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
21void 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

source code of linux/arch/mips/lantiq/early_printk.c