Re: [PATCH v1 3/6] ARM: dts: lan966x: add all flexcom usart nodes
From: Claudiu.Beznea
Date: Mon Mar 07 2022 - 06:53:28 EST
On 04.03.2022 13:01, Michael Walle wrote:
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>
> Hi,
>
> thanks for the quick review.
>
> Am 2022-03-04 09:30, schrieb Claudiu.Beznea@xxxxxxxxxxxxx:
>> On 03.03.2022 18:03, Michael Walle wrote:
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>>> the content is safe
>>>
>>> Add all the usart nodes for the flexcom block. There was already
>>> an usart node for the flexcom3 block. But it missed the DMA
>>> channels.
>>
>> And it would be good to go though a different patch.
>
> sure
>
>>> Although the DMA channels are specified, DMA is not
>>> enabled by default because break detection doesn't work with DMA.
>>>
>>> Keep the nodes disabled by default.
>>>
>>> Signed-off-by: Michael Walle <michael@xxxxxxxx>
>>> ---
>>> arch/arm/boot/dts/lan966x.dtsi | 55
>>> ++++++++++++++++++++++++++++++++++
>>> 1 file changed, 55 insertions(+)
>>>
>>> diff --git a/arch/arm/boot/dts/lan966x.dtsi
>>> b/arch/arm/boot/dts/lan966x.dtsi
>>> index a7d46a2ca058..bea69b6d2749 100644
>>> --- a/arch/arm/boot/dts/lan966x.dtsi
>>> +++ b/arch/arm/boot/dts/lan966x.dtsi
>>> @@ -92,6 +92,19 @@ flx0: flexcom@e0040000 {
>>> #size-cells = <1>;
>>> ranges = <0x0 0xe0040000 0x800>;
>>> status = "disabled";
>>> +
>>> + usart0: serial@200 {
>>> + compatible =
>>> "atmel,at91sam9260-usart";
>>
>> Are the usart blocks in lan966x 1:1 compatible with what is is sam9260?
>> In
>> case not it may worth to have a new compatible here, for lan966x, such
>> that
>> when new features will be implemented in usart driver for lan966x the
>> old
>> DT (this one) will work with the new kernel implementation.
>
> During my review of the inital dtsi patch, I've asked the same question
> [1]
> and I was told they are the same.
>
> At least this exact usart compatible is already in this file. I was
> under
> the impression, that was the least controversial compatible :)
OK.
>
> But you'll need to tell me if they are the same or not, I don't have
> any clue what microchip has reused.
From software point of view comparing registers should be good, as far as I
can tell. All AT91 datasheet should be available. I though you have checked
one against LAN966. At the moment I don't have a DS for LAN966. I'll find
one and have a look.
> The only thing I can add is that
> there is a version register within the IP blocks which is already used
> in some drivers.
>
>> Same for the rest of the nodes added in this series.
>>
>>> + reg = <0x200 0x200>;
>>> + interrupts = <GIC_SPI 48
>>> IRQ_TYPE_LEVEL_HIGH>;
>>> + dmas = <&dma0 AT91_XDMAC_DT_PERID(3)>,
>>> + <&dma0
>>> AT91_XDMAC_DT_PERID(2)>;
>>
>> Keep dma entries aligned.
>
> Oh shoot. How embarrassing they are alligned when the tab width is 4 *g*
> Thanks.
>
> -michael
>
> [1]
> https://lore.kernel.org/lkml/20220210123704.477826-1-michael@xxxxxxxx/
>
>>> + dma-names = "tx", "rx";
>>> + clocks = <&nic_clk>;
>>> + clock-names = "usart";
>>> + atmel,fifo-size = <32>;
>>> + status = "disabled";
>>> + };
>>> };
>>>
>>> flx1: flexcom@e0044000 {
>>> @@ -102,6 +115,19 @@ flx1: flexcom@e0044000 {
>>> #size-cells = <1>;
>>> ranges = <0x0 0xe0044000 0x800>;
>>> status = "disabled";
>>> +
>>> + usart1: serial@200 {
>>> + compatible =
>>> "atmel,at91sam9260-usart";
>>> + reg = <0x200 0x200>;
>>> + interrupts = <GIC_SPI 49
>>> IRQ_TYPE_LEVEL_HIGH>;
>>> + dmas = <&dma0 AT91_XDMAC_DT_PERID(5)>,
>>> + <&dma0
>>> AT91_XDMAC_DT_PERID(4)>;
>>> + dma-names = "tx", "rx";
>>> + clocks = <&nic_clk>;
>>> + clock-names = "usart";
>>> + atmel,fifo-size = <32>;
>>> + status = "disabled";
>>> + };
>>> };
>>>
>>> trng: rng@e0048000 {
>>> @@ -129,6 +155,19 @@ flx2: flexcom@e0060000 {
>>> #size-cells = <1>;
>>> ranges = <0x0 0xe0060000 0x800>;
>>> status = "disabled";
>>> +
>>> + usart2: serial@200 {
>>> + compatible =
>>> "atmel,at91sam9260-usart";
>>> + reg = <0x200 0x200>;
>>> + interrupts = <GIC_SPI 50
>>> IRQ_TYPE_LEVEL_HIGH>;
>>> + dmas = <&dma0 AT91_XDMAC_DT_PERID(7)>,
>>> + <&dma0
>>> AT91_XDMAC_DT_PERID(6)>;
>>> + dma-names = "tx", "rx";
>>> + clocks = <&nic_clk>;
>>> + clock-names = "usart";
>>> + atmel,fifo-size = <32>;
>>> + status = "disabled";
>>> + };
>>> };
>>>
>>> flx3: flexcom@e0064000 {
>>> @@ -144,6 +183,9 @@ usart3: serial@200 {
>>> compatible =
>>> "atmel,at91sam9260-usart";
>>> reg = <0x200 0x200>;
>>> interrupts = <GIC_SPI 51
>>> IRQ_TYPE_LEVEL_HIGH>;
>>> + dmas = <&dma0 AT91_XDMAC_DT_PERID(9)>,
>>> + <&dma0
>>> AT91_XDMAC_DT_PERID(8)>;
>>> + dma-names = "tx", "rx";
>>> clocks = <&nic_clk>;
>>> clock-names = "usart";
>>> atmel,fifo-size = <32>;
>>> @@ -178,6 +220,19 @@ flx4: flexcom@e0070000 {
>>> #size-cells = <1>;
>>> ranges = <0x0 0xe0070000 0x800>;
>>> status = "disabled";
>>> +
>>> + usart4: serial@200 {
>>> + compatible =
>>> "atmel,at91sam9260-usart";
>>> + reg = <0x200 0x200>;
>>> + interrupts = <GIC_SPI 52
>>> IRQ_TYPE_LEVEL_HIGH>;
>>> + dmas = <&dma0
>>> AT91_XDMAC_DT_PERID(11)>,
>>> + <&dma0
>>> AT91_XDMAC_DT_PERID(10)>;
>>> + dma-names = "tx", "rx";
>>> + clocks = <&nic_clk>;
>>> + clock-names = "usart";
>>> + atmel,fifo-size = <32>;
>>> + status = "disabled";
>>> + };
>>> };
>>>
>>> timer0: timer@e008c000 {
>>> --
>>> 2.30.2
>>>
>
> --
> -michael