ARM: Add barriers to io{read,write}{8,16,32} accessors as well
The ioread/iowrite accessors also need barriers as they're used in
place of readl/writel et.al. in portable drivers. Create __iormb()
and __iowmb() which are conditionally defined to be barriers dependent
on ARM_DMA_MEM_BUFFERABLE, and always use these macros in the accessors.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/include/asm/io.h b/arch/arm/include/asm/io.h
index 3c91e7c..1261b1f9 100644
--- a/arch/arm/include/asm/io.h
+++ b/arch/arm/include/asm/io.h
@@ -193,23 +193,21 @@
cpu_to_le32(v),__mem_pci(c)))
#ifdef CONFIG_ARM_DMA_MEM_BUFFERABLE
-#define readb(c) ({ u8 __v = readb_relaxed(c); rmb(); __v; })
-#define readw(c) ({ u16 __v = readw_relaxed(c); rmb(); __v; })
-#define readl(c) ({ u32 __v = readl_relaxed(c); rmb(); __v; })
-
-#define writeb(v,c) ({ wmb(); writeb_relaxed(v,c); })
-#define writew(v,c) ({ wmb(); writew_relaxed(v,c); })
-#define writel(v,c) ({ wmb(); writel_relaxed(v,c); })
+#define __iormb() rmb()
+#define __iowmb() wmb()
#else
-#define readb(c) readb_relaxed(c)
-#define readw(c) readw_relaxed(c)
-#define readl(c) readl_relaxed(c)
-
-#define writeb(v,c) writeb_relaxed(v,c)
-#define writew(v,c) writew_relaxed(v,c)
-#define writel(v,c) writel_relaxed(v,c)
+#define __iormb() do { } while (0)
+#define __iowmb() do { } while (0)
#endif
+#define readb(c) ({ u8 __v = readb_relaxed(c); __iormb(); __v; })
+#define readw(c) ({ u16 __v = readw_relaxed(c); __iormb(); __v; })
+#define readl(c) ({ u32 __v = readl_relaxed(c); __iormb(); __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 readsb(p,d,l) __raw_readsb(__mem_pci(p),d,l)
#define readsw(p,d,l) __raw_readsw(__mem_pci(p),d,l)
#define readsl(p,d,l) __raw_readsl(__mem_pci(p),d,l)
@@ -260,13 +258,13 @@
* io{read,write}{8,16,32} macros
*/
#ifndef ioread8
-#define ioread8(p) ({ unsigned int __v = __raw_readb(p); __v; })
-#define ioread16(p) ({ unsigned int __v = le16_to_cpu((__force __le16)__raw_readw(p)); __v; })
-#define ioread32(p) ({ unsigned int __v = le32_to_cpu((__force __le32)__raw_readl(p)); __v; })
+#define ioread8(p) ({ unsigned int __v = __raw_readb(p); __iormb(); __v; })
+#define ioread16(p) ({ unsigned int __v = le16_to_cpu((__force __le16)__raw_readw(p)); __iormb(); __v; })
+#define ioread32(p) ({ unsigned int __v = le32_to_cpu((__force __le32)__raw_readl(p)); __iormb(); __v; })
-#define iowrite8(v,p) __raw_writeb(v, p)
-#define iowrite16(v,p) __raw_writew((__force __u16)cpu_to_le16(v), p)
-#define iowrite32(v,p) __raw_writel((__force __u32)cpu_to_le32(v), p)
+#define iowrite8(v,p) ({ __iowmb(); (void)__raw_writeb(v, p); })
+#define iowrite16(v,p) ({ __iowmb(); (void)__raw_writew((__force __u16)cpu_to_le16(v), p); })
+#define iowrite32(v,p) ({ __iowmb(); (void)__raw_writel((__force __u32)cpu_to_le32(v), p); })
#define ioread8_rep(p,d,c) __raw_readsb(p,d,c)
#define ioread16_rep(p,d,c) __raw_readsw(p,d,c)