Hi,

On Tue, Jan 10, 2017 at 01:01:20AM +0800, Chen-Yu Tsai wrote:

On Tue, Jan 10, 2017 at 12:46 AM, Maxime Ripard
[off-list ref] wrote:

quoted

All the controllers can have a maximum frequency of 200MHz.

Since older SoCs cannot go that high, we cannot change the default maximum
frequency, but fortunately for us we have a property for that in the DT.

This also has the side effect of allowing to use the MMC HS200 mode for the
boards that support it (with either 1.2v or 1.8v IOs).

Signed-off-by: Maxime Ripard <redacted>
---
 arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi | 3 +++
 1 file changed, 3 insertions(+), 0 deletions(-)

diff --git a/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi b/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi
index 8e149498e096..f46ae965cf5b 100644
--- a/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi
+++ b/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi

@@ -332,6 +332,7 @@
                        resets = <&ccu RST_BUS_MMC0>;
                        reset-names = "ahb";
                        interrupts = <GIC_SPI 60 IRQ_TYPE_LEVEL_HIGH>;
+                       max-frequency = <200000000>;

You also have to set one of MMC_CAP2_HS200* in the driver,
or mmc-hs200-1_8v or mmc-hs200-1_2v in the device tree to
actually use HS200, right?

Yes, but that requires a board with 1.8V IOs to work properly, which
not all board use, so it's probably best to enable it in the board
DTS.

Thanks!
Maxime

-- 
Maxime Ripard, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com
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