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authorWill Deacon <will.deacon@arm.com>2013-05-10 19:07:19 +0200
committerWill Deacon <will.deacon@arm.com>2013-08-12 13:25:44 +0200
commit3ea128065ed20d33bd02ff6dab689f88e38000be (patch)
treec32b9ec35578f84705af2339941f41ecdfd4d4e0 /arch/arm
parentARM: tlb: don't perform inner-shareable invalidation for local BP ops (diff)
downloadlinux-3ea128065ed20d33bd02ff6dab689f88e38000be.tar.xz
linux-3ea128065ed20d33bd02ff6dab689f88e38000be.zip
ARM: barrier: allow options to be passed to memory barrier instructions
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>
Diffstat (limited to 'arch/arm')
-rw-r--r--arch/arm/include/asm/assembler.h4
-rw-r--r--arch/arm/include/asm/barrier.h32
2 files changed, 18 insertions, 18 deletions
diff --git a/arch/arm/include/asm/assembler.h b/arch/arm/include/asm/assembler.h
index a5fef710af32..fcc1b5bf6979 100644
--- a/arch/arm/include/asm/assembler.h
+++ b/arch/arm/include/asm/assembler.h
@@ -220,9 +220,9 @@
#ifdef CONFIG_SMP
#if __LINUX_ARM_ARCH__ >= 7
.ifeqs "\mode","arm"
- ALT_SMP(dmb)
+ ALT_SMP(dmb ish)
.else
- ALT_SMP(W(dmb))
+ ALT_SMP(W(dmb) ish)
.endif
#elif __LINUX_ARM_ARCH__ == 6
ALT_SMP(mcr p15, 0, r0, c7, c10, 5) @ dmb
diff --git a/arch/arm/include/asm/barrier.h b/arch/arm/include/asm/barrier.h
index 8dcd9c702d90..60f15e274e6d 100644
--- a/arch/arm/include/asm/barrier.h
+++ b/arch/arm/include/asm/barrier.h
@@ -14,27 +14,27 @@
#endif
#if __LINUX_ARM_ARCH__ >= 7
-#define isb() __asm__ __volatile__ ("isb" : : : "memory")
-#define dsb() __asm__ __volatile__ ("dsb" : : : "memory")
-#define dmb() __asm__ __volatile__ ("dmb" : : : "memory")
+#define isb(option) __asm__ __volatile__ ("isb " #option : : : "memory")
+#define dsb(option) __asm__ __volatile__ ("dsb " #option : : : "memory")
+#define dmb(option) __asm__ __volatile__ ("dmb " #option : : : "memory")
#elif defined(CONFIG_CPU_XSC3) || __LINUX_ARM_ARCH__ == 6
-#define isb() __asm__ __volatile__ ("mcr p15, 0, %0, c7, c5, 4" \
+#define isb(x) __asm__ __volatile__ ("mcr p15, 0, %0, c7, c5, 4" \
: : "r" (0) : "memory")
-#define dsb() __asm__ __volatile__ ("mcr p15, 0, %0, c7, c10, 4" \
+#define dsb(x) __asm__ __volatile__ ("mcr p15, 0, %0, c7, c10, 4" \
: : "r" (0) : "memory")
-#define dmb() __asm__ __volatile__ ("mcr p15, 0, %0, c7, c10, 5" \
+#define dmb(x) __asm__ __volatile__ ("mcr p15, 0, %0, c7, c10, 5" \
: : "r" (0) : "memory")
#elif defined(CONFIG_CPU_FA526)
-#define isb() __asm__ __volatile__ ("mcr p15, 0, %0, c7, c5, 4" \
+#define isb(x) __asm__ __volatile__ ("mcr p15, 0, %0, c7, c5, 4" \
: : "r" (0) : "memory")
-#define dsb() __asm__ __volatile__ ("mcr p15, 0, %0, c7, c10, 4" \
+#define dsb(x) __asm__ __volatile__ ("mcr p15, 0, %0, c7, c10, 4" \
: : "r" (0) : "memory")
-#define dmb() __asm__ __volatile__ ("" : : : "memory")
+#define dmb(x) __asm__ __volatile__ ("" : : : "memory")
#else
-#define isb() __asm__ __volatile__ ("" : : : "memory")
-#define dsb() __asm__ __volatile__ ("mcr p15, 0, %0, c7, c10, 4" \
+#define isb(x) __asm__ __volatile__ ("" : : : "memory")
+#define dsb(x) __asm__ __volatile__ ("mcr p15, 0, %0, c7, c10, 4" \
: : "r" (0) : "memory")
-#define dmb() __asm__ __volatile__ ("" : : : "memory")
+#define dmb(x) __asm__ __volatile__ ("" : : : "memory")
#endif
#ifdef CONFIG_ARCH_HAS_BARRIERS
@@ -42,7 +42,7 @@
#elif defined(CONFIG_ARM_DMA_MEM_BUFFERABLE) || defined(CONFIG_SMP)
#define mb() do { dsb(); outer_sync(); } while (0)
#define rmb() dsb()
-#define wmb() mb()
+#define wmb() do { dsb(st); outer_sync(); } while (0)
#else
#define mb() barrier()
#define rmb() barrier()
@@ -54,9 +54,9 @@
#define smp_rmb() barrier()
#define smp_wmb() barrier()
#else
-#define smp_mb() dmb()
-#define smp_rmb() dmb()
-#define smp_wmb() dmb()
+#define smp_mb() dmb(ish)
+#define smp_rmb() smp_mb()
+#define smp_wmb() dmb(ishst)
#endif
#define read_barrier_depends() do { } while(0)