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/lib/interrupts_m.c

@@ -0,0 +1,95 @@
+/*
+ * (C) Copyright 2015
+ * Kamil Lulko, <kamil.lulko@gmail.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+
+/*
+ * Upon exception entry ARMv7-M processors automatically save stack
+ * frames containing some registers. For simplicity initial
+ * implementation uses only this auto-saved stack frame.
+ * This does not contain complete register set dump,
+ * only R0-R3, R12, LR, PC and xPSR are saved.
+ */
+
+struct autosave_regs {
+	long uregs[8];
+};
+
+#define ARM_XPSR	uregs[7]
+#define ARM_PC		uregs[6]
+#define ARM_LR		uregs[5]
+#define ARM_R12		uregs[4]
+#define ARM_R3		uregs[3]
+#define ARM_R2		uregs[2]
+#define ARM_R1		uregs[1]
+#define ARM_R0		uregs[0]
+
+int interrupt_init(void)
+{
+	return 0;
+}
+
+void enable_interrupts(void)
+{
+	return;
+}
+
+int disable_interrupts(void)
+{
+	return 0;
+}
+
+void dump_regs(struct autosave_regs *regs)
+{
+	printf("pc : %08lx    lr : %08lx    xPSR : %08lx\n",
+	       regs->ARM_PC, regs->ARM_LR, regs->ARM_XPSR);
+	printf("r12 : %08lx   r3 : %08lx    r2 : %08lx\n"
+		"r1 : %08lx    r0 : %08lx\n",
+		regs->ARM_R12, regs->ARM_R3, regs->ARM_R2,
+		regs->ARM_R1, regs->ARM_R0);
+}
+
+void bad_mode(void)
+{
+	panic("Resetting CPU ...\n");
+	reset_cpu(0);
+}
+
+void do_hard_fault(struct autosave_regs *autosave_regs)
+{
+	printf("Hard fault\n");
+	dump_regs(autosave_regs);
+	bad_mode();
+}
+
+void do_mm_fault(struct autosave_regs *autosave_regs)
+{
+	printf("Memory management fault\n");
+	dump_regs(autosave_regs);
+	bad_mode();
+}
+
+void do_bus_fault(struct autosave_regs *autosave_regs)
+{
+	printf("Bus fault\n");
+	dump_regs(autosave_regs);
+	bad_mode();
+}
+
+void do_usage_fault(struct autosave_regs *autosave_regs)
+{
+	printf("Usage fault\n");
+	dump_regs(autosave_regs);
+	bad_mode();
+}
+
+void do_invalid_entry(struct autosave_regs *autosave_regs)
+{
+	printf("Exception\n");
+	dump_regs(autosave_regs);
+	bad_mode();
+}