Re: [PATCH v4 2/3] board: phytec: imx93: Add eeprom-based hardware introspection

[Christoph Stoidner <C.Stoidner@phytec.de>]

Hi Stefan,

On Mo, 2024-11-25 at 10:39 +0100, Stefan Wahren wrote:
> Hi Christoph,
> 
> Am 25.11.24 um 09:28 schrieb Christoph Stoidner:
> > Hi Stefan,
> > 
> > On Do, 2024-11-21 at 11:12 +0100, Stefan Wahren wrote:
> > > Hi Christoph,
> > > 
> > > Am 20.11.24 um 17:31 schrieb Christoph Stoidner:
> > > 
> > [...]
> > 
> > > > diff --git a/arch/arm/dts/imx93-phyboard-segin-u-boot.dtsi
> > > > b/arch/arm/dts/imx93-phyboard-segin-u-boot.dtsi
> > > > index 6897c91f4d..702d86f4e0 100644
> > > > --- a/arch/arm/dts/imx93-phyboard-segin-u-boot.dtsi
> > > > +++ b/arch/arm/dts/imx93-phyboard-segin-u-boot.dtsi
> > > > @@ -139,6 +139,13 @@
> > > >    &usdhc1 {
> > > >          bootph-pre-ram;
> > > >          bootph-some-ram;
> > > > +       /*
> > > > +        * Remove pinctrl assignments once they are added to
> > > > imx93-
> > > > phycore-som.dtsi
> > > > +        */
> > > > +       pinctrl-names = "default", "state_100mhz",
> > > > "state_200mhz";
> > > > +       pinctrl-0 = <&pinctrl_usdhc1>;
> > > > +       pinctrl-1 = <&pinctrl_usdhc1_100mhz>;
> > > > +       pinctrl-2 = <&pinctrl_usdhc1_200mhz>;
> > > >    };
> > > > 
> > > >    &usdhc2 {
> > > > @@ -215,6 +222,48 @@
> > > >                          MX93_PAD_ENET2_RD3__GPIO4_IO27
> > > >       0x31e
> > > >                  >;
> > > >          };
> > > > +
> > > > +       /*
> > > > +        * Remove pinctrl_usdhc1_100mhz and
> > > > pinctrl_usdhc1_200mhz
> > > > once they
> > > > +        * are added to imx93-phycore-som.dtsi
> > > > +        */
> > > > +       /* need to config the SION for data and cmd pad, refer
> > > > to
> > > > ERR052021 */
> > > > +       pinctrl_usdhc1_100mhz: usdhc1-100mhzgrp {
> > > > +               bootph-pre-ram;
> > > > +               bootph-some-ram;
> > > > +               fsl,pins = <
> > > > +                       MX93_PAD_SD1_CLK__USDHC1_CLK           
> > > >  0x1
> > > > 7be
> > > > +                       MX93_PAD_SD1_CMD__USDHC1_CMD           
> > > >  0x4
> > > > 000139e
> > > > +                       MX93_PAD_SD1_DATA0__USDHC1_DATA0       
> > > >  0x4
> > > > 000138e
> > > > +                       MX93_PAD_SD1_DATA1__USDHC1_DATA1       
> > > >  0x4
> > > > 000139e
> > > > +                       MX93_PAD_SD1_DATA2__USDHC1_DATA2       
> > > >  0x4
> > > > 00013be
> > > Could you please explain why the pin configuration for 100 MHz of
> > > DATA0
> > > & DATA2 is different from the other data pins?
> > The difference in the values is due to different drive-strength
> > settings per pin. The values are the result of measurements we
> > did for the eMMC interface. There, we adjusted each pin's
> > drive-strength to get it's best signal quality.
> Thanks for the explanation. So you measured also the 200 MHz case? 
> Because there are no differences between the data pins.

Yes, we measured also for 200 MHz. There the same value was perfect
for all pins.

> 
> Regards
> > 
> > Regards,
> > Christoph
> > 
> > > > +                       MX93_PAD_SD1_DATA3__USDHC1_DATA3       
> > > >  0x4
> > > > 000139e
> > > > +                       MX93_PAD_SD1_DATA4__USDHC1_DATA4       
> > > >  0x4
> > > > 000139e
> > > > +                       MX93_PAD_SD1_DATA5__USDHC1_DATA5       
> > > >  0x4
> > > > 000139e
> > > > +                       MX93_PAD_SD1_DATA6__USDHC1_DATA6       
> > > >  0x4
> > > > 000139e
> > > > +                       MX93_PAD_SD1_DATA7__USDHC1_DATA7       
> > > >  0x4
> > > > 000139e
> > > > +                       MX93_PAD_SD1_STROBE__USDHC1_STROBE     
> > > >  0x1
> > > > 79e
> > > > +               >;
> > > > +       };
> > > > +
> > > > +       /* need to config the SION for data and cmd pad, refer
> > > > to
> > > > ERR052021 */
> > > > +       pinctrl_usdhc1_200mhz: usdhc1-200mhzgrp {
> > > > +               bootph-pre-ram;
> > > > +               bootph-some-ram;
> > > > +               fsl,pins = <
> > > > +                       MX93_PAD_SD1_CLK__USDHC1_CLK           
> > > >  0x1
> > > > 7be
> > > > +                       MX93_PAD_SD1_CMD__USDHC1_CMD           
> > > >  0x4
> > > > 000139e
> > > > +                       MX93_PAD_SD1_DATA0__USDHC1_DATA0       
> > > >  0x4
> > > > 000139e
> > > > +                       MX93_PAD_SD1_DATA1__USDHC1_DATA1       
> > > >  0x4
> > > > 00013be
> > > > +                       MX93_PAD_SD1_DATA2__USDHC1_DATA2       
> > > >  0x4
> > > > 00013be
> > > > +                       MX93_PAD_SD1_DATA3__USDHC1_DATA3       
> > > >  0x4
> > > > 00013be
> > > > +                       MX93_PAD_SD1_DATA4__USDHC1_DATA4       
> > > >  0x4
> > > > 00013be
> > > > +                       MX93_PAD_SD1_DATA5__USDHC1_DATA5       
> > > >  0x4
> > > > 00013be
> > > > +                       MX93_PAD_SD1_DATA6__USDHC1_DATA6       
> > > >  0x4
> > > > 00013be
> > > > +                       MX93_PAD_SD1_DATA7__USDHC1_DATA7       
> > > >  0x4
> > > > 00013be
> > > > +                       MX93_PAD_SD1_STROBE__USDHC1_STROBE     
> > > >  0x1
> > > > 79e
> > > > +               >;
> > > > +       };
> > > >    };
> > > > 
>