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/drivers/rtc/mx27rtc.c

@@ -0,0 +1,69 @@
+/*
+ * Freescale i.MX27 RTC Driver
+ *
+ * Copyright (C) 2012 Philippe Reynes <tremyfr@yahoo.fr>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <rtc.h>
+#include <asm/io.h>
+#include <asm/arch/imx-regs.h>
+
+#define HOUR_SHIFT 8
+#define HOUR_MASK  0x1f
+#define MIN_SHIFT  0
+#define MIN_MASK   0x3f
+
+int rtc_get(struct rtc_time *time)
+{
+	struct rtc_regs *rtc_regs = (struct rtc_regs *)IMX_RTC_BASE;
+	uint32_t day, hour, min, sec;
+
+	day  = readl(&rtc_regs->dayr);
+	hour = readl(&rtc_regs->hourmin);
+	sec  = readl(&rtc_regs->seconds);
+
+	min  = (hour >> MIN_SHIFT) & MIN_MASK;
+	hour = (hour >> HOUR_SHIFT) & HOUR_MASK;
+
+	sec += min * 60 + hour * 3600 + day * 24 * 3600;
+
+	rtc_to_tm(sec, time);
+
+	return 0;
+}
+
+int rtc_set(struct rtc_time *time)
+{
+	struct rtc_regs *rtc_regs = (struct rtc_regs *)IMX_RTC_BASE;
+	uint32_t day, hour, min, sec;
+
+	sec = rtc_mktime(time);
+
+	day  = sec / (24 * 3600);
+	sec  = sec % (24 * 3600);
+	hour = sec / 3600;
+	sec  = sec % 3600;
+	min  = sec / 60;
+	sec  = sec % 60;
+
+	hour  = (hour & HOUR_MASK) << HOUR_SHIFT;
+	hour |= (min & MIN_MASK) << MIN_SHIFT;
+
+	writel(day, &rtc_regs->dayr);
+	writel(hour, &rtc_regs->hourmin);
+	writel(sec, &rtc_regs->seconds);
+
+	return 0;
+}
+
+void rtc_reset(void)
+{
+	struct rtc_regs *rtc_regs = (struct rtc_regs *)IMX_RTC_BASE;
+
+	writel(0, &rtc_regs->dayr);
+	writel(0, &rtc_regs->hourmin);
+	writel(0, &rtc_regs->seconds);
+}