Commit e6a5d66f authored by Catalin Marinas's avatar Catalin Marinas Committed by Russell King
Browse files

[ARM] 4129/1: Add barriers after the TLB operations 



The architecture specification states that TLB operations are
guaranteed to be complete only after the execution of a DSB (Data
Synchronisation Barrier, former Data Write Barrier or Drain Write
Buffer). The branch target cache invalidation is also needed. The ISB
(Instruction Synchronisation Barrier, formerly Prefetch Flush) is
needed unless there will be a return from exception before the
corresponding mapping is used (i.e. user mappings).

Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
parent 9d99df4b

arch/arm/mm/tlb-v6.S

+4 −0
Original line number Diff line number Diff line
@@ -53,6 +53,8 @@ ENTRY(v6wbi_flush_user_tlb_range) 
	add	r0, r0, #PAGE_SZ

	cmp	r0, r1

	blo	1b

	mcr	p15, 0, ip, c7, c5, 6		@ flush BTAC/BTB

	mcr	p15, 0, ip, c7, c10, 4		@ data synchronization barrier

	mov	pc, lr



/*
@@ -80,7 +82,9 @@ ENTRY(v6wbi_flush_kern_tlb_range) 
	add	r0, r0, #PAGE_SZ

	cmp	r0, r1

	blo	1b

	mcr	p15, 0, r2, c7, c5, 6		@ flush BTAC/BTB

	mcr	p15, 0, r2, c7, c10, 4		@ data synchronization barrier

	mcr	p15, 0, r2, c7, c5, 4		@ prefetch flush

	mov	pc, lr



	.section ".text.init", #alloc, #execinstr

include/asm-arm/tlbflush.h

+38 −12
Original line number Diff line number Diff line
@@ -247,7 +247,7 @@ static inline void local_flush_tlb_all(void) 
	const unsigned int __tlb_flag = __cpu_tlb_flags;



	if (tlb_flag(TLB_WB))

		asm("mcr p15, 0, %0, c7, c10, 4" : : "r" (zero) : "cc");

		dsb();



	if (tlb_flag(TLB_V3_FULL))

		asm("mcr p15, 0, %0, c6, c0, 0" : : "r" (zero) : "cc");
@@ -257,6 +257,15 @@ static inline void local_flush_tlb_all(void) 
		asm("mcr p15, 0, %0, c8, c6, 0" : : "r" (zero) : "cc");

	if (tlb_flag(TLB_V4_I_FULL | TLB_V6_I_FULL))

		asm("mcr p15, 0, %0, c8, c5, 0" : : "r" (zero) : "cc");



	if (tlb_flag(TLB_V6_I_FULL | TLB_V6_D_FULL |

		     TLB_V6_I_PAGE | TLB_V6_D_PAGE |

		     TLB_V6_I_ASID | TLB_V6_D_ASID)) {

		/* flush the branch target cache */

		asm("mcr p15, 0, %0, c7, c5, 6" : : "r" (zero) : "cc");

		dsb();

		isb();

	}

}



static inline void local_flush_tlb_mm(struct mm_struct *mm)
@@ -266,7 +275,7 @@ static inline void local_flush_tlb_mm(struct mm_struct *mm) 
	const unsigned int __tlb_flag = __cpu_tlb_flags;



	if (tlb_flag(TLB_WB))

		asm("mcr p15, 0, %0, c7, c10, 4" : : "r" (zero) : "cc");

		dsb();



	if (cpu_isset(smp_processor_id(), mm->cpu_vm_mask)) {

		if (tlb_flag(TLB_V3_FULL))
@@ -285,6 +294,14 @@ static inline void local_flush_tlb_mm(struct mm_struct *mm) 
		asm("mcr p15, 0, %0, c8, c6, 2" : : "r" (asid) : "cc");

	if (tlb_flag(TLB_V6_I_ASID))

		asm("mcr p15, 0, %0, c8, c5, 2" : : "r" (asid) : "cc");



	if (tlb_flag(TLB_V6_I_FULL | TLB_V6_D_FULL |

		     TLB_V6_I_PAGE | TLB_V6_D_PAGE |

		     TLB_V6_I_ASID | TLB_V6_D_ASID)) {

		/* flush the branch target cache */

		asm("mcr p15, 0, %0, c7, c5, 6" : : "r" (zero) : "cc");

		dsb();

