GK SDK 源码库: XMIPCLinuxV100R005C00SPC030 (kernel/tools/open_source excluded)

source/bootloader/u-boot-2020.01/arch/arm/cpu/armv7m/cpu.c

@@ -0,0 +1,58 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * (C) Copyright 2010,2011
+ * Vladimir Khusainov, Emcraft Systems, vlad@emcraft.com
+ *
+ * (C) Copyright 2015
+ * Kamil Lulko, <kamil.lulko@gmail.com>
+ */
+
+#include <common.h>
+#include <cpu_func.h>
+#include <irq_func.h>
+#include <asm/io.h>
+#include <asm/armv7m.h>
+
+/*
+ * This is called right before passing control to
+ * the Linux kernel point.
+ */
+int cleanup_before_linux(void)
+{
+	/*
+	 * this function is called just before we call linux
+	 * it prepares the processor for linux
+	 *
+	 * disable interrupt and turn off caches etc ...
+	 */
+	disable_interrupts();
+	/*
+	 * turn off D-cache
+	 * dcache_disable() in turn flushes the d-cache
+	 * MPU is still enabled & can't be disabled as the u-boot
+	 * code might be running in sdram which by default is not
+	 * executable area.
+	 */
+	dcache_disable();
+	/* invalidate to make sure no cache line gets dirty between
+	 * dcache flushing and disabling dcache */
+	invalidate_dcache_all();
+
+	icache_disable();
+	invalidate_icache_all();
+
+	return 0;
+}
+
+/*
+ * Perform the low-level reset.
+ */
+void reset_cpu(ulong addr)
+{
+	/*
+	 * Perform reset but keep priority group unchanged.
+	 */
+	writel((V7M_AIRCR_VECTKEY << V7M_AIRCR_VECTKEY_SHIFT)
+		| (V7M_SCB->aircr & V7M_AIRCR_PRIGROUP_MSK)
+		| V7M_AIRCR_SYSRESET, &V7M_SCB->aircr);
+}