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root/include/asm-x86/io_32.h

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INCLUDED FROM


DEFINITIONS

This source file includes following definitions.
  1. virt_to_phys
  2. phys_to_virt
  3. ioremap
  4. memset_io
  5. memcpy_fromio
  6. memcpy_toio
  7. flush_write_buffers
  8. slow_down_io

#ifndef ASM_X86__IO_32_H
#define ASM_X86__IO_32_H

#include <linux/string.h>
#include <linux/compiler.h>

/*
 * This file contains the definitions for the x86 IO instructions
 * inb/inw/inl/outb/outw/outl and the "string versions" of the same
 * (insb/insw/insl/outsb/outsw/outsl). You can also use "pausing"
 * versions of the single-IO instructions (inb_p/inw_p/..).
 *
 * This file is not meant to be obfuscating: it's just complicated
 * to (a) handle it all in a way that makes gcc able to optimize it
 * as well as possible and (b) trying to avoid writing the same thing
 * over and over again with slight variations and possibly making a
 * mistake somewhere.
 */

/*
 * Thanks to James van Artsdalen for a better timing-fix than
 * the two short jumps: using outb's to a nonexistent port seems
 * to guarantee better timings even on fast machines.
 *
 * On the other hand, I'd like to be sure of a non-existent port:
 * I feel a bit unsafe about using 0x80 (should be safe, though)
 *
 *              Linus
 */

 /*
  *  Bit simplified and optimized by Jan Hubicka
  *  Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999.
  *
  *  isa_memset_io, isa_memcpy_fromio, isa_memcpy_toio added,
  *  isa_read[wl] and isa_write[wl] fixed
  *  - Arnaldo Carvalho de Melo <acme@conectiva.com.br>
  */

#define IO_SPACE_LIMIT 0xffff

#define XQUAD_PORTIO_BASE 0xfe400000
#define XQUAD_PORTIO_QUAD 0x40000  /* 256k per quad. */

#ifdef __KERNEL__

#include <asm-generic/iomap.h>

#include <linux/vmalloc.h>

/*
 * Convert a virtual cached pointer to an uncached pointer
 */
#define xlate_dev_kmem_ptr(p)   p

/**
 *      virt_to_phys    -       map virtual addresses to physical
 *      @address: address to remap
 *
 *      The returned physical address is the physical (CPU) mapping for
 *      the memory address given. It is only valid to use this function on
 *      addresses directly mapped or allocated via kmalloc.
 *
 *      This function does not give bus mappings for DMA transfers. In
 *      almost all conceivable cases a device driver should not be using
 *      this function
 */

static inline unsigned long virt_to_phys(volatile void *address)
{
        return __pa(address);
}

/**
 *      phys_to_virt    -       map physical address to virtual
 *      @address: address to remap
 *
 *      The returned virtual address is a current CPU mapping for
 *      the memory address given. It is only valid to use this function on
 *      addresses that have a kernel mapping
 *
 *      This function does not handle bus mappings for DMA transfers. In
 *      almost all conceivable cases a device driver should not be using
 *      this function
 */

static inline void *phys_to_virt(unsigned long address)
{
        return __va(address);
}

/*
 * Change "struct page" to physical address.
 */
#define page_to_phys(page)    ((dma_addr_t)page_to_pfn(page) << PAGE_SHIFT)

/**
 * ioremap     -   map bus memory into CPU space
 * @offset:    bus address of the memory
 * @size:      size of the resource to map
 *
 * ioremap performs a platform specific sequence of operations to
 * make bus memory CPU accessible via the readb/readw/readl/writeb/
 * writew/writel functions and the other mmio helpers. The returned
 * address is not guaranteed to be usable directly as a virtual
 * address.
 *
 * If the area you are trying to map is a PCI BAR you should have a
 * look at pci_iomap().
 */
extern void __iomem *ioremap_nocache(resource_size_t offset, unsigned long size);
extern void __iomem *ioremap_cache(resource_size_t offset, unsigned long size);
extern void __iomem *ioremap_prot(resource_size_t offset, unsigned long size,
                                unsigned long prot_val);

/*
 * The default ioremap() behavior is non-cached:
 */
static inline void __iomem *ioremap(resource_size_t offset, unsigned long size)
{
        return ioremap_nocache(offset, size);
}

extern void iounmap(volatile void __iomem *addr);

/*
 * ISA I/O bus memory addresses are 1:1 with the physical address.
 */
#define isa_virt_to_bus virt_to_phys
#define isa_page_to_bus page_to_phys
#define isa_bus_to_virt phys_to_virt

