On 04/04/2023 12:59, Thierry Reding wrote: > On Fri, Mar 31, 2023 at 10:20:16PM +0200, Krzysztof Kozlowski wrote: >> On 31/03/2023 18:31, Thierry Reding wrote: >>> From: Thierry Reding <treding@xxxxxxxxxx> >>> >>> The Jetson Orin Nano is the little sibling of the Jetson Orin NX. >>> Document the corresponding compatible strings for these devices. >>> >>> Signed-off-by: Thierry Reding <treding@xxxxxxxxxx> >>> --- >>> Documentation/devicetree/bindings/arm/tegra.yaml | 7 +++++++ >>> 1 file changed, 7 insertions(+) >>> >>> diff --git a/Documentation/devicetree/bindings/arm/tegra.yaml b/Documentation/devicetree/bindings/arm/tegra.yaml >>> index 61e638c9cad7..60c151da5e06 100644 >>> --- a/Documentation/devicetree/bindings/arm/tegra.yaml >>> +++ b/Documentation/devicetree/bindings/arm/tegra.yaml >>> @@ -220,6 +220,13 @@ properties: >>> - nvidia,p3767-0001 >>> - nvidia,p3767-0002 >>> - const: nvidia,tegra234 >>> + - description: Jetson Orin Nano >>> + items: >>> + - enum: >>> + - nvidia,p3767-0003 >>> + - nvidia,p3767-0004 >>> + - nvidia,p3767-0005 >> >> Similar questions as for patch #1. Where are the DTSes? Where are the >> differences? If we keep documenting every SKU which is the same from >> user/OS perspective, this list would grow crazy. > > Most of the differences will be user-noticeable, even if they can be > runtime detected. Besides the mentioned differences in DRAM size, things > like the number of CPUs, You need different DTS for different number of CPUs. It's not the case we talk here. > GPU compute units or video encoders/decoders I would argue that for these as well you will have different DTS. > can vary depending on the SKU. While the OS should certainly be able to > abstract all of that away as best as possible, on user may still end up > with SKU 3 and another with SKU 5 and it's important for people to know > what they have. Depends. They know what do they have. If the DTS is the same, then it is apparently not important to know what do they have because it is all "the same" (in a compatible meaning). > > So I think we have to find a way to both keep things simple from a DTS > point of view (as I said, we should be able to make do with one DTS file > for the Jetson Orin NX and one for the Jetson Orin Nano with UEFI taking > care of fixing up the DTS per SKU), and not lying to users. If users get > a SKU 3, then that's what we should report instead of 3 (or whatever > ends up being the SKU that we use in the DTS). > > So I want to be as complete as possible in documenting these so that > when people go look for the part numbers, they can at least find some > reference to them. To Chromium guys I need to spend effort to ask to document at least something, as they claim any board compatible bindings are useless for them. It's one border case. Here, I need to bring it to the middle from another side and border case - documenting many unneeded compatibles which do not exist in DTS. It would be much easier if you folks get together and exchange arguments, not through me. :) Let me be clear then for this case: We do not document compatibles for stuff somewhere out-of-tree, just because it is there or you want it to be there. We document the stuff in the kernel or other SW projects. Best regards, Krzysztof
