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   *  isa_memset_io, isa_memcpy_fromio, isa_memcpy_toio added,
  33   *  isa_read[wl] and isa_write[wl] fixed
  34   *  - Arnaldo Carvalho de Melo <acme@conectiva.com.br>
  35   */
  36
  37 #ifdef SLOW_IO_BY_JUMPING
  38 #define __SLOW_DOWN_IO "\njmp 1f\n1:\tjmp 1f\n1:"
  39 #else
  40 #define __SLOW_DOWN_IO "\noutb %%al,$0x80"
  41 #endif
  42
  43 #ifdef REALLY_SLOW_IO
  44 #define __FULL_SLOW_DOWN_IO __SLOW_DOWN_IO __SLOW_DOWN_IO __SLOW_DOWN_IO __SLOW_DOWN_IO
  45 #else
  46 #define __FULL_SLOW_DOWN_IO __SLOW_DOWN_IO
  47 #endif
  48
  49 /*
  50  * Talk about misusing macros..
  51  */
  52 #define __OUT1(s,x) \
  53 extern inline void out##s(unsigned x value, unsigned short port) {
  54
  55 #define __OUT2(s,s1,s2) \
  56 __asm__ __volatile__ ("out" #s " %" s1 "0,%" s2 "1"
  57
  58 #define __OUT(s,s1,x) \
  59 __OUT1(s,x) __OUT2(s,s1,"w") : : "a" (value), "Nd" (port)); } \
  60 __OUT1(s##_p,x) __OUT2(s,s1,"w") __FULL_SLOW_DOWN_IO : : "a" (value), "Nd" (port));} \
  61
  62 #define __IN1(s) \
  63 extern inline RETURN_TYPE in##s(unsigned short port) { RETURN_TYPE _v;
  64
  65 #define __IN2(s,s1,s2) \
  66 __asm__ __volatile__ ("in" #s " %" s2 "1,%" s1 "0"
  67
  68 #define __IN(s,s1,i...) \
  69 __IN1(s) __IN2(s,s1,"w") : "=a" (_v) : "Nd" (port) ,##i ); return _v; } \
  70 __IN1(s##_p) __IN2(s,s1,"w") __FULL_SLOW_DOWN_IO : "=a" (_v) : "Nd" (port) ,##i ); return _v; } \
  71
  72 #define __INS(s) \
  73 extern inline void ins##s(unsigned short port, void * addr, unsigned long count) \
  74 { __asm__ __volatile__ ("rep ; ins" #s \
  75 : "=D" (addr), "=c" (count) : "d" (port),"0" (addr),"1" (count)); }
  76
  77 #define __OUTS(s) \
  78 extern inline void outs##s(unsigned short port, const void * addr, unsigned long count) \
  79 { __asm__ __volatile__ ("rep ; outs" #s \
  80 : "=S" (addr), "=c" (count) : "d" (port),"0" (addr),"1" (count)); }
  81
  82 #define RETURN_TYPE unsigned char
  83 __IN(b,"")
  84 #undef RETURN_TYPE
  85 #define RETURN_TYPE unsigned short
  86 __IN(w,"")
  87 #undef RETURN_TYPE
  88 #define RETURN_TYPE unsigned int
  89 __IN(l,"")
  90 #undef RETURN_TYPE
  91
  92 __OUT(b,"b",char)
  93 __OUT(w,"w",short)
  94 __OUT(l,,int)
  95
  96 __INS(b)
  97 __INS(w)
  98 __INS(l)
  99
 100 __OUTS(b)
 101 __OUTS(w)
 102 __OUTS(l)
 103
 104 #define IO_SPACE_LIMIT 0xffff
 105
 106 #ifdef __KERNEL__
 107
 108 #include <linux/vmalloc.h>
 109
 110 /*
 111  * Temporary debugging check to catch old code using
 112  * unmapped ISA addresses. Will be removed in 2.4.
 113  */
 114 #if 1
 115   extern void *__io_virt_debug(unsigned long x, const char *file, int line);
 116   extern unsigned long __io_phys_debug(unsigned long x, const char *file, int line);
 117   #define __io_virt(x) __io_virt_debug((unsigned long)(x), __FILE__, __LINE__)
 118 //#define __io_phys(x) __io_phys_debug((unsigned long)(x), __FILE__, __LINE__)
 119 #else
 120   #define __io_virt(x) ((void *)(x))
 121 //#define __io_phys(x) __pa(x)
 122 #endif
 123
 124 /*
 125  * Change virtual addresses to physical addresses and vv.
 126  * These are pretty trivial
 127  */
 128 extern inline unsigned long virt_to_phys(volatile void * address)
 129 {
 130         return __pa(address);
 131 }
 132
 133 extern inline void * phys_to_virt(unsigned long address)
 134 {
 135         return __va(address);
 136 }
 137
 138 extern void * __ioremap(unsigned long offset, unsigned long size, unsigned long flags);
 139
 140 extern inline void * ioremap (unsigned long offset, unsigned long size)
 141 {
 142         return __ioremap(offset, size, 0);
 143 }
 144
 145 /*
 146  * This one maps high address device memory and turns off caching for that area.
