diff options
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/xtensa/Kconfig | 30 | ||||
| -rw-r--r-- | arch/xtensa/platforms/xtfpga/Makefile | 3 | ||||
| -rw-r--r-- | arch/xtensa/platforms/xtfpga/include/platform/hardware.h | 3 | ||||
| -rw-r--r-- | arch/xtensa/platforms/xtfpga/include/platform/lcd.h | 15 | ||||
| -rw-r--r-- | arch/xtensa/platforms/xtfpga/lcd.c | 55 |
5 files changed, 81 insertions, 25 deletions
diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig index 0a1b95f81a32..2b086a6ae6c7 100644 --- a/arch/xtensa/Kconfig +++ b/arch/xtensa/Kconfig @@ -287,6 +287,36 @@ menu "Executable file formats" source "fs/Kconfig.binfmt" +config XTFPGA_LCD + bool "Enable XTFPGA LCD driver" + depends on XTENSA_PLATFORM_XTFPGA + default n + help + There's a 2x16 LCD on most of XTFPGA boards, kernel may output + progress messages there during bootup/shutdown. It may be useful + during board bringup. + + If unsure, say N. + +config XTFPGA_LCD_BASE_ADDR + hex "XTFPGA LCD base address" + depends on XTFPGA_LCD + default "0x0d0c0000" + help + Base address of the LCD controller inside KIO region. + Different boards from XTFPGA family have LCD controller at different + addresses. Please consult prototyping user guide for your board for + the correct address. Wrong address here may lead to hardware lockup. + +config XTFPGA_LCD_8BIT_ACCESS + bool "Use 8-bit access to XTFPGA LCD" + depends on XTFPGA_LCD + default n + help + LCD may be connected with 4- or 8-bit interface, 8-bit access may + only be used with 8-bit interface. Please consult prototyping user + guide for your board for the correct interface width. + endmenu source "net/Kconfig" diff --git a/arch/xtensa/platforms/xtfpga/Makefile b/arch/xtensa/platforms/xtfpga/Makefile index b9ae206340cd..7839d38b2337 100644 --- a/arch/xtensa/platforms/xtfpga/Makefile +++ b/arch/xtensa/platforms/xtfpga/Makefile @@ -6,4 +6,5 @@ # # Note 2! The CFLAGS definitions are in the main makefile... -obj-y = setup.o lcd.o +obj-y += setup.o +obj-$(CONFIG_XTFPGA_LCD) += lcd.o diff --git a/arch/xtensa/platforms/xtfpga/include/platform/hardware.h b/arch/xtensa/platforms/xtfpga/include/platform/hardware.h index 4416773cbde5..b39fbcf5c611 100644 --- a/arch/xtensa/platforms/xtfpga/include/platform/hardware.h +++ b/arch/xtensa/platforms/xtfpga/include/platform/hardware.h @@ -44,9 +44,6 @@ /* UART */ #define DUART16552_PADDR (XCHAL_KIO_PADDR + 0x0D050020) -/* LCD instruction and data addresses. */ -#define LCD_INSTR_ADDR ((char *)IOADDR(0x0D040000)) -#define LCD_DATA_ADDR ((char *)IOADDR(0x0D040004)) /* Misc. */ #define XTFPGA_FPGAREGS_VADDR IOADDR(0x0D020000) diff --git a/arch/xtensa/platforms/xtfpga/include/platform/lcd.h b/arch/xtensa/platforms/xtfpga/include/platform/lcd.h index 0e435645af5a..4c8541ed1139 100644 --- a/arch/xtensa/platforms/xtfpga/include/platform/lcd.h +++ b/arch/xtensa/platforms/xtfpga/include/platform/lcd.h @@ -11,10 +11,25 @@ #ifndef __XTENSA_XTAVNET_LCD_H #define __XTENSA_XTAVNET_LCD_H +#ifdef CONFIG_XTFPGA_LCD /* Display string STR at position POS on the LCD. */ void lcd_disp_at_pos(char *str, unsigned char pos); /* Shift the contents of the LCD display left or right. */ void lcd_shiftleft(void); void lcd_shiftright(void); +#else +static inline void lcd_disp_at_pos(char *str, unsigned char pos) +{ +} + +static inline void lcd_shiftleft(void) +{ +} + +static inline void lcd_shiftright(void) +{ +} +#endif + #endif diff --git a/arch/xtensa/platforms/xtfpga/lcd.c b/arch/xtensa/platforms/xtfpga/lcd.c index 2872301598df..4dc0c1b43f4b 100644 --- a/arch/xtensa/platforms/xtfpga/lcd.c +++ b/arch/xtensa/platforms/xtfpga/lcd.c @@ -1,50 +1,63 @@ /* - * Driver for the LCD display on the Tensilica LX60 Board. + * 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. */ -/* - * - * FIXME: this code is from the examples from the LX60 user guide. - * - * The lcd_pause function does busy waiting, which is probably not - * great. Maybe the code could be changed to use kernel timers, or - * change the hardware to not need to wait. - */ - +#include <linux/delay.h> #include <linux/init.h> #include <linux/io.h> #include <platform/hardware.h> #include <platform/lcd.h> -#include <linux/delay.h> -#define LCD_PAUSE_ITERATIONS 4000 +/* 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 + ACCESS_ONCE(*addr) = data; +#else + ACCESS_ONCE(*addr) = data & 0xf0; + ACCESS_ONCE(*addr) = (data << 4) & 0xf0; +#endif +} + static int __init lcd_init(void) { - *LCD_INSTR_ADDR = LCD_DISPLAY_MODE8BIT; + ACCESS_ONCE(*LCD_INSTR_ADDR) = LCD_DISPLAY_MODE8BIT; mdelay(5); - *LCD_INSTR_ADDR = LCD_DISPLAY_MODE8BIT; + ACCESS_ONCE(*LCD_INSTR_ADDR) = LCD_DISPLAY_MODE8BIT; udelay(200); - *LCD_INSTR_ADDR = LCD_DISPLAY_MODE8BIT; + ACCESS_ONCE(*LCD_INSTR_ADDR) = LCD_DISPLAY_MODE8BIT; + udelay(50); +#ifndef CONFIG_XTFPGA_LCD_8BIT_ACCESS + ACCESS_ONCE(*LCD_INSTR_ADDR) = LCD_DISPLAY_MODE4BIT; + udelay(50); + lcd_put_byte(LCD_INSTR_ADDR, LCD_DISPLAY_MODE4BIT); udelay(50); - *LCD_INSTR_ADDR = LCD_DISPLAY_ON; +#endif + lcd_put_byte(LCD_INSTR_ADDR, LCD_DISPLAY_ON); udelay(50); - *LCD_INSTR_ADDR = LCD_CLEAR; + lcd_put_byte(LCD_INSTR_ADDR, LCD_CLEAR); mdelay(10); lcd_disp_at_pos("XTENSA LINUX", 0); return 0; @@ -52,10 +65,10 @@ static int __init lcd_init(void) void lcd_disp_at_pos(char *str, unsigned char pos) { - *LCD_INSTR_ADDR = LCD_DISPLAY_POS | pos; + lcd_put_byte(LCD_INSTR_ADDR, LCD_DISPLAY_POS | pos); udelay(100); while (*str != 0) { - *LCD_DATA_ADDR = *str; + lcd_put_byte(LCD_DATA_ADDR, *str); udelay(200); str++; } @@ -63,13 +76,13 @@ void lcd_disp_at_pos(char *str, unsigned char pos) void lcd_shiftleft(void) { - *LCD_INSTR_ADDR = LCD_SHIFT_LEFT; + lcd_put_byte(LCD_INSTR_ADDR, LCD_SHIFT_LEFT); udelay(50); } void lcd_shiftright(void) { - *LCD_INSTR_ADDR = LCD_SHIFT_RIGHT; + lcd_put_byte(LCD_INSTR_ADDR, LCD_SHIFT_RIGHT); udelay(50); } |