 3e0a07f8c4
			
		
	
	
	3e0a07f8c4
	
	
	
		
			
			This commit fixes the regression on Armada 370 (the kernal hang during boot) introduced by the commit: "ARM: 7691/1: mm: kill unused TLB_CAN_READ_FROM_L1_CACHE and use ALT_SMP instead". When coming out of either a Wait for Interrupt (WFI) or a Wait for Event (WFE) IDLE states, a specific timing sensitivity exists between the retiring WFI/WFE instructions and the newly issued subsequent instructions. This sensitivity can result in a CPU hang scenario. The workaround is to insert either a Data Synchronization Barrier (DSB) or Data Memory Barrier (DMB) command immediately after the WFI/WFE instruction. This commit was based on the work of Lior Amsalem, but heavily modified to apply the errata fix dynamically according to the processor type thanks to the suggestions of Russell King and Nicolas Pitre. Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com> Reviewed-by: Will Deacon <will.deacon@arm.com> Acked-by: Nicolas Pitre <nico@linaro.org> Tested-by: Willy Tarreau <w@1wt.eu> Cc: <stable@vger.kernel.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
		
			
				
	
	
		
			340 lines
		
	
	
	
		
			7.9 KiB
			
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
			
		
		
	
	
			340 lines
		
	
	
	
		
