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 #define IO_SPACE_LIMIT 0xffff 38 39 #include <asm/types.h> 40 41 42 #ifdef __KERNEL__ 43 44 45 /* 46 * readX/writeX() are used to access memory mapped devices. On some 47 * architectures the memory mapped IO stuff needs to be accessed 48 * differently. On the x86 architecture, we just read/write the 49 * memory location directly. 50 */ 51 52 #define readb(addr) (*(volatile unsigned char *) (addr)) 53 #define readw(addr) (*(volatile unsigned short *) (addr)) 54 #define readl(addr) (*(volatile unsigned int *) (addr)) 55 #define __raw_readb readb 56 #define __raw_readw readw 57 #define __raw_readl readl 58 59 #define writeb(b,addr) (*(volatile unsigned char *) (addr) = (b)) 60 #define writew(b,addr) (*(volatile unsigned short *) (addr) = (b)) 61 #define writel(b,addr) (*(volatile unsigned int *) (addr) = (b)) 62 #define __raw_writeb writeb 63 #define __raw_writew writew 64 #define __raw_writel writel 65 66 #define memset_io(a,b,c) memset((a),(b),(c)) 67 #define memcpy_fromio(a,b,c) memcpy((a),(b),(c)) 68 #define memcpy_toio(a,b,c) memcpy((a),(b),(c)) 69 70 /* 71 * ISA space is 'always mapped' on a typical x86 system, no need to 72 * explicitly ioremap() it. The fact that the ISA IO space is mapped 73 * to PAGE_OFFSET is pure coincidence - it does not mean ISA values 74 * are physical addresses. The following constant pointer can be 75 * used as the IO-area pointer (it can be iounmapped as well, so the 76 * analogy with PCI is quite large): 77 */ 78 #define isa_readb(a) readb((a)) 79 #define isa_readw(a) readw((a)) 80 #define isa_readl(a) readl((a)) 81 #define isa_writeb(b,a) writeb(b,(a)) 82 #define isa_writew(w,a) writew(w,(a)) 83 #define isa_writel(l,a) writel(l,(a)) 84 #define isa_memset_io(a,b,c) memset_io((a),(b),(c)) 85 #define isa_memcpy_fromio(a,b,c) memcpy_fromio((a),(b),(c)) 86 #define isa_memcpy_toio(a,b,c) memcpy_toio((a),(b),(c)) 87 88 89 static inline int check_signature(unsigned long io_addr, 90 const unsigned char *signature, int length) 91 { 92 int retval = 0; 93 do { 94 if (readb(io_addr) != *signature) 95 goto out; 96 io_addr++; 97 signature++; 98 length--; 99 } while (length); 100 retval = 1; 101 out: 102 return retval; 103 } 104 105 /** 106 * isa_check_signature - find BIOS signatures 107 * @io_addr: mmio address to check 108 * @signature: signature block 109 * @length: length of signature 110 * 111 * Perform a signature comparison with the ISA mmio address io_addr. 112 * Returns 1 on a match. 113 * 114 * This function is deprecated. New drivers should use ioremap and 115 * check_signature. 116 */ 117 118 119 static inline int isa_check_signature(unsigned long io_addr, 120 const unsigned char *signature, int length) 121 { 122 int retval = 0; 123 do { 124 if (isa_readb(io_addr) != *signature) 125 goto out; 126 io_addr++; 127 signature++; 128 length--; 129 } while (length); 130 retval = 1; 131 out: 132 return retval; 133 } 134 135 #endif /* __KERNEL__ */ 136 137 #ifdef SLOW_IO_BY_JUMPING 138 #define __SLOW_DOWN_IO "\njmp 1f\n1:\tjmp 1f\n1:" 139 #else 140 #define __SLOW_DOWN_IO "\noutb %%al,$0xed" 141 #endif 142 143 #ifdef REALLY_SLOW_IO 144 #define __FULL_SLOW_DOWN_IO __SLOW_DOWN_IO __SLOW_DOWN_IO __SLOW_DOWN_IO __SLOW_DOWN_IO 145 #else 146 #define __FULL_SLOW_DOWN_IO __SLOW_DOWN_IO 147 #endif 148 149 150 /* 151 * Talk about misusing macros.. 