	}

}



static inline void
@@ -296,7 +313,7 @@ local_flush_tlb_page(struct vm_area_struct *vma, unsigned long uaddr) 
	uaddr = (uaddr & PAGE_MASK) | ASID(vma->vm_mm);



	if (tlb_flag(TLB_WB))

		asm("mcr p15, 0, %0, c7, c10, 4" : : "r" (zero));

		dsb();



	if (cpu_isset(smp_processor_id(), vma->vm_mm->cpu_vm_mask)) {

		if (tlb_flag(TLB_V3_PAGE))
@@ -317,6 +334,14 @@ local_flush_tlb_page(struct vm_area_struct *vma, unsigned long uaddr) 
		asm("mcr p15, 0, %0, c8, c6, 1" : : "r" (uaddr) : "cc");

	if (tlb_flag(TLB_V6_I_PAGE))

		asm("mcr p15, 0, %0, c8, c5, 1" : : "r" (uaddr) : "cc");



	if (tlb_flag(TLB_V6_I_FULL | TLB_V6_D_FULL |

		     TLB_V6_I_PAGE | TLB_V6_D_PAGE |

		     TLB_V6_I_ASID | TLB_V6_D_ASID)) {

		/* flush the branch target cache */

		asm("mcr p15, 0, %0, c7, c5, 6" : : "r" (zero) : "cc");

		dsb();

	}

}



static inline void local_flush_tlb_kernel_page(unsigned long kaddr)
@@ -327,7 +352,7 @@ static inline void local_flush_tlb_kernel_page(unsigned long kaddr) 
	kaddr &= PAGE_MASK;



	if (tlb_flag(TLB_WB))

		asm("mcr p15, 0, %0, c7, c10, 4" : : "r" (zero) : "cc");

		dsb();



	if (tlb_flag(TLB_V3_PAGE))

		asm("mcr p15, 0, %0, c6, c0, 0" : : "r" (kaddr) : "cc");
@@ -347,11 +372,14 @@ static inline void local_flush_tlb_kernel_page(unsigned long kaddr) 
	if (tlb_flag(TLB_V6_I_PAGE))

		asm("mcr p15, 0, %0, c8, c5, 1" : : "r" (kaddr) : "cc");



	/* The ARM ARM states that the completion of a TLB maintenance

	 * operation is only guaranteed by a DSB instruction

	 */

	if (tlb_flag(TLB_V6_U_PAGE | TLB_V6_D_PAGE | TLB_V6_I_PAGE))

		asm("mcr p15, 0, %0, c7, c10, 4" : : "r" (zero) : "cc");

	if (tlb_flag(TLB_V6_I_FULL | TLB_V6_D_FULL |

		     TLB_V6_I_PAGE | TLB_V6_D_PAGE |

		     TLB_V6_I_ASID | TLB_V6_D_ASID)) {

		/* flush the branch target cache */

		asm("mcr p15, 0, %0, c7, c5, 6" : : "r" (zero) : "cc");

		dsb();

		isb();

	}

}



/*
@@ -369,15 +397,13 @@ static inline void local_flush_tlb_kernel_page(unsigned long kaddr) 
 */

static inline void flush_pmd_entry(pmd_t *pmd)

{

	const unsigned int zero = 0;

	const unsigned int __tlb_flag = __cpu_tlb_flags;



	if (tlb_flag(TLB_DCLEAN))

		asm("mcr	p15, 0, %0, c7, c10, 1	@ flush_pmd"

			: : "r" (pmd) : "cc");

	if (tlb_flag(TLB_WB))

		asm("mcr	p15, 0, %0, c7, c10, 4	@ flush_pmd"

			: : "r" (zero) : "cc");

		dsb();

}



static inline void clean_pmd_entry(pmd_t *pmd)

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