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 } 42