arch/mips/mti-malta/malta-display.c

   1 /*
   2  * Carsten Langgaard, carstenl@mips.com
   3  * Copyright (C) 1999,2000 MIPS Technologies, Inc.  All rights reserved.
   4  *
   5  *  This program is free software; you can distribute it and/or modify it
   6  *  under the terms of the GNU General Public License (Version 2) as
   7  *  published by the Free Software Foundation.
   8  *
   9  *  This program is distributed in the hope it will be useful, but WITHOUT
  10  *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  *  for more details.
  13  *
  14  *  You should have received a copy of the GNU General Public License along
  15  *  with this program; if not, write to the Free Software Foundation, Inc.,
  16  *  59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
  17  *
  18  * Display routines for display messages in MIPS boards ascii display.
  19  */
  20
  21 #include <linux/compiler.h>
  22 #include <linux/timer.h>
  23 #include <asm/io.h>
  24 #include <asm/mips-boards/generic.h>
  25 #include <asm/mips-boards/prom.h>
  26
  27 extern const char display_string[];
  28 static unsigned int display_count;
  29 static unsigned int max_display_count;
  30
  31 void mips_display_message(const char *str)
  32 {
  33         static unsigned int __iomem *display = NULL;
  34         int i;
  35
  36         if (unlikely(display == NULL))
  37                 display = ioremap(ASCII_DISPLAY_POS_BASE, 16*sizeof(int));
  38
  39         for (i = 0; i <= 14; i=i+2) {
  40                  if (*str)
  41                          __raw_writel(*str++, display + i);
  42                  else
  43                          __raw_writel(' ', display + i);
  44         }
  45 }
  46
  47 static void scroll_display_message(unsigned long data);
  48 static DEFINE_TIMER(mips_scroll_timer, scroll_display_message, HZ, 0);
  49
  50 static void scroll_display_message(unsigned long data)
  51 {
  52         mips_display_message(&display_string[display_count++]);
  53         if (display_count == max_display_count)
  54                 display_count = 0;
  55
  56         mod_timer(&mips_scroll_timer, jiffies + HZ);
  57 }
  58
  59 void mips_scroll_message(void)
  60 {
  61         del_timer_sync(&mips_scroll_timer);
  62         max_display_count = strlen(display_string) + 1 - 8;
  63         mod_timer(&mips_scroll_timer, jiffies + 1);
  64 }