alistair23-linux/lib/iomap.c
James Bottomley dae409a277 [PATCH] add Big Endian variants of ioread/iowrite
In the new io infrastructure, all of our operators are expecting the
underlying device to be little endian (because the PCI bus, their main
consumer, is LE).

However, there are a fair few devices and busses in the world that are
actually Big Endian.  There's even evidence that some of these BE bus and
chip types are attached to LE systems.  Thus, there's a need for a BE
equivalent of our io{read,write}{16,32} operations.

The attached patch adds this as io{read,write}{16,32}be.  When it's in,
I'll add the first consume (the 53c700 SCSI chip driver).

Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-04-16 15:25:54 -07:00

233 lines
6.2 KiB
C

/*
* 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 ioread16be(void __iomem *addr)
{
IO_COND(addr, return inw(port), return be16_to_cpu(__raw_readw(addr)));
}
unsigned int fastcall ioread32(void __iomem *addr)
{
IO_COND(addr, return inl(port), return readl(addr));
}
unsigned int fastcall ioread32be(void __iomem *addr)
{
IO_COND(addr, return inl(port), return be32_to_cpu(__raw_readl(addr)));
}
EXPORT_SYMBOL(ioread8);
EXPORT_SYMBOL(ioread16);
EXPORT_SYMBOL(ioread16be);
EXPORT_SYMBOL(ioread32);
EXPORT_SYMBOL(ioread32be);
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 iowrite16be(u16 val, void __iomem *addr)
{
IO_COND(addr, outw(val,port), __raw_writew(cpu_to_be16(val), addr));
}
void fastcall iowrite32(u32 val, void __iomem *addr)
{
IO_COND(addr, outl(val,port), writel(val, addr));
}
void fastcall iowrite32be(u32 val, void __iomem *addr)
{
IO_COND(addr, outl(val,port), __raw_writel(cpu_to_be32(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).
*/
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);