Re: [PATCH] ARC: [plat-axs10x]: DTS: fix sdio ciu frequency

From: Vineet Gupta
Date: Tue Sep 12 2017 - 14:50:06 EST


On 09/12/2017 11:20 AM, Eugeniy Paltsev wrote:
DW sdio controller has external ciu clock divider controlled
via register in SDIO IP. It divides sdio_ref_clk
(which comes from CGU) by 16 for default. So default mmcclk
clock (which comes to sdk_in) is 25000000 Hz.

So fix wrong current value (50000000 Hz) to actual 25000000 Hz.

Is this a preventive fix or there are known issues with what we have today.
Is this triggered after addition of AXS clk driver ?


Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@xxxxxxxxxxxx>
---
arch/arc/boot/dts/axs10x_mb.dtsi | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/arch/arc/boot/dts/axs10x_mb.dtsi b/arch/arc/boot/dts/axs10x_mb.dtsi
index 0ff7e07..7bdf581 100644
--- a/arch/arc/boot/dts/axs10x_mb.dtsi
+++ b/arch/arc/boot/dts/axs10x_mb.dtsi
@@ -44,7 +44,14 @@
mmcclk: mmcclk {
compatible = "fixed-clock";
- clock-frequency = <50000000>;
+ /*
+ * DW sdio controller has external ciu clock divider
+ * controlled via register in SDIO IP. It divides
+ * sdio_ref_clk (which comes from CGU) by 16 for
+ * default. So default mmcclk clock (which comes
+ * to sdk_in) is 25000000 Hz.
+ */
+ clock-frequency = <25000000>;
#clock-cells = <0>;
};