[PATCH] ARM: dts: at91: sama7g5ek: Align the impedance of the QSPI0's HSIO and PCB lines

Claudiu.Beznea at microchip.com Claudiu.Beznea at microchip.com
Wed Apr 6 23:26:37 PDT 2022


Hi, Tudor,

On 06.04.2022 16:05, Tudor Ambarus wrote:
> The impedance of the QSPI PCB lines on the sama7g5ek is 50 Ohms.
> Align the output impedance of the QSPI0 HSIOs by setting a medium drive
> strength which corresponds to an impedance of 56 Ohms when VDD is in the
> 3.0V - 3.6V range. The high drive strength setting corresponds to an
> output impedance of 42 Ohms on the QSPI0 HSIOs.
> 
> Suggested-by: Mihai Sain <mihai.sain at microchip.com>
> Signed-off-by: Tudor Ambarus <tudor.ambarus at microchip.com>

Is it necessary a fixes tag here?

Thank you,
Claudiu Beznea

> ---
>  arch/arm/boot/dts/at91-sama7g5ek.dts | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/arch/arm/boot/dts/at91-sama7g5ek.dts b/arch/arm/boot/dts/at91-sama7g5ek.dts
> index 08685a10eda1..8f9643170ba3 100644
> --- a/arch/arm/boot/dts/at91-sama7g5ek.dts
> +++ b/arch/arm/boot/dts/at91-sama7g5ek.dts
> @@ -655,7 +655,7 @@ pinctrl_qspi: qspi {
>  			 <PIN_PB21__QSPI0_INT>;
>  		bias-disable;
>  		slew-rate = <0>;
> -		atmel,drive-strength = <ATMEL_PIO_DRVSTR_HI>;
> +		atmel,drive-strength = <ATMEL_PIO_DRVSTR_ME>;
>  	};
>  
>  	pinctrl_sdmmc0_default: sdmmc0_default {



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