avionic design with actual uboot and tooling

submodule of avionic design uboot bootloader and with included tools to
get you started , read readme.md and readme-tk1-loader.md

u-boot/arch/arm/cpu/arm920t/ep93xx/led.c

@@ -0,0 +1,85 @@
+/*
+ * Copyright (C) 2010, 2009 Matthias Kaehlcke <matthias@kaehlcke.net>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <asm/io.h>
+#include <asm/arch/ep93xx.h>
+#include <config.h>
+#include <status_led.h>
+
+static uint8_t saved_state[2] = {STATUS_LED_OFF, STATUS_LED_OFF};
+static uint32_t gpio_pin[2] = {1 << STATUS_LED_GREEN,
+			       1 << STATUS_LED_RED};
+
+static inline void switch_LED_on(uint8_t led)
+{
+	register struct gpio_regs *gpio = (struct gpio_regs *)GPIO_BASE;
+
+	writel(readl(&gpio->pedr) | gpio_pin[led], &gpio->pedr);
+	saved_state[led] = STATUS_LED_ON;
+}
+
+static inline void switch_LED_off(uint8_t led)
+{
+	register struct gpio_regs *gpio = (struct gpio_regs *)GPIO_BASE;
+
+	writel(readl(&gpio->pedr) & ~gpio_pin[led], &gpio->pedr);
+	saved_state[led] = STATUS_LED_OFF;
+}
+
+void red_led_on(void)
+{
+	switch_LED_on(STATUS_LED_RED);
+}
+
+void red_led_off(void)
+{
+	switch_LED_off(STATUS_LED_RED);
+}
+
+void green_led_on(void)
+{
+	switch_LED_on(STATUS_LED_GREEN);
+}
+
+void green_led_off(void)
+{
+	switch_LED_off(STATUS_LED_GREEN);
+}
+
+void __led_init(led_id_t mask, int state)
+{
+	__led_set(mask, state);
+}
+
+void __led_toggle(led_id_t mask)
+{
+	if (STATUS_LED_RED == mask) {
+		if (STATUS_LED_ON == saved_state[STATUS_LED_RED])
+			red_led_off();
+		else
+			red_led_on();
+	} else if (STATUS_LED_GREEN == mask) {
+		if (STATUS_LED_ON == saved_state[STATUS_LED_GREEN])
+			green_led_off();
+		else
+			green_led_on();
+	}
+}
+
+void __led_set(led_id_t mask, int state)
+{
+	if (STATUS_LED_RED == mask) {
+		if (STATUS_LED_ON == state)
+			red_led_on();
+		else
+			red_led_off();
+	} else if (STATUS_LED_GREEN == mask) {
+		if (STATUS_LED_ON == state)
+			green_led_on();
+		else
+			green_led_off();
+	}
+}