ARM: use device tree to get smp_twd clock
Move clk setup to twd_local_timer_common_register and rely on
twd_timer_rate being 0 to force calibration if there is no clock.
Remove common_setup_called as it is no longer needed.
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: Mark Langsdorf <mark.langsdorf@calxeda.com>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/arch/arm/kernel/smp_twd.c b/arch/arm/kernel/smp_twd.c
index 49f335d..ae0c7bb 100644
--- a/arch/arm/kernel/smp_twd.c
+++ b/arch/arm/kernel/smp_twd.c
@@ -31,7 +31,6 @@
static struct clk *twd_clk;
static unsigned long twd_timer_rate;
-static bool common_setup_called;
static DEFINE_PER_CPU(bool, percpu_setup_called);
static struct clock_event_device __percpu **twd_evt;
@@ -239,25 +238,28 @@
return IRQ_NONE;
}
-static struct clk *twd_get_clock(void)
+static void twd_get_clock(struct device_node *np)
{
- struct clk *clk;
int err;
- clk = clk_get_sys("smp_twd", NULL);
- if (IS_ERR(clk)) {
- pr_err("smp_twd: clock not found: %d\n", (int)PTR_ERR(clk));
- return clk;
+ if (np)
+ twd_clk = of_clk_get(np, 0);
+ else
+ twd_clk = clk_get_sys("smp_twd", NULL);
+
+ if (IS_ERR(twd_clk)) {
+ pr_err("smp_twd: clock not found %d\n", (int) PTR_ERR(twd_clk));
+ return;
}
- err = clk_prepare_enable(clk);
+ err = clk_prepare_enable(twd_clk);
if (err) {
pr_err("smp_twd: clock failed to prepare+enable: %d\n", err);
- clk_put(clk);
- return ERR_PTR(err);
+ clk_put(twd_clk);
+ return;
}
- return clk;
+ twd_timer_rate = clk_get_rate(twd_clk);
}
/*
@@ -280,26 +282,7 @@
}
per_cpu(percpu_setup_called, cpu) = true;
- /*
- * This stuff only need to be done once for the entire TWD cluster
- * during the runtime of the system.
- */
- if (!common_setup_called) {
- twd_clk = twd_get_clock();
-
- /*
- * We use IS_ERR_OR_NULL() here, because if the clock stubs
- * are active we will get a valid clk reference which is
- * however NULL and will return the rate 0. In that case we
- * need to calibrate the rate instead.
- */
- if (!IS_ERR_OR_NULL(twd_clk))
- twd_timer_rate = clk_get_rate(twd_clk);
- else
- twd_calibrate_rate();
-
- common_setup_called = true;
- }
+ twd_calibrate_rate();
/*
* The following is done once per CPU the first time .setup() is
@@ -330,7 +313,7 @@
.stop = twd_timer_stop,
};
-static int __init twd_local_timer_common_register(void)
+static int __init twd_local_timer_common_register(struct device_node *np)
{
int err;
@@ -350,6 +333,8 @@
if (err)
goto out_irq;
+ twd_get_clock(np);
+
return 0;
out_irq:
@@ -373,7 +358,7 @@
if (!twd_base)
return -ENOMEM;
- return twd_local_timer_common_register();
+ return twd_local_timer_common_register(NULL);
}
#ifdef CONFIG_OF
@@ -405,7 +390,7 @@
goto out;
}
- err = twd_local_timer_common_register();
+ err = twd_local_timer_common_register(np);
out:
WARN(err, "twd_local_timer_of_register failed (%d)\n", err);
