linux/include/asm-x86/io_32.h
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   1#ifndef _ASM_IO_H
   2#define _ASM_IO_H
   3
   4#include <linux/string.h>
   5#include <linux/compiler.h>
   6
   7/*
   8 * This file contains the definitions for the x86 IO instructions
   9 * inb/inw/inl/outb/outw/outl and the "string versions" of the same
  10 * (insb/insw/insl/outsb/outsw/outsl). You can also use "pausing"
  11 * versions of the single-IO instructions (inb_p/inw_p/..).
  12 *
  13 * This file is not meant to be obfuscating: it's just complicated
  14 * to (a) handle it all in a way that makes gcc able to optimize it
  15 * as well as possible and (b) trying to avoid writing the same thing
  16 * over and over again with slight variations and possibly making a
  17 * mistake somewhere.
  18 */
  19
  20/*
  21 * Thanks to James van Artsdalen for a better timing-fix than
  22 * the two short jumps: using outb's to a nonexistent port seems
  23 * to guarantee better timings even on fast machines.
  24 *
  25 * On the other hand, I'd like to be sure of a non-existent port:
  26 * I feel a bit unsafe about using 0x80 (should be safe, though)
  27 *
  28 *              Linus
  29 */
  30
  31 /*
  32  *  Bit simplified and optimized by Jan Hubicka
  33  *  Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999.
  34  *
  35  *  isa_memset_io, isa_memcpy_fromio, isa_memcpy_toio added,
  36  *  isa_read[wl] and isa_write[wl] fixed
  37  *  - Arnaldo Carvalho de Melo <acme@conectiva.com.br>
  38  */
  39
  40#define IO_SPACE_LIMIT 0xffff
  41
  42#define XQUAD_PORTIO_BASE 0xfe400000
  43#define XQUAD_PORTIO_QUAD 0x40000  /* 256k per quad. */
  44
  45#ifdef __KERNEL__
  46
  47#include <asm-generic/iomap.h>
  48
  49#include <linux/vmalloc.h>
  50
  51/*
  52 * Convert a virtual cached pointer to an uncached pointer
  53 */
  54#define xlate_dev_kmem_ptr(p)   p
  55
  56/**
  57 *      virt_to_phys    -       map virtual addresses to physical
  58 *      @address: address to remap
  59 *
  60 *      The returned physical address is the physical (CPU) mapping for
  61 *      the memory address given. It is only valid to use this function on
  62 *      addresses directly mapped or allocated via kmalloc.
  63 *
  64 *      This function does not give bus mappings for DMA transfers. In
  65 *      almost all conceivable cases a device driver should not be using
  66 *      this function
  67 */
  68
  69static inline unsigned long virt_to_phys(volatile void *address)
  70{
  71        return __pa(address);
  72}
  73
  74/**
  75 *      phys_to_virt    -       map physical address to virtual
  76 *      @address: address to remap
  77 *
  78 *      The returned virtual address is a current CPU mapping for
  79 *      the memory address given. It is only valid to use this function on
  80 *      addresses that have a kernel mapping
  81 *
  82 *      This function does not handle bus mappings for DMA transfers. In
  83 *      almost all conceivable cases a device driver should not be using
  84 *      this function
  85 */
  86
  87static inline void *phys_to_virt(unsigned long address)
  88{
  89        return __va(address);
  90}
  91
  92/*
  93 * Change "struct page" to physical address.
  94 */
  95#define page_to_phys(page)    ((dma_addr_t)page_to_pfn(page) << PAGE_SHIFT)
  96
  97/**
  98 * ioremap     -   map bus memory into CPU space
  99 * @offset:    bus address of the memory
 100 * @size:      size of the resource to map
 101 *
 102 * ioremap performs a platform specific sequence of operations to
 103 * make bus memory CPU accessible via the readb/readw/readl/writeb/
 104 * writew/writel functions and the other mmio helpers. The returned
 105 * address is not guaranteed to be usable directly as a virtual
 106 * address.
 107 *
 108 * If the area you are trying to map is a PCI BAR you should have a
 109 * look at pci_iomap().
