Linux Kernel  3.7.1
 All Data Structures Namespaces Files Functions Variables Typedefs Enumerations Enumerator Macros Groups Pages
promlib.c
Go to the documentation of this file.
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 ([email protected])
7  * Compatibility with board caches, Ulf Carlsson
8  */
9 #include <linux/kernel.h>
10 #include <asm/sgialib.h>
11 #include <asm/bcache.h>
12 
13 /*
14  * IP22 boardcache is not compatible with board caches. Thus we disable it
15  * during romvec action. Since r4xx0.c is always compiled and linked with your
16  * kernel, this shouldn't cause any harm regardless what MIPS processor you
17  * have.
18  *
19  * The ARC write and read functions seem to interfere with the serial lines
20  * in some way. You should be careful with them.
21  */
22 
23 void prom_putchar(char c)
24 {
25  ULONG cnt;
26  CHAR it = c;
27 
28  bc_disable();
29  ArcWrite(1, &it, 1, &cnt);
30  bc_enable();
31 }
32 
33 char prom_getchar(void)
34 {
35  ULONG cnt;
36  CHAR c;
37 
38  bc_disable();
39  ArcRead(0, &c, 1, &cnt);
40  bc_enable();
41 
42  return c;
43 }