mirror of
https://github.com/torvalds/linux.git
synced 2024-12-21 18:42:44 +00:00
93fd03a8c6
This patch allows an earlyprintk console if CONFIG_DEBUG_LL is enabled, using the printch asm function. The patch is based on the original work by Sascha Hauer. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Sascha Hauer <s.hauer@pengutronix.de> Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Acked-by: Pavel Machek <pavel@ucw.cz>
58 lines
1.1 KiB
C
58 lines
1.1 KiB
C
/*
|
|
* linux/arch/arm/kernel/early_printk.c
|
|
*
|
|
* Copyright (C) 2009 Sascha Hauer <s.hauer@pengutronix.de>
|
|
*
|
|
* 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.
|
|
*/
|
|
|
|
#include <linux/kernel.h>
|
|
#include <linux/console.h>
|
|
#include <linux/init.h>
|
|
|
|
extern void printch(int);
|
|
|
|
static void early_write(const char *s, unsigned n)
|
|
{
|
|
while (n-- > 0) {
|
|
if (*s == '\n')
|
|
printch('\r');
|
|
printch(*s);
|
|
s++;
|
|
}
|
|
}
|
|
|
|
static void early_console_write(struct console *con, const char *s, unsigned n)
|
|
{
|
|
early_write(s, n);
|
|
}
|
|
|
|
static struct console early_console = {
|
|
.name = "earlycon",
|
|
.write = early_console_write,
|
|
.flags = CON_PRINTBUFFER | CON_BOOT,
|
|
.index = -1,
|
|
};
|
|
|
|
asmlinkage void early_printk(const char *fmt, ...)
|
|
{
|
|
char buf[512];
|
|
int n;
|
|
va_list ap;
|
|
|
|
va_start(ap, fmt);
|
|
n = vscnprintf(buf, sizeof(buf), fmt, ap);
|
|
early_write(buf, n);
|
|
va_end(ap);
|
|
}
|
|
|
|
static int __init setup_early_printk(char *buf)
|
|
{
|
|
register_console(&early_console);
|
|
return 0;
|
|
}
|
|
|
|
early_param("earlyprintk", setup_early_printk);
|