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

   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * arch/sh/kernel/io.c - Machine independent I/O functions.
   4 *
   5 * Copyright (C) 2000 - 2009  Stuart Menefy
   6 * Copyright (C) 2005  Paul Mundt
   7 */
   8#include <linux/module.h>
   9#include <linux/pci.h>
  10#include <asm/machvec.h>
  11#include <asm/io.h>
  12
  13/*
  14 * Copy data from IO memory space to "real" memory space.
  15 */
  16void memcpy_fromio(void *to, const volatile void __iomem *from, unsigned long count)
  17{
  18        /*
  19         * Would it be worthwhile doing byte and long transfers first
  20         * to try and get aligned?
  21         */
  22#ifdef CONFIG_CPU_SH4
  23        if ((count >= 0x20) &&
  24             (((u32)to & 0x1f) == 0) && (((u32)from & 0x3) == 0)) {
  25                int tmp2, tmp3, tmp4, tmp5, tmp6;
  26
  27                __asm__ __volatile__(
  28                        "1:                     \n\t"
  29                        "mov.l  @%7+, r0        \n\t"
  30                        "mov.l  @%7+, %2        \n\t"
  31                        "movca.l r0, @%0        \n\t"
  32                        "mov.l  @%7+, %3        \n\t"
  33                        "mov.l  @%7+, %4        \n\t"
  34                        "mov.l  @%7+, %5        \n\t"
  35                        "mov.l  @%7+, %6        \n\t"
  36                        "mov.l  @%7+, r7        \n\t"
  37                        "mov.l  @%7+, r0        \n\t"
  38                        "mov.l  %2, @(0x04,%0)  \n\t"
  39                        "mov    #0x20, %2       \n\t"
  40                        "mov.l  %3, @(0x08,%0)  \n\t"
  41                        "sub    %2, %1          \n\t"
  42                        "mov.l  %4, @(0x0c,%0)  \n\t"
  43                        "cmp/hi %1, %2          ! T if 32 > count       \n\t"
  44                        "mov.l  %5, @(0x10,%0)  \n\t"
  45                        "mov.l  %6, @(0x14,%0)  \n\t"
  46                        "mov.l  r7, @(0x18,%0)  \n\t"
  47                        "mov.l  r0, @(0x1c,%0)  \n\t"
  48                        "bf.s   1b              \n\t"
  49                        " add   #0x20, %0       \n\t"
  50                        : "=&r" (to), "=&r" (count),
  51                          "=&r" (tmp2), "=&r" (tmp3), "=&r" (tmp4),
  52                          "=&r" (tmp5), "=&r" (tmp6), "=&r" (from)
  53                        : "7"(from), "0" (to), "1" (count)
  54                        : "r0", "r7", "t", "memory");
  55        }
  56#endif
  57
  58        if ((((u32)to | (u32)from) & 0x3) == 0) {
  59                for (; count > 3; count -= 4) {
  60                        *(u32 *)to = *(volatile u32 *)from;
  61                        to += 4;
  62                        from += 4;
  63                }
  64        }
  65
  66        for (; count > 0; count--) {
  67                *(u8 *)to = *(volatile u8 *)from;
  68                to++;
  69                from++;
  70        }
  71
  72        mb();
  73}
  74EXPORT_SYMBOL(memcpy_fromio);
  75
  76/*
  77 * Copy data from "real" memory space to IO memory space.
  78 */
  79void memcpy_toio(volatile void __iomem *to, const void *from, unsigned long count)
  80{
  81        if ((((u32)to | (u32)from) & 0x3) == 0) {
  82                for ( ; count > 3; count -= 4) {
  83                        *(volatile u32 *)to = *(u32 *)from;
  84                        to += 4;
  85                        from += 4;
  86                }
  87        }
  88
  89        for (; count > 0; count--) {
  90                *(volatile u8 *)to = *(u8 *)from;
  91                to++;
  92                from++;
  93        }
  94
  95        mb();
  96}
  97EXPORT_SYMBOL(memcpy_toio);
  98
  99/*
 100 * "memset" on IO memory space.
 101 * This needs to be optimized.
 102 */
 103void memset_io(volatile void __iomem *dst, int c, unsigned long count)
 104{
 105        while (count) {
 106                count--;
 107                writeb(c, dst);
 108                dst++;
 109        }
 110}
 111EXPORT_SYMBOL(memset_io);
 112