xref: /openbmc/linux/arch/mips/lantiq/early_printk.c (revision 12eb4683)
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/cpu.h>
10 #include <lantiq_soc.h>
11 
12 #define ASC_BUF		1024
13 #define LTQ_ASC_FSTAT	((u32 *)(LTQ_EARLY_ASC + 0x0048))
14 #ifdef __BIG_ENDIAN
15 #define LTQ_ASC_TBUF	((u32 *)(LTQ_EARLY_ASC + 0x0020 + 3))
16 #else
17 #define LTQ_ASC_TBUF	((u32 *)(LTQ_EARLY_ASC + 0x0020))
18 #endif
19 #define TXMASK		0x3F00
20 #define TXOFFSET	8
21 
22 void prom_putchar(char c)
23 {
24 	unsigned long flags;
25 
26 	local_irq_save(flags);
27 	do { } while ((ltq_r32(LTQ_ASC_FSTAT) & TXMASK) >> TXOFFSET);
28 	if (c == '\n')
29 		ltq_w8('\r', LTQ_ASC_TBUF);
30 	ltq_w8(c, LTQ_ASC_TBUF);
31 	local_irq_restore(flags);
32 }
33