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#include <asm/mips-boards/prom.h> 12 13static unsigned int display_count; 14static unsigned int max_display_count; 15 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 23 24const char display_string[] = " LINUX ON SEAD3 "; 25 26static void scroll_display_message(unsigned long data); 27static DEFINE_TIMER(mips_scroll_timer, scroll_display_message, HZ, 0); 28 29static void lcd_wait(unsigned int __iomem *display) 30{ 31 /* Wait for CPLD state machine to become idle. */ 32 do { } while (__raw_readl(display + DISPLAY_CPLDSTATUS) & 1); 33 34 do { 35 __raw_readl(display + DISPLAY_LCDINSTRUCTION); 36 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); 40} 41 42void mips_display_message(const char *str) 43{ 44 static unsigned int __iomem *display; 45 char ch; 46 int i; 47 48 if (unlikely(display == NULL)) 49 display = ioremap_nocache(LCD_DISPLAY_POS_BASE, 50 (8 * sizeof(int))); 51 52 for (i = 0; i < 16; i++) { 53 if (*str) 54 ch = *str++; 55 else 56 ch = ' '; 57 lcd_wait(display); 58 __raw_writel((LCD_SETDDRAM | i), 59 (display + DISPLAY_LCDINSTRUCTION)); 60 lcd_wait(display); 61 __raw_writel(ch, display + DISPLAY_LCDDATA); 62 } 63} 64 65static void scroll_display_message(unsigned long data) 66{ 67 mips_display_message(&display_string[display_count++]); 68 if (display_count == max_display_count) 69 display_count = 0; 70 mod_timer(&mips_scroll_timer, jiffies + HZ); 71} 72 73void mips_scroll_message(void) 74{ 75 del_timer_sync(&mips_scroll_timer); 76 max_display_count = strlen(display_string) + 1 - 16; 77 mod_timer(&mips_scroll_timer, jiffies + 1); 78} 79