[PATCH] clk: nomadik: set all timers to use 2.4 MHz TIMCLK

Linus Walleij linus.walleij at linaro.org
Fri Sep 13 15:45:51 EDT 2013


This fixes a regression for the Nomadik on the main system
timers.

The Nomadik seemed a bit slow and its heartbeat wasn't looking
healthy. And it was not strange, because it has been connected
to the 32768 Hz clock at boot, while being told by the clock driver
that it was 2.4MHz. Actually connect the TIMCLK to 2.4MHz by
default as this is what we want for nice scheduling, clocksource
and clock event.

Cc: stable at vger.kernel.org
Signed-off-by: Linus Walleij <linus.walleij at linaro.org>
---
 drivers/clk/clk-nomadik.c | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/drivers/clk/clk-nomadik.c b/drivers/clk/clk-nomadik.c
index 51410c2..4d978a3 100644
--- a/drivers/clk/clk-nomadik.c
+++ b/drivers/clk/clk-nomadik.c
@@ -27,6 +27,14 @@
  */
 
 #define SRC_CR			0x00U
+#define SRC_CR_T0_ENSEL		BIT(15)
+#define SRC_CR_T1_ENSEL		BIT(17)
+#define SRC_CR_T2_ENSEL		BIT(19)
+#define SRC_CR_T3_ENSEL		BIT(21)
+#define SRC_CR_T4_ENSEL		BIT(23)
+#define SRC_CR_T5_ENSEL		BIT(25)
+#define SRC_CR_T6_ENSEL		BIT(27)
+#define SRC_CR_T7_ENSEL		BIT(29)
 #define SRC_XTALCR		0x0CU
 #define SRC_XTALCR_XTALTIMEN	BIT(20)
 #define SRC_XTALCR_SXTALDIS	BIT(19)
@@ -543,6 +551,19 @@ void __init nomadik_clk_init(void)
 		       __func__, np->name);
 		return;
 	}
+
+	/* Set all timers to use the 2.4 MHz TIMCLK */
+	val = readl(src_base + SRC_CR);
+	val |= SRC_CR_T0_ENSEL;
+	val |= SRC_CR_T1_ENSEL;
+	val |= SRC_CR_T2_ENSEL;
+	val |= SRC_CR_T3_ENSEL;
+	val |= SRC_CR_T4_ENSEL;
+	val |= SRC_CR_T5_ENSEL;
+	val |= SRC_CR_T6_ENSEL;
+	val |= SRC_CR_T7_ENSEL;
+	writel(val, src_base + SRC_CR);
+
 	val = readl(src_base + SRC_XTALCR);
 	pr_info("SXTALO is %s\n",
 		(val & SRC_XTALCR_SXTALDIS) ? "disabled" : "enabled");
-- 
1.8.1.4




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