Re: [PATCH v2 00/20] Add minimal Tensor/GS101 SoC support and Oriole/Pixel6 board

Krzysztof Kozlowski
2023-11-05T13:14:34Z

On 05/11/2023 14:08, Greg KH wrote:
> On Sun, Nov 05, 2023 at 01:52:22PM +0100, Krzysztof Kozlowski wrote:
>> On 03/11/2023 18:36, William McVicker wrote:
>>
>>>>
>>>> That's indeed a problem. Future Tesla SoC might have just few pieces
>>>> similar to FSD. There would be no common SoC part, except the actual
>>>> Tesla IP.
>>>>
>>>> Same for Google. Future GSXXX, if done by Qualcomm, will be absolutely
>>>> different than GS101 and the only common part would be the TPU (Tensor).
>>>>
>>>> So now let's decide what is the common denominator:
>>>> 1. Core SoC architecture, like buses, pinctrl, clocks, timers, serial,
>>>> and many IP blocks, which constitute 95% of Devicetree bindings and drivers,
>>>> 2. The one, big piece made by Samsung's customer: TPU, NPU or whatever.
>>>
>>> As mentioned above, I think this should be based on how the DTBs and DTBOs are
>>> used and distributed.
>>
>> None of existing platforms do it. Nowhere. All chromebooks are split per
>> SoC, not "how DTBs should be used and distributed". There is no google,
>> no Chromebook directory. None of Samsung phones have it. No
>> Samsung-phone directory. None of Google phones have Pixel directory.
>
> but for code we have:
> drivers/patform/chrome/
> drivers/firmware/google/
> drivers/net/ethernet/google/
>
> don't know if that matters or not, but thought I would mention it...

Yes, for the drivers for the similar hardware we have it. We have
drivers for Chromebook's Embedded Controller - let's put it in one
place, so that maintenance and review will be easier.

Now for DTS, the common hardware is not "Samsung phones", but "Samsung
SoC". We organize it like:
1. Samsung phones with Samsung SoC -> arm64/dts/samsung
2. Samsung phones with Qualcomm SoC -> arm64/dts/qcom

because the main common part is the SoC, not the rest of the phone.
There is no reviewer or maintainer for Samsung phones. There is no need
for such. No benefits, almost not many common parts except some touchscreen.

Why Google Pixel suddenly should be exception from the way we handle DTS
of all ARM64 platforms?

Best regards,
Krzysztof