--- /dev/null
+#ifndef __GENERIC_IO_H
+#define __GENERIC_IO_H
+
+#include <linux/linkage.h>
+
+/*
+ * These are the "generic" interfaces for doing new-style
+ * memory-mapped or PIO accesses. Architectures may do
+ * their own arch-optimized versions, these just act as
+ * wrappers around the old-style IO register access functions:
+ * read[bwl]/write[bwl]/in[bwl]/out[bwl]
+ *
+ * Don't include this directly, include it from <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 just encode the PIO/MMIO as part of the
+ * cookie, and 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.
+ */
+extern unsigned int fastcall ioread8(void __iomem *);
+extern unsigned int fastcall ioread16(void __iomem *);
+extern unsigned int fastcall ioread32(void __iomem *);
+
+extern void fastcall iowrite8(u8, void __iomem *);
+extern void fastcall iowrite16(u16, void __iomem *);
+extern void fastcall iowrite32(u32, void __iomem *);
+
+/* Create a virtual mapping cookie for an IO port range */
+extern void __iomem *ioport_map(unsigned int port, unsigned int nr);
+extern void ioport_unmap(void __iomem *);
+
+/* Create a virtual mapping cookie for a PCI BAR (memory or IO) */
+struct pci_dev;
+extern void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long max);
+extern void pci_iounmap(struct pci_dev *dev, void __iomem *);
+
+#endif
--- /dev/null
+/*
+ * Implement the default iomap interfaces
+ */
+#include <linux/pci.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.
+ *
+ * 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 0x10000
+#define PIO_MASK 0x0ffff
+#define PIO_RESERVED 0x40000
+
+/*
+ * 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));
+}
+
+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));
+}
+
+/* Create a virtual mapping cookie for an IO port range */
+void __iomem *ioport_map(unsigned int 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 */
+}
+
+/* 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));
+}
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