i386/linux/linux-2.3.21/include/asm-i386/io.h

   1 #ifndef _ASM_IO_H
   2 #define _ASM_IO_H
   3
   4 /*
   5  * This file contains the definitions for the x86 IO instructions
   6  * inb/inw/inl/outb/outw/outl and the "string versions" of the same
   7  * (insb/insw/insl/outsb/outsw/outsl). You can also use "pausing"
   8  * versions of the single-IO instructions (inb_p/inw_p/..).
   9  *
  10  * This file is not meant to be obfuscating: it's just complicated
  11  * to (a) handle it all in a way that makes gcc able to optimize it
  12  * as well as possible and (b) trying to avoid writing the same thing
  13  * over and over again with slight variations and possibly making a
  14  * mistake somewhere.
  15  */
  16
  17 /*
  18  * Thanks to James van Artsdalen for a better timing-fix than
  19  * the two short jumps: using outb's to a nonexistent port seems
  20  * to guarantee better timings even on fast machines.
  21  *
  22  * On the other hand, I'd like to be sure of a non-existent port:
  23  * I feel a bit unsafe about using 0x80 (should be safe, though)
  24  *
  25  *              Linus
  26  */
  27
  28  /*
  29   *  Bit simplified and optimized by Jan Hubicka
  30   *  Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999.
  31   */
  32
  33 #ifdef SLOW_IO_BY_JUMPING
  34 #define __SLOW_DOWN_IO "\njmp 1f\n1:\tjmp 1f\n1:"
  35 #else
  36 #define __SLOW_DOWN_IO "\noutb %%al,$0x80"
  37 #endif
  38
  39 #ifdef REALLY_SLOW_IO
  40 #define __FULL_SLOW_DOWN_IO __SLOW_DOWN_IO __SLOW_DOWN_IO __SLOW_DOWN_IO __SLOW_DOWN_IO
  41 #else
  42 #define __FULL_SLOW_DOWN_IO __SLOW_DOWN_IO
  43 #endif
  44
  45 /*
  46  * Talk about misusing macros..
  47  */
  48 #define __OUT1(s,x) \
  49 extern inline void out##s(unsigned x value, unsigned short port) {
  50
  51 #define __OUT2(s,s1,s2) \
  52 __asm__ __volatile__ ("out" #s " %" s1 "0,%" s2 "1"
  53
  54 #define __OUT(s,s1,x) \
  55 __OUT1(s,x) __OUT2(s,s1,"w") : : "a" (value), "Nd" (port)); } \
  56 __OUT1(s##_p,x) __OUT2(s,s1,"w") __FULL_SLOW_DOWN_IO : : "a" (value), "Nd" (port));} \
  57
  58 #define __IN1(s) \
  59 extern inline RETURN_TYPE in##s(unsigned short port) { RETURN_TYPE _v;
  60
  61 #define __IN2(s,s1,s2) \
  62 __asm__ __volatile__ ("in" #s " %" s2 "1,%" s1 "0"
  63
  64 #define __IN(s,s1,i...) \
  65 __IN1(s) __IN2(s,s1,"w") : "=a" (_v) : "Nd" (port) ,##i ); return _v; } \
  66 __IN1(s##_p) __IN2(s,s1,"w") __FULL_SLOW_DOWN_IO : "=a" (_v) : "Nd" (port) ,##i ); return _v; } \
  67
  68 #define __INS(s) \
  69 extern inline void ins##s(unsigned short port, void * addr, unsigned long count) \
  70 { __asm__ __volatile__ ("cld ; rep ; ins" #s \
  71 : "=D" (addr), "=c" (count) : "d" (port),"0" (addr),"1" (count)); }
  72
  73 #define __OUTS(s) \
  74 extern inline void outs##s(unsigned short port, const void * addr, unsigned long count) \
  75 { __asm__ __volatile__ ("cld ; rep ; outs" #s \
  76 : "=S" (addr), "=c" (count) : "d" (port),"0" (addr),"1" (count)); }
  77
  78 #define RETURN_TYPE unsigned char
  79 __IN(b,"")
  80 #undef RETURN_TYPE
  81 #define RETURN_TYPE unsigned short
  82 __IN(w,"")
  83 #undef RETURN_TYPE
  84 #define RETURN_TYPE unsigned int
  85 __IN(l,"")
  86 #undef RETURN_TYPE
  87
  88 __OUT(b,"b",char)
  89 __OUT(w,"w",short)
  90 __OUT(l,,int)
  91
  92 __INS(b)
  93 __INS(w)
  94 __INS(l)
  95
  96 __OUTS(b)
  97 __OUTS(w)
  98 __OUTS(l)
  99
 100 #ifdef __KERNEL__
 101
 102 #include <linux/config.h>
 103 #include <linux/vmalloc.h>
 104 #include <asm/page.h>
 105
 106 #define __io_virt(x)            ((void *)(PAGE_OFFSET | (unsigned long)(x)))
 107 #define __io_phys(x)            ((unsigned long)(x) & ~PAGE_OFFSET)
 108 /*
 109  * Change virtual addresses to physical addresses and vv.
