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/post/cpu/ppc4xx/uart.c

@@ -0,0 +1,92 @@
+/*
+ * (C) Copyright 2007
+ * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
+ *
+ * Author: Igor Lisitsin <igor@emcraft.com>
+ *
+ * Copyright 2010, Stefan Roese, DENX Software Engineering, sr@denx.de
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <asm/ppc4xx.h>
+#include <ns16550.h>
+#include <asm/io.h>
+#include <serial.h>
+
+/*
+ * UART test
+ *
+ * The controllers are configured to loopback mode and several
+ * characters are transmitted.
+ */
+
+#include <post.h>
+
+#if CONFIG_POST & CONFIG_SYS_POST_UART
+
+/*
+ * This table defines the UART's that should be tested and can
+ * be overridden in the board config file
+ */
+#ifndef CONFIG_SYS_POST_UART_TABLE
+#define CONFIG_SYS_POST_UART_TABLE	{ CONFIG_SYS_NS16550_COM1, \
+			CONFIG_SYS_NS16550_COM2, CONFIG_SYS_NS16550_COM3, \
+			CONFIG_SYS_NS16550_COM4	}
+#endif
+
+DECLARE_GLOBAL_DATA_PTR;
+
+static int test_ctlr (struct NS16550 *com_port, int index)
+{
+	int res = -1;
+	char test_str[] = "*** UART Test String ***\r\n";
+	int i;
+	int divisor;
+
+	divisor = (get_serial_clock() + (gd->baudrate * (16 / 2))) /
+		(16 * gd->baudrate);
+	NS16550_init(com_port, divisor);
+
+	/*
+	 * Set internal loopback mode in UART
+	 */
+	out_8(&com_port->mcr, in_8(&com_port->mcr) | UART_MCR_LOOP);
+
+	/* Reset FIFOs */
+	out_8(&com_port->fcr, UART_FCR_RXSR | UART_FCR_TXSR);
+	udelay(100);
+
+	/* Flush RX-FIFO */
+	while (NS16550_tstc(com_port))
+		NS16550_getc(com_port);
+
+	for (i = 0; i < sizeof (test_str) - 1; i++) {
+		NS16550_putc(com_port, test_str[i]);
+		if (NS16550_getc(com_port) != test_str[i])
+			goto done;
+	}
+	res = 0;
+done:
+	if (res)
+		post_log ("uart%d test failed\n", index);
+
+	return res;
+}
+
+int uart_post_test (int flags)
+{
+	int i, res = 0;
+	static unsigned long base[] = CONFIG_SYS_POST_UART_TABLE;
+
+	for (i = 0; i < ARRAY_SIZE(base); i++) {
+		if (test_ctlr((struct NS16550 *)base[i], i))
+			res = -1;
+	}
+	serial_reinit_all ();
+
+	return res;
+}
+
+#endif /* CONFIG_POST & CONFIG_SYS_POST_UART */