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
6 * Copyright (C) 2012 MIPS Technologies, Inc. All rights reserved.
8 #include <linux/timer.h>
10 #include <asm/mips-boards/generic.h>
11 #include <asm/mips-boards/prom.h>
13 static unsigned int display_count;
14 static unsigned int max_display_count;
16 #define LCD_DISPLAY_POS_BASE 0x1f000400
17 #define DISPLAY_LCDINSTRUCTION (0*2)
18 #define DISPLAY_LCDDATA (1*2)
19 #define DISPLAY_CPLDSTATUS (2*2)
20 #define DISPLAY_CPLDDATA (3*2)
21 #define LCD_SETDDRAM 0x80
22 #define LCD_IR_BF 0x80
24 const char display_string[] = " LINUX ON SEAD3 ";
26 static void scroll_display_message(unsigned long data);
27 static DEFINE_TIMER(mips_scroll_timer, scroll_display_message, HZ, 0);
29 static void lcd_wait(unsigned int __iomem *display)
31 /* Wait for CPLD state machine to become idle. */
32 do { } while (__raw_readl(display + DISPLAY_CPLDSTATUS) & 1);
35 __raw_readl(display + DISPLAY_LCDINSTRUCTION);
37 /* Wait for CPLD state machine to become idle. */
38 do { } while (__raw_readl(display + DISPLAY_CPLDSTATUS) & 1);
39 } while (__raw_readl(display + DISPLAY_CPLDDATA) & LCD_IR_BF);
42 void mips_display_message(const char *str)
44 static unsigned int __iomem *display;
48 if (unlikely(display == NULL))
49 display = ioremap_nocache(LCD_DISPLAY_POS_BASE,
52 for (i = 0; i < 16; i++) {
58 __raw_writel((LCD_SETDDRAM | i),
59 (display + DISPLAY_LCDINSTRUCTION));
61 __raw_writel(ch, display + DISPLAY_LCDDATA);
65 static void scroll_display_message(unsigned long data)
67 mips_display_message(&display_string[display_count++]);
68 if (display_count == max_display_count)
70 mod_timer(&mips_scroll_timer, jiffies + HZ);
73 void mips_scroll_message(void)
75 del_timer_sync(&mips_scroll_timer);
76 max_display_count = strlen(display_string) + 1 - 16;
77 mod_timer(&mips_scroll_timer, jiffies + 1);