 110 */
 111extern void __iomem *ioremap_nocache(resource_size_t offset, unsigned long size);
 112extern void __iomem *ioremap_cache(resource_size_t offset, unsigned long size);
 113
 114/*
 115 * The default ioremap() behavior is non-cached:
 116 */
 117static inline void __iomem *ioremap(resource_size_t offset, unsigned long size)
 118{
 119        return ioremap_nocache(offset, size);
 120}
 121
 122extern void iounmap(volatile void __iomem *addr);
 123
 124/*
 125 * early_ioremap() and early_iounmap() are for temporary early boot-time
 126 * mappings, before the real ioremap() is functional.
 127 * A boot-time mapping is currently limited to at most 16 pages.
 128 */
 129extern void early_ioremap_init(void);
 130extern void early_ioremap_clear(void);
 131extern void early_ioremap_reset(void);
 132extern void *early_ioremap(unsigned long offset, unsigned long size);
 133extern void early_iounmap(void *addr, unsigned long size);
 134extern void __iomem *fix_ioremap(unsigned idx, unsigned long phys);
 135
 136/*
 137 * ISA I/O bus memory addresses are 1:1 with the physical address.
 138 */
 139#define isa_virt_to_bus virt_to_phys
 140#define isa_page_to_bus page_to_phys
 141#define isa_bus_to_virt phys_to_virt
 142
 143/*
 144 * However PCI ones are not necessarily 1:1 and therefore these interfaces
 145 * are forbidden in portable PCI drivers.
 146 *
 147 * Allow them on x86 for legacy drivers, though.
 148 */
 149#define virt_to_bus virt_to_phys
 150#define bus_to_virt phys_to_virt
 151
 152/*
 153 * readX/writeX() are used to access memory mapped devices. On some
 154 * architectures the memory mapped IO stuff needs to be accessed
 155 * differently. On the x86 architecture, we just read/write the
 156 * memory location directly.
 157 */
 158
 159static inline unsigned char readb(const volatile void __iomem *addr)
 160{
 161        return *(volatile unsigned char __force *)addr;
 162}
 163
 164static inline unsigned short readw(const volatile void __iomem *addr)
 165{
 166        return *(volatile unsigned short __force *)addr;
 167}
 168
 169static inline unsigned int readl(const volatile void __iomem *addr)
 170{
 171        return *(volatile unsigned int __force *) addr;
 172}
 173
 174#define readb_relaxed(addr) readb(addr)
 175#define readw_relaxed(addr) readw(addr)
 176#define readl_relaxed(addr) readl(addr)
 177#define __raw_readb readb
 178#define __raw_readw readw
 179#define __raw_readl readl
 180
 181static inline void writeb(unsigned char b, volatile void __iomem *addr)
 182{
 183        *(volatile unsigned char __force *)addr = b;
 184}
 185
 186static inline void writew(unsigned short b, volatile void __iomem *addr)
 187{
 188        *(volatile unsigned short __force *)addr = b;
 189}
 190
 191static inline void writel(unsigned int b, volatile void __iomem *addr)
 192{
 193        *(volatile unsigned int __force *)addr = b;
 194}
 195#define __raw_writeb writeb
 196#define __raw_writew writew
 197#define __raw_writel writel
 198
 199#define mmiowb()
 200
 201static inline void
 202memset_io(volatile void __iomem *addr, unsigned char val, int count)
 203{
 204        memset((void __force *)addr, val, count);
 205}
 206
 207static inline void
 208memcpy_fromio(void *dst, const volatile void __iomem *src, int count)
 209{
 210        __memcpy(dst, (const void __force *)src, count);
 211}
 212
 213static inline void
 214memcpy_toio(volatile void __iomem *dst, const void *src, int count)
 215{
 216        __memcpy((void __force *)dst, src, count);
 217}
 218
 219/*
 220 * ISA space is 'always mapped' on a typical x86 system, no need to
 221 * explicitly ioremap() it. The fact that the ISA IO space is mapped
 222 * to PAGE_OFFSET is pure coincidence - it does not mean ISA values
 223 * are physical addresses. The following constant pointer can be
 224 * used as the IO-area pointer (it can be iounmapped as well, so the
 225 * analogy with PCI is quite large):
 226 */
 227#define __ISA_IO_base ((char __iomem *)(PAGE_OFFSET))
 228
 229/*
 230 *      Cache management
 231 *
 232 *      This needed for two cases
 233 *      1. Out of order aware processors
 234 *      2. Accidentally out of order processors (PPro errata #51)
 235 */
 236
 237#if defined(CONFIG_X86_OOSTORE) || defined(CONFIG_X86_PPRO_FENCE)
 238
 239static inline void flush_write_buffers(void)
 240{
 241        asm volatile("lock; addl $0,0(%%esp)": : :"memory");
 242}
 243
 244#else
 245
 246#define flush_write_buffers() do { } while (0)
 247
 248#endif
 249
 250#endif /* __KERNEL__ */
 251
 252extern void native_io_delay(void);
 253
 254extern int io_delay_type;
 255extern void io_delay_init(void);
 256
 257#if defined(CONFIG_PARAVIRT)
 258#include <asm/paravirt.h>
 259#else
 260
 261static inline void slow_down_io(void)
 262{
 263        native_io_delay();
 264#ifdef REALLY_SLOW_IO
 265        native_io_delay();
 266        native_io_delay();
 267        native_io_delay();
 268#endif