			7.9 KiB
			
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
| /*
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|  * We need constants.h for:
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|  *  VMA_VM_MM
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|  *  VMA_VM_FLAGS
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|  *  VM_EXEC
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|  */
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| #include <asm/asm-offsets.h>
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| #include <asm/thread_info.h>
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| 
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| /*
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|  * vma_vm_mm - get mm pointer from vma pointer (vma->vm_mm)
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|  */
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| 	.macro	vma_vm_mm, rd, rn
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| 	ldr	\rd, [\rn, #VMA_VM_MM]
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| 	.endm
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| 
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| /*
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|  * vma_vm_flags - get vma->vm_flags
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|  */
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| 	.macro	vma_vm_flags, rd, rn
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| 	ldr	\rd, [\rn, #VMA_VM_FLAGS]
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| 	.endm
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| 
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| 	.macro	tsk_mm, rd, rn
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| 	ldr	\rd, [\rn, #TI_TASK]
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| 	ldr	\rd, [\rd, #TSK_ACTIVE_MM]
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| 	.endm
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| 
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| /*
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|  * act_mm - get current->active_mm
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|  */
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| 	.macro	act_mm, rd
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| 	bic	\rd, sp, #8128
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| 	bic	\rd, \rd, #63
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| 	ldr	\rd, [\rd, #TI_TASK]
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| 	ldr	\rd, [\rd, #TSK_ACTIVE_MM]
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| 	.endm
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| 
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| /*
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|  * mmid - get context id from mm pointer (mm->context.id)
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|  * note, this field is 64bit, so in big-endian the two words are swapped too.
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|  */
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| 	.macro	mmid, rd, rn
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| #ifdef __ARMEB__
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| 	ldr	\rd, [\rn, #MM_CONTEXT_ID + 4 ]
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| #else
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| 	ldr	\rd, [\rn, #MM_CONTEXT_ID]
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| #endif
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| 	.endm
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| 
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| /*
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|  * mask_asid - mask the ASID from the context ID
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|  */
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| 	.macro	asid, rd, rn
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| 	and	\rd, \rn, #255
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| 	.endm
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| 
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| 	.macro	crval, clear, mmuset, ucset
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| #ifdef CONFIG_MMU
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| 	.word	\clear
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| 	.word	\mmuset
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| #else
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| 	.word	\clear
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| 	.word	\ucset
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| #endif
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| 	.endm
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| 
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| /*
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|  * dcache_line_size - get the minimum D-cache line size from the CTR register
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|  * on ARMv7.
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|  */
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| 	.macro	dcache_line_size, reg, tmp
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| 	mrc	p15, 0, \tmp, c0, c0, 1		@ read ctr
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| 	lsr	\tmp, \tmp, #16
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| 	and	\tmp, \tmp, #0xf		@ cache line size encoding
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| 	mov	\reg, #4			@ bytes per word
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| 	mov	\reg, \reg, lsl \tmp		@ actual cache line size
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| 	.endm
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| 
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| /*
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|  * icache_line_size - get the minimum I-cache line size from the CTR register
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|  * on ARMv7.
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|  */
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| 	.macro	icache_line_size, reg, tmp
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| 	mrc	p15, 0, \tmp, c0, c0, 1		@ read ctr
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| 	and	\tmp, \tmp, #0xf		@ cache line size encoding
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| 	mov	\reg, #4			@ bytes per word
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| 	mov	\reg, \reg, lsl \tmp		@ actual cache line size
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| 	.endm
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| 
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| /*
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|  * Sanity check the PTE configuration for the code below - which makes
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|  * certain assumptions about how these bits are laid out.
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|  */
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| #ifdef CONFIG_MMU
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| #if L_PTE_SHARED != PTE_EXT_SHARED
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| #error PTE shared bit mismatch
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| #endif
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| #if !defined (CONFIG_ARM_LPAE) && \
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| 	(L_PTE_XN+L_PTE_USER+L_PTE_RDONLY+L_PTE_DIRTY+L_PTE_YOUNG+\
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| 	 L_PTE_FILE+L_PTE_PRESENT) > L_PTE_SHARED
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| #error Invalid Linux PTE bit settings
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| #endif
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| #endif	/* CONFIG_MMU */
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| 
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| /*
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|  * The ARMv6 and ARMv7 set_pte_ext translation function.
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|  *
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|  * Permission translation:
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|  *  YUWD  APX AP1 AP0	SVC	User
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|  *  0xxx   0   0   0	no acc	no acc
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|  *  100x   1   0   1	r/o	no acc
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|  *  10x0   1   0   1	r/o	no acc
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|  *  1011   0   0   1	r/w	no acc
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|  *  110x   0   1   0	r/w	r/o
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|  *  11x0   0   1   0	r/w	r/o
