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

Eugeniy Paltsev Eugeniy.Paltsev at synopsys.com
Tue Sep 12 11:20:45 PDT 2017


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.

Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev at synopsys.com>
---
 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>;
 			};
 
-- 
2.9.3




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