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/blackfin/cpu/reset.c

@@ -0,0 +1,96 @@
+/*
+ * reset.c - logic for resetting the cpu
+ *
+ * Copyright (c) 2005-2008 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2 or later.
+ */
+
+#include <common.h>
+#include <command.h>
+#include <asm/blackfin.h>
+#include <asm/mach-common/bits/bootrom.h>
+#include "cpu.h"
+
+/* A system soft reset makes external memory unusable so force
+ * this function into L1.  We use the compiler ssync here rather
+ * than SSYNC() because it's safe (no interrupts and such) and
+ * we save some L1.  We do not need to force sanity in the SYSCR
+ * register as the BMODE selection bit is cleared by the soft
+ * reset while the Core B bit (on dual core parts) is cleared by
+ * the core reset.
+ */
+__attribute__ ((__l1_text__, __noreturn__))
+static void bfin_reset(void)
+{
+#ifdef SWRST
+	/* Wait for completion of "system" events such as cache line
+	 * line fills so that we avoid infinite stalls later on as
+	 * much as possible.  This code is in L1, so it won't trigger
+	 * any such event after this point in time.
+	 */
+	__builtin_bfin_ssync();
+
+	/* Initiate System software reset. */
+	bfin_write_SWRST(0x7);
+
+	/* Due to the way reset is handled in the hardware, we need
+	 * to delay for 10 SCLKS.  The only reliable way to do this is
+	 * to calculate the CCLK/SCLK ratio and multiply 10.  For now,
+	 * we'll assume worse case which is a 1:15 ratio.
+	 */
+	asm(
+		"LSETUP (1f, 1f) LC0 = %0\n"
+		"1: nop;"
+		:
+		: "a" (15 * 10)
+		: "LC0", "LB0", "LT0"
+	);
+
+	/* Clear System software reset */
+	bfin_write_SWRST(0);
+
+	/* The BF526 ROM will crash during reset */
+#if defined(__ADSPBF522__) || defined(__ADSPBF524__) || defined(__ADSPBF526__)
+	/* Seems to be fixed with newer parts though ... */
+	if (__SILICON_REVISION__ < 1 && bfin_revid() < 1)
+		bfin_read_SWRST();
+#endif
+
+	/* Wait for the SWRST write to complete.  Cannot rely on SSYNC
+	 * though as the System state is all reset now.
+	 */
+	asm(
+		"LSETUP (1f, 1f) LC1 = %0\n"
+		"1: nop;"
+		:
+		: "a" (15 * 1)
+		: "LC1", "LB1", "LT1"
+	);
+#endif
+
+	while (1)
+#if defined(__ADSPBF60x__)
+		bfin_write_RCU0_CTL(0x1);
+#else
+		/* Issue core reset */
+		asm("raise 1");
+#endif
+}
+
+/* We need to trampoline ourselves up into L1 since our linker
+ * does not have relaxtion support and will only generate a
+ * PC relative call with a 25 bit immediate.  This is not enough
+ * to get us from the top of SDRAM into L1.
+ */
+int do_reset(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
+{
+	if (board_reset)
+		board_reset();
+	if (ANOMALY_05000353 || ANOMALY_05000386)
+		while (1)
+			asm("jump (%0);" : : "a" (bfin_reset));
+	else
+		bfrom_SoftReset((void *)(L1_SRAM_SCRATCH_END - 20));
+	return 0;
+}