Re: [PATCH] ARM: dts: at91: sam9x60: fix the SOC detection

From: Durai.ManickamKR
Date: Thu Jul 13 2023 - 04:36:47 EST


On 13/07/23 01:34, Alexandre Belloni wrote:
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> On 12/07/2023 20:42:00+0100, Conor Dooley wrote:
>>> There can be only one dbgu on a SoC and it has the chipid register. It
>>> has always been wrong to have a dbgu compatible on the flexcom uart as
>>> they are not dbgu.
>> Ahh, thanks for the explanation. Sounds like stuff that might be obvious
>> to those working on arm stuff all the time, but not all of those CCed on
>> the patch ;)
> Well, this is not really arm specific, rather microchip specific ;)
>
>> The correct thing to do would seem to be updating the dt-binding to
>> something that permits what is listed below, or just removing the second
>> compatible, to leave "microchip,sam9x60-usart" in isolation, since that
>> is permitted also.
Noted, I hope updating the yaml would be proper approach.
>>> Anyway, my advice has always been that you must not do chipid detection
>>> on at91 because there is no point in doing it because you need to have
>>> a correct dts to be able to find the dbgu chipid register so you either
>>> you already know what you are running on or you are going to read bogus
>>> registers anyway.
>> I won't claim to have an opinion on any of that, but sounds like you'd
>> be better off just reading the board/SoC level compatibles to figure out
>> what you are running on...
>>
> Yeah, exactly my point!
>
>> Thanks,
>> Conor.
>>
>>>>> Fixes: 99c808335877 (ARM: dts: at91: sam9x60: Add missing flexcom definitions)
>>>>> Signed-off-by: Durai Manickam KR <durai.manickamkr@xxxxxxxxxxxxx>
>>>>> ---
>>>>> arch/arm/boot/dts/microchip/sam9x60.dtsi | 26 ++++++++++++------------
>>>>> 1 file changed, 13 insertions(+), 13 deletions(-)
>>>>>
>>>>> diff --git a/arch/arm/boot/dts/microchip/sam9x60.dtsi b/arch/arm/boot/dts/microchip/sam9x60.dtsi
>>>>> index 8b53997675e7..73d570a17269 100644
>>>>> --- a/arch/arm/boot/dts/microchip/sam9x60.dtsi
>>>>> +++ b/arch/arm/boot/dts/microchip/sam9x60.dtsi
>>>>> @@ -172,7 +172,7 @@ flx4: flexcom@f0000000 {
>>>>> status = "disabled";
>>>>>
>>>>> uart4: serial@200 {
>>>>> - compatible = "microchip,sam9x60-dbgu", "microchip,sam9x60-usart", "atmel,at91sam9260-dbgu", "atmel,at91sam9260-usart";
>>>>> + compatible = "microchip,sam9x60-usart", "atmel,at91sam9260-usart";
>>>>> reg = <0x200 0x200>;
>>>>> interrupts = <13 IRQ_TYPE_LEVEL_HIGH 7>;
>>>>> dmas = <&dma0
>>>>> @@ -240,7 +240,7 @@ flx5: flexcom@f0004000 {
>>>>> status = "disabled";
>>>>>
>>>>> uart5: serial@200 {
>>>>> - compatible = "microchip,sam9x60-dbgu", "microchip,sam9x60-usart", "atmel,at91sam9260-dbgu", "atmel,at91sam9260-usart";
>>>>> + compatible = "microchip,sam9x60-usart", "atmel,at91sam9260-usart";
>>>>> reg = <0x200 0x200>;
>>>>> atmel,usart-mode = <AT91_USART_MODE_SERIAL>;
>>>>> interrupts = <14 IRQ_TYPE_LEVEL_HIGH 7>;
>>>>> @@ -370,7 +370,7 @@ flx11: flexcom@f0020000 {
>>>>> status = "disabled";
>>>>>
>>>>> uart11: serial@200 {
>>>>> - compatible = "microchip,sam9x60-dbgu", "microchip,sam9x60-usart", "atmel,at91sam9260-dbgu", "atmel,at91sam9260-usart";
>>>>> + compatible = "microchip,sam9x60-usart", "atmel,at91sam9260-usart";
>>>>> reg = <0x200 0x200>;
>>>>> interrupts = <32 IRQ_TYPE_LEVEL_HIGH 7>;
>>>>> dmas = <&dma0
>>>>> @@ -419,7 +419,7 @@ flx12: flexcom@f0024000 {
>>>>> status = "disabled";
>>>>>
>>>>> uart12: serial@200 {
>>>>> - compatible = "microchip,sam9x60-dbgu", "microchip,sam9x60-usart", "atmel,at91sam9260-dbgu", "atmel,at91sam9260-usart";
>>>>> + compatible = "microchip,sam9x60-usart", "atmel,at91sam9260-usart";
>>>>> reg = <0x200 0x200>;
>>>>> interrupts = <33 IRQ_TYPE_LEVEL_HIGH 7>;
>>>>> dmas = <&dma0
>>>>> @@ -576,7 +576,7 @@ flx6: flexcom@f8010000 {
>>>>> status = "disabled";
>>>>>
