diff options
| author | Andre Przywara <andre.przywara@arm.com> | 2014-11-14 18:54:11 +0300 |
|---|---|---|
| committer | Will Deacon <will.deacon@arm.com> | 2014-11-25 18:56:42 +0300 |
| commit | 5afaa1fc1b320cec48affa7e6949f2493f875c12 (patch) | |
| tree | 6d7d20ce61c2939548c6b5105bc5130c4f7191ac /arch/arm64/include/asm/io.h | |
| parent | 301bcfac42897dbd1b0b3c1be49f24654a1bc49e (diff) | |
| download | linux-5afaa1fc1b320cec48affa7e6949f2493f875c12.tar.xz | |
arm64: add Cortex-A57 erratum 832075 workaround
The ARM erratum 832075 applies to certain revisions of Cortex-A57,
one of the workarounds is to change device loads into using
load-aquire semantics.
This is achieved using the alternatives framework.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Diffstat (limited to 'arch/arm64/include/asm/io.h')
| -rw-r--r-- | arch/arm64/include/asm/io.h | 23 |
1 files changed, 19 insertions, 4 deletions
diff --git a/arch/arm64/include/asm/io.h b/arch/arm64/include/asm/io.h index 79f1d519221f..75825b63464d 100644 --- a/arch/arm64/include/asm/io.h +++ b/arch/arm64/include/asm/io.h @@ -28,6 +28,8 @@ #include <asm/barrier.h> #include <asm/pgtable.h> #include <asm/early_ioremap.h> +#include <asm/alternative.h> +#include <asm/cpufeature.h> #include <xen/xen.h> @@ -57,28 +59,41 @@ static inline void __raw_writeq(u64 val, volatile void __iomem *addr) static inline u8 __raw_readb(const volatile void __iomem *addr) { u8 val; - asm volatile("ldrb %w0, [%1]" : "=r" (val) : "r" (addr)); + asm volatile(ALTERNATIVE("ldrb %w0, [%1]", + "ldarb %w0, [%1]", + ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE) + : "=r" (val) : "r" (addr)); return val; } static inline u16 __raw_readw(const volatile void __iomem *addr) { u16 val; - asm volatile("ldrh %w0, [%1]" : "=r" (val) : "r" (addr)); + + asm volatile(ALTERNATIVE("ldrh %w0, [%1]", + "ldarh %w0, [%1]", + ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE) + : "=r" (val) : "r" (addr)); return val; } static inline u32 __raw_readl(const volatile void __iomem *addr) { u32 val; - asm volatile("ldr %w0, [%1]" : "=r" (val) : "r" (addr)); + asm volatile(ALTERNATIVE("ldr %w0, [%1]", + "ldar %w0, [%1]", + ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE) + : "=r" (val) : "r" (addr)); return val; } static inline u64 __raw_readq(const volatile void __iomem *addr) { u64 val; - asm volatile("ldr %0, [%1]" : "=r" (val) : "r" (addr)); + asm volatile(ALTERNATIVE("ldr %0, [%1]", + "ldar %0, [%1]", + ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE) + : "=r" (val) : "r" (addr)); return val; } |