1 /*
2 * include/linux/vt_buffer.h -- Access to VT screen buffer
3 *
4 * (c) 1998 Martin Mares <mj@ucw.cz>
5 *
6 * This is a set of macros and functions which are used in the
7 * console driver and related code to access the screen buffer.
8 * In most cases the console works with simple in-memory buffer,
9 * but when handling hardware text mode consoles, we store
10 * the foreground console directly in video memory.
11 */
12
13 #ifndef _LINUX_VT_BUFFER_H_
14 #define _LINUX_VT_BUFFER_H_
15
16
17 #if defined(CONFIG_VGA_CONSOLE) || defined(CONFIG_MDA_CONSOLE)
18 #include <asm/vga.h>
19 #endif
20
21 #ifndef VT_BUF_HAVE_RW
22 #define scr_writew(val, addr) (*(addr) = (val))
23 #define scr_readw(addr) (*(addr))
24 #endif
25
26 #ifndef VT_BUF_HAVE_MEMSETW
scr_memsetw(u16 * s,u16 c,unsigned int count)27 static inline void scr_memsetw(u16 *s, u16 c, unsigned int count)
28 {
29 count /= 2;
30 while (count--)
31 scr_writew(c, s++);
32 }
33 #endif
34
35 #ifndef VT_BUF_HAVE_MEMCPYW
scr_memcpyw(u16 * d,const u16 * s,unsigned int count)36 static inline void scr_memcpyw(u16 *d, const u16 *s, unsigned int count)
37 {
38 count /= 2;
39 while (count--)
40 scr_writew(scr_readw(s++), d++);
41 }
42 #endif
43
44 #ifndef VT_BUF_HAVE_MEMMOVEW
scr_memmovew(u16 * d,const u16 * s,unsigned int count)45 static inline void scr_memmovew(u16 *d, const u16 *s, unsigned int count)
46 {
47 if (d < s)
48 scr_memcpyw(d, s, count);
49 else {
50 count /= 2;
51 d += count;
52 s += count;
53 while (count--)
54 scr_writew(scr_readw(--s), --d);
55 }
56 }
57 #endif
58
59 #endif
60