[PATCH v2 2/2] timer: sti: use clk API to get timer clock rate

[Nicolas Heemeryck]

Retrieve clock rate through device tree. This mimics the behavior of
arm_global_timer in Linux.

Signed-off-by: Nicolas Heemeryck <nicolas.heemeryck at gmail.com>
Cc: Patrice Chotard <patrice.chotard at st.com>

---

Changes for v2:

- Fall back on CONFIG_SYS_HZ_CLOCK if clk_get_by_index returns an
error or no clock driver is provided.
---
 drivers/timer/sti-timer.c | 17 +++++++++++++++--
 1 file changed, 15 insertions(+), 2 deletions(-)

diff --git a/drivers/timer/sti-timer.c b/drivers/timer/sti-timer.c
index eac22ae39b..ff42056abd 100644
--- a/drivers/timer/sti-timer.c
+++ b/drivers/timer/sti-timer.c
@@ -6,7 +6,9 @@
 
 #include <common.h>
 #include <dm.h>
+#include <clk.h>
 #include <timer.h>
+#include <linux/err.h>
 
 #include <asm/io.h>
 #include <asm/arch-armv7/globaltimer.h>
@@ -41,14 +43,25 @@ static int sti_timer_probe(struct udevice *dev)
 {
 	struct timer_dev_priv *uc_priv = dev_get_uclass_priv(dev);
 	struct sti_timer_priv *priv = dev_get_priv(dev);
-
-	uc_priv->clock_rate = CONFIG_SYS_HZ_CLOCK;
+	struct clk clk;
+	int err;
+	ulong ret;
 
 	/* get arm global timer base address */
 	priv->global_timer = (struct globaltimer *)dev_read_addr_ptr(dev);
 	if (!priv->global_timer)
 		return -ENOENT;
 
+	err = clk_get_by_index(dev, 0, &clk);
+	if (!err) {
+		ret = clk_get_rate(&clk);
+		if (IS_ERR_VALUE(ret))
+			return ret;
+		uc_priv->clock_rate = ret;
+	} else {
+		uc_priv->clock_rate = CONFIG_SYS_HZ_CLOCK;
+	}
+
 	/* init timer */
 	writel(0x01, &priv->global_timer->ctl);
 
-- 
2.20.1