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 27static 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 36static 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 45static 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