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

From: Nicolas Ferre
Date: Wed Apr 13 2022 - 08:41:10 EST


On 06/04/2022 at 15:05, 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@xxxxxxxxxxxxx>
Signed-off-by: Tudor Ambarus <tudor.ambarus@xxxxxxxxxxxxx>

Acked-by: Nicolas Ferre <nicolas.ferre@xxxxxxxxxxxxx>
And queued in "fixes" branch for 5.18.

Thanks, best regards,
Nicolas

---
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 {


--
Nicolas Ferre