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|  *  1111   0   1   1	r/w	r/w
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|  *
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|  * If !CONFIG_CPU_USE_DOMAINS, the following permissions are changed:
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|  *  110x   1   1   1	r/o	r/o
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|  *  11x0   1   1   1	r/o	r/o
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|  */
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| 	.macro	armv6_mt_table pfx
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| \pfx\()_mt_table:
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| 	.long	0x00						@ L_PTE_MT_UNCACHED
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| 	.long	PTE_EXT_TEX(1)					@ L_PTE_MT_BUFFERABLE
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| 	.long	PTE_CACHEABLE					@ L_PTE_MT_WRITETHROUGH
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| 	.long	PTE_CACHEABLE | PTE_BUFFERABLE			@ L_PTE_MT_WRITEBACK
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| 	.long	PTE_BUFFERABLE					@ L_PTE_MT_DEV_SHARED
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| 	.long	0x00						@ unused
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| 	.long	0x00						@ L_PTE_MT_MINICACHE (not present)
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| 	.long	PTE_EXT_TEX(1) | PTE_CACHEABLE | PTE_BUFFERABLE	@ L_PTE_MT_WRITEALLOC
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| 	.long	0x00						@ unused
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| 	.long	PTE_EXT_TEX(1)					@ L_PTE_MT_DEV_WC
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| 	.long	0x00						@ unused
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| 	.long	PTE_CACHEABLE | PTE_BUFFERABLE			@ L_PTE_MT_DEV_CACHED
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| 	.long	PTE_EXT_TEX(2)					@ L_PTE_MT_DEV_NONSHARED
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| 	.long	0x00						@ unused
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| 	.long	0x00						@ unused
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| 	.long	0x00						@ unused
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| 	.endm
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| 
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| 	.macro	armv6_set_pte_ext pfx
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| 	str	r1, [r0], #2048			@ linux version
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| 
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| 	bic	r3, r1, #0x000003fc
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| 	bic	r3, r3, #PTE_TYPE_MASK
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| 	orr	r3, r3, r2
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| 	orr	r3, r3, #PTE_EXT_AP0 | 2
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| 
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| 	adr	ip, \pfx\()_mt_table
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| 	and	r2, r1, #L_PTE_MT_MASK
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| 	ldr	r2, [ip, r2]
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| 
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| 	eor	r1, r1, #L_PTE_DIRTY
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| 	tst	r1, #L_PTE_DIRTY|L_PTE_RDONLY
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| 	orrne	r3, r3, #PTE_EXT_APX
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| 
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| 	tst	r1, #L_PTE_USER
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| 	orrne	r3, r3, #PTE_EXT_AP1
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| #ifdef CONFIG_CPU_USE_DOMAINS
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| 	@ allow kernel read/write access to read-only user pages
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| 	tstne	r3, #PTE_EXT_APX
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| 	bicne	r3, r3, #PTE_EXT_APX | PTE_EXT_AP0
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| #endif
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| 
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| 	tst	r1, #L_PTE_XN
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| 	orrne	r3, r3, #PTE_EXT_XN
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| 
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| 	orr	r3, r3, r2
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| 
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| 	tst	r1, #L_PTE_YOUNG
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| 	tstne	r1, #L_PTE_PRESENT
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| 	moveq	r3, #0
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| #ifndef CONFIG_CPU_USE_DOMAINS
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| 	tstne	r1, #L_PTE_NONE
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| 	movne	r3, #0
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| #endif
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| 
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| 	str	r3, [r0]
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| 	mcr	p15, 0, r0, c7, c10, 1		@ flush_pte
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| 	.endm
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| 
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| 
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| /*
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|  * The ARMv3, ARMv4 and ARMv5 set_pte_ext translation function,
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|  * covering most CPUs except Xscale and Xscale 3.
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|  *
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|  * Permission translation:
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|  *  YUWD   AP	SVC	User
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|  *  0xxx  0x00	no acc	no acc
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|  *  100x  0x00	r/o	no acc
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|  *  10x0  0x00	r/o	no acc
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|  *  1011  0x55	r/w	no acc
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|  *  110x  0xaa	r/w	r/o
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|  *  11x0  0xaa	r/w	r/o
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|  *  1111  0xff	r/w	r/w
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|  */
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| 	.macro	armv3_set_pte_ext wc_disable=1
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| 	str	r1, [r0], #2048			@ linux version
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| 
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| 	eor	r3, r1, #L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY
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| 
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| 	bic	r2, r1, #PTE_SMALL_AP_MASK	@ keep C, B bits
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| 	bic	r2, r2, #PTE_TYPE_MASK
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| 	orr	r2, r2, #PTE_TYPE_SMALL
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| 
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| 	tst	r3, #L_PTE_USER			@ user?
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| 	orrne	r2, r2, #PTE_SMALL_AP_URO_SRW
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| 
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| 	tst	r3, #L_PTE_RDONLY | L_PTE_DIRTY	@ write and dirty?
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| 	orreq	r2, r2, #PTE_SMALL_AP_UNO_SRW
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| 
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| 	tst	r3, #L_PTE_PRESENT | L_PTE_YOUNG	@ present and young?
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| 	movne	r2, #0
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| 
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| 	.if	\wc_disable
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| #ifdef CONFIG_CPU_DCACHE_WRITETHROUGH
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| 	tst	r2, #PTE_CACHEABLE
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| 	bicne	r2, r2, #PTE_BUFFERABLE
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| #endif
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| 	.endif
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| 	str	r2, [r0]		@ hardware version
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| 	.endm
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| 
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| 
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| /*
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|  * Xscale set_pte_ext translation, split into two halves to cope
