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/mach-at91/arm926ejs/cpu.c

@@ -0,0 +1,56 @@
+/*
+ * (C) Copyright 2010
+ * Reinhard Meyer, reinhard.meyer@emk-elektronik.de
+ * (C) Copyright 2009
+ * Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <asm/arch/hardware.h>
+#include <asm/arch/at91_pit.h>
+#include <asm/arch/at91_gpbr.h>
+#include <asm/arch/clk.h>
+
+#ifndef CONFIG_SYS_AT91_MAIN_CLOCK
+#define CONFIG_SYS_AT91_MAIN_CLOCK 0
+#endif
+
+int arch_cpu_init(void)
+{
+	return at91_clock_init(CONFIG_SYS_AT91_MAIN_CLOCK);
+}
+
+void arch_preboot_os(void)
+{
+	ulong cpiv;
+	at91_pit_t *pit = (at91_pit_t *) ATMEL_BASE_PIT;
+
+	cpiv = AT91_PIT_MR_PIV_MASK(readl(&pit->piir));
+
+	/*
+	 * Disable PITC
+	 * Add 0x1000 to current counter to stop it faster
+	 * without waiting for wrapping back to 0
+	 */
+	writel(cpiv + 0x1000, &pit->mr);
+}
+
+#if defined(CONFIG_DISPLAY_CPUINFO)
+int print_cpuinfo(void)
+{
+	char __maybe_unused buf[32];
+
+	printf("CPU: %s\n", ATMEL_CPU_NAME);
+	printf("Crystal frequency: %8s MHz\n",
+					strmhz(buf, get_main_clk_rate()));
+	printf("CPU clock        : %8s MHz\n",
+					strmhz(buf, get_cpu_clk_rate()));
+	printf("Master clock     : %8s MHz\n",
+					strmhz(buf, get_mck_clk_rate()));
+
+	return 0;
+}
+#endif