152 */ 153 #define __OUT1(s,x) \ 154 static inline void out##s(unsigned x value, unsigned short port) { 155 156 #define __OUT2(s,s1,s2) \ 157 __asm__ __volatile__ ("out" #s " %" s1 "0,%" s2 "1" 158 159 160 #define __OUT(s,s1,x) \ 161 __OUT1(s,x) __OUT2(s,s1,"w") : : "a" (value), "Nd" (port)); } \ 162 __OUT1(s##_p,x) __OUT2(s,s1,"w") __FULL_SLOW_DOWN_IO : : "a" (value), "Nd" (port));} 163 164 #define __IN1(s) \ 165 static inline RETURN_TYPE in##s(unsigned short port) { RETURN_TYPE _v; 166 167 #define __IN2(s,s1,s2) \ 168 __asm__ __volatile__ ("in" #s " %" s2 "1,%" s1 "0" 169 170 #define __IN(s,s1,i...) \ 171 __IN1(s) __IN2(s,s1,"w") : "=a" (_v) : "Nd" (port) ,##i ); return _v; } \ 172 __IN1(s##_p) __IN2(s,s1,"w") __FULL_SLOW_DOWN_IO : "=a" (_v) : "Nd" (port) ,##i ); return _v; } 173 174 #define __INS(s) \ 175 static inline void ins##s(unsigned short port, void * addr, unsigned long count) \ 176 { __asm__ __volatile__ ("rep ; ins" #s \ 177 : "=D" (addr), "=c" (count) : "d" (port),"0" (addr),"1" (count)); } 178 179 #define __OUTS(s) \ 180 static inline void outs##s(unsigned short port, const void * addr, unsigned long count) \ 181 { __asm__ __volatile__ ("rep ; outs" #s \ 182 : "=S" (addr), "=c" (count) : "d" (port),"0" (addr),"1" (count)); } 183 184 #define RETURN_TYPE unsigned char 185 __IN(b,"") 186 #undef RETURN_TYPE 187 #define RETURN_TYPE unsigned short 188 __IN(w,"") 189 #undef RETURN_TYPE 190 #define RETURN_TYPE unsigned int 191 __IN(l,"") 192 #undef RETURN_TYPE 193 194 __OUT(b,"b",char) 195 __OUT(w,"w",short) 196 __OUT(l,,int) 197 198 __INS(b) 199 __INS(w) 200 __INS(l) 201 202 __OUTS(b) 203 __OUTS(w) 204 __OUTS(l) 205 206 static inline void sync(void) 207 { 208 } 209 210 /* 211 * Given a physical address and a length, return a virtual address 212 * that can be used to access the memory range with the caching 213 * properties specified by "flags". 214 */ 215 #define MAP_NOCACHE (0) 216 #define MAP_WRCOMBINE (0) 217 #define MAP_WRBACK (0) 218 #define MAP_WRTHROUGH (0) 219 220 static inline void * 221 map_physmem(phys_addr_t paddr, unsigned long len, unsigned long flags) 222 { 223 return (void *)paddr; 224 } 225 226 /* 227 * Take down a mapping set up by map_physmem(). 228 */ 229 static inline void unmap_physmem(void *vaddr, unsigned long flags) 230 { 231 232 } 233 234 static inline phys_addr_t virt_to_phys(void * vaddr) 235 { 236 return (phys_addr_t)(vaddr); 237 } 238 239 /* 240 * TODO: The kernel offers some more advanced versions of barriers, it might 241 * have some advantages to use them instead of the simple one here. 242 */ 243 #define dmb() __asm__ __volatile__ ("" : : : "memory") 244 #define __iormb() dmb() 245 #define __iowmb() dmb() 246 247 #endif 248