/* * Driver for the LCD display on the Tensilica XTFPGA board family. * http://www.mytechcorp.com/cfdata/productFile/File1/MOC-16216B-B-A0A04.pdf * * This file is subject to the terms and conditions of the GNU General Public * License. See the file "COPYING" in the main directory of this archive * for more details. * * Copyright (C) 2001, 2006 Tensilica Inc. * Copyright (C) 2015 Cadence Design Systems Inc. */ #include <linux/delay.h> #include <linux/init.h> #include <linux/io.h> #include <platform/hardware.h> #include <platform/lcd.h> /* LCD instruction and data addresses. */ #define LCD_INSTR_ADDR ((char *)IOADDR(CONFIG_XTFPGA_LCD_BASE_ADDR)) #define LCD_DATA_ADDR (LCD_INSTR_ADDR + 4) #define LCD_CLEAR 0x1 #define LCD_DISPLAY_ON 0xc /* 8bit and 2 lines display */ #define LCD_DISPLAY_MODE8BIT 0x38 #define LCD_DISPLAY_MODE4BIT 0x28 #define LCD_DISPLAY_POS 0x80 #define LCD_SHIFT_LEFT 0x18 #define LCD_SHIFT_RIGHT 0x1c static void lcd_put_byte(u8 *addr, u8 data) { #ifdef CONFIG_XTFPGA_LCD_8BIT_ACCESS WRITE_ONCE(*addr, data); #else WRITE_ONCE(*addr, data & 0xf0); WRITE_ONCE(*addr, (data << 4) & 0xf0); #endif } static int __init lcd_init(void) { WRITE_ONCE(*LCD_INSTR_ADDR, LCD_DISPLAY_MODE8BIT); mdelay(5); WRITE_ONCE(*LCD_INSTR_ADDR, LCD_DISPLAY_MODE8BIT); udelay(200); WRITE_ONCE(*LCD_INSTR_ADDR, LCD_DISPLAY_MODE8BIT); udelay(50); #ifndef CONFIG_XTFPGA_LCD_8BIT_ACCESS WRITE_ONCE(*LCD_INSTR_ADDR, LCD_DISPLAY_MODE4BIT); udelay(50); lcd_put_byte(LCD_INSTR_ADDR, LCD_DISPLAY_MODE4BIT); udelay(50); #endif lcd_put_byte(LCD_INSTR_ADDR, LCD_DISPLAY_ON); udelay(50); lcd_put_byte(LCD_INSTR_ADDR, LCD_CLEAR); mdelay(10); lcd_disp_at_pos("XTENSA LINUX", 0); return 0; } void lcd_disp_at_pos(char *str, unsigned char pos) { lcd_put_byte(LCD_INSTR_ADDR, LCD_DISPLAY_POS | pos); udelay(100); while (*str != 0) { lcd_put_byte(LCD_DATA_ADDR, *str); udelay(200); str++; } } void lcd_shiftleft(void) { lcd_put_byte(LCD_INSTR_ADDR, LCD_SHIFT_LEFT); udelay(50); } void lcd_shiftright(void) { lcd_put_byte(LCD_INSTR_ADDR, LCD_SHIFT_RIGHT); udelay(50); } arch_initcall(lcd_init);