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

From: Bough Chen
Date: Mon Jul 24 2023 - 02:51:33 EST


> -----Original Message-----
> From: Shawn Guo <shawnguo@xxxxxxxxxx>
> Sent: 2023年7月18日 11:32
> To: Peng Fan (OSS) <peng.fan@xxxxxxxxxxx>
> Cc: robh+dt@xxxxxxxxxx; krzysztof.kozlowski+dt@xxxxxxxxxx;
> s.hauer@xxxxxxxxxxxxxx; kernel@xxxxxxxxxxxxxx; festevam@xxxxxxxxx;
> dl-linux-imx <linux-imx@xxxxxxx>; devicetree@xxxxxxxxxxxxxxx;
> linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; Bough
> Chen <haibo.chen@xxxxxxx>; Sherry Sun <sherry.sun@xxxxxxx>; Peng Fan
> <peng.fan@xxxxxxx>
> 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:
> > From: Haibo Chen <haibo.chen@xxxxxxx>
> >
> > 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 <sherry.sun@xxxxxxx>
> > Signed-off-by: Haibo Chen <haibo.chen@xxxxxxx>
> > Signed-off-by: Peng Fan <peng.fan@xxxxxxx>
> > ---
> > 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.

Best Regards
Haibo Chen
>
> Shawn
>
> > non-removable;
> > bus-width = <8>;
> > status = "okay";
> > @@ -202,17 +204,17 @@ MX8ULP_PAD_PTF15__LPUART5_RX 0x3
> >
> > pinctrl_usdhc0: usdhc0grp {
> > fsl,pins = <
> > - MX8ULP_PAD_PTD1__SDHC0_CMD 0x43
> > - MX8ULP_PAD_PTD2__SDHC0_CLK 0x10042
> > - MX8ULP_PAD_PTD10__SDHC0_D0 0x43
> > - MX8ULP_PAD_PTD9__SDHC0_D1 0x43
> > - MX8ULP_PAD_PTD8__SDHC0_D2 0x43
> > - MX8ULP_PAD_PTD7__SDHC0_D3 0x43
> > - MX8ULP_PAD_PTD6__SDHC0_D4 0x43
> > - MX8ULP_PAD_PTD5__SDHC0_D5 0x43
> > - MX8ULP_PAD_PTD4__SDHC0_D6 0x43
> > - MX8ULP_PAD_PTD3__SDHC0_D7 0x43
> > - MX8ULP_PAD_PTD11__SDHC0_DQS 0x10042
> > + MX8ULP_PAD_PTD1__SDHC0_CMD 0x3
> > + MX8ULP_PAD_PTD2__SDHC0_CLK 0x10002
> > + MX8ULP_PAD_PTD10__SDHC0_D0 0x3
> > + MX8ULP_PAD_PTD9__SDHC0_D1 0x3
> > + MX8ULP_PAD_PTD8__SDHC0_D2 0x3
> > + MX8ULP_PAD_PTD7__SDHC0_D3 0x3
> > + MX8ULP_PAD_PTD6__SDHC0_D4 0x3
> > + MX8ULP_PAD_PTD5__SDHC0_D5 0x3
> > + MX8ULP_PAD_PTD4__SDHC0_D6 0x3
> > + MX8ULP_PAD_PTD3__SDHC0_D7 0x3
> > + MX8ULP_PAD_PTD11__SDHC0_DQS 0x10002
> > >;
> > };
> > };
> > --
> > 2.37.1
> >