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-rw-r--r--lib/iomap.c212
1 files changed, 212 insertions, 0 deletions
diff --git a/lib/iomap.c b/lib/iomap.c
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index 000000000000..5e74390852b0
--- /dev/null
+++ b/lib/iomap.c
@@ -0,0 +1,212 @@
+/*
+ * Implement the default iomap interfaces
+ *
+ * (C) Copyright 2004 Linus Torvalds
+ */
+#include <linux/pci.h>
+#include <linux/module.h>
+#include <asm/io.h>
+
+/*
+ * Read/write from/to an (offsettable) iomem cookie. It might be a PIO
+ * access or a MMIO access, these functions don't care. The info is
+ * encoded in the hardware mapping set up by the mapping functions
+ * (or the cookie itself, depending on implementation and hw).
+ *
+ * The generic routines don't assume any hardware mappings, and just
+ * encode the PIO/MMIO as part of the cookie. They coldly assume that
+ * the MMIO IO mappings are not in the low address range.
+ *
+ * Architectures for which this is not true can't use this generic
+ * implementation and should do their own copy.
+ */
+
+#ifndef HAVE_ARCH_PIO_SIZE
+/*
+ * We encode the physical PIO addresses (0-0xffff) into the
+ * pointer by offsetting them with a constant (0x10000) and
+ * assuming that all the low addresses are always PIO. That means
+ * we can do some sanity checks on the low bits, and don't
+ * need to just take things for granted.
+ */
+#define PIO_OFFSET 0x10000UL
+#define PIO_MASK 0x0ffffUL
+#define PIO_RESERVED 0x40000UL
+#endif
+
+/*
+ * Ugly macros are a way of life.
+ */
+#define VERIFY_PIO(port) BUG_ON((port & ~PIO_MASK) != PIO_OFFSET)
+
+#define IO_COND(addr, is_pio, is_mmio) do { \
+ unsigned long port = (unsigned long __force)addr; \
+ if (port < PIO_RESERVED) { \
+ VERIFY_PIO(port); \
+ port &= PIO_MASK; \
+ is_pio; \
+ } else { \
+ is_mmio; \
+ } \
+} while (0)
+
+unsigned int fastcall ioread8(void __iomem *addr)
+{
+ IO_COND(addr, return inb(port), return readb(addr));
+}
+unsigned int fastcall ioread16(void __iomem *addr)
+{
+ IO_COND(addr, return inw(port), return readw(addr));
+}
+unsigned int fastcall ioread32(void __iomem *addr)
+{
+ IO_COND(addr, return inl(port), return readl(addr));
+}
+EXPORT_SYMBOL(ioread8);
+EXPORT_SYMBOL(ioread16);
+EXPORT_SYMBOL(ioread32);
+
+void fastcall iowrite8(u8 val, void __iomem *addr)
+{
+ IO_COND(addr, outb(val,port), writeb(val, addr));
+}
+void fastcall iowrite16(u16 val, void __iomem *addr)
+{
+ IO_COND(addr, outw(val,port), writew(val, addr));
+}
+void fastcall iowrite32(u32 val, void __iomem *addr)
+{
+ IO_COND(addr, outl(val,port), writel(val, addr));
+}
+EXPORT_SYMBOL(iowrite8);
+EXPORT_SYMBOL(iowrite16);
+EXPORT_SYMBOL(iowrite32);
+
+/*
+ * These are the "repeat MMIO read/write" functions.
+ * Note the "__raw" accesses, since we don't want to
+ * convert to CPU byte order. We write in "IO byte
+ * order" (we also don't have IO barriers).
