xref: /openbmc/linux/arch/mips/lantiq/early_printk.c (revision c7cbb022)
1 /*
2  *  This program is free software; you can redistribute it and/or modify it
3  *  under the terms of the GNU General Public License version 2 as published
4  *  by the Free Software Foundation.
5  *
6  *  Copyright (C) 2010 John Crispin <blogic@openwrt.org>
7  */
8 
9 #include <linux/init.h>
10 #include <linux/cpu.h>
11 
12 #include <lantiq.h>
13 #include <lantiq_soc.h>
14 
15 /* no ioremap possible at this early stage, lets use KSEG1 instead  */
16 #define LTQ_ASC_BASE	KSEG1ADDR(LTQ_ASC1_BASE_ADDR)
17 #define ASC_BUF		1024
18 #define LTQ_ASC_FSTAT	((u32 *)(LTQ_ASC_BASE + 0x0048))
19 #define LTQ_ASC_TBUF	((u32 *)(LTQ_ASC_BASE + 0x0020))
20 #define TXMASK		0x3F00
21 #define TXOFFSET	8
22 
23 void prom_putchar(char c)
24 {
25 	unsigned long flags;
26 
27 	local_irq_save(flags);
28 	do { } while ((ltq_r32(LTQ_ASC_FSTAT) & TXMASK) >> TXOFFSET);
29 	if (c == '\n')
30 		ltq_w32('\r', LTQ_ASC_TBUF);
31 	ltq_w32(c, LTQ_ASC_TBUF);
32 	local_irq_restore(flags);
33 }
34