1/*
 2 * arch/h8300/kernel/sim-console.c
 3 *
 4 *  Copyright (C) 2015 Yoshinori Sato <ysato@users.sourceforge.jp>
 5 *
 6 * This file is subject to the terms and conditions of the GNU General Public
 7 * License.  See the file "COPYING" in the main directory of this archive
 8 * for more details.
 9 */
10#include <linux/console.h>
11#include <linux/init.h>
12#include <linux/serial_core.h>
13
14static void sim_write(struct console *con, const char *s, unsigned n)
15{
16	register const char *_ptr __asm__("er1") = s;
17	register const unsigned _len __asm__("er2") = n;
18
19	__asm__("sub.l er0,er0\n\t"		/* er0 = 1 (stdout) */
20		"inc.l #1,er0\n\t"
21		".byte 0x5e,0x00,0x00,0xc7\n\t" /* jsr @0xc7 (sys_write) */
22		: : "g"(_ptr), "g"(_len):"er0");
23}
24
25static int __init sim_setup(struct earlycon_device *device, const char *opt)
26{
27	device->con->write = sim_write;
28	return 0;
29}
30
31EARLYCON_DECLARE(h8sim, sim_setup);