+ */
+static inline void mmio_insb(void __iomem *addr, u8 *dst, int count)
+{
+ while (--count >= 0) {
+ u8 data = __raw_readb(addr);
+ *dst = data;
+ dst++;
+ }
+}
+static inline void mmio_insw(void __iomem *addr, u16 *dst, int count)
+{
+ while (--count >= 0) {
+ u16 data = __raw_readw(addr);
+ *dst = data;
+ dst++;
+ }
+}
+static inline void mmio_insl(void __iomem *addr, u32 *dst, int count)
+{
+ while (--count >= 0) {
+ u32 data = __raw_readl(addr);
+ *dst = data;
+ dst++;
+ }
+}
+
+static inline void mmio_outsb(void __iomem *addr, const u8 *src, int count)
+{
+ while (--count >= 0) {
+ __raw_writeb(*src, addr);
+ src++;
+ }
+}
+static inline void mmio_outsw(void __iomem *addr, const u16 *src, int count)
+{
+ while (--count >= 0) {
+ __raw_writew(*src, addr);
+ src++;
+ }
+}
+static inline void mmio_outsl(void __iomem *addr, const u32 *src, int count)
+{
+ while (--count >= 0) {
+ __raw_writel(*src, addr);
+ src++;
+ }
+}
+
+void fastcall ioread8_rep(void __iomem *addr, void *dst, unsigned long count)
+{
+ IO_COND(addr, insb(port,dst,count), mmio_insb(addr, dst, count));
+}
+void fastcall ioread16_rep(void __iomem *addr, void *dst, unsigned long count)
+{
+ IO_COND(addr, insw(port,dst,count), mmio_insw(addr, dst, count));
+}
+void fastcall ioread32_rep(void __iomem *addr, void *dst, unsigned long count)
+{
+ IO_COND(addr, insl(port,dst,count), mmio_insl(addr, dst, count));
+}
+EXPORT_SYMBOL(ioread8_rep);
+EXPORT_SYMBOL(ioread16_rep);
+EXPORT_SYMBOL(ioread32_rep);
+
+void fastcall iowrite8_rep(void __iomem *addr, const void *src, unsigned long count)
+{
+ IO_COND(addr, outsb(port, src, count), mmio_outsb(addr, src, count));
+}
+void fastcall iowrite16_rep(void __iomem *addr, const void *src, unsigned long count)
+{
+ IO_COND(addr, outsw(port, src, count), mmio_outsw(addr, src, count));
+}
+void fastcall iowrite32_rep(void __iomem *addr, const void *src, unsigned long count)
+{
+ IO_COND(addr, outsl(port, src,count), mmio_outsl(addr, src, count));
+}
+EXPORT_SYMBOL(iowrite8_rep);
+EXPORT_SYMBOL(iowrite16_rep);
+EXPORT_SYMBOL(iowrite32_rep);
+
+/* Create a virtual mapping cookie for an IO port range */
+void __iomem *ioport_map(unsigned long port, unsigned int nr)
+{
+ if (port > PIO_MASK)
+ return NULL;
+ return (void __iomem *) (unsigned long) (port + PIO_OFFSET);
+}
+
+void ioport_unmap(void __iomem *addr)
+{
+ /* Nothing to do */
+}
+EXPORT_SYMBOL(ioport_map);
+EXPORT_SYMBOL(ioport_unmap);
+
+/* Create a virtual mapping cookie for a PCI BAR (memory or IO) */
+void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long maxlen)
+{
+ unsigned long start = pci_resource_start(dev, bar);
+ unsigned long len = pci_resource_len(dev, bar);
+ unsigned long flags = pci_resource_flags(dev, bar);
+
+ if (!len || !start)
+ return NULL;
+ if (maxlen && len > maxlen)
+ len = maxlen;
+ if (flags & IORESOURCE_IO)
+ return ioport_map(start, len);
+ if (flags & IORESOURCE_MEM) {
+ if (flags & IORESOURCE_CACHEABLE)
+ return ioremap(start, len);
+ return ioremap_nocache(start, len);
+ }
+ /* What? */
+ return NULL;
+}
+
+void pci_iounmap(struct pci_dev *dev, void __iomem * addr)
+{
+ IO_COND(addr, /* nothing */, iounmap(addr));
+}
+EXPORT_SYMBOL(pci_iomap);
+EXPORT_SYMBOL(pci_iounmap);