Re: [PATCH 09/10] arm64: dts: imx8ulp-evk: add 100MHz/200MHz pinctrl setting for eMMC

On Mon, Jul 24, 2023 at 06:51:17AM +0000, Bough Chen wrote:

quoted

-----Original Message-----
From: Shawn Guo <shawnguo@kernel.org>
Sent: 2023年7月18日 11:32
To: Peng Fan (OSS) <redacted>
Cc: robh+dt@kernel.org; krzysztof.kozlowski+dt@linaro.org;
s.hauer@pengutronix.de; kernel@pengutronix.de; festevam@gmail.com;
dl-linux-imx [off-list ref]; devicetree@vger.kernel.org;
linux-arm-kernel@lists.infradead.org; linux-kernel@vger.kernel.org; Bough
Chen [off-list ref]; Sherry Sun [off-list ref]; Peng Fan
[off-list ref]
Subject: Re: [PATCH 09/10] arm64: dts: imx8ulp-evk: add 100MHz/200MHz
pinctrl setting for eMMC

On Sun, Jun 25, 2023 at 08:42:37PM +0800, Peng Fan (OSS) wrote:

quoted

From: Haibo Chen <haibo.chen@nxp.com>

Add 100MHz and 200MHz pinctrl setting for eMMC, and enable 8 bit bus
mode to config the eMMC work at HS400ES mode.

Also update to use Standard Drive Strength for USDHC pad to get a
better signal quality per Hardware team suggests.

Reviewed-by: Sherry Sun <redacted>
Signed-off-by: Haibo Chen <haibo.chen@nxp.com>
Signed-off-by: Peng Fan <peng.fan@nxp.com>
---
 arch/arm64/boot/dts/freescale/imx8ulp-evk.dts | 26
++++++++++---------
 1 file changed, 14 insertions(+), 12 deletions(-)

diff --git a/arch/arm64/boot/dts/freescale/imx8ulp-evk.dts

b/arch/arm64/boot/dts/freescale/imx8ulp-evk.dts
index e459dc35e469..ab7af705bbca 100644

--- a/arch/arm64/boot/dts/freescale/imx8ulp-evk.dts
+++ b/arch/arm64/boot/dts/freescale/imx8ulp-evk.dts

@@ -121,9 +121,11 @@ &lpuart5 {
 };

 &usdhc0 {
-	pinctrl-names = "default", "sleep";
+	pinctrl-names = "default", "state_100mhz", "state_200mhz", "sleep";
 	pinctrl-0 = <&pinctrl_usdhc0>;
 	pinctrl-1 = <&pinctrl_usdhc0>;
+	pinctrl-2 = <&pinctrl_usdhc0>;
+	pinctrl-3 = <&pinctrl_usdhc0>;

All three speed modes use the same pinctrl?

Yes, the IOMUX on imx8ulp do not support config different drive strength. So here use the same pinctrl.

Mention that in the commit log or with a comment would be helpful.

Shawn