[PATCH v2] arm64: dts: rockchip: remove mmc-hs400-enhanced-strobe from rk3399-khadas-edge

[Artem Lapkin]

Remove mmc-hs400-enhanced-strobe from the rk3399-khadas-edge dts to
improve compatibility with a wider range of eMMC chips.

Before (BJTD4R 29.1 GiB):

[    7.001493] mmc2: CQHCI version 5.10
[    7.027971] mmc2: SDHCI controller on fe330000.mmc [fe330000.mmc] using ADMA
.......
[    7.207086] mmc2: mmc_select_hs400es failed, error -110
[    7.207129] mmc2: error -110 whilst initialising MMC card
[    7.308893] mmc2: mmc_select_hs400es failed, error -110
[    7.308921] mmc2: error -110 whilst initialising MMC card
[    7.427524] mmc2: mmc_select_hs400es failed, error -110
[    7.427546] mmc2: error -110 whilst initialising MMC card
[    7.590993] mmc2: mmc_select_hs400es failed, error -110
[    7.591012] mmc2: error -110 whilst initialising MMC card

After:

[    6.960785] mmc2: CQHCI version 5.10
[    6.984672] mmc2: SDHCI controller on fe330000.mmc [fe330000.mmc] using ADMA
[    7.175021] mmc2: Command Queue Engine enabled
[    7.175053] mmc2: new HS400 MMC card at address 0001
[    7.175808] mmcblk2: mmc2:0001 BJTD4R 29.1 GiB
[    7.176033] mmcblk2boot0: mmc2:0001 BJTD4R 4.00 MiB
[    7.176245] mmcblk2boot1: mmc2:0001 BJTD4R 4.00 MiB
[    7.176495] mmcblk2rpmb: mmc2:0001 BJTD4R 4.00 MiB, chardev (242:0)

Signed-off-by: Artem Lapkin <art at khadas.com>
---
 arch/arm64/boot/dts/rockchip/rk3399-khadas-edge.dtsi | 1 -
 1 file changed, 1 deletion(-)

V2: update & tidy commit message + put testing information here
(suggested by Christian Hewitt <christianshewitt at gmail.com> )

Testing with a selection of eMMC modules shows no observable performance
difference. For example, testing with DUTA42 116 GiB & BJTD4R 29.1 GiB:

..... mmc-hs400-enhanced-strobe disabled
[    7.175053] mmc2: new HS400 MMC card at address 0001
786432000 bytes (786 MB, 750 MiB) copied, 3 s, 262 MB/s

..... mmc-hs400-enhanced-strobe enabled
[    7.135880] mmc2: Command Queue Engine enabled
[    7.135928] mmc2: new HS400 Enhanced strobe MMC card at address 0001
[    7.136992] mmcblk2: mmc2:0001 DUTA42 116 GiB
1048576000 bytes (1.0 GB, 1000 MiB) copied, 4 s, 262 MB/s

diff --git a/arch/arm64/boot/dts/rockchip/rk3399-khadas-edge.dtsi b/arch/arm64/boot/dts/rockchip/rk3399-khadas-edge.dtsi
index d5c7648c841d..f1fcc6b5b402 100644
--- a/arch/arm64/boot/dts/rockchip/rk3399-khadas-edge.dtsi
+++ b/arch/arm64/boot/dts/rockchip/rk3399-khadas-edge.dtsi
@@ -705,7 +705,6 @@ &sdmmc {
 &sdhci {
 	bus-width = <8>;
 	mmc-hs400-1_8v;
-	mmc-hs400-enhanced-strobe;
 	non-removable;
 	status = "okay";
 };
-- 
2.25.1