Add header file defining a simple, yet expressive watchdog interface

which can be implemented on all the watchdog hardware I know.

1 files changed, 76 insertions, 0 deletions

diff --git a/sys/sys/watchdog.h b/sys/sys/watchdog.h
new file mode 100644
index 0000000..cd2690b
--- /dev/null
+++ b/sys/sys/watchdog.h
@@ -0,0 +1,76 @@
+/*-
+ * Copyright (c) 2003 Poul-Henning Kamp
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+#ifndef _SYS_WATCHDOG_H
+#define	_SYS__WATCHDOG_H
+
+#include <sys/ioccom.h>
+
+#define WDIOCPATPAT	_IOW('W', 42, u_int)
+
+#define WD_ACTIVE	0x8000000
+	/* 
+	 * Watchdog reset, timeout set to value in WD_INTERVAL field.
+	 * The kernel will arm the watchdog and unless the userland
+	 * program calls WDIOCPATPAT again before the timer expires
+	 * the system will reinitialize.
+	 */
+
+#define WD_PASSIVE	0x0400000
+	/*
+	 * Set the watchdog in passive mode.
+	 * The kernel will chose an appropriate timeout duration and
+	 * periodically reset the timer provided everything looks all
+	 * right to the kernel.
+ 	 */
+
+#define WD_INTERVAL	0x00000ff
+	/*
+	 * Mask for duration bits.
+	 * The watchdog will have a nominal patience of 2^N * nanoseconds.
+	 * Example:  N == 30 gives a patience of 2^30 nanoseconds ~= 1 second.
+	 * NB: Expect variance in the +/- 10-20% range.
+	 */
+
+#ifdef _KERNEL
+#define __WD_LEGAL	(WD_ACTIVE | WD_PASSIVE | WD_INTERVAL)
+#endif
+
+/* Handy macros for humans not used to power of two nanoseconds */
+#define WD_TO_NEVER	0
+#define WD_TO_1MS	20
+#define WD_TO_125MS	27
+#define WD_TO_250MS	28
+#define WD_TO_500MS	29
+#define WD_TO_1SEC	30
+#define WD_TO_2SEC	31
+#define WD_TO_4SEC	32
+#define WD_TO_8SEC	33
+#define WD_TO_16SEC	34
+#define WD_TO_32SEC	35
+
+#endif /* _SYS_WATCHDOG_H */