arch/arm/kernel/io.c

   1 #include <linux/module.h>
   2 #include <linux/types.h>
   3 #include <linux/io.h>
   4
   5 /*
   6  * Copy data from IO memory space to "real" memory space.
   7  * This needs to be optimized.
   8  */
   9 void _memcpy_fromio(void *to, const volatile void __iomem *from, size_t count)
  10 {
  11         unsigned char *t = to;
  12         while (count) {
  13                 count--;
  14                 *t = readb(from);
  15                 t++;
  16                 from++;
  17         }
  18 }
  19
  20 /*
  21  * Copy data from "real" memory space to IO memory space.
  22  * This needs to be optimized.
  23  */
  24 void _memcpy_toio(volatile void __iomem *to, const void *from, size_t count)
  25 {
  26         const unsigned char *f = from;
  27         while (count) {
  28                 count--;
  29                 writeb(*f, to);
  30                 f++;
  31                 to++;
  32         }
  33 }
  34
  35 /*
  36  * "memset" on IO memory space.
  37  * This needs to be optimized.
  38  */
  39 void _memset_io(volatile void __iomem *dst, int c, size_t count)
  40 {
  41         while (count) {
  42                 count--;
  43                 writeb(c, dst);
  44                 dst++;
  45         }
  46 }
  47
  48 EXPORT_SYMBOL(_memcpy_fromio);
  49 EXPORT_SYMBOL(_memcpy_toio);
  50 EXPORT_SYMBOL(_memset_io);