/*
 * However PCI ones are not necessarily 1:1 and therefore these interfaces
 * are forbidden in portable PCI drivers.
 *
 * Allow them on x86 for legacy drivers, though.
 */
#define virt_to_bus virt_to_phys
#define bus_to_virt phys_to_virt

static inline void
memset_io(volatile void __iomem *addr, unsigned char val, int count)
{
        memset((void __force *)addr, val, count);
}

static inline void
memcpy_fromio(void *dst, const volatile void __iomem *src, int count)
{
        __memcpy(dst, (const void __force *)src, count);
}

static inline void
memcpy_toio(volatile void __iomem *dst, const void *src, int count)
{
        __memcpy((void __force *)dst, src, count);
}

/*
 * ISA space is 'always mapped' on a typical x86 system, no need to
 * explicitly ioremap() it. The fact that the ISA IO space is mapped
 * to PAGE_OFFSET is pure coincidence - it does not mean ISA values
 * are physical addresses. The following constant pointer can be
 * used as the IO-area pointer (it can be iounmapped as well, so the
 * analogy with PCI is quite large):
 */
#define __ISA_IO_base ((char __iomem *)(PAGE_OFFSET))

/*
 *      Cache management
 *
 *      This needed for two cases
 *      1. Out of order aware processors
 *      2. Accidentally out of order processors (PPro errata #51)
 */

#if defined(CONFIG_X86_OOSTORE) || defined(CONFIG_X86_PPRO_FENCE)

static inline void flush_write_buffers(void)
{
        asm volatile("lock; addl $0,0(%%esp)": : :"memory");
}

#else

#define flush_write_buffers() do { } while (0)

#endif

#endif /* __KERNEL__ */

extern void native_io_delay(void);

extern int io_delay_type;
extern void io_delay_init(void);

#if defined(CONFIG_PARAVIRT)
#include <asm/paravirt.h>
#else

static inline void slow_down_io(void)
{
        native_io_delay();
#ifdef REALLY_SLOW_IO
        native_io_delay();
        native_io_delay();
        native_io_delay();
#endif
}

#endif

#define __BUILDIO(bwl, bw, type)                                \
static inline void out##bwl(unsigned type value, int port)      \
{                                                               \
        out##bwl##_local(value, port);                          \
}                                                               \
                                                                \
static inline unsigned type in##bwl(int port)                   \
{                                                               \
        return in##bwl##_local(port);                           \
}

#define BUILDIO(bwl, bw, type)                                          \
static inline void out##bwl##_local(unsigned type value, int port)      \
{                                                                       \
        asm volatile("out" #bwl " %" #bw "0, %w1"               \
                     : : "a"(value), "Nd"(port));                       \
}                                                                       \
                                                                        \
static inline unsigned type in##bwl##_local(int port)                   \
{                                                                       \
        unsigned type value;                                            \
        asm volatile("in" #bwl " %w1, %" #bw "0"                \
                     : "=a"(value) : "Nd"(port));                       \
        return value;                                                   \
}                                                                       \
                                                                        \
static inline void out##bwl##_local_p(unsigned type value, int port)    \
{                                                                       \
        out##bwl##_local(value, port);                                  \
        slow_down_io();                                                 \
}                                                                       \
                                                                        \
static inline unsigned type in##bwl##_local_p(int port)                 \
{                                                                       \
        unsigned type value = in##bwl##_local(port);                    \
        slow_down_io();                                                 \
        return value;                                                   \
}                                                                       \
                                                                        \
__BUILDIO(bwl, bw, type)                                                \
                                                                        \
static inline void out##bwl##_p(unsigned type value, int port)          \
{                                                                       \
        out##bwl(value, port);                                          \
        slow_down_io();                                                 \
}                                                                       \
                                                                        \
static inline unsigned type in##bwl##_p(int port)                       \
{                                                                       \
        unsigned type value = in##bwl(port);                            \
        slow_down_io();                                                 \
        return value;                                                   \
}                                                                       \
                                                                        \
static inline void outs##bwl(int port, const void *addr, unsigned long count) \
{                                                                       \
        asm volatile("rep; outs" #bwl                                   \
                     : "+S"(addr), "+c"(count) : "d"(port));            \
}                                                                       \
                                                                        \
static inline void ins##bwl(int port, void *addr, unsigned long count)  \
{                                                                       \
        asm volatile("rep; ins" #bwl                                    \
                     : "+D"(addr), "+c"(count) : "d"(port));            \
}

BUILDIO(b, b, char)
BUILDIO(w, w, short)
BUILDIO(l, , int)

#endif /* ASM_X86__IO_32_H */

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