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-rw-r--r--include/asm-sh/watchdog.h111
1 files changed, 111 insertions, 0 deletions
diff --git a/include/asm-sh/watchdog.h b/include/asm-sh/watchdog.h
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+++ b/include/asm-sh/watchdog.h
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+/*
+ * include/asm-sh/watchdog.h
+ *
+ * Copyright (C) 2002, 2003 Paul Mundt
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ */
+#ifndef __ASM_SH_WATCHDOG_H
+#define __ASM_SH_WATCHDOG_H
+#ifdef __KERNEL__
+
+#include <linux/types.h>
+#include <linux/config.h>
+#include <asm/cpu/watchdog.h>
+#include <asm/io.h>
+
+/*
+ * See asm/cpu-sh2/watchdog.h for explanation of this stupidity..
+ */
+#ifndef WTCNT_R
+# define WTCNT_R WTCNT
+#endif
+
+#ifndef WTCSR_R
+# define WTCSR_R WTCSR
+#endif
+
+#define WTCNT_HIGH 0x5a
+#define WTCSR_HIGH 0xa5
+
+#define WTCSR_CKS2 0x04
+#define WTCSR_CKS1 0x02
+#define WTCSR_CKS0 0x01
+
+/*
+ * CKS0-2 supports a number of clock division ratios. At the time the watchdog
+ * is enabled, it defaults to a 41 usec overflow period .. we overload this to
+ * something a little more reasonable, and really can't deal with anything
+ * lower than WTCSR_CKS_1024, else we drop back into the usec range.
+ *
+ * Clock Division Ratio Overflow Period
+ * --------------------------------------------
+ * 1/32 (initial value) 41 usecs
+ * 1/64 82 usecs
+ * 1/128 164 usecs
+ * 1/256 328 usecs
+ * 1/512 656 usecs
+ * 1/1024 1.31 msecs
+ * 1/2048 2.62 msecs
+ * 1/4096 5.25 msecs
+ */
+#define WTCSR_CKS_32 0x00
+#define WTCSR_CKS_64 0x01
+#define WTCSR_CKS_128 0x02
+#define WTCSR_CKS_256 0x03
+#define WTCSR_CKS_512 0x04
+#define WTCSR_CKS_1024 0x05
+#define WTCSR_CKS_2048 0x06
+#define WTCSR_CKS_4096 0x07
+
+/**
+ * sh_wdt_read_cnt - Read from Counter
+ *
+ * Reads back the WTCNT value.
+ */
+static inline __u8 sh_wdt_read_cnt(void)
+{
+ return ctrl_inb(WTCNT_R);
+}
+
+/**
+ * sh_wdt_write_cnt - Write to Counter
+ *
+ * @val: Value to write
+ *
+ * Writes the given value @val to the lower byte of the timer counter.
+ * The upper byte is set manually on each write.
+ */
+static inline void sh_wdt_write_cnt(__u8 val)
+{
+ ctrl_outw((WTCNT_HIGH << 8) | (__u16)val, WTCNT);
+}
+
+/**
+ * sh_wdt_read_csr - Read from Control/Status Register
+ *
+ * Reads back the WTCSR value.
+ */
+static inline __u8 sh_wdt_read_csr(void)
+{
+ return ctrl_inb(WTCSR_R);
+}
+
+/**
+ * sh_wdt_write_csr - Write to Control/Status Register
+ *
+ * @val: Value to write
+ *
+ * Writes the given value @val to the lower byte of the control/status
+ * register. The upper byte is set manually on each write.
+ */
+static inline void sh_wdt_write_csr(__u8 val)
+{
+ ctrl_outw((WTCSR_HIGH << 8) | (__u16)val, WTCSR);
+}
+
+#endif /* __KERNEL__ */
+#endif /* __ASM_SH_WATCHDOG_H */