From 976e78a5226598cb582fe9ef98a72861adbc0e9c Mon Sep 17 00:00:00 2001 From: Eugeniy Paltsev Date: Tue, 12 Sep 2017 21:20:45 +0300 Subject: ARC: [plat-axs10x] sdio: Temporary fix of sdio ciu frequency 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. Note this is a preventive fix, in line with similar change for HSDK where this was actually needed. see: http://lists.infradead.org/pipermail/linux-snps-arc/2017-September/002924.html Signed-off-by: Eugeniy Paltsev Signed-off-by: Vineet Gupta --- arch/arc/boot/dts/axs10x_mb.dtsi | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) (limited to 'arch/arc/boot') diff --git a/arch/arc/boot/dts/axs10x_mb.dtsi b/arch/arc/boot/dts/axs10x_mb.dtsi index 2367a67c5f10..e114000a84f5 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>; }; -- cgit v1.2.3-59-g8ed1b