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
  15 static 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
  24 static 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
  35 static 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 }