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		d30e45eeab
		
	
	
	
	
		
			
			This switches the ordering of the Linux vs hardware page tables in each page, thereby eliminating some of the arithmetic in the page table walks. As we now place the Linux page table at the beginning of the page, we can deal with the offset in the pgt by simply masking it away, along with the other control bits. This also makes the arithmetic all be positive, rather than a mixture. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
		
			
				
	
	
		
			240 lines
		
	
	
		
			5.5 KiB
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
			
		
		
	
	
			240 lines
		
	
	
		
			5.5 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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|  */
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| 	.macro	mmid, rd, rn
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| 	ldr	\rd, [\rn, #MM_CONTEXT_ID]
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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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|  * cache_line_size - get the cache line size from the CSIDR register
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|  * (available on ARMv7+). It assumes that the CSSR register was configured
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|  * to access the L1 data cache CSIDR.
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|  */
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| 	.macro	dcache_line_size, reg, tmp
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| 	mrc	p15, 1, \tmp, c0, c0, 0		@ read CSIDR
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| 	and	\tmp, \tmp, #7			@ cache line size encoding
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| 	mov	\reg, #16			@ size offset
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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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| /*
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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 layed 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 (L_PTE_EXEC+L_PTE_USER+L_PTE_WRITE+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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| 	.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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| 	tst	r1, #L_PTE_WRITE
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| 	tstne	r1, #L_PTE_DIRTY
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| 	orreq	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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| 	tstne	r3, #PTE_EXT_APX
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| 	bicne	r3, r3, #PTE_EXT_APX | PTE_EXT_AP0
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| 
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| 	tst	r1, #L_PTE_EXEC
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| 	orreq	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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| 
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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_WRITE | 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_WRITE | 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_WRITE | 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_WRITE | 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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