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Diffstat (limited to 'arch/arm/kernel/smp_twd.c')
-rw-r--r--arch/arm/kernel/smp_twd.c48
1 files changed, 46 insertions, 2 deletions
diff --git a/arch/arm/kernel/smp_twd.c b/arch/arm/kernel/smp_twd.c
index fef42b2..e1f9069 100644
--- a/arch/arm/kernel/smp_twd.c
+++ b/arch/arm/kernel/smp_twd.c
@@ -11,7 +11,6 @@
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/clk.h>
-#include <linux/cpufreq.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/err.h>
@@ -96,7 +95,52 @@ static void twd_timer_stop(struct clock_event_device *clk)
disable_percpu_irq(clk->irq);
}
-#ifdef CONFIG_CPU_FREQ
+#ifdef CONFIG_COMMON_CLK
+
+/*
+ * Updates clockevent frequency when the cpu frequency changes.
+ * Called on the cpu that is changing frequency with interrupts disabled.
+ */
+static void twd_update_frequency(void *new_rate)
+{
+ twd_timer_rate = *((unsigned long *) new_rate);
+
+ clockevents_update_freq(*__this_cpu_ptr(twd_evt), twd_timer_rate);
+}
+
+static int twd_rate_change(struct notifier_block *nb,
+ unsigned long flags, void *data)
+{
+ struct clk_notifier_data *cnd = data;
+
+ /*
+ * The twd clock events must be reprogrammed to account for the new
+ * frequency. The timer is local to a cpu, so cross-call to the
+ * changing cpu.
+ */
+ if (flags == POST_RATE_CHANGE)
+ smp_call_function(twd_update_frequency,
+ (void *)&cnd->new_rate, 1);
+
+ return NOTIFY_OK;
+}
+
+static struct notifier_block twd_clk_nb = {
+ .notifier_call = twd_rate_change,
+};
+
+static int twd_clk_init(void)
+{
+ if (twd_evt && *__this_cpu_ptr(twd_evt) && !IS_ERR(twd_clk))
+ return clk_notifier_register(twd_clk, &twd_clk_nb);
+
+ return 0;
+}
+core_initcall(twd_clk_init);
+
+#elif defined (CONFIG_CPU_FREQ)
+
+#include <linux/cpufreq.h>
/*
* Updates clockevent frequency when the cpu frequency changes.