[uboot] create uboot from github:

repo: https://github.com/u-boot/u-boot
	commit: d80bb749fab53da72c4a0e09b8c2d2aaa3103c91

Change-Id: Ie6434426e1ec15bc08bb1832798e371f3fd5fb29

u-boot-2021.10/arch/arm/lib/stack.c

@@ -0,0 +1,35 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (c) 2015 Andreas Bießmann <andreas@biessmann.org>
+ *
+ * Copyright (c) 2011 The Chromium OS Authors.
+ * (C) Copyright 2002-2006
+ * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
+ *
+ * (C) Copyright 2002
+ * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
+ * Marius Groeger <mgroeger@sysgo.de>
+ */
+#include <common.h>
+#include <init.h>
+#include <asm/global_data.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+int arch_reserve_stacks(void)
+{
+#ifdef CONFIG_SPL_BUILD
+	gd->start_addr_sp -= 128;	/* leave 32 words for abort-stack */
+	gd->irq_sp = gd->start_addr_sp;
+#else
+	/* setup stack pointer for exceptions */
+	gd->irq_sp = gd->start_addr_sp;
+
+# if !defined(CONFIG_ARM64)
+	/* leave 3 words for abort-stack, plus 1 for alignment */
+	gd->start_addr_sp -= 16;
+# endif
+#endif
+
+	return 0;
+}