include/asm-i386/io.h

   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 physical pointer to a virtual kernel pointer for /dev/mem
  53  * access
  54  */
  55 #define xlate_dev_mem_ptr(p)    __va(p)
  56
  57 /*
  58  * Convert a virtual cached pointer to an uncached pointer
  59  */
  60 #define xlate_dev_kmem_ptr(p)   p
  61
  62 /**
  63  *      virt_to_phys    -       map virtual addresses to physical
  64  *      @address: address to remap
  65  *
  66  *      The returned physical address is the physical (CPU) mapping for
  67  *      the memory address given. It is only valid to use this function on
  68  *      addresses directly mapped or allocated via kmalloc.
  69  *
  70  *      This function does not give bus mappings for DMA transfers. In
  71  *      almost all conceivable cases a device driver should not be using
  72  *      this function
  73  */
  74
  75 static inline unsigned long virt_to_phys(volatile void * address)
  76 {
  77         return __pa(address);
  78 }
  79
  80 /**
  81  *      phys_to_virt    -       map physical address to virtual
  82  *      @address: address to remap
  83  *
  84  *      The returned virtual address is a current CPU mapping for
  85  *      the memory address given. It is only valid to use this function on
  86  *      addresses that have a kernel mapping
  87  *
  88  *      This function does not handle bus mappings for DMA transfers. In
  89  *      almost all conceivable cases a device driver should not be using
  90  *      this function
  91  */
  92
  93 static inline void * phys_to_virt(unsigned long address)
  94 {
  95         return __va(address);
  96 }
  97
  98 /*
  99  * Change "struct page" to physical address.
 100  */
 101 #define page_to_phys(page)    ((dma_addr_t)page_to_pfn(page) << PAGE_SHIFT)
 102
 103 extern void __iomem * __ioremap(unsigned long offset, unsigned long size, unsigned long flags);
 104
 105 /**
 106  * ioremap     -   map bus memory into CPU space
 107  * @offset:    bus address of the memory
 108  * @size:      size of the resource to map
 109  *
 110  * ioremap performs a platform specific sequence of operations to
 111  * make bus memory CPU accessible via the readb/readw/readl/writeb/
 112  * writew/writel functions and the other mmio helpers. The returned
 113  * address is not guaranteed to be usable directly as a virtual
 114  * address.
 115  */
 116
 117 static inline void __iomem * ioremap(unsigned long offset, unsigned long size)
 118 {
 119         return __ioremap(offset, size, 0);
 120 }
 121
 122 extern void __iomem * ioremap_nocache(unsigned long offset, unsigned long size);
 123 extern void iounmap(volatile void __iomem *addr);
 124
 125 /*
 126  * bt_ioremap() and bt_iounmap() are for temporary early boot-time
 127  * mappings, before the real ioremap() is functional.
 128  * A boot-time mapping is currently limited to at most 16 pages.
 129  */
 130 extern void *bt_ioremap(unsigned long offset, unsigned long size);
 131 extern void bt_iounmap(void *addr, unsigned long size);
 132
 133 /* Use early IO mappings for DMI because it's initialized early */
 134 #define dmi_ioremap bt_ioremap
 135 #define dmi_iounmap bt_iounmap
 136 #define dmi_alloc alloc_bootmem
 137
 138 /*
 139  * ISA I/O bus memory addresses are 1:1 with the physical address.
 140  */
 141 #define isa_virt_to_bus virt_to_phys
 142 #define isa_page_to_bus page_to_phys
 143 #define isa_bus_to_virt phys_to_virt
 144
 145 /*
 146  * However PCI ones are not necessarily 1:1 and therefore these interfaces
 147  * are forbidden in portable PCI drivers.
 148  *
 149  * Allow them on x86 for legacy drivers, though.
