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 extern void prom_putchar(char);
  14
  15 static void __init
  16 early_console_write(struct console *con, const char *s, unsigned n)
  17 {
  18         while (n-- && *s) {
  19                 if (*s == '\n')
  20                         prom_putchar('\r');
  21                 prom_putchar(*s);
  22                 s++;
  23         }
  24 }
  25
  26 static struct console early_console __initdata = {
  27         .name   = "early",
  28         .write  = early_console_write,
  29         .flags  = CON_PRINTBUFFER | CON_BOOT,
  30         .index  = -1
  31 };
  32
  33 static int early_console_initialized __initdata;
  34
  35 void __init setup_early_printk(void)
  36 {
  37         if (early_console_initialized)
  38                 return;
  39         early_console_initialized = 1;
  40
  41         register_console(&early_console);
  42 }