 147  * it's useful if some control registers are in such an area and write combining
 148  * or read caching is not desirable:
 149  */
 150 extern inline void * ioremap_nocache (unsigned long offset, unsigned long size)
 151 {
 152         return __ioremap(offset, size, _PAGE_PCD);
 153 }
 154
 155 extern void iounmap(void *addr);
 156
 157 /*
 158  * IO bus memory addresses are also 1:1 with the physical address
 159  */
 160 #define virt_to_bus virt_to_phys
 161 #define bus_to_virt phys_to_virt
 162
 163 /*
 164  * readX/writeX() are used to access memory mapped devices. On some
 165  * architectures the memory mapped IO stuff needs to be accessed
 166  * differently. On the x86 architecture, we just read/write the
 167  * memory location directly.
 168  */
 169
 170 #define readb(addr) (*(volatile unsigned char *) __io_virt(addr))
 171 #define readw(addr) (*(volatile unsigned short *) __io_virt(addr))
 172 #define readl(addr) (*(volatile unsigned int *) __io_virt(addr))
 173 #define __raw_readb readb
 174 #define __raw_readw readw
 175 #define __raw_readl readl
 176
 177 #define writeb(b,addr) (*(volatile unsigned char *) __io_virt(addr) = (b))
 178 #define writew(b,addr) (*(volatile unsigned short *) __io_virt(addr) = (b))
 179 #define writel(b,addr) (*(volatile unsigned int *) __io_virt(addr) = (b))
 180 #define __raw_writeb writeb
 181 #define __raw_writew writew
 182 #define __raw_writel writel
 183
 184 #define memset_io(a,b,c)        memset(__io_virt(a),(b),(c))
 185 #define memcpy_fromio(a,b,c)    memcpy((a),__io_virt(b),(c))
 186 #define memcpy_toio(a,b,c)      memcpy(__io_virt(a),(b),(c))
 187
 188 /*
 189  * ISA space is 'always mapped' on a typical x86 system, no need to
 190  * explicitly ioremap() it. The fact that the ISA IO space is mapped
 191  * to PAGE_OFFSET is pure coincidence - it does not mean ISA values
 192  * are physical addresses. The following constant pointer can be
 193  * used as the IO-area pointer (it can be iounmapped as well, so the
 194  * analogy with PCI is quite large):
 195  */
 196 #define __ISA_IO_base ((char *)(PAGE_OFFSET))
 197
 198 #define isa_readb(a) readb(__ISA_IO_base + (a))
 199 #define isa_readw(a) readw(__ISA_IO_base + (a))
 200 #define isa_readl(a) readl(__ISA_IO_base + (a))
 201 #define isa_writeb(b,a) writeb(b,__ISA_IO_base + (a))
 202 #define isa_writew(w,a) writew(w,__ISA_IO_base + (a))
 203 #define isa_writel(l,a) writel(l,__ISA_IO_base + (a))
 204 #define isa_memset_io(a,b,c)            memset_io(__ISA_IO_base + (a),(b),(c))
 205 #define isa_memcpy_fromio(a,b,c)        memcpy_fromio((a),__ISA_IO_base + (b),(c))
 206 #define isa_memcpy_toio(a,b,c)          memcpy_toio(__ISA_IO_base + (a),(b),(c))
 207
 208
 209 /*
 210  * Again, i386 does not require mem IO specific function.
 211  */
 212
 213 #define eth_io_copy_and_sum(a,b,c,d)            eth_copy_and_sum((a),__io_virt(b),(c),(d))
 214 #define isa_eth_io_copy_and_sum(a,b,c,d)        eth_copy_and_sum((a),__io_virt(__ISA_IO_base + (b)),(c),(d))
 215
 216 static inline int check_signature(unsigned long io_addr,
 217         const unsigned char *signature, int length)
 218 {
 219         int retval = 0;
 220         do {
 221                 if (readb(io_addr) != *signature)
 222                         goto out;
 223                 io_addr++;
 224                 signature++;
 225                 length--;
 226         } while (length);
 227         retval = 1;
 228 out:
 229         return retval;
 230 }
 231
 232 static inline int isa_check_signature(unsigned long io_addr,
 233         const unsigned char *signature, int length)
 234 {
 235         int retval = 0;
 236         do {
 237                 if (isa_readb(io_addr) != *signature)
 238                         goto out;
 239                 io_addr++;
 240                 signature++;
 241                 length--;
 242         } while (length);
 243         retval = 1;
 244 out:
 245         return retval;
 246 }
 247
 248 /* Nothing to do */
 249
 250 #define dma_cache_inv(_start,_size)             do { } while (0)
 251 #define dma_cache_wback(_start,_size)           do { } while (0)
 252 #define dma_cache_wback_inv(_start,_size)       do { } while (0)
 253
 254 #endif /* __KERNEL__ */
 255
 256 #endif