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* [PATCH] ARM: dts: at91: sama7g5ek: Align the impedance of the QSPI0's HSIO and PCB lines
@ 2022-04-06 13:05 ` Tudor Ambarus
  0 siblings, 0 replies; 14+ messages in thread
From: Tudor Ambarus @ 2022-04-06 13:05 UTC (permalink / raw)
  To: nicolas.ferre, claudiu.beznea
  Cc: alexandre.belloni, devicetree, linux-arm-kernel, linux-kernel,
	Tudor Ambarus, Mihai Sain

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@microchip.com>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
---
 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 {
-- 
2.25.1


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linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply related	[flat|nested] 14+ messages in thread

* [PATCH] ARM: dts: at91: sama7g5ek: Align the impedance of the QSPI0's HSIO and PCB lines
@ 2022-04-06 13:05 ` Tudor Ambarus
  0 siblings, 0 replies; 14+ messages in thread
From: Tudor Ambarus @ 2022-04-06 13:05 UTC (permalink / raw)
  To: nicolas.ferre, claudiu.beznea
  Cc: alexandre.belloni, devicetree, linux-arm-kernel, linux-kernel,
	Tudor Ambarus, Mihai Sain

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@microchip.com>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
---
 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 {
-- 
2.25.1


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* Re: [PATCH] ARM: dts: at91: sama7g5ek: Align the impedance of the QSPI0's HSIO and PCB lines
  2022-04-06 13:05 ` Tudor Ambarus
@ 2022-04-07  6:26   ` Claudiu.Beznea
  -1 siblings, 0 replies; 14+ messages in thread
From: Claudiu.Beznea @ 2022-04-07  6:26 UTC (permalink / raw)
  To: Tudor.Ambarus, Nicolas.Ferre
  Cc: alexandre.belloni, devicetree, linux-arm-kernel, linux-kernel,
	Mihai.Sain

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@microchip.com>
> Signed-off-by: Tudor Ambarus <tudor.ambarus@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 {


^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [PATCH] ARM: dts: at91: sama7g5ek: Align the impedance of the QSPI0's HSIO and PCB lines
@ 2022-04-07  6:26   ` Claudiu.Beznea
  0 siblings, 0 replies; 14+ messages in thread
From: Claudiu.Beznea @ 2022-04-07  6:26 UTC (permalink / raw)
  To: Tudor.Ambarus, Nicolas.Ferre
  Cc: alexandre.belloni, devicetree, linux-arm-kernel, linux-kernel,
	Mihai.Sain

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@microchip.com>
> Signed-off-by: Tudor Ambarus <tudor.ambarus@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 {

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [PATCH] ARM: dts: at91: sama7g5ek: Align the impedance of the QSPI0's HSIO and PCB lines
  2022-04-07  6:26   ` Claudiu.Beznea
@ 2022-04-07  7:51     ` Tudor.Ambarus
  -1 siblings, 0 replies; 14+ messages in thread
From: Tudor.Ambarus @ 2022-04-07  7:51 UTC (permalink / raw)
  To: Claudiu.Beznea, Nicolas.Ferre
  Cc: alexandre.belloni, devicetree, linux-arm-kernel, linux-kernel,
	Mihai.Sain

On 4/7/22 09:26, Claudiu Beznea - M18063 wrote:
> 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@microchip.com>
>> Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
> 
> Is it necessary a fixes tag here?
> 

It's not a fix per se, it's just a fine tuning that's why I chose to don't add
the fixes tag. The memory that we have populated on sama7g5ek works fine even
with high drive strength, but it's better to adjust it and use medium instead,
in case some other flashes with higher frequencies are tested. If you think a
fixes tag is needed, give me a sign and I'll resubmit.

> 
>> ---
>>  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 {
> 


^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [PATCH] ARM: dts: at91: sama7g5ek: Align the impedance of the QSPI0's HSIO and PCB lines
@ 2022-04-07  7:51     ` Tudor.Ambarus
  0 siblings, 0 replies; 14+ messages in thread
From: Tudor.Ambarus @ 2022-04-07  7:51 UTC (permalink / raw)
  To: Claudiu.Beznea, Nicolas.Ferre
  Cc: alexandre.belloni, devicetree, linux-arm-kernel, linux-kernel,
	Mihai.Sain

On 4/7/22 09:26, Claudiu Beznea - M18063 wrote:
> 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@microchip.com>
>> Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
> 
> Is it necessary a fixes tag here?
> 

It's not a fix per se, it's just a fine tuning that's why I chose to don't add
the fixes tag. The memory that we have populated on sama7g5ek works fine even
with high drive strength, but it's better to adjust it and use medium instead,
in case some other flashes with higher frequencies are tested. If you think a
fixes tag is needed, give me a sign and I'll resubmit.

