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authorMax Filippov <jcmvbkbc@gmail.com>2012-11-05 07:37:14 +0400
committerChris Zankel <chris@zankel.net>2012-12-18 21:10:24 -0800
commit0d456bad36d42d16022be045c8a53ddbb59ee478 (patch)
tree3c135bfcf37d6ccf45fd9ac4f739df95e181d416 /arch/xtensa/platforms/xtfpga/lcd.c
parentda844a81779e2bb263eca4ecb1046541fdb11cf8 (diff)
xtensa: add support for the XTFPGA boards
The Avnet LX60/LX110/LX200 board is an FPGA board that can be configured with an Xtensa processor and an OpenCores Ethernet device. Signed-off-by: Chris Zankel <chris@zankel.net> Signed-off-by: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: Chris Zankel <chris@zankel.net>
Diffstat (limited to 'arch/xtensa/platforms/xtfpga/lcd.c')
-rw-r--r--arch/xtensa/platforms/xtfpga/lcd.c76
1 files changed, 76 insertions, 0 deletions
diff --git a/arch/xtensa/platforms/xtfpga/lcd.c b/arch/xtensa/platforms/xtfpga/lcd.c
new file mode 100644
index 000000000000..2872301598df
--- /dev/null
+++ b/arch/xtensa/platforms/xtfpga/lcd.c
@@ -0,0 +1,76 @@
+/*
+ * Driver for the LCD display on the Tensilica LX60 Board.
+ *
+ * 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.
+ */
+
+/*
+ *
+ * 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/init.h>
+#include <linux/io.h>
+
+#include <platform/hardware.h>
+#include <platform/lcd.h>
+#include <linux/delay.h>
+
+#define LCD_PAUSE_ITERATIONS 4000
+#define LCD_CLEAR 0x1
+#define LCD_DISPLAY_ON 0xc
+
+/* 8bit and 2 lines display */
+#define LCD_DISPLAY_MODE8BIT 0x38
+#define LCD_DISPLAY_POS 0x80
+#define LCD_SHIFT_LEFT 0x18
+#define LCD_SHIFT_RIGHT 0x1c
+
+static int __init lcd_init(void)
+{
+ *LCD_INSTR_ADDR = LCD_DISPLAY_MODE8BIT;
+ mdelay(5);
+ *LCD_INSTR_ADDR = LCD_DISPLAY_MODE8BIT;
+ udelay(200);
+ *LCD_INSTR_ADDR = LCD_DISPLAY_MODE8BIT;
+ udelay(50);
+ *LCD_INSTR_ADDR = LCD_DISPLAY_ON;
+ udelay(50);
+ *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_INSTR_ADDR = LCD_DISPLAY_POS | pos;
+ udelay(100);
+ while (*str != 0) {
+ *LCD_DATA_ADDR = *str;
+ udelay(200);
+ str++;
+ }
+}
+
+void lcd_shiftleft(void)
+{
+ *LCD_INSTR_ADDR = LCD_SHIFT_LEFT;
+ udelay(50);
+}
+
+void lcd_shiftright(void)
+{
+ *LCD_INSTR_ADDR = LCD_SHIFT_RIGHT;
+ udelay(50);
+}
+
+arch_initcall(lcd_init);