 150  */
 151 #define virt_to_bus virt_to_phys
 152 #define bus_to_virt phys_to_virt
 153
 154 /*
 155  * readX/writeX() are used to access memory mapped devices. On some
 156  * architectures the memory mapped IO stuff needs to be accessed
 157  * differently. On the x86 architecture, we just read/write the
 158  * memory location directly.
 159  */
 160
 161 static inline unsigned char readb(const volatile void __iomem *addr)
 162 {
 163         return *(volatile unsigned char __force *) addr;
 164 }
 165 static inline unsigned short readw(const volatile void __iomem *addr)
 166 {
 167         return *(volatile unsigned short __force *) addr;
 168 }
 169 static inline unsigned int readl(const volatile void __iomem *addr)
 170 {
 171         return *(volatile unsigned int __force *) addr;
 172 }
 173 #define readb_relaxed(addr) readb(addr)
 174 #define readw_relaxed(addr) readw(addr)
 175 #define readl_relaxed(addr) readl(addr)
 176 #define __raw_readb readb
 177 #define __raw_readw readw
 178 #define __raw_readl readl
 179
 180 static inline void writeb(unsigned char b, volatile void __iomem *addr)
 181 {
 182         *(volatile unsigned char __force *) addr = b;
 183 }
 184 static inline void writew(unsigned short b, volatile void __iomem *addr)
 185 {
 186         *(volatile unsigned short __force *) addr = b;
 187 }
 188 static inline void writel(unsigned int b, volatile void __iomem *addr)
 189 {
 190         *(volatile unsigned int __force *) addr = b;
 191 }
 192 #define __raw_writeb writeb
 193 #define __raw_writew writew
 194 #define __raw_writel writel
 195
 196 #define mmiowb()
 197
 198 static inline void memset_io(volatile void __iomem *addr, unsigned char val, int count)
 199 {
 200         memset((void __force *) addr, val, count);
 201 }
 202 static inline void memcpy_fromio(void *dst, const volatile void __iomem *src, int count)
 203 {
 204         __memcpy(dst, (void __force *) src, count);
 205 }
 206 static inline void memcpy_toio(volatile void __iomem *dst, const void *src, int count)
 207 {
 208         __memcpy((void __force *) dst, src, count);
 209 }
 210
 211 /*
 212  * ISA space is 'always mapped' on a typical x86 system, no need to
 213  * explicitly ioremap() it. The fact that the ISA IO space is mapped
 214  * to PAGE_OFFSET is pure coincidence - it does not mean ISA values
 215  * are physical addresses. The following constant pointer can be
 216  * used as the IO-area pointer (it can be iounmapped as well, so the
 217  * analogy with PCI is quite large):
 218  */
 219 #define __ISA_IO_base ((char __iomem *)(PAGE_OFFSET))
 220
 221 /*
 222  *      Cache management
 223  *
 224  *      This needed for two cases
 225  *      1. Out of order aware processors
 226  *      2. Accidentally out of order processors (PPro errata #51)
 227  */
 228
 229 #if defined(CONFIG_X86_OOSTORE) || defined(CONFIG_X86_PPRO_FENCE)
 230
 231 static inline void flush_write_buffers(void)
 232 {
 233         __asm__ __volatile__ ("lock; addl $0,0(%%esp)": : :"memory");
 234 }
 235
 236 #define dma_cache_inv(_start,_size)             flush_write_buffers()
 237 #define dma_cache_wback(_start,_size)           flush_write_buffers()
 238 #define dma_cache_wback_inv(_start,_size)       flush_write_buffers()
 239
 240 #else
 241
 242 /* Nothing to do */
 243
 244 #define dma_cache_inv(_start,_size)             do { } while (0)
 245 #define dma_cache_wback(_start,_size)           do { } while (0)
