arch/mips/kernel/early_printk.c

   1 /*
   2  * This file is subject to the terms and conditions of the GNU General Public
   3  * License.  See the file "COPYING" in the main directory of this archive
   4  * for more details.
   5  *
   6  * Copyright (C) 2002, 2003, 06, 07 Ralf Baechle (ralf@linux-mips.org)
   7  * Copyright (C) 2007 MIPS Technologies, Inc.
   8  *   written by Ralf Baechle (ralf@linux-mips.org)
   9  */
  10 #include <linux/console.h>
  11 #include <linux/init.h>
  12
  13 #include <asm/setup.h>
  14
  15 extern void prom_putchar(char);
  16
  17 static void __init
  18 early_console_write(struct console *con, const char *s, unsigned n)
  19 {
  20         while (n-- && *s) {
  21                 if (*s == '\n')
  22                         prom_putchar('\r');
  23                 prom_putchar(*s);
  24                 s++;
  25         }
  26 }
  27
  28 static struct console early_console __initdata = {
  29         .name   = "early",
  30         .write  = early_console_write,
  31         .flags  = CON_PRINTBUFFER | CON_BOOT,
  32         .index  = -1
  33 };
  34
  35 static int early_console_initialized __initdata;
  36
  37 void __init setup_early_printk(void)
  38 {
  39         if (early_console_initialized)
  40                 return;
  41         early_console_initialized = 1;
  42
  43         register_console(&early_console);
  44 }