> 
>> ---
>>  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 {
> 

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [PATCH] ARM: dts: at91: sama7g5ek: Align the impedance of the QSPI0's HSIO and PCB lines
  2022-04-07  7:51     ` Tudor.Ambarus
@ 2022-04-07  8:24       ` Claudiu.Beznea
  -1 siblings, 0 replies; 14+ messages in thread
From: Claudiu.Beznea @ 2022-04-07  8:24 UTC (permalink / raw)
  To: Tudor.Ambarus, Nicolas.Ferre
  Cc: alexandre.belloni, devicetree, linux-arm-kernel, linux-kernel,
	Mihai.Sain

On 07.04.2022 10:51, Tudor Ambarus - M18064 wrote:
> On 4/7/22 09:26, Claudiu Beznea - M18063 wrote:
>> 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@microchip.com>
>>> Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
>>
>> Is it necessary a fixes tag here?
>>
> 
> It's not a fix per se, it's just a fine tuning that's why I chose to don't add
> the fixes tag. The memory that we have populated on sama7g5ek works fine even
> with high drive strength, but it's better to adjust it and use medium instead,
> in case some other flashes with higher frequencies are tested. If you think a
> fixes tag is needed, give me a sign and I'll resubmit.

Its good for me as is. Just wanted to be sure it hasn't been forgotten.
Thank you!

Reviewed-by: Claudiu Beznea <claudiu.beznea@microchip.com>

> 
>>
>>> ---
>>>  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 {
>>
> 


^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [PATCH] ARM: dts: at91: sama7g5ek: Align the impedance of the QSPI0's HSIO and PCB lines
@ 2022-04-07  8:24       ` Claudiu.Beznea
  0 siblings, 0 replies; 14+ messages in thread
From: Claudiu.Beznea @ 2022-04-07  8:24 UTC (permalink / raw)
  To: Tudor.Ambarus, Nicolas.Ferre
  Cc: alexandre.belloni, devicetree, linux-arm-kernel, linux-kernel,
	Mihai.Sain

On 07.04.2022 10:51, Tudor Ambarus - M18064 wrote:
> On 4/7/22 09:26, Claudiu Beznea - M18063 wrote:
>> 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@microchip.com>
>>> Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
>>
>> Is it necessary a fixes tag here?
>>
> 
> It's not a fix per se, it's just a fine tuning that's why I chose to don't add
> the fixes tag. The memory that we have populated on sama7g5ek works fine even
> with high drive strength, but it's better to adjust it and use medium instead,
> in case some other flashes with higher frequencies are tested. If you think a
> fixes tag is needed, give me a sign and I'll resubmit.

Its good for me as is. Just wanted to be sure it hasn't been forgotten.
Thank you!

Reviewed-by: Claudiu Beznea <claudiu.beznea@microchip.com>

> 
>>
>>> ---
>>>  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 {
>>
> 

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [PATCH] ARM: dts: at91: sama7g5ek: Align the impedance of the QSPI0's HSIO and PCB lines
  2022-04-06 13:05 ` Tudor Ambarus
@ 2022-04-13 12:40   ` Nicolas Ferre
  -1 siblings, 0 replies; 14+ messages in thread
From: Nicolas Ferre @ 2022-04-13 12:40 UTC (permalink / raw)
  To: Tudor Ambarus, claudiu.beznea
  Cc: alexandre.belloni, devicetree, linux-arm-kernel, linux-kernel,
	Mihai Sain

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@microchip.com>
> Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>

Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
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

^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [PATCH] ARM: dts: at91: sama7g5ek: Align the impedance of the QSPI0's HSIO and PCB lines
@ 2022-04-13 12:40   ` Nicolas Ferre
  0 siblings, 0 replies; 14+ messages in thread
From: Nicolas Ferre @ 2022-04-13 12:40 UTC (permalink / raw)
  To: Tudor Ambarus, claudiu.beznea
  Cc: alexandre.belloni, devicetree, linux-arm-kernel, linux-kernel,
	Mihai Sain

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@microchip.com>
> Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>

Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
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