 110  * These are pretty trivial
 111  */
 112 extern inline unsigned long virt_to_phys(volatile void * address)
 113 {
 114 #ifdef CONFIG_BIGMEM
 115         return __pa(address);
 116 #else
 117         return __io_phys(address);
 118 #endif
 119 }
 120
 121 extern inline void * phys_to_virt(unsigned long address)
 122 {
 123 #ifdef CONFIG_BIGMEM
 124         return __va(address);
 125 #else
 126         return __io_virt(address);
 127 #endif
 128 }
 129
 130 extern void * __ioremap(unsigned long offset, unsigned long size, unsigned long flags);
 131
 132 extern inline void * ioremap (unsigned long offset, unsigned long size)
 133 {
 134         return __ioremap(offset, size, 0);
 135 }
 136
 137 /*
 138  * This one maps high address device memory and turns off caching for that area.
 139  * it's useful if some control registers are in such an area and write combining
 140  * or read caching is not desirable:
 141  */
 142 extern inline void * ioremap_nocache (unsigned long offset, unsigned long size)
 143 {
 144         return __ioremap(offset, size, _PAGE_PCD);
 145 }
 146
 147 extern void iounmap(void *addr);
 148
 149 /*
 150  * IO bus memory addresses are also 1:1 with the physical address
 151  */
 152 #define virt_to_bus virt_to_phys
 153 #define bus_to_virt phys_to_virt
 154
 155 /*
 156  * readX/writeX() are used to access memory mapped devices. On some
 157  * architectures the memory mapped IO stuff needs to be accessed
 158  * differently. On the x86 architecture, we just read/write the
 159  * memory location directly.
 160  */
 161
 162 #define readb(addr) (*(volatile unsigned char *) __io_virt(addr))
 163 #define readw(addr) (*(volatile unsigned short *) __io_virt(addr))
 164 #define readl(addr) (*(volatile unsigned int *) __io_virt(addr))
 165 #define __raw_readb readb
 166 #define __raw_readw readw
 167 #define __raw_readl readl
 168
 169 #define writeb(b,addr) (*(volatile unsigned char *) __io_virt(addr) = (b))
 170 #define writew(b,addr) (*(volatile unsigned short *) __io_virt(addr) = (b))
 171 #define writel(b,addr) (*(volatile unsigned int *) __io_virt(addr) = (b))
 172 #define __raw_writeb writeb
 173 #define __raw_writew writew
 174 #define __raw_writel writel
 175
 176 #define memset_io(a,b,c)        memset(__io_virt(a),(b),(c))
 177 #define memcpy_fromio(a,b,c)    memcpy((a),__io_virt(b),(c))
 178 #define memcpy_toio(a,b,c)      memcpy(__io_virt(a),(b),(c))
 179
 180 /*
 181  * Again, i386 does not require mem IO specific function.
 182  */
 183
 184 #define eth_io_copy_and_sum(a,b,c,d)    eth_copy_and_sum((a),__io_virt(b),(c),(d))
 185
 186 static inline int check_signature(unsigned long io_addr,
 187         const unsigned char *signature, int length)
 188 {
 189         int retval = 0;
 190         do {
 191                 if (readb(io_addr) != *signature)
 192                         goto out;
 193                 io_addr++;
 194                 signature++;
 195                 length--;
 196         } while (length);
 197         retval = 1;
 198 out:
 199         return retval;
 200 }
 201
 202 /* Nothing to do */
 203
 204 #define dma_cache_inv(_start,_size)             do { } while (0)
 205 #define dma_cache_wback(_start,_size)           do { } while (0)
 206 #define dma_cache_wback_inv(_start,_size)       do { } while (0)
 207
 208 #endif /* __KERNEL__ */
 209
 210 #endif