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-rw-r--r--arch/arm/include/asm/io.h77
1 files changed, 70 insertions, 7 deletions
diff --git a/arch/arm/include/asm/io.h b/arch/arm/include/asm/io.h
index 815c669fec0..652b56086de 100644
--- a/arch/arm/include/asm/io.h
+++ b/arch/arm/include/asm/io.h
@@ -47,13 +47,68 @@ extern void __raw_readsb(const void __iomem *addr, void *data, int bytelen);
extern void __raw_readsw(const void __iomem *addr, void *data, int wordlen);
extern void __raw_readsl(const void __iomem *addr, void *data, int longlen);
-#define __raw_writeb(v,a) ((void)(__chk_io_ptr(a), *(volatile unsigned char __force *)(a) = (v)))
-#define __raw_writew(v,a) ((void)(__chk_io_ptr(a), *(volatile unsigned short __force *)(a) = (v)))
-#define __raw_writel(v,a) ((void)(__chk_io_ptr(a), *(volatile unsigned int __force *)(a) = (v)))
+#if __LINUX_ARM_ARCH__ < 6
+/*
+ * Half-word accesses are problematic with RiscPC due to limitations of
+ * the bus. Rather than special-case the machine, just let the compiler
+ * generate the access for CPUs prior to ARMv6.
+ */
+#define __raw_readw(a) (__chk_io_ptr(a), *(volatile unsigned short __force *)(a))
+#define __raw_writew(v,a) ((void)(__chk_io_ptr(a), *(volatile unsigned short __force *)(a) = (v)))
+#else
+/*
+ * When running under a hypervisor, we want to avoid I/O accesses with
+ * writeback addressing modes as these incur a significant performance
+ * overhead (the address generation must be emulated in software).
+ */
+static inline void __raw_writew(u16 val, volatile void __iomem *addr)
+{
+ asm volatile("strh %1, %0"
+ : "+Q" (*(volatile u16 __force *)addr)
+ : "r" (val));
+}
+
+static inline u16 __raw_readw(const volatile void __iomem *addr)
+{
+ u16 val;
+ asm volatile("ldrh %1, %0"
+ : "+Q" (*(volatile u16 __force *)addr),
+ "=r" (val));
+ return val;
+}
+#endif
+
+static inline void __raw_writeb(u8 val, volatile void __iomem *addr)
+{
+ asm volatile("strb %1, %0"
+ : "+Qo" (*(volatile u8 __force *)addr)
+ : "r" (val));
+}
+
+static inline void __raw_writel(u32 val, volatile void __iomem *addr)
+{
+ asm volatile("str %1, %0"
+ : "+Qo" (*(volatile u32 __force *)addr)
+ : "r" (val));
+}
+
+static inline u8 __raw_readb(const volatile void __iomem *addr)
+{
+ u8 val;
+ asm volatile("ldrb %1, %0"
+ : "+Qo" (*(volatile u8 __force *)addr),
+ "=r" (val));
+ return val;
+}
-#define __raw_readb(a) (__chk_io_ptr(a), *(volatile unsigned char __force *)(a))
-#define __raw_readw(a) (__chk_io_ptr(a), *(volatile unsigned short __force *)(a))
-#define __raw_readl(a) (__chk_io_ptr(a), *(volatile unsigned int __force *)(a))
+static inline u32 __raw_readl(const volatile void __iomem *addr)
+{
+ u32 val;
+ asm volatile("ldr %1, %0"
+ : "+Qo" (*(volatile u32 __force *)addr),
+ "=r" (val));
+ return val;
+}
/*
* Architecture ioremap implementation.
@@ -113,11 +168,19 @@ static inline void __iomem *__typesafe_io(unsigned long addr)
#define __iowmb() do { } while (0)
#endif
+/* PCI fixed i/o mapping */
+#define PCI_IO_VIRT_BASE 0xfee00000
+
+extern int pci_ioremap_io(unsigned int offset, phys_addr_t phys_addr);
+
/*
* Now, pick up the machine-defined IO definitions
*/
#ifdef CONFIG_NEED_MACH_IO_H
#include <mach/io.h>
+#elif defined(CONFIG_PCI)
+#define IO_SPACE_LIMIT ((resource_size_t)0xfffff)
+#define __io(a) __typesafe_io(PCI_IO_VIRT_BASE + ((a) & IO_SPACE_LIMIT))
#else
#define __io(a) __typesafe_io((a) & IO_SPACE_LIMIT)
#endif
@@ -311,7 +374,7 @@ extern void pci_iounmap(struct pci_dev *dev, void __iomem *addr);
#ifdef CONFIG_MMU
#define ARCH_HAS_VALID_PHYS_ADDR_RANGE
-extern int valid_phys_addr_range(unsigned long addr, size_t size);
+extern int valid_phys_addr_range(phys_addr_t addr, size_t size);
extern int valid_mmap_phys_addr_range(unsigned long pfn, size_t size);
extern int devmem_is_allowed(unsigned long pfn);
#endif