LXR linux/arch/powerpc/kernel/io.c

   1/*
   2 * I/O string operations
   3 *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
   4 *    Copyright (C) 2006 IBM Corporation
   5 *
   6 * Largely rewritten by Cort Dougan (cort@cs.nmt.edu)
   7 * and Paul Mackerras.
   8 *
   9 * Adapted for iSeries by Mike Corrigan (mikejc@us.ibm.com)
  10 * PPC64 updates by Dave Engebretsen (engebret@us.ibm.com)
  11 *
  12 * Rewritten in C by Stephen Rothwell.
  13 *
  14 * This program is free software; you can redistribute it and/or
  15 * modify it under the terms of the GNU General Public License
  16 * as published by the Free Software Foundation; either version
  17 * 2 of the License, or (at your option) any later version.
  18 */
  19#include <linux/kernel.h>
  20#include <linux/types.h>
  21#include <linux/compiler.h>
  22#include <linux/module.h>
  23
  24#include <asm/io.h>
  25#include <asm/firmware.h>
  26#include <asm/bug.h>
  27
  28void _insb(const volatile u8 __iomem *port, void *buf, long count)
  29{
  30        u8 *tbuf = buf;
  31        u8 tmp;
  32
  33        if (unlikely(count <= 0))
  34                return;
  35        asm volatile("sync");
  36        do {
  37                tmp = *port;
  38                eieio();
  39                *tbuf++ = tmp;
  40        } while (--count != 0);
  41        asm volatile("twi 0,%0,0; isync" : : "r" (tmp));
  42}
  43EXPORT_SYMBOL(_insb);
  44
  45void _outsb(volatile u8 __iomem *port, const void *buf, long count)
  46{
  47        const u8 *tbuf = buf;
  48
  49        if (unlikely(count <= 0))
  50                return;
  51        asm volatile("sync");
  52        do {
  53                *port = *tbuf++;
  54        } while (--count != 0);
  55        asm volatile("sync");
  56}
  57EXPORT_SYMBOL(_outsb);
  58
  59void _insw_ns(const volatile u16 __iomem *port, void *buf, long count)
  60{
  61        u16 *tbuf = buf;
  62        u16 tmp;
  63
  64        if (unlikely(count <= 0))
  65                return;
  66        asm volatile("sync");
  67        do {
  68                tmp = *port;
  69                eieio();
  70                *tbuf++ = tmp;
  71        } while (--count != 0);
  72        asm volatile("twi 0,%0,0; isync" : : "r" (tmp));
  73}
  74EXPORT_SYMBOL(_insw_ns);
  75
  76void _outsw_ns(volatile u16 __iomem *port, const void *buf, long count)
  77{
  78        const u16 *tbuf = buf;
  79
  80        if (unlikely(count <= 0))
  81                return;
  82        asm volatile("sync");
  83        do {
  84                *port = *tbuf++;
  85        } while (--count != 0);
  86        asm volatile("sync");
  87}
  88EXPORT_SYMBOL(_outsw_ns);
  89
  90void _insl_ns(const volatile u32 __iomem *port, void *buf, long count)
  91{
  92        u32 *tbuf = buf;
  93        u32 tmp;
  94
  95        if (unlikely(count <= 0))
  96                return;
  97        asm volatile("sync");
  98        do {
  99                tmp = *port;
 100                eieio();
 101                *tbuf++ = tmp;
 102        } while (--count != 0);
 103        asm volatile("twi 0,%0,0; isync" : : "r" (tmp));
 104}
 105EXPORT_SYMBOL(_insl_ns);
 106
 107void _outsl_ns(volatile u32 __iomem *port, const void *buf, long count)
 108{
 109        const u32 *tbuf = buf;
 110
 111        if (unlikely(count <= 0))
 112                return;
 113        asm volatile("sync");
 114        do {
 115                *port = *tbuf++;
 116        } while (--count != 0);
 117        asm volatile("sync");
 118}
 119EXPORT_SYMBOL(_outsl_ns);
 120
 121#define IO_CHECK_ALIGN(v,a) ((((unsigned long)(v)) & ((a) - 1)) == 0)
 122
 123void _memset_io(volatile void __iomem *addr, int c, unsigned long n)
 124{
 125        void *p = (void __force *)addr;
 126        u32 lc = c;
 127        lc |= lc << 8;
 128        lc |= lc << 16;
 129
 130        __asm__ __volatile__ ("sync" : : : "memory");
 131        while(n && !IO_CHECK_ALIGN(p, 4)) {
 132                *((volatile u8 *)p) = c;
 133                p++;
 134                n--;
 135        }
 136        while(n >= 4) {
 137                *((volatile u32 *)p) = lc;
 138                p += 4;
 139                n -= 4;
 140        }
 141        while(n) {
 142                *((volatile u8 *)p) = c;
 143                p++;
 144                n--;
 145        }
 146        __asm__ __volatile__ ("sync" : : : "memory");
 147}
 148EXPORT_SYMBOL(_memset_io);
 149
 150void _memcpy_fromio(void *dest, const volatile void __iomem *src,
 151                    unsigned long n)
 152{
 153        void *vsrc = (void __force *) src;
 154
 155        __asm__ __volatile__ ("sync" : : : "memory");
 156        while(n && (!IO_CHECK_ALIGN(vsrc, 4) || !IO_CHECK_ALIGN(dest, 4))) {
 157                *((u8 *)dest) = *((volatile u8 *)vsrc);
 158                eieio();
 159                vsrc++;
 160                dest++;
 161                n--;
 162        }
 163        while(n > 4) {
 164                *((u32 *)dest) = *((volatile u32 *)vsrc);
 165                eieio();
 166                vsrc += 4;
 167                dest += 4;
 168                n -= 4;
 169        }
 170        while(n) {
 171                *((u8 *)dest) = *((volatile u8 *)vsrc);
 172                eieio();
 173                vsrc++;
 174                dest++;
 175                n--;
 176        }
 177        __asm__ __volatile__ ("sync" : : : "memory");
 178}
 179EXPORT_SYMBOL(_memcpy_fromio);
 180
 181void _memcpy_toio(volatile void __iomem *dest, const void *src, unsigned long n)
 182{
 183        void *vdest = (void __force *) dest;
 184
 185        __asm__ __volatile__ ("sync" : : : "memory");
 186        while(n && (!IO_CHECK_ALIGN(vdest, 4) || !IO_CHECK_ALIGN(src, 4))) {
 187                *((volatile u8 *)vdest) = *((u8 *)src);
 188                src++;
 189                vdest++;
 190                n--;
 191        }
 192        while(n > 4) {
 193                *((volatile u32 *)vdest) = *((volatile u32 *)src);
 194                src += 4;
 195                vdest += 4;
 196                n-=4;
 197        }
 198        while(n) {
 199                *((volatile u8 *)vdest) = *((u8 *)src);
 200                src++;
 201                vdest++;
 202                n--;
 203        }
 204        __asm__ __volatile__ ("sync" : : : "memory");
 205}
 206EXPORT_SYMBOL(_memcpy_toio);
 207