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

   1/*
   2 * arch/sh/kernel/io.c - Machine independent I/O functions.
   3 *
   4 * Copyright (C) 2000 - 2009  Stuart Menefy
   5 * Copyright (C) 2005  Paul Mundt
   6 *
   7 * This file is subject to the terms and conditions of the GNU General Public
   8 * License.  See the file "COPYING" in the main directory of this archive
   9 * for more details.
  10 */
  11#include <linux/module.h>
  12#include <linux/pci.h>
  13#include <asm/machvec.h>
  14#include <asm/io.h>
  15
  16/*
  17 * Copy data from IO memory space to "real" memory space.
  18 */
  19void memcpy_fromio(void *to, const volatile void __iomem *from, unsigned long count)
  20{
  21        /*
  22         * Would it be worthwhile doing byte and long transfers first
  23         * to try and get aligned?
  24         */
  25#ifdef CONFIG_CPU_SH4
  26        if ((count >= 0x20) &&
  27             (((u32)to & 0x1f) == 0) && (((u32)from & 0x3) == 0)) {
  28                int tmp2, tmp3, tmp4, tmp5, tmp6;
  29
  30                __asm__ __volatile__(
  31                        "1:                     \n\t"
  32                        "mov.l  @%7+, r0        \n\t"
  33                        "mov.l  @%7+, %2        \n\t"
  34                        "movca.l r0, @%0        \n\t"
  35                        "mov.l  @%7+, %3        \n\t"
  36                        "mov.l  @%7+, %4        \n\t"
  37                        "mov.l  @%7+, %5        \n\t"
  38                        "mov.l  @%7+, %6        \n\t"
  39                        "mov.l  @%7+, r7        \n\t"
  40                        "mov.l  @%7+, r0        \n\t"
  41                        "mov.l  %2, @(0x04,%0)  \n\t"
  42                        "mov    #0x20, %2       \n\t"
  43                        "mov.l  %3, @(0x08,%0)  \n\t"
  44                        "sub    %2, %1          \n\t"
  45                        "mov.l  %4, @(0x0c,%0)  \n\t"
  46                        "cmp/hi %1, %2          ! T if 32 > count       \n\t"
  47                        "mov.l  %5, @(0x10,%0)  \n\t"
  48                        "mov.l  %6, @(0x14,%0)  \n\t"
  49                        "mov.l  r7, @(0x18,%0)  \n\t"
  50                        "mov.l  r0, @(0x1c,%0)  \n\t"
  51                        "bf.s   1b              \n\t"
  52                        " add   #0x20, %0       \n\t"
  53                        : "=&r" (to), "=&r" (count),
  54                          "=&r" (tmp2), "=&r" (tmp3), "=&r" (tmp4),
  55                          "=&r" (tmp5), "=&r" (tmp6), "=&r" (from)
  56                        : "7"(from), "0" (to), "1" (count)
  57                        : "r0", "r7", "t", "memory");
  58        }
  59#endif
  60
  61        if ((((u32)to | (u32)from) & 0x3) == 0) {
  62                for (; count > 3; count -= 4) {
  63                        *(u32 *)to = *(volatile u32 *)from;
  64                        to += 4;
  65                        from += 4;
  66                }
  67        }
  68
  69        for (; count > 0; count--) {
  70                *(u8 *)to = *(volatile u8 *)from;
  71                to++;
  72                from++;
  73        }
  74
  75        mb();
  76}
  77EXPORT_SYMBOL(memcpy_fromio);
  78
  79/*
  80 * Copy data from "real" memory space to IO memory space.
  81 */
  82void memcpy_toio(volatile void __iomem *to, const void *from, unsigned long count)
  83{
  84        if ((((u32)to | (u32)from) & 0x3) == 0) {
  85                for ( ; count > 3; count -= 4) {
  86                        *(volatile u32 *)to = *(u32 *)from;
  87                        to += 4;
  88                        from += 4;
  89                }
  90        }
  91
  92        for (; count > 0; count--) {
  93                *(volatile u8 *)to = *(u8 *)from;
  94                to++;
  95                from++;
  96        }
  97
  98        mb();
  99}
 100EXPORT_SYMBOL(memcpy_toio);
 101
 102/*
 103 * "memset" on IO memory space.
 104 * This needs to be optimized.
 105 */
 106void memset_io(volatile void __iomem *dst, int c, unsigned long count)
 107{
 108        while (count) {
 109                count--;
 110                writeb(c, dst);
 111                dst++;
 112        }
 113}
 114EXPORT_SYMBOL(memset_io);
 115