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|  * with work-arounds.  r3 must be preserved by code between these
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|  * two macros.
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|  *
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|  * Permission translation:
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|  *  YUWD  AP	SVC	User
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|  *  0xxx  00	no acc	no acc
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|  *  100x  00	r/o	no acc
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|  *  10x0  00	r/o	no acc
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|  *  1011  01	r/w	no acc
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|  *  110x  10	r/w	r/o
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|  *  11x0  10	r/w	r/o
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|  *  1111  11	r/w	r/w
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|  */
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| 	.macro	xscale_set_pte_ext_prologue
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| 	str	r1, [r0]			@ linux version
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| 
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| 	eor	r3, r1, #L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY
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| 
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| 	bic	r2, r1, #PTE_SMALL_AP_MASK	@ keep C, B bits
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| 	orr	r2, r2, #PTE_TYPE_EXT		@ extended page
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| 
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| 	tst	r3, #L_PTE_USER			@ user?
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| 	orrne	r2, r2, #PTE_EXT_AP_URO_SRW	@ yes -> user r/o, system r/w
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| 
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| 	tst	r3, #L_PTE_RDONLY | L_PTE_DIRTY	@ write and dirty?
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| 	orreq	r2, r2, #PTE_EXT_AP_UNO_SRW	@ yes -> user n/a, system r/w
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| 						@ combined with user -> user r/w
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| 	.endm
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| 
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| 	.macro	xscale_set_pte_ext_epilogue
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| 	tst	r3, #L_PTE_PRESENT | L_PTE_YOUNG	@ present and young?
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| 	movne	r2, #0				@ no -> fault
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| 
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| 	str	r2, [r0, #2048]!		@ hardware version
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| 	mov	ip, #0
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| 	mcr	p15, 0, r0, c7, c10, 1		@ clean L1 D line
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| 	mcr	p15, 0, ip, c7, c10, 4		@ data write barrier
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| 	.endm
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| 
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| .macro define_processor_functions name:req, dabort:req, pabort:req, nommu=0, suspend=0
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| 	.type	\name\()_processor_functions, #object
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| 	.align 2
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| ENTRY(\name\()_processor_functions)
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| 	.word	\dabort
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| 	.word	\pabort
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| 	.word	cpu_\name\()_proc_init
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| 	.word	cpu_\name\()_proc_fin
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| 	.word	cpu_\name\()_reset
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| 	.word	cpu_\name\()_do_idle
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| 	.word	cpu_\name\()_dcache_clean_area
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| 	.word	cpu_\name\()_switch_mm
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| 
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| 	.if \nommu
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| 	.word	0
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| 	.else
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| 	.word	cpu_\name\()_set_pte_ext
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| 	.endif
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| 
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| 	.if \suspend
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| 	.word	cpu_\name\()_suspend_size
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| #ifdef CONFIG_PM_SLEEP
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| 	.word	cpu_\name\()_do_suspend
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| 	.word	cpu_\name\()_do_resume
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| #else
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| 	.word	0
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| 	.word	0
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| #endif
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| 	.else
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| 	.word	0
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| 	.word	0
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| 	.word	0
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| 	.endif
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| 
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| 	.size	\name\()_processor_functions, . - \name\()_processor_functions
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| .endm
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| 
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| .macro define_cache_functions name:req
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| 	.align 2
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| 	.type	\name\()_cache_fns, #object
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| ENTRY(\name\()_cache_fns)
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| 	.long	\name\()_flush_icache_all
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| 	.long	\name\()_flush_kern_cache_all
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| 	.long   \name\()_flush_kern_cache_louis
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| 	.long	\name\()_flush_user_cache_all
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| 	.long	\name\()_flush_user_cache_range
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| 	.long	\name\()_coherent_kern_range
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| 	.long	\name\()_coherent_user_range
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| 	.long	\name\()_flush_kern_dcache_area
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| 	.long	\name\()_dma_map_area
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| 	.long	\name\()_dma_unmap_area
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| 	.long	\name\()_dma_flush_range
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| 	.size	\name\()_cache_fns, . - \name\()_cache_fns
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| .endm
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| 
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| .macro define_tlb_functions name:req, flags_up:req, flags_smp
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| 	.type	\name\()_tlb_fns, #object
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| ENTRY(\name\()_tlb_fns)
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| 	.long	\name\()_flush_user_tlb_range
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| 	.long	\name\()_flush_kern_tlb_range
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| 	.ifnb \flags_smp
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| 		ALT_SMP(.long	\flags_smp )
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| 		ALT_UP(.long	\flags_up )
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| 	.else
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| 		.long	\flags_up
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| 	.endif
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| 	.size	\name\()_tlb_fns, . - \name\()_tlb_fns
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| .endm
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| 
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| .macro globl_equ x, y
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| 	.globl	\x
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| 	.equ	\x, \y
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| .endm
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