented
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 */
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__v6_setup:
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#ifdef CONFIG_SMP
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	ALT_SMP(mrc	p15, 0, r0, c1, c0, 1)	@ Enable SMP/nAMP mode
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	ALT_UP(nop)
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	orr	r0, r0, #0x20
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	ALT_SMP(mcr	p15, 0, r0, c1, c0, 1)
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	ALT_UP(nop)
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#endif
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	mov	r0, #0
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	mcr	p15, 0, r0, c7, c14, 0		@ clean+invalidate D cache
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	mcr	p15, 0, r0, c7, c5, 0		@ invalidate I cache
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	mcr	p15, 0, r0, c7, c15, 0		@ clean+invalidate cache
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	mcr	p15, 0, r0, c7, c10, 4		@ drain write buffer
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#ifdef CONFIG_MMU
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	mcr	p15, 0, r0, c8, c7, 0		@ invalidate I + D TLBs
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	mcr	p15, 0, r0, c2, c0, 2		@ TTB control register
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	ALT_SMP(orr	r4, r4, #TTB_FLAGS_SMP)
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	ALT_UP(orr	r4, r4, #TTB_FLAGS_UP)
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	ALT_SMP(orr	r8, r8, #TTB_FLAGS_SMP)
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	ALT_UP(orr	r8, r8, #TTB_FLAGS_UP)
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	mcr	p15, 0, r8, c2, c0, 1		@ load TTB1
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#endif /* CONFIG_MMU */
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	adr	r5, v6_crval
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	ldmia	r5, {r5, r6}
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#ifdef CONFIG_CPU_ENDIAN_BE8
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	orr	r6, r6, #1 << 25		@ big-endian page tables
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#endif
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	mrc	p15, 0, r0, c1, c0, 0		@ read control register
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	bic	r0, r0, r5			@ clear bits them
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	orr	r0, r0, r6			@ set them
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#ifdef CONFIG_ARM_ERRATA_364296
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	/*
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	 * Workaround for the 364296 ARM1136 r0p2 erratum (possible cache data
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	 * corruption with hit-under-miss enabled). The conditional code below
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	 * (setting the undocumented bit 31 in the auxiliary control register
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	 * and the FI bit in the control register) disables hit-under-miss
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	 * without putting the processor into full low interrupt latency mode.
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	 */
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	ldr	r6, =0x4107b362			@ id for ARM1136 r0p2
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	mrc	p15, 0, r5, c0, c0, 0		@ get processor id
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	teq	r5, r6				@ check for the faulty core
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	mrceq	p15, 0, r5, c1, c0, 1		@ load aux control reg
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	orreq	r5, r5, #(1 << 31)		@ set the undocumented bit 31
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	mcreq	p15, 0, r5, c1, c0, 1		@ write aux control reg
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	orreq	r0, r0, #(1 << 21)		@ low interrupt latency configuration
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#endif
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	mov	pc, lr				@ return to head.S:__ret
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	/*
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	 *         V X F   I D LR
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	 * .... ...E PUI. .T.T 4RVI ZFRS BLDP WCAM
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	 * rrrr rrrx xxx0 0101 xxxx xxxx x111 xxxx < forced
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	 *         0 110       0011 1.00 .111 1101 < we want
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	 */
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	.type	v6_crval, #object
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v6_crval:
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	crval	clear=0x01e0fb7f, mmuset=0x00c0387d, ucset=0x00c0187c
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	__INITDATA
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	@ define struct processor (see <asm/proc-fns.h> and proc-macros.S)
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	define_processor_functions v6, dabort=v6_early_abort, pabort=v6_pabort, suspend=1
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	.section ".rodata"
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	string	cpu_arch_name, "armv6"
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	string	cpu_elf_name, "v6"
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	.align
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	.section ".proc.info.init", #alloc, #execinstr
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	/*
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	 * Match any ARMv6 processor core.
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	 */
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	.type	__v6_proc_info, #object
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__v6_proc_info:
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	.long	0x0007b000
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	.long	0x0007f000
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	ALT_SMP(.long \
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		PMD_TYPE_SECT | \
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		PMD_SECT_AP_WRITE | \
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		PMD_SECT_AP_READ | \
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		PMD_FLAGS_SMP)
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	ALT_UP(.long \
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		PMD_TYPE_SECT | \
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		PMD_SECT_AP_WRITE | \
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		PMD_SECT_AP_READ | \
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		PMD_FLAGS_UP)
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	.long   PMD_TYPE_SECT | \
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		PMD_SECT_XN | \
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		PMD_SECT_AP_WRITE | \
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		PMD_SECT_AP_READ
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	b	__v6_setup
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	.long	cpu_arch_name
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	.long	cpu_elf_name
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	/* See also feat_v6_fixup() for HWCAP_TLS */
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	.long	HWCAP_SWP|HWCAP_HALF|HWCAP_THUMB|HWCAP_FAST_MULT|HWCAP_EDSP|HWCAP_JAVA|HWCAP_TLS
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	.long	cpu_v6_name
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	.long	v6_processor_functions
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	.long	v6wbi_tlb_fns
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	.long	v6_user_fns
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	.long	v6_cache_fns
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	.size	__v6_proc_info, . - __v6_proc_info
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