 269}
 270
 271#endif
 272
 273#define __BUILDIO(bwl, bw, type)                                \
 274static inline void out##bwl(unsigned type value, int port)      \
 275{                                                               \
 276        out##bwl##_local(value, port);                          \
 277}                                                               \
 278                                                                \
 279static inline unsigned type in##bwl(int port)                   \
 280{                                                               \
 281        return in##bwl##_local(port);                           \
 282}
 283
 284#define BUILDIO(bwl, bw, type)                                          \
 285static inline void out##bwl##_local(unsigned type value, int port)      \
 286{                                                                       \
 287        asm volatile("out" #bwl " %" #bw "0, %w1"               \
 288                     : : "a"(value), "Nd"(port));                       \
 289}                                                                       \
 290                                                                        \
 291static inline unsigned type in##bwl##_local(int port)                   \
 292{                                                                       \
 293        unsigned type value;                                            \
 294        asm volatile("in" #bwl " %w1, %" #bw "0"                \
 295                     : "=a"(value) : "Nd"(port));                       \
 296        return value;                                                   \
 297}                                                                       \
 298                                                                        \
 299static inline void out##bwl##_local_p(unsigned type value, int port)    \
 300{                                                                       \
 301        out##bwl##_local(value, port);                                  \
 302        slow_down_io();                                                 \
 303}                                                                       \
 304                                                                        \
 305static inline unsigned type in##bwl##_local_p(int port)                 \
 306{                                                                       \
 307        unsigned type value = in##bwl##_local(port);                    \
 308        slow_down_io();                                                 \
 309        return value;                                                   \
 310}                                                                       \
 311                                                                        \
 312__BUILDIO(bwl, bw, type)                                                \
 313                                                                        \
 314static inline void out##bwl##_p(unsigned type value, int port)          \
 315{                                                                       \
 316        out##bwl(value, port);                                          \
 317        slow_down_io();                                                 \
 318}                                                                       \
 319                                                                        \
 320static inline unsigned type in##bwl##_p(int port)                       \
 321{                                                                       \
 322        unsigned type value = in##bwl(port);                            \
 323        slow_down_io();                                                 \
 324        return value;                                                   \
 325}                                                                       \
 326                                                                        \
 327static inline void outs##bwl(int port, const void *addr, unsigned long count) \
 328{                                                                       \
 329        asm volatile("rep; outs" #bwl                                   \
 330                     : "+S"(addr), "+c"(count) : "d"(port));            \
 331}                                                                       \
 332                                                                        \
 333static inline void ins##bwl(int port, void *addr, unsigned long count)  \
 334{                                                                       \
 335        asm volatile("rep; ins" #bwl                                    \
 336                     : "+D"(addr), "+c"(count) : "d"(port));            \
 337}
 338
 339BUILDIO(b, b, char)
 340BUILDIO(w, w, short)
 341BUILDIO(l, , int)
 342
 343#endif
 344
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