arch/mips/fw/arc/promlib.c

   1 /*
   2  * This file is subject to the terms and conditions of the GNU General Public
   3  * License.  See the file "COPYING" in the main directory of this archive
   4  * for more details.
   5  *
   6  * Copyright (C) 1996 David S. Miller (dm@sgi.com)
   7  * Compatibility with board caches, Ulf Carlsson
   8  */
   9 #include <linux/kernel.h>
  10 #include <asm/sgialib.h>
  11 #include <asm/bcache.h>
  12 #include <asm/setup.h>
  13
  14 /*
  15  * IP22 boardcache is not compatible with board caches.  Thus we disable it
  16  * during romvec action.  Since r4xx0.c is always compiled and linked with your
  17  * kernel, this shouldn't cause any harm regardless what MIPS processor you
  18  * have.
  19  *
  20  * The ARC write and read functions seem to interfere with the serial lines
  21  * in some way. You should be careful with them.
  22  */
  23
  24 void prom_putchar(char c)
  25 {
  26         ULONG cnt;
  27         CHAR it = c;
  28
  29         bc_disable();
  30         ArcWrite(1, &it, 1, &cnt);
  31         bc_enable();
  32 }
  33
  34 char prom_getchar(void)
  35 {
  36         ULONG cnt;
  37         CHAR c;
  38
  39         bc_disable();
  40         ArcRead(0, &c, 1, &cnt);
  41         bc_enable();
  42
  43         return c;
  44 }