arch/x86/include/asm/io_64.h

   1 #ifndef _ASM_X86_IO_64_H
   2 #define _ASM_X86_IO_64_H
   3
   4
   5 /*
   6  * This file contains the definitions for the x86 IO instructions
   7  * inb/inw/inl/outb/outw/outl and the "string versions" of the same
   8  * (insb/insw/insl/outsb/outsw/outsl). You can also use "pausing"
   9  * versions of the single-IO instructions (inb_p/inw_p/..).
  10  *
  11  * This file is not meant to be obfuscating: it's just complicated
  12  * to (a) handle it all in a way that makes gcc able to optimize it
  13  * as well as possible and (b) trying to avoid writing the same thing
  14  * over and over again with slight variations and possibly making a
  15  * mistake somewhere.
  16  */
  17
  18 /*
  19  * Thanks to James van Artsdalen for a better timing-fix than
  20  * the two short jumps: using outb's to a nonexistent port seems
  21  * to guarantee better timings even on fast machines.
  22  *
  23  * On the other hand, I'd like to be sure of a non-existent port:
  24  * I feel a bit unsafe about using 0x80 (should be safe, though)
  25  *
  26  *              Linus
  27  */
  28
  29  /*
  30   *  Bit simplified and optimized by Jan Hubicka
  31   *  Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999.
  32   *
  33   *  isa_memset_io, isa_memcpy_fromio, isa_memcpy_toio added,
  34   *  isa_read[wl] and isa_write[wl] fixed
  35   *  - Arnaldo Carvalho de Melo <acme@conectiva.com.br>
  36   */
  37
  38 #ifdef __KERNEL__
  39
  40 #include <asm-generic/iomap.h>
  41
  42 #include <linux/vmalloc.h>
  43
  44 /*
  45  * Convert a virtual cached pointer to an uncached pointer
  46  */
  47 #define xlate_dev_kmem_ptr(p)   p
  48
  49 void memset_io(volatile void __iomem *a, int b, size_t c);
  50
  51 void __memcpy_fromio(void *, unsigned long, unsigned);
  52 static inline void memcpy_fromio(void *to, const volatile void __iomem *from,
  53                                  unsigned len)
  54 {
  55         __memcpy_fromio(to, (unsigned long)from, len);
  56 }
  57
  58 void __memcpy_toio(unsigned long, const void *, unsigned);
  59 static inline void memcpy_toio(volatile void __iomem *to, const void *from,
  60                                unsigned len)
  61 {
  62         __memcpy_toio((unsigned long)to, from, len);
  63 }
  64
  65 /*
  66  * ISA space is 'always mapped' on a typical x86 system, no need to
  67  * explicitly ioremap() it. The fact that the ISA IO space is mapped
  68  * to PAGE_OFFSET is pure coincidence - it does not mean ISA values
  69  * are physical addresses. The following constant pointer can be
  70  * used as the IO-area pointer (it can be iounmapped as well, so the
  71  * analogy with PCI is quite large):
  72  */
  73 #define __ISA_IO_base ((char __iomem *)(PAGE_OFFSET))
  74
  75 /*
  76  *      Cache management
  77  *
  78  *      This needed for two cases
  79  *      1. Out of order aware processors
  80  *      2. Accidentally out of order processors (PPro errata #51)
  81  */
  82 #define flush_write_buffers() do { } while (0)
  83
  84 #endif /* __KERNEL__ */
  85
  86 extern void native_io_delay(void);
  87
  88 extern int io_delay_type;
  89 extern void io_delay_init(void);
  90
  91 #if defined(CONFIG_PARAVIRT)
  92 #include <asm/paravirt.h>
  93 #else
  94
  95 static inline void slow_down_io(void)
  96 {
  97         native_io_delay();
  98 #ifdef REALLY_SLOW_IO
  99         native_io_delay();
 100         native_io_delay();
 101         native_io_delay();
 102 #endif
 103 }
 104
 105 #endif
 106
 107 #define BUILDIO(bwl, bw, type)                                          \
 108 static inline void out##bwl(unsigned type value, int port)              \
 109 {                                                                       \
 110         asm volatile("out" #bwl " %" #bw "0, %w1"                       \
 111                      : : "a"(value), "Nd"(port));                       \
 112 }                                                                       \
 113                                                                         \
 114 static inline unsigned type in##bwl(int port)                           \
 115 {                                                                       \
 116         unsigned type value;                                            \
 117         asm volatile("in" #bwl " %w1, %" #bw "0"                        \
 118                      : "=a"(value) : "Nd"(port));                       \
 119         return value;                                                   \
 120 }                                                                       \
 121                                                                         \
 122 static inline void out##bwl##_p(unsigned type value, int port)          \
 123 {                                                                       \
 124         out##bwl(value, port);                                          \
 125         slow_down_io();                                                 \
 126 }                                                                       \
 127                                                                         \
 128 static inline unsigned type in##bwl##_p(int port)                       \
 129 {                                                                       \
 130         unsigned type value = in##bwl(port);                            \
 131         slow_down_io();                                                 \
 132         return value;                                                   \
 133 }                                                                       \
 134                                                                         \
 135 static inline void outs##bwl(int port, const void *addr, unsigned long count) \
 136 {                                                                       \
 137         asm volatile("rep; outs" #bwl                                   \
 138                      : "+S"(addr), "+c"(count) : "d"(port));            \
 139 }                                                                       \
 140                                                                         \
 141 static inline void ins##bwl(int port, void *addr, unsigned long count)  \
 142 {                                                                       \
 143         asm volatile("rep; ins" #bwl                                    \
 144                      : "+D"(addr), "+c"(count) : "d"(port));            \
 145 }
 146
 147 BUILDIO(b, b, char)
 148 BUILDIO(w, w, short)
 149 BUILDIO(l, , int)
 150
 151 #endif /* _ASM_X86_IO_64_H */