iomap.c

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/*
 * Implement the default iomap interfaces
 *
 * (C) Copyright 2004 Linus Torvalds
 */
#include <linux/pci.h>
#include <linux/io.h>

#include <linux/module.h>

#ifdef DDE_LINUX
#include "local.h"
#endif

/*
 * 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

static void bad_io_access(unsigned long port, const char *access)
{
        static int count = 10;
        if (count) {
                count--;
                WARN(1, KERN_ERR "Bad IO access at port %#lx (%s)\n", port, access);
        }
}

/*
 * Ugly macros are a way of life.
 */
#ifdef DDE_LINUX
/* DDE_LINUX maps io ports to [0xf0000000, 0xf0040000], so we also need
 * to check the lower bounds of port addresses.
 */
#define IO_COND(addr, is_pio, is_mmio) do {                     \
        unsigned long port = (unsigned long __force)addr;       \
        if (port > PIO_OFFSET && port < PIO_RESERVED) {         \
                port &= PIO_MASK;                               \
                is_pio;                                         \
        } else {                                                \
                is_mmio;                                        \
        }       \
} while (0)
#else
#define IO_COND(addr, is_pio, is_mmio) do {                     \
        unsigned long port = (unsigned long __force)addr;       \
        if (port >= PIO_RESERVED) {                             \
                is_mmio;                                        \
        } else if (port > PIO_OFFSET) {                         \
                port &= PIO_MASK;                               \
                is_pio;                                         \
        } else                                                  \
                bad_io_access(port, #is_pio );                  \
} while (0)
#endif

#ifndef pio_read16be
#define pio_read16be(port) swab16(inw(port))
#define pio_read32be(port) swab32(inl(port))
#endif

#ifndef mmio_read16be
#define mmio_read16be(addr) be16_to_cpu(__raw_readw(addr))
#define mmio_read32be(addr) be32_to_cpu(__raw_readl(addr))
#endif

unsigned int ioread8(void __iomem *addr)
{
        IO_COND(addr, return inb(port), return readb(addr));
        return 0xff;
}
unsigned int ioread16(void __iomem *addr)
{
        IO_COND(addr, return inw(port), return readw(addr));
        return 0xffff;
}
unsigned int ioread16be(void __iomem *addr)
{
        IO_COND(addr, return pio_read16be(port), return mmio_read16be(addr));
        return 0xffff;
}
unsigned int ioread32(void __iomem *addr)
{
        IO_COND(addr, return inl(port), return readl(addr));
        return 0xffffffff;
}
unsigned int ioread32be(void __iomem *addr)
{
        IO_COND(addr, return pio_read32be(port), return mmio_read32be(addr));
        return 0xffffffff;
}
EXPORT_SYMBOL(ioread8);
EXPORT_SYMBOL(ioread16);
EXPORT_SYMBOL(ioread16be);
EXPORT_SYMBOL(ioread32);
EXPORT_SYMBOL(ioread32be);

#ifndef pio_write16be
#define pio_write16be(val,port) outw(swab16(val),port)
#define pio_write32be(val,port) outl(swab32(val),port)
#endif

#ifndef mmio_write16be
#define mmio_write16be(val,port) __raw_writew(be16_to_cpu(val),port)
#define mmio_write32be(val,port) __raw_writel(be32_to_cpu(val),port)
#endif

void iowrite8(u8 val, void __iomem *addr)
{
        IO_COND(addr, outb(val,port), writeb(val, addr));
}
void iowrite16(u16 val, void __iomem *addr)
{
        IO_COND(addr, outw(val,port), writew(val, addr));
}
void iowrite16be(u16 val, void __iomem *addr)
{
        IO_COND(addr, pio_write16be(val,port), mmio_write16be(val, addr));
}
void iowrite32(u32 val, void __iomem *addr)
{
        IO_COND(addr, outl(val,port), writel(val, addr));
}
void iowrite32be(u32 val, void __iomem *addr)
{
        IO_COND(addr, pio_write32be(val,port), mmio_write32be(val, addr));
}
EXPORT_SYMBOL(iowrite8);
EXPORT_SYMBOL(iowrite16);
EXPORT_SYMBOL(iowrite16be);
EXPORT_SYMBOL(iowrite32);
EXPORT_SYMBOL(iowrite32be);

/*
 * 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).
 */
#ifndef mmio_insb
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++;
        }
}
#endif

#ifndef mmio_outsb
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++;
        }
}
#endif

void ioread8_rep(void __iomem *addr, void *dst, unsigned long count)
{
        IO_COND(addr, insb(port,dst,count), mmio_insb(addr, dst, count));
}
void ioread16_rep(void __iomem *addr, void *dst, unsigned long count)
{
        IO_COND(addr, insw(port,dst,count), mmio_insw(addr, dst, count));
}
void 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 iowrite8_rep(void __iomem *addr, const void *src, unsigned long count)
{
        IO_COND(addr, outsb(port, src, count), mmio_outsb(addr, src, count));
}
void iowrite16_rep(void __iomem *addr, const void *src, unsigned long count)
{
        IO_COND(addr, outsw(port, src, count), mmio_outsw(addr, src, count));
}
void 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);

/**
 * pci_iomap - create a virtual mapping cookie for a PCI BAR
 * @dev: PCI device that owns the BAR
 * @bar: BAR number
 * @maxlen: length of the memory to map
 *
 * Using this function you will get a __iomem address to your device BAR.
 * You can access it using ioread*() and iowrite*(). These functions hide
 * the details if this is a MMIO or PIO address space and will just do what
 * you expect from them in the correct way.
 *
 * @maxlen specifies the maximum length to map. If you want to get access to
 * the complete BAR without checking for its length first, pass %0 here.
 * */
void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long maxlen)
{
        resource_size_t start = pci_resource_start(dev, bar);
        resource_size_t 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);

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