[patch 10/17] LTTng timestamp sh

Mathieu Desnoyers
2008-11-12T23:33:58Z

[-- Attachment #1: sh-trace-clock.patch --]
[-- Type: text/plain, Size: 3705 bytes --]

This patch adds the timestamping mechanism in the trace-clock.h arch header
file. The new timestamp functions use the TMU channel 1.

This code only works if the TMU channel 1 is initialized during the kernel boot.

Big fat warning(TM) from Mathieu Desnoyers :

This patch seems to assume TMU channel 1 is setup at boot. Is it always true on
all SuperH boards ? Is there some Kconfig selection that should be done here ?
Make sure this patch does not break get_cycles on SuperH before merging.

From: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
CC: Paul Mundt <lethal@linux-sh.org>
CC: linux-sh@vger.kernel.org
---
arch/sh/Kconfig | 2 +
arch/sh/include/asm/timex.h | 7 +++-
arch/sh/include/asm/trace-clock.h | 58 ++++++++++++++++++++++++++++++++++++++
3 files changed, 65 insertions(+), 2 deletions(-)

Index: linux.trees.git/arch/sh/include/asm/timex.h
===================================================================
--- linux.trees.git.orig/arch/sh/include/asm/timex.h 2008-11-07 00:34:10.000000000 -0500
+++ linux.trees.git/arch/sh/include/asm/timex.h 2008-11-12 18:01:56.000000000 -0500
@@ -6,13 +6,16 @@
#ifndef __ASM_SH_TIMEX_H
#define __ASM_SH_TIMEX_H

-#define CLOCK_TICK_RATE (CONFIG_SH_PCLK_FREQ / 4) /* Underlying HZ */
+#include <linux/io.h>
+#include <asm/cpu/timer.h>
+
+#define CLOCK_TICK_RATE (HZ * 100000UL)

typedef unsigned long long cycles_t;

static __inline__ cycles_t get_cycles (void)
{
- return 0;
+ return 0xffffffff - ctrl_inl(TMU1_TCNT);
}

#endif /* __ASM_SH_TIMEX_H */
Index: linux.trees.git/arch/sh/Kconfig
===================================================================
--- linux.trees.git.orig/arch/sh/Kconfig 2008-11-07 00:34:10.000000000 -0500
+++ linux.trees.git/arch/sh/Kconfig 2008-11-12 18:01:56.000000000 -0500
@@ -11,6 +11,8 @@ config SUPERH
select HAVE_CLK
select HAVE_IDE
select HAVE_OPROFILE
+ select HAVE_TRACE_CLOCK
+ select HAVE_TRACE_CLOCK_32_TO_64
select HAVE_GENERIC_DMA_COHERENT
select HAVE_IOREMAP_PROT if MMU
help
Index: linux.trees.git/arch/sh/include/asm/trace-clock.h
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ linux.trees.git/arch/sh/include/asm/trace-clock.h 2008-11-12 18:01:56.000000000 -0500
@@ -0,0 +1,58 @@
+/*
+ * Copyright (C) 2007,2008 Giuseppe Cavallaro <peppe.cavallaro@st.com>
+ * Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
+ *
+ * Trace clock definitions for SuperH.
+ */
+
+#ifndef _ASM_SH_TRACE_CLOCK_H
+#define _ASM_SH_TRACE_CLOCK_H
+
+#include <linux/timer.h>
+#include <asm/clock.h>
+
+extern u64 trace_clock_read_synthetic_tsc(void);
+
+static inline u32 trace_clock_get_timestamp32(void)
+{
+ return get_cycles();
+}
+
+static inline u64 trace_clock_get_timestamp64(void)
+{
+ return trace_clock_read_synthetic_tsc();
+}
+
+static inline unsigned int trace_clock_frequency(void)
+{
+ unsigned long rate;
+ struct clk *tmu1_clk;
+
+ tmu1_clk = clk_get(NULL, "tmu1_clk");
+ rate = clk_get_rate(tmu1_clk);
+
+ return (unsigned int)rate;
+}
+
+static inline u32 trace_clock_freq_scale(void)
+{
+ return 1;
+}
+
+extern void get_synthetic_tsc(void);
+extern void put_synthetic_tsc(void);
+
+static inline void get_trace_clock(void)
+{
+ get_synthetic_tsc();
+}
+
+static inline void put_trace_clock(void)
+{
+ put_synthetic_tsc();
+}
+
+static inline void set_trace_clock_is_sync(int state)
+{
+}
+#endif /* _ASM_SH_TRACE_CLOCK_H */