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		3ea128065e
		
	
	
	
	
		
			
			On ARMv7, the memory barrier instructions take an optional `option' field which can be used to constrain the effects of a memory barrier based on shareability and access type. This patch allows the caller to pass these options if required, and updates the smp_*() barriers to request inner-shareable barriers, affecting only stores for the _wmb variant. wmb() is also changed to use the -st version of dsb. Reported-by: Albin Tonnerre <albin.tonnerre@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
		
			
				
	
	
		
			69 lines
		
	
	
		
			2.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			69 lines
		
	
	
		
			2.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| #ifndef __ASM_BARRIER_H
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| #define __ASM_BARRIER_H
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| 
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| #ifndef __ASSEMBLY__
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| #include <asm/outercache.h>
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| 
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| #define nop() __asm__ __volatile__("mov\tr0,r0\t@ nop\n\t");
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| 
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| #if __LINUX_ARM_ARCH__ >= 7 ||		\
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| 	(__LINUX_ARM_ARCH__ == 6 && defined(CONFIG_CPU_32v6K))
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| #define sev()	__asm__ __volatile__ ("sev" : : : "memory")
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| #define wfe()	__asm__ __volatile__ ("wfe" : : : "memory")
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| #define wfi()	__asm__ __volatile__ ("wfi" : : : "memory")
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| #endif
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| 
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| #if __LINUX_ARM_ARCH__ >= 7
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| #define isb(option) __asm__ __volatile__ ("isb " #option : : : "memory")
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| #define dsb(option) __asm__ __volatile__ ("dsb " #option : : : "memory")
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| #define dmb(option) __asm__ __volatile__ ("dmb " #option : : : "memory")
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| #elif defined(CONFIG_CPU_XSC3) || __LINUX_ARM_ARCH__ == 6
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| #define isb(x) __asm__ __volatile__ ("mcr p15, 0, %0, c7, c5, 4" \
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| 				    : : "r" (0) : "memory")
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| #define dsb(x) __asm__ __volatile__ ("mcr p15, 0, %0, c7, c10, 4" \
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| 				    : : "r" (0) : "memory")
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| #define dmb(x) __asm__ __volatile__ ("mcr p15, 0, %0, c7, c10, 5" \
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| 				    : : "r" (0) : "memory")
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| #elif defined(CONFIG_CPU_FA526)
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| #define isb(x) __asm__ __volatile__ ("mcr p15, 0, %0, c7, c5, 4" \
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| 				    : : "r" (0) : "memory")
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| #define dsb(x) __asm__ __volatile__ ("mcr p15, 0, %0, c7, c10, 4" \
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| 				    : : "r" (0) : "memory")
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| #define dmb(x) __asm__ __volatile__ ("" : : : "memory")
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| #else
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| #define isb(x) __asm__ __volatile__ ("" : : : "memory")
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| #define dsb(x) __asm__ __volatile__ ("mcr p15, 0, %0, c7, c10, 4" \
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| 				    : : "r" (0) : "memory")
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| #define dmb(x) __asm__ __volatile__ ("" : : : "memory")
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| #endif
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| 
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| #ifdef CONFIG_ARCH_HAS_BARRIERS
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| #include <mach/barriers.h>
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| #elif defined(CONFIG_ARM_DMA_MEM_BUFFERABLE) || defined(CONFIG_SMP)
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| #define mb()		do { dsb(); outer_sync(); } while (0)
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| #define rmb()		dsb()
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| #define wmb()		do { dsb(st); outer_sync(); } while (0)
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| #else
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| #define mb()		barrier()
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| #define rmb()		barrier()
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| #define wmb()		barrier()
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| #endif
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| 
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| #ifndef CONFIG_SMP
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| #define smp_mb()	barrier()
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| #define smp_rmb()	barrier()
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| #define smp_wmb()	barrier()
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| #else
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| #define smp_mb()	dmb(ish)
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| #define smp_rmb()	smp_mb()
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| #define smp_wmb()	dmb(ishst)
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| #endif
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| 
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| #define read_barrier_depends()		do { } while(0)
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| #define smp_read_barrier_depends()	do { } while(0)
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| 
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| #define set_mb(var, value)	do { var = value; smp_mb(); } while (0)
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| 
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| #endif /* !__ASSEMBLY__ */
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| #endif /* __ASM_BARRIER_H */
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