root/arch/sh/kernel/io.c

DEFINITIONS

1. memcpy_fromio
2. memcpy_toio
3. memset_io

   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  */
  16 void 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 }
  74 EXPORT_SYMBOL(memcpy_fromio);
  75 
  76 /*
  77  * Copy data from "real" memory space to IO memory space.
  78  */
  79 void 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 }
  97 EXPORT_SYMBOL(memcpy_toio);
  98 
  99 /*
 100  * "memset" on IO memory space.
 101  * This needs to be optimized.
 102  */
 103 void 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 }
 111 EXPORT_SYMBOL(memset_io);