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/powerpc/lib/_ashrdi3.S

@@ -0,0 +1,44 @@
+/*
+ * This code was copied from arch/powerpc/kernel/misc_32.S in the Linux
+ * kernel sources (commit 85e2efbb1db9a18d218006706d6e4fbeb0216213, also
+ * known as 2.6.38-rc5).  The source file copyrights are as follows:
+ *
+ * (C) Copyright 1995-1996 Gary Thomas (gdt@linuxppc.org)
+ *
+ * Largely rewritten by Cort Dougan (cort@cs.nmt.edu)
+ * and Paul Mackerras.
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <ppc_asm.tmpl>
+#include <ppc_defs.h>
+#include <config.h>
+
+/*
+ * Extended precision shifts.
+ *
+ * Updated to be valid for shift counts from 0 to 63 inclusive.
+ * -- Gabriel
+ *
+ * R3/R4 has 64 bit value
+ * R5    has shift count
+ * result in R3/R4
+ *
+ *  ashrdi3: arithmetic right shift (sign propagation)
+ *  lshrdi3: logical right shift
+ *  ashldi3: left shift
+ */
+	.globl __ashrdi3
+__ashrdi3:
+	subfic	r6,r5,32
+	srw	r4,r4,r5	# LSW = count > 31 ? 0 : LSW >> count
+	addi	r7,r5,32	# could be xori, or addi with -32
+	slw	r6,r3,r6	# t1 = count > 31 ? 0 : MSW << (32-count)
+	rlwinm	r8,r7,0,32	# t3 = (count < 32) ? 32 : 0
+	sraw	r7,r3,r7	# t2 = MSW >> (count-32)
+	or	r4,r4,r6	# LSW |= t1
+	slw	r7,r7,r8	# t2 = (count < 32) ? 0 : t2
+	sraw	r3,r3,r5	# MSW = MSW >> count
+	or	r4,r4,r7	# LSW |= t2
+	blr