/* SPDX-License-Identifier: GPL-2.0 */
/*
* include/linux/vt_buffer.h -- Access to VT screen buffer
*
* (c) 1998 Martin Mares <mj@ucw.cz>
*
* 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_
#include <linux/string.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))
#endif
#ifndef VT_BUF_HAVE_MEMSETW
static inline void scr_memsetw(u16 *s, u16 c, unsigned int count)
{
#ifdef VT_BUF_HAVE_RW
count /= 2;
while (count--)
scr_writew(c, s++);
#else
memset16(s, c, count / 2);
#endif
}
#endif
#ifndef VT_BUF_HAVE_MEMCPYW
static inline void scr_memcpyw(u16 *d, const u16 *s, unsigned int count)
{
#ifdef VT_BUF_HAVE_RW
count /= 2;
while (count--)
scr_writew(scr_readw(s++), d++);
#else
memcpy(d, s, count);
#endif
}
#endif
#ifndef VT_BUF_HAVE_MEMMOVEW
static inline void scr_memmovew(u16 *d, const u16 *s, unsigned int count)
{
#ifdef VT_BUF_HAVE_RW
if (d < s)
scr_memcpyw(d, s, count);
else {
count /= 2;
d += count;
s += count;
while (count--)
scr_writew(scr_readw(--s), --d);
}
#else
memmove(d, s, count);
#endif
}
#endif
#endif
