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) 2012 MIPS Technologies, Inc. All rights reserved. 7 */ 8 #include <linux/timer.h> 9 #include <linux/io.h> 10 #include <asm/mips-boards/generic.h> 11 12 static unsigned int display_count; 13 static unsigned int max_display_count; 14 15 #define LCD_DISPLAY_POS_BASE 0x1f000400 16 #define DISPLAY_LCDINSTRUCTION (0*2) 17 #define DISPLAY_LCDDATA (1*2) 18 #define DISPLAY_CPLDSTATUS (2*2) 19 #define DISPLAY_CPLDDATA (3*2) 20 #define LCD_SETDDRAM 0x80 21 #define LCD_IR_BF 0x80 22 23 const char display_string[] = " LINUX ON SEAD3 "; 24 25 static void scroll_display_message(unsigned long data); 26 static DEFINE_TIMER(mips_scroll_timer, scroll_display_message, HZ, 0); 27 lcd_wait(unsigned int __iomem * display)28static void lcd_wait(unsigned int __iomem *display) 29 { 30 /* Wait for CPLD state machine to become idle. */ 31 do { } while (__raw_readl(display + DISPLAY_CPLDSTATUS) & 1); 32 33 do { 34 __raw_readl(display + DISPLAY_LCDINSTRUCTION); 35 36 /* Wait for CPLD state machine to become idle. */ 37 do { } while (__raw_readl(display + DISPLAY_CPLDSTATUS) & 1); 38 } while (__raw_readl(display + DISPLAY_CPLDDATA) & LCD_IR_BF); 39 } 40 mips_display_message(const char * str)41void mips_display_message(const char *str) 42 { 43 static unsigned int __iomem *display; 44 char ch; 45 int i; 46 47 if (unlikely(display == NULL)) 48 display = ioremap_nocache(LCD_DISPLAY_POS_BASE, 49 (8 * sizeof(int))); 50 51 for (i = 0; i < 16; i++) { 52 if (*str) 53 ch = *str++; 54 else 55 ch = ' '; 56 lcd_wait(display); 57 __raw_writel((LCD_SETDDRAM | i), 58 (display + DISPLAY_LCDINSTRUCTION)); 59 lcd_wait(display); 60 __raw_writel(ch, display + DISPLAY_LCDDATA); 61 } 62 } 63 scroll_display_message(unsigned long data)64static void scroll_display_message(unsigned long data) 65 { 66 mips_display_message(&display_string[display_count++]); 67 if (display_count == max_display_count) 68 display_count = 0; 69 mod_timer(&mips_scroll_timer, jiffies + HZ); 70 } 71 mips_scroll_message(void)72void mips_scroll_message(void) 73 { 74 del_timer_sync(&mips_scroll_timer); 75 max_display_count = strlen(display_string) + 1 - 16; 76 mod_timer(&mips_scroll_timer, jiffies + 1); 77 } 78