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/*
* 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);
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