xref: /openbmc/linux/arch/mips/lantiq/early_printk.c (revision 2cf1c348)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *
4  *  Copyright (C) 2010 John Crispin <john@phrozen.org>
5  */
6 
7 #include <linux/cpu.h>
8 #include <lantiq_soc.h>
9 #include <asm/setup.h>
10 
11 #define ASC_BUF		1024
12 #define LTQ_ASC_FSTAT	((u32 *)(LTQ_EARLY_ASC + 0x0048))
13 #ifdef __BIG_ENDIAN
14 #define LTQ_ASC_TBUF	((u32 *)(LTQ_EARLY_ASC + 0x0020 + 3))
15 #else
16 #define LTQ_ASC_TBUF	((u32 *)(LTQ_EARLY_ASC + 0x0020))
17 #endif
18 #define TXMASK		0x3F00
19 #define TXOFFSET	8
20 
21 void prom_putchar(char c)
22 {
23 	unsigned long flags;
24 
25 	local_irq_save(flags);
26 	do { } while ((ltq_r32(LTQ_ASC_FSTAT) & TXMASK) >> TXOFFSET);
27 	if (c == '\n')
28 		ltq_w8('\r', LTQ_ASC_TBUF);
29 	ltq_w8(c, LTQ_ASC_TBUF);
30 	local_irq_restore(flags);
31 }
32