[PATCHv6 1/5] arm64: io: Use asm-generic high level MMIO accessors

Sai Prakash Ranjan quic_saipraka at quicinc.com
Mon Dec 6 22:54:45 PST 2021


Remove custom arm64 MMIO accessors read{b,w,l,q} and their relaxed
versions in support to use asm-generic defined accessors. Also define
one set of IO barriers (ar/bw version) used by asm-generic code to
override the arm64 specific variants.

Suggested-by: Arnd Bergmann <arnd at arndb.de>
Signed-off-by: Sai Prakash Ranjan <quic_saipraka at quicinc.com>
---
 arch/arm64/include/asm/io.h | 41 ++++++++-----------------------------
 1 file changed, 8 insertions(+), 33 deletions(-)

diff --git a/arch/arm64/include/asm/io.h b/arch/arm64/include/asm/io.h
index 7fd836bea7eb..1b436810d779 100644
--- a/arch/arm64/include/asm/io.h
+++ b/arch/arm64/include/asm/io.h
@@ -91,7 +91,7 @@ static inline u64 __raw_readq(const volatile void __iomem *addr)
 }
 
 /* IO barriers */
-#define __iormb(v)							\
+#define __io_ar(v)							\
 ({									\
 	unsigned long tmp;						\
 									\
@@ -108,39 +108,14 @@ static inline u64 __raw_readq(const volatile void __iomem *addr)
 		     : "memory");					\
 })
 
-#define __io_par(v)		__iormb(v)
-#define __iowmb()		dma_wmb()
-#define __iomb()		dma_mb()
-
-/*
- * Relaxed I/O memory access primitives. These follow the Device memory
- * ordering rules but do not guarantee any ordering relative to Normal memory
- * accesses.
- */
-#define readb_relaxed(c)	({ u8  __r = __raw_readb(c); __r; })
-#define readw_relaxed(c)	({ u16 __r = le16_to_cpu((__force __le16)__raw_readw(c)); __r; })
-#define readl_relaxed(c)	({ u32 __r = le32_to_cpu((__force __le32)__raw_readl(c)); __r; })
-#define readq_relaxed(c)	({ u64 __r = le64_to_cpu((__force __le64)__raw_readq(c)); __r; })
+#define __io_bw()		dma_wmb()
+#define __io_br(v)
+#define __io_aw(v)
 
-#define writeb_relaxed(v,c)	((void)__raw_writeb((v),(c)))
-#define writew_relaxed(v,c)	((void)__raw_writew((__force u16)cpu_to_le16(v),(c)))
-#define writel_relaxed(v,c)	((void)__raw_writel((__force u32)cpu_to_le32(v),(c)))
-#define writeq_relaxed(v,c)	((void)__raw_writeq((__force u64)cpu_to_le64(v),(c)))
-
-/*
- * I/O memory access primitives. Reads are ordered relative to any
- * following Normal memory access. Writes are ordered relative to any prior
- * Normal memory access.
- */
-#define readb(c)		({ u8  __v = readb_relaxed(c); __iormb(__v); __v; })
-#define readw(c)		({ u16 __v = readw_relaxed(c); __iormb(__v); __v; })
-#define readl(c)		({ u32 __v = readl_relaxed(c); __iormb(__v); __v; })
-#define readq(c)		({ u64 __v = readq_relaxed(c); __iormb(__v); __v; })
-
-#define writeb(v,c)		({ __iowmb(); writeb_relaxed((v),(c)); })
-#define writew(v,c)		({ __iowmb(); writew_relaxed((v),(c)); })
-#define writel(v,c)		({ __iowmb(); writel_relaxed((v),(c)); })
-#define writeq(v,c)		({ __iowmb(); writeq_relaxed((v),(c)); })
+/* arm64-specific, don't use in portable drivers */
+#define __iormb(v)		__io_ar(v)
+#define __iowmb()		__io_bw()
+#define __iomb()		dma_mb()
 
 /*
  *  I/O port access primitives.
-- 
2.33.1




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