[EXT] Re: [PATCH v2 2/2] imx: Support i.MX91 11x11 FRDM board

[Joseph Guo (OSS)]

On 12/3/2025 10:27 PM, Fabio Estevam wrote:
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> 
> On Tue, Dec 2, 2025 at 7:05 AM Joseph Guo <qijian.guo at nxp.com> wrote:
> 
>> +&usdhc2 {
>> +       fsl,signal-voltage-switch-extra-delay-ms = <8>;
> 
> Why does U-Boot need this property? It doesn't exist in Linux,
> 
Hi Fabio,

USDHC2 is for SD card and its initial stage is at u-boot.
The IO voltage switch from 3.3v to 1.8v need extra 8ms time on some 
platform. I also tested without this delay, SD card can work as SD3.0 on 
imx91 frdm platform.

I prefer to remain this to avoid potential risk as 91evk 93evk 93frdm 
all remain this property.

>> +};
>> +
>> +&fec {
>> +       compatible = "fsl,imx91-fec", "fsl,imx93-fec", "fsl,imx8mq-fec";
>> +       phy-reset-gpios = <&pcal6524 16 GPIO_ACTIVE_LOW>;
>> +       phy-reset-duration = <15>;
>> +       phy-reset-post-delay = <100>;
> 
> Using phy-reset-gpios is considered deprecated.
> 
> The PHY reset GPIO should be described inside the MDIO node.
> 
Ok, will change to main dts MDIO node.
>> +&ethphy1 {
>> +       reset-gpios = <&pcal6524 15 GPIO_ACTIVE_LOW>;
>> +       reset-assert-us = <15000>;
>> +       reset-deassert-us = <100000>;
> 
> Why is this inside the u-boot.dtsi instead of the main dts?
> 

Can move to main dts.
> 
>> +#define CFG_SYS_SDRAM_BASE     0x80000000
>> +#define PHYS_SDRAM             0x80000000
>> +#define PHYS_SDRAM_SIZE                0x80000000 /* 2GB DDR */
> 
> What about:
> 
> #define PHYS_SDRAM_SIZE   SIZE_2GB
make sense, will change.

Regards,
Joseph