1 files changed, 76 insertions, 0 deletions
diff --git a/include/asm-generic/trace-clock.h b/include/asm-generic/trace-clock.h
new file mode 100644
index 00000000000..138ac9b7c54
--- /dev/null
+++ b/include/asm-generic/trace-clock.h
@@ -0,0 +1,76 @@
+#ifndef _ASM_GENERIC_TRACE_CLOCK_H
+#define _ASM_GENERIC_TRACE_CLOCK_H
+
+/*
+ * include/asm-generic/trace-clock.h
+ *
+ * Copyright (C) 2007 - Mathieu Desnoyers (mathieu.desnoyers@polymtl.ca)
+ *
+ * Generic tracing clock for architectures without TSC.
+ */
+
+#include <linux/param.h>	/* For HZ */
+#include <asm/atomic.h>
+
+#define TRACE_CLOCK_SHIFT 13
+
+/*
+ * Number of hardware clock bits. The higher order bits are expected to be 0.
+ * If the hardware clock source has more than 32 bits, the bits higher than the
+ * 32nd will be truncated by a cast to a 32 bits unsigned. Range : 1 - 32.
+ * (too few bits would be unrealistic though, since we depend on the timer to
+ * detect the overflows).
+ */
+#define TC_HW_BITS			32
+
+/* Expected maximum interrupt latency in ms : 15ms, *2 for security */
+#define TC_EXPECTED_INTERRUPT_LATENCY	30
+
+extern atomic_long_t trace_clock_var;
+
+static inline u32 trace_clock_read32(void)
+{
+	return (u32)atomic_long_add_return(1, &trace_clock_var);
+}
+
+#ifdef CONFIG_HAVE_TRACE_CLOCK_32_TO_64
+extern u64 trace_clock_read_synthetic_tsc(void);
+extern void get_synthetic_tsc(void);
+extern void put_synthetic_tsc(void);
+
+static inline u64 trace_clock_read64(void)
+{
+	return trace_clock_read_synthetic_tsc();
+}
+#else
+static inline void get_synthetic_tsc(void)
+{
+}
+
+static inline void put_synthetic_tsc(void)
+{
+}
+
+static inline u64 trace_clock_read64(void)
+{
+	return atomic_long_add_return(1, &trace_clock_var);
+}
+#endif
+
+static inline unsigned int trace_clock_frequency(void)
+{
+	return HZ << TRACE_CLOCK_SHIFT;
+}
+
+static inline u32 trace_clock_freq_scale(void)
+{
+	return 1;
+}
+
+extern void get_trace_clock(void);
+extern void put_trace_clock(void);
+
+static inline void set_trace_clock_is_sync(int state)
+{
+}
+#endif /* _ASM_GENERIC_TRACE_CLOCK_H */