LXR linux/arch/arm/include/asm/dcc.h

   1/* Copyright (c) 2010, 2014 The Linux Foundation. All rights reserved.
   2 *
   3 * This program is free software; you can redistribute it and/or modify
   4 * it under the terms of the GNU General Public License version 2 and
   5 * only version 2 as published by the Free Software Foundation.
   6 *
   7 * This program is distributed in the hope that it will be useful,
   8 * but WITHOUT ANY WARRANTY; without even the implied warranty of
   9 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  10 * GNU General Public License for more details.
  11 */
  12
  13#include <asm/barrier.h>
  14
  15static inline u32 __dcc_getstatus(void)
  16{
  17        u32 __ret;
  18        asm volatile("mrc p14, 0, %0, c0, c1, 0 @ read comms ctrl reg"
  19                : "=r" (__ret) : : "cc");
  20
  21        return __ret;
  22}
  23
  24static inline char __dcc_getchar(void)
  25{
  26        char __c;
  27
  28        asm volatile("mrc p14, 0, %0, c0, c5, 0 @ read comms data reg"
  29                : "=r" (__c));
  30        isb();
  31
  32        return __c;
  33}
  34
  35static inline void __dcc_putchar(char c)
  36{
  37        asm volatile("mcr p14, 0, %0, c0, c5, 0 @ write a char"
  38                : /* no output register */
  39                : "r" (c));
  40        isb();
  41}
  42