arm64: dts: s32g2: Disable support for SD/eMMC UHS mode

Disable SD/eMMC UHS modes for NXP boards which do not set VCCQ voltage
supply to 1.8V by default, such as S32G274A-EVB and S32G274A-RDB2.

Signed-off-by: Ciprian Marian Costea <ciprianmarian.costea@oss.nxp.com>
Reviewed-by: Matthias Brugger <mbrugger@suse.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

diff --git a/arch/arm64/boot/dts/freescale/s32g274a-evb.dts b/arch/arm64/boot/dts/freescale/s32g274a-evb.dts
index 7ab917f547ef4ccb05c352812ce10e1454bce0bb..b9a119eea2b746009f0c825486c4f4b0a6e4001c 100644 (file)
--- a/arch/arm64/boot/dts/freescale/s32g274a-evb.dts
+++ b/arch/arm64/boot/dts/freescale/s32g274a-evb.dts
@@ -39,5 +39,6 @@
        pinctrl-1 = <&pinctrl_usdhc0_100mhz>;
        pinctrl-2 = <&pinctrl_usdhc0_200mhz>;
        disable-wp;
+       no-1-8-v;
        status = "okay";
 };

diff --git a/arch/arm64/boot/dts/freescale/s32g274a-rdb2.dts b/arch/arm64/boot/dts/freescale/s32g274a-rdb2.dts
index 8739f63771bc00d7bc8926410f01f029b42cdb64..aaa61a8ad0dac3105f4619fb582f475a45936c6c 100644 (file)
--- a/arch/arm64/boot/dts/freescale/s32g274a-rdb2.dts
+++ b/arch/arm64/boot/dts/freescale/s32g274a-rdb2.dts
@@ -45,5 +45,14 @@
        pinctrl-1 = <&pinctrl_usdhc0_100mhz>;
        pinctrl-2 = <&pinctrl_usdhc0_200mhz>;
        disable-wp;
+       /* Remove no-1-8-v to enable higher speed modes for SD card.
+        * However, this is not enough to enable HS400 or HS200 modes for eMMC.
+        * In this case, the position of the resistor R797 must be changed
+        * from A to B before removing the property.
+        * If the property is removed without changing the resistor position,
+        * HS*00 may be enabled, but the interface might be unstable because of
+        * the wrong VCCQ voltage applied to the eMMC.
+        */
+       no-1-8-v;
        status = "okay";
 };