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [PATCH] ARM: dts: at91: sama7g5ek: Align the impedance of the QSPI0's HSIO and PCB lines
  2022-04-06 13:05 ` Tudor Ambarus
@ 2022-04-13 12:43   ` Nicolas Ferre
  -1 siblings, 0 replies; 14+ messages in thread
From: Nicolas Ferre @ 2022-04-13 12:43 UTC (permalink / raw)
  To: Tudor Ambarus, claudiu.beznea
  Cc: alexandre.belloni, devicetree, linux-arm-kernel, linux-kernel,
	Mihai Sain

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@microchip.com>
> Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>

Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>

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

^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [PATCH] ARM: dts: at91: sama7g5ek: Align the impedance of the QSPI0's HSIO and PCB lines
@ 2022-04-13 12:43   ` Nicolas Ferre
  0 siblings, 0 replies; 14+ messages in thread
From: Nicolas Ferre @ 2022-04-13 12:43 UTC (permalink / raw)
  To: Tudor Ambarus, claudiu.beznea
  Cc: alexandre.belloni, devicetree, linux-arm-kernel, linux-kernel,
	Mihai Sain

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@microchip.com>
> Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>

Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>

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

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linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [PATCH] ARM: dts: at91: sama7g5ek: Align the impedance of the QSPI0's HSIO and PCB lines
  2022-04-08  9:10 Tudor Ambarus
@ 2022-04-27  6:08 ` Eugen.Hristev
  0 siblings, 0 replies; 14+ messages in thread
From: Eugen.Hristev @ 2022-04-27  6:08 UTC (permalink / raw)
  To: Tudor.Ambarus; +Cc: u-boot, Mihai.Sain

On 4/8/22 12:10 PM, 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.
> This is just a fine tunning. The memory that we have populated on sama7g5ek
> works fine even with high drive strength, but it's better to adjust it and
> use medium instead, in case some other flashes with higher frequencies are
> tested.
> 
> Suggested-by: Mihai Sain <mihai.sain@microchip.com>
> Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
> ---

Applied to u-boot-at91/master, thanks !

^ permalink raw reply	[flat|nested] 14+ messages in thread

* [PATCH] ARM: dts: at91: sama7g5ek: Align the impedance of the QSPI0's HSIO and PCB lines
@ 2022-04-08  9:10 Tudor Ambarus
  2022-04-27  6:08 ` Eugen.Hristev
  0 siblings, 1 reply; 14+ messages in thread
From: Tudor Ambarus @ 2022-04-08  9:10 UTC (permalink / raw)
  To: Eugen.Hristev; +Cc: u-boot, Tudor Ambarus, Mihai Sain

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.
This is just a fine tunning. The memory that we have populated on sama7g5ek
works fine even with high drive strength, but it's better to adjust it and
use medium instead, in case some other flashes with higher frequencies are
tested.

Suggested-by: Mihai Sain <mihai.sain@microchip.com>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
---
 arch/arm/dts/at91-sama7g5ek.dts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm/dts/at91-sama7g5ek.dts b/arch/arm/dts/at91-sama7g5ek.dts
index 5313c6d160..ee46112b08 100644
--- a/arch/arm/dts/at91-sama7g5ek.dts
+++ b/arch/arm/dts/at91-sama7g5ek.dts
@@ -667,7 +667,7 @@
 			 <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 {
-- 
2.25.1


^ permalink raw reply related	[flat|nested] 14+ messages in thread

end of thread, other threads:[~2022-04-27  6:08 UTC | newest]

Thread overview: 14+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-04-06 13:05 [PATCH] ARM: dts: at91: sama7g5ek: Align the impedance of the QSPI0's HSIO and PCB lines Tudor Ambarus
2022-04-06 13:05 ` Tudor Ambarus
2022-04-07  6:26 ` Claudiu.Beznea
2022-04-07  6:26   ` Claudiu.Beznea
2022-04-07  7:51   ` Tudor.Ambarus
2022-04-07  7:51     ` Tudor.Ambarus
2022-04-07  8:24     ` Claudiu.Beznea
2022-04-07  8:24       ` Claudiu.Beznea
2022-04-13 12:40 ` Nicolas Ferre
2022-04-13 12:40   ` Nicolas Ferre
2022-04-13 12:43 ` Nicolas Ferre
2022-04-13 12:43   ` Nicolas Ferre
2022-04-08  9:10 Tudor Ambarus
2022-04-27  6:08 ` Eugen.Hristev

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