[PATCH v3 6/7] ARM: smp_twd: add clock api support

[robherring2@gmail.com (Rob Herring)]

From: Rob Herring <rob.herring@calxeda.com>

The private timer freq is currently dynamically detected
using jiffies count to determine the rate. This method adds
a delay to boot-up, so use the clock api instead to get the
clock rate.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
---
v3: Save struct clk pointer for later use (cpufreq).

 arch/arm/include/asm/smp_twd.h |    1 +
 arch/arm/kernel/smp_twd.c      |   14 ++++++++++++++
 2 files changed, 15 insertions(+), 0 deletions(-)

diff --git a/arch/arm/include/asm/smp_twd.h b/arch/arm/include/asm/smp_twd.h
index fed9981..6b0f591 100644
--- a/arch/arm/include/asm/smp_twd.h
+++ b/arch/arm/include/asm/smp_twd.h
@@ -24,5 +24,6 @@ extern void __iomem *twd_base;
 
 int twd_timer_ack(void);
 void twd_timer_setup(struct clock_event_device *);
+void twd_timer_init(void __iomem *base);
 
 #endif
diff --git a/arch/arm/kernel/smp_twd.c b/arch/arm/kernel/smp_twd.c
index 60636f4..cce1171 100644
--- a/arch/arm/kernel/smp_twd.c
+++ b/arch/arm/kernel/smp_twd.c
@@ -8,6 +8,8 @@
  * it under the terms of the GNU General Public License version 2 as
  * published by the Free Software Foundation.
  */
+#include <linux/clk.h>
+#include <linux/err.h>
 #include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/delay.h>
@@ -24,6 +26,7 @@
 /* set up by the platform code */
 void __iomem *twd_base;
 
+static struct clk *twd_clk;
 static unsigned long twd_timer_rate;
 
 static void twd_set_mode(enum clock_event_mode mode,
@@ -142,3 +145,14 @@ void __cpuinit twd_timer_setup(struct clock_event_device *clk)
 
 	clockevents_register_device(clk);
 }
+
+void __init twd_timer_init(void __iomem *base)
+{
+	twd_clk = clk_get_sys("smp_twd", NULL);
+	if (!IS_ERR(twd_clk))
+		twd_timer_rate = clk_get_rate(twd_clk);
+	else
+		twd_clk = NULL;
+
+	twd_base = base;
+}
-- 
1.7.1