 246 #define dma_cache_wback_inv(_start,_size)       do { } while (0)
 247 #define flush_write_buffers()
 248
 249 #endif
 250
 251 #endif /* __KERNEL__ */
 252
 253 #if defined(CONFIG_PARAVIRT)
 254 #include <asm/paravirt.h>
 255 #else
 256
 257 #define __SLOW_DOWN_IO "outb %%al,$0x80;"
 258
 259 static inline void slow_down_io(void) {
 260         __asm__ __volatile__(
 261                 __SLOW_DOWN_IO
 262 #ifdef REALLY_SLOW_IO
 263                 __SLOW_DOWN_IO __SLOW_DOWN_IO __SLOW_DOWN_IO
 264 #endif
 265                 : : );
 266 }
 267
 268 #endif
 269
 270 #ifdef CONFIG_X86_NUMAQ
 271 extern void *xquad_portio;    /* Where the IO area was mapped */
 272 #define XQUAD_PORT_ADDR(port, quad) (xquad_portio + (XQUAD_PORTIO_QUAD*quad) + port)
 273 #define __BUILDIO(bwl,bw,type) \
 274 static inline void out##bwl##_quad(unsigned type value, int port, int quad) { \
 275         if (xquad_portio) \
 276                 write##bwl(value, XQUAD_PORT_ADDR(port, quad)); \
 277         else \
 278                 out##bwl##_local(value, port); \
 279 } \
 280 static inline void out##bwl(unsigned type value, int port) { \
 281         out##bwl##_quad(value, port, 0); \
 282 } \
 283 static inline unsigned type in##bwl##_quad(int port, int quad) { \
 284         if (xquad_portio) \
 285                 return read##bwl(XQUAD_PORT_ADDR(port, quad)); \
 286         else \
 287                 return in##bwl##_local(port); \
 288 } \
 289 static inline unsigned type in##bwl(int port) { \
 290         return in##bwl##_quad(port, 0); \
 291 }
 292 #else
 293 #define __BUILDIO(bwl,bw,type) \
 294 static inline void out##bwl(unsigned type value, int port) { \
 295         out##bwl##_local(value, port); \
 296 } \
 297 static inline unsigned type in##bwl(int port) { \
 298         return in##bwl##_local(port); \
 299 }
 300 #endif
 301
 302
 303 #define BUILDIO(bwl,bw,type) \
 304 static inline void out##bwl##_local(unsigned type value, int port) { \
 305         __asm__ __volatile__("out" #bwl " %" #bw "0, %w1" : : "a"(value), "Nd"(port)); \
 306 } \
 307 static inline unsigned type in##bwl##_local(int port) { \
 308         unsigned type value; \
 309         __asm__ __volatile__("in" #bwl " %w1, %" #bw "0" : "=a"(value) : "Nd"(port)); \
 310         return value; \
 311 } \
 312 static inline void out##bwl##_local_p(unsigned type value, int port) { \
 313         out##bwl##_local(value, port); \
 314         slow_down_io(); \
 315 } \
 316 static inline unsigned type in##bwl##_local_p(int port) { \
 317         unsigned type value = in##bwl##_local(port); \
 318         slow_down_io(); \
 319         return value; \
 320 } \
 321 __BUILDIO(bwl,bw,type) \
 322 static inline void out##bwl##_p(unsigned type value, int port) { \
 323         out##bwl(value, port); \
 324         slow_down_io(); \
 325 } \
 326 static inline unsigned type in##bwl##_p(int port) { \
 327         unsigned type value = in##bwl(port); \
 328         slow_down_io(); \
 329         return value; \
 330 } \
 331 static inline void outs##bwl(int port, const void *addr, unsigned long count) { \
 332         __asm__ __volatile__("rep; outs" #bwl : "+S"(addr), "+c"(count) : "d"(port)); \
 333 } \
 334 static inline void ins##bwl(int port, void *addr, unsigned long count) { \
 335         __asm__ __volatile__("rep; ins" #bwl : "+D"(addr), "+c"(count) : "d"(port)); \
 336 }
 337
 338 BUILDIO(b,b,char)
 339 BUILDIO(w,w,short)
 340 BUILDIO(l,,int)
 341
 342 #endif