File: early_printk.c

package info (click to toggle)
linux 4.19.37-3
  • links: PTS, VCS
  • area: main
  • in suites: buster
  • size: 962,264 kB
  • sloc: ansic: 16,757,120; asm: 271,404; makefile: 38,285; sh: 33,529; perl: 27,681; python: 21,031; cpp: 5,063; yacc: 4,648; lex: 2,585; awk: 1,385; ruby: 25; sed: 5
file content (33 lines) | stat: -rw-r--r-- 834 bytes parent folder | download | duplicates (7)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
/*
 *  This program is free software; you can redistribute it and/or modify it
 *  under the terms of the GNU General Public License version 2 as published
 *  by the Free Software Foundation.
 *
 *  Copyright (C) 2010 John Crispin <john@phrozen.org>
 */

#include <linux/cpu.h>
#include <lantiq_soc.h>
#include <asm/setup.h>

#define ASC_BUF		1024
#define LTQ_ASC_FSTAT	((u32 *)(LTQ_EARLY_ASC + 0x0048))
#ifdef __BIG_ENDIAN
#define LTQ_ASC_TBUF	((u32 *)(LTQ_EARLY_ASC + 0x0020 + 3))
#else
#define LTQ_ASC_TBUF	((u32 *)(LTQ_EARLY_ASC + 0x0020))
#endif
#define TXMASK		0x3F00
#define TXOFFSET	8

void prom_putchar(char c)
{
	unsigned long flags;

	local_irq_save(flags);
	do { } while ((ltq_r32(LTQ_ASC_FSTAT) & TXMASK) >> TXOFFSET);
	if (c == '\n')
		ltq_w8('\r', LTQ_ASC_TBUF);
	ltq_w8(c, LTQ_ASC_TBUF);
	local_irq_restore(flags);
}