The inX() I/O accessors must enforce ordering against subsequent calls to the delay() routines, so that a read-back from a device can be used to postpone a subsequent write to the same device.
On some architectures, including arm64, this ordering can only be achieved by creating a dependency on the value returned by the inX() operation, so we need to pass the value we read to the __io_par() macro in this case. Reported-by: Andrew Murray <[email protected]> Signed-off-by: Will Deacon <[email protected]> --- include/asm-generic/io.h | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/include/asm-generic/io.h b/include/asm-generic/io.h index d356f802945a..b5737c0d8316 100644 --- a/include/asm-generic/io.h +++ b/include/asm-generic/io.h @@ -65,7 +65,7 @@ #endif #ifndef __io_par -#define __io_par() __io_ar() +#define __io_par(v) __io_ar() #endif @@ -471,7 +471,7 @@ static inline u8 inb(unsigned long addr) __io_pbr(); val = __raw_readb(PCI_IOBASE + addr); - __io_par(); + __io_par(val); return val; } #endif @@ -484,7 +484,7 @@ static inline u16 inw(unsigned long addr) __io_pbr(); val = __le16_to_cpu(__raw_readw(PCI_IOBASE + addr)); - __io_par(); + __io_par(val); return val; } #endif @@ -497,7 +497,7 @@ static inline u32 inl(unsigned long addr) __io_pbr(); val = __le32_to_cpu(__raw_readl(PCI_IOBASE + addr)); - __io_par(); + __io_par(val); return val; } #endif -- 2.11.0
