reboot: add reboot infrastructure

Add the REBOOT kconfig option, along with the sys_reboot() API.

This infrastructure is not enough to actually perform a reboot.
Architecture/platform code must be provided as well, in the form of a
sys_arch_reboot() function.

Change-Id: I5b2b15855ff06453f2764f3e3b3b7d6a4a078723
Signed-off-by: Benjamin Walsh <benjamin.walsh@windriver.com>

3 files changed, 51 insertions, 0 deletions

diff --git a/misc/Kconfig b/misc/Kconfig
index 00cd1d146..8fa1a8cd1 100644
--- a/misc/Kconfig
+++ b/misc/Kconfig
@@ -260,3 +260,11 @@ config  CPU_CLOCK_FREQ_MHZ
 
 endmenu
 
+config REBOOT
+	bool "Reboot functionality"
+	default n
+	select SYSTEM_CLOCK_DISABLE
+	help
+	Enable the sys_reboot() API. Enabling this can drag in other subsystems
+	needed to perform a "safe" reboot (e.g. SYSTEM_CLOCK_DISABLE, to stop the
+	system clock before issuing a reset).
diff --git a/misc/Makefile b/misc/Makefile
index 635389621..cca7f4dee 100644
--- a/misc/Makefile
+++ b/misc/Makefile
@@ -1,4 +1,5 @@
 obj-y =
 obj-$(CONFIG_PRINTK) += printk.o
+obj-$(CONFIG_REBOOT) += reboot.o
 obj-y += generated/
 obj-y += debug/
diff --git a/misc/reboot.c b/misc/reboot.c
new file mode 100644
index 000000000..49576bbc2
--- /dev/null
+++ b/misc/reboot.c
@@ -0,0 +1,42 @@
+/*
+ * Copyright (c) 2015 Wind River Systems, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/**
+ * @file common target reboot functionality
+ *
+ * @details See misc/Kconfig and the reboot help for details.
+ */
+
+#include <nanokernel.h>
+#include <drivers/system_timer.h>
+#include <misc/printk.h>
+#include <misc/reboot.h>
+
+extern void sys_arch_reboot(int type);
+
+void sys_reboot(int type)
+{
+	(void)irq_lock();
+	sys_clock_disable();
+
+	sys_arch_reboot(type);
+
+	/* should never get here */
+	printk("Failed to reboot: spinning endlessly...\n");
+	for (;;) {
+		nano_cpu_idle();
+	}
+}