>>>>> uart6: serial@200 {
>>>>> - compatible = "microchip,sam9x60-dbgu", "microchip,sam9x60-usart", "atmel,at91sam9260-dbgu", "atmel,at91sam9260-usart";
>>>>> + compatible = "microchip,sam9x60-usart", "atmel,at91sam9260-usart";
>>>>> reg = <0x200 0x200>;
>>>>> interrupts = <9 IRQ_TYPE_LEVEL_HIGH 7>;
>>>>> dmas = <&dma0
>>>>> @@ -625,7 +625,7 @@ flx7: flexcom@f8014000 {
>>>>> status = "disabled";
>>>>>
>>>>> uart7: serial@200 {
>>>>> - compatible = "microchip,sam9x60-dbgu", "microchip,sam9x60-usart", "atmel,at91sam9260-dbgu", "atmel,at91sam9260-usart";
>>>>> + compatible = "microchip,sam9x60-usart", "atmel,at91sam9260-usart";
>>>>> reg = <0x200 0x200>;
>>>>> interrupts = <10 IRQ_TYPE_LEVEL_HIGH 7>;
>>>>> dmas = <&dma0
>>>>> @@ -674,7 +674,7 @@ flx8: flexcom@f8018000 {
>>>>> status = "disabled";
>>>>>
>>>>> uart8: serial@200 {
>>>>> - compatible = "microchip,sam9x60-dbgu", "microchip,sam9x60-usart", "atmel,at91sam9260-dbgu", "atmel,at91sam9260-usart";
>>>>> + compatible = "microchip,sam9x60-usart", "atmel,at91sam9260-usart";
>>>>> reg = <0x200 0x200>;
>>>>> interrupts = <11 IRQ_TYPE_LEVEL_HIGH 7>;
>>>>> dmas = <&dma0
>>>>> @@ -723,7 +723,7 @@ flx0: flexcom@f801c000 {
>>>>> status = "disabled";
>>>>>
>>>>> uart0: serial@200 {
>>>>> - compatible = "microchip,sam9x60-dbgu", "microchip,sam9x60-usart", "atmel,at91sam9260-dbgu", "atmel,at91sam9260-usart";
>>>>> + compatible = "microchip,sam9x60-usart", "atmel,at91sam9260-usart";
>>>>> reg = <0x200 0x200>;
>>>>> interrupts = <5 IRQ_TYPE_LEVEL_HIGH 7>;
>>>>> dmas = <&dma0
>>>>> @@ -791,7 +791,7 @@ flx1: flexcom@f8020000 {
>>>>> status = "disabled";
>>>>>
>>>>> uart1: serial@200 {
>>>>> - compatible = "microchip,sam9x60-dbgu", "microchip,sam9x60-usart", "atmel,at91sam9260-dbgu", "atmel,at91sam9260-usart";
>>>>> + compatible = "microchip,sam9x60-usart", "atmel,at91sam9260-usart";
>>>>> reg = <0x200 0x200>;
>>>>> interrupts = <6 IRQ_TYPE_LEVEL_HIGH 7>;
>>>>> dmas = <&dma0
>>>>> @@ -859,7 +859,7 @@ flx2: flexcom@f8024000 {
>>>>> status = "disabled";
>>>>>
>>>>> uart2: serial@200 {
>>>>> - compatible = "microchip,sam9x60-dbgu", "microchip,sam9x60-usart", "atmel,at91sam9260-dbgu", "atmel,at91sam9260-usart";
>>>>> + compatible = "microchip,sam9x60-usart", "atmel,at91sam9260-usart";
>>>>> reg = <0x200 0x200>;
>>>>> interrupts = <7 IRQ_TYPE_LEVEL_HIGH 7>;
>>>>> dmas = <&dma0
>>>>> @@ -927,7 +927,7 @@ flx3: flexcom@f8028000 {
>>>>> status = "disabled";
>>>>>
>>>>> uart3: serial@200 {
>>>>> - compatible = "microchip,sam9x60-dbgu", "microchip,sam9x60-usart", "atmel,at91sam9260-dbgu", "atmel,at91sam9260-usart";
>>>>> + compatible = "microchip,sam9x60-usart", "atmel,at91sam9260-usart";
>>>>> reg = <0x200 0x200>;
>>>>> interrupts = <8 IRQ_TYPE_LEVEL_HIGH 7>;
>>>>> dmas = <&dma0
>>>>> @@ -1050,7 +1050,7 @@ flx9: flexcom@f8040000 {
>>>>> status = "disabled";
>>>>>
>>>>> uart9: serial@200 {
>>>>> - compatible = "microchip,sam9x60-dbgu", "microchip,sam9x60-usart", "atmel,at91sam9260-dbgu", "atmel,at91sam9260-usart";
>>>>> + compatible = "microchip,sam9x60-usart", "atmel,at91sam9260-usart";
>>>>> reg = <0x200 0x200>;
>>>>> interrupts = <15 IRQ_TYPE_LEVEL_HIGH 7>;
>>>>> dmas = <&dma0
>>>>> @@ -1099,7 +1099,7 @@ flx10: flexcom@f8044000 {
>>>>> status = "disabled";
>>>>>
>>>>> uart10: serial@200 {
>>>>> - compatible = "microchip,sam9x60-dbgu", "microchip,sam9x60-usart", "atmel,at91sam9260-dbgu", "atmel,at91sam9260-usart";
>>>>> + compatible = "microchip,sam9x60-usart", "atmel,at91sam9260-usart";
>>>>> reg = <0x200 0x200>;
>>>>> interrupts = <16 IRQ_TYPE_LEVEL_HIGH 7>;
>>>>> dmas = <&dma0
>>>>> --
>>>>> 2.25.1
>>>>>
>>>
>>>
>>> --
>>> Alexandre Belloni, co-owner and COO, Bootlin
>>> Embedded Linux and Kernel engineering
>>> https://bootlin.com
>
>
> --
> Alexandre Belloni, co-owner and COO, Bootlin
> Embedded Linux and Kernel engineering
> https://bootlin.com