/*
* include/linux/vt_buffer.h -- Access to VT screen buffer
*
* (c) 1998 Martin Mares <[email protected]>
*
* This is a set of macros and functions which are used in the
* console driver and related code to access the screen buffer.
* In most cases the console works with simple in-memory buffer,
* but when handling hardware text mode consoles, we store
* the foreground console directly in video memory.
*/

#ifndef _LINUX_VT_BUFFER_H_
#define _LINUX_VT_BUFFER_H_


#if defined(CONFIG_VGA_CONSOLE) || defined(CONFIG_MDA_CONSOLE)
#include <asm/vga.h>
#endif

#ifndef VT_BUF_HAVE_RW
#define scr_writew(val, addr) (*(addr) = (val))
#define scr_readw(addr) (*(addr))
#define scr_memcpyw(d, s, c) memcpy(d, s, c)
#define scr_memmovew(d, s, c) memmove(d, s, c)
#define VT_BUF_HAVE_MEMCPYW
#define VT_BUF_HAVE_MEMMOVEW
#endif

#ifndef VT_BUF_HAVE_MEMSETW
static inline void scr_memsetw(u16 *s, u16 c, unsigned int count)
{
count /= 2;
while (count--)
scr_writew(c, s++);
}
#endif

#ifndef VT_BUF_HAVE_MEMCPYW
static inline void scr_memcpyw(u16 *d, const u16 *s, unsigned int count)
{
count /= 2;
while (count--)
scr_writew(scr_readw(s++), d++);
}
#endif

#ifndef VT_BUF_HAVE_MEMMOVEW
static inline void scr_memmovew(u16 *d, const u16 *s, unsigned int count)
{
if (d < s)
scr_memcpyw(d, s, count);
else {
count /= 2;
d += count;
s += count;
while (count--)
scr_writew(scr_readw(--s), --d);
}
}
#endif

#endif