LXR linux/arch/m68k/kernel/early

   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) 2014 Finn Thain
   7 */
   8
   9#include <linux/kernel.h>
  10#include <linux/console.h>
  11#include <linux/init.h>
  12#include <linux/string.h>
  13#include <asm/setup.h>
  14
  15extern void mvme16x_cons_write(struct console *co,
  16                               const char *str, unsigned count);
  17
  18asmlinkage void __init debug_cons_nputs(const char *s, unsigned n);
  19
  20static void __ref debug_cons_write(struct console *c,
  21                                   const char *s, unsigned n)
  22{
  23#if !(defined(CONFIG_SUN3) || defined(CONFIG_M68000) || \
  24      defined(CONFIG_COLDFIRE))
  25        if (MACH_IS_MVME16x)
  26                mvme16x_cons_write(c, s, n);
  27        else
  28                debug_cons_nputs(s, n);
  29#endif
  30}
  31
  32static struct console early_console_instance = {
  33        .name  = "debug",
  34        .write = debug_cons_write,
  35        .flags = CON_PRINTBUFFER | CON_BOOT,
  36        .index = -1
  37};
  38
  39static int __init setup_early_printk(char *buf)
  40{
  41        if (early_console || buf)
  42                return 0;
  43
  44        early_console = &early_console_instance;
  45        register_console(early_console);
  46
  47        return 0;
  48}
  49early_param("earlyprintk", setup_early_printk);
  50
  51/*
  52 * debug_cons_nputs() defined in arch/m68k/kernel/head.S cannot be called
  53 * after init sections are discarded (for platforms that use it).
  54 */
  55#if !(defined(CONFIG_SUN3) || defined(CONFIG_M68000) || \
  56      defined(CONFIG_COLDFIRE))
  57
  58static int __init unregister_early_console(void)
  59{
  60        if (!early_console || MACH_IS_MVME16x)
  61                return 0;
  62
  63        return unregister_console(early_console);
  64}
  65late_initcall(unregister_early_console);
  66
  67#endif
  68