ARM64: dts: meson: disable sd-uhs modes on the libretech-cc

Message ID 20180426105046.14817-1-jbrunet@baylibre.com
State Accepted
Commit d5b4885b1dff72ac670b518cfeaac719d768bd4d
Headers show
Series
  • ARM64: dts: meson: disable sd-uhs modes on the libretech-cc
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Commit Message

Jerome Brunet April 26, 2018, 10:50 a.m.
There is a problem with the sd-uhs mode when doing a soft reboot.
Switching back from 1.8v to 3.3v messes with the card, which no longer
respond (timeout errors). According to the specification, we should
perform a card reset (power cycling the card) but this is something we
cannot control on this design.

Then the only solution to restore the communication with the card is an
"unplug-plug" which is not acceptable

Until we find a solution, if any, disable the sd-uhs modes on this design.
For the people using uhs at the moment, there will a performance drop as
a result.

Fixes: 3cde63ebc85c ("ARM64: dts: meson-gxl: libretech-cc: enable high speed modes")
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>

---
 arch/arm64/boot/dts/amlogic/meson-gxl-s905x-libretech-cc.dts | 3 ---
 1 file changed, 3 deletions(-)

-- 
2.14.3

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Comments

Kevin Hilman April 27, 2018, 7:15 p.m. | #1
Jerome Brunet <jbrunet@baylibre.com> writes:

> There is a problem with the sd-uhs mode when doing a soft reboot.

> Switching back from 1.8v to 3.3v messes with the card, which no longer

> respond (timeout errors). According to the specification, we should

> perform a card reset (power cycling the card) but this is something we

> cannot control on this design.

>

> Then the only solution to restore the communication with the card is an

> "unplug-plug" which is not acceptable

>

> Until we find a solution, if any, disable the sd-uhs modes on this design.

> For the people using uhs at the moment, there will a performance drop as

> a result.

>

> Fixes: 3cde63ebc85c ("ARM64: dts: meson-gxl: libretech-cc: enable high speed modes")

> Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>


Applied to v4.17/fixes, and adding a Cc to stable.

Thanks,

Kevin
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Patch

diff --git a/arch/arm64/boot/dts/amlogic/meson-gxl-s905x-libretech-cc.dts b/arch/arm64/boot/dts/amlogic/meson-gxl-s905x-libretech-cc.dts
index 3e3eb31748a3..f63bceb88caa 100644
--- a/arch/arm64/boot/dts/amlogic/meson-gxl-s905x-libretech-cc.dts
+++ b/arch/arm64/boot/dts/amlogic/meson-gxl-s905x-libretech-cc.dts
@@ -234,9 +234,6 @@ 
 
 	bus-width = <4>;
 	cap-sd-highspeed;
-	sd-uhs-sdr12;
-	sd-uhs-sdr25;
-	sd-uhs-sdr50;
 	max-frequency = <100000000>;
 	disable-wp;