xref: /linux/arch/mips/sgi-ip27/ip27-console.c (revision 312b62b6610cabea4cb535fd4889c41e9a84afca)
1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Copyright (C) 2001, 2002 Ralf Baechle
7  */
8 
9 #include <asm/page.h>
10 #include <asm/setup.h>
11 #include <asm/sn/addrs.h>
12 #include <asm/sn/agent.h>
13 #include <asm/sn/klconfig.h>
14 #include <asm/sn/ioc3.h>
15 
16 #include <linux/serial.h>
17 #include <linux/serial_core.h>
18 
19 #include "ip27-common.h"
20 
21 #define IOC3_CLK	(22000000 / 3)
22 #define IOC3_FLAGS	(0)
23 
24 static inline struct ioc3_uartregs *console_uart(void)
25 {
26 	struct ioc3 *ioc3;
27 	nasid_t nasid;
28 
29 	nasid = (master_nasid == INVALID_NASID) ? get_nasid() : master_nasid;
30 	ioc3 = (struct ioc3 *)KL_CONFIG_CH_CONS_INFO(nasid)->memory_base;
31 
32 	return &ioc3->sregs.uarta;
33 }
34 
35 void prom_putchar(char c)
36 {
37 	struct ioc3_uartregs *uart = console_uart();
38 
39 	while ((readb(&uart->iu_lsr) & 0x20) == 0)
40 		;
41 	writeb(c, &uart->iu_thr);
42 }
43