Re: [PATCH 16/20] dt-bindings: memory: snps: Detach Zynq DDRC controller support

[Krzysztof Kozlowski]

On 23/08/2022 11:32, Serge Semin wrote:
> On Tue, Aug 23, 2022 at 11:17:23AM +0300, Krzysztof Kozlowski wrote:
>> On 22/08/2022 22:07, Serge Semin wrote:
>>> The Zynq A05 DDRC controller has nothing in common with DW uMCTL2 DDRC:
>>> the CSRs layout is absolutely different and it doesn't has IRQ unlike DW
>>> uMCTL2 DDR controller of all versions (v1.x, v2.x and v3.x). Thus there is
>>> no any reason to have these controllers described by the same bindings.
>>> Thus let's split them up.
>>>
>>> While at it rename the original Synopsys uMCTL2 DT-schema file to a more
>>> descriptive - snps,dw-umctl2-ddrc.yaml and add a more detailed title and
>>> description of the device bindings.
>>
> 
>> Filename should be based on compatible, so if renaming then
>> snps,ddrc-3.80a.yaml or snps,ddrc.yaml... which leads to original
>> filename anyway. Therefore nack for rename.
> 
> New requirement? I've submitted not a single patch to the DT-bindings
> sources and didn't get any comment from Rob about that. 

This is not a new requirement. It has been since some time and Rob gave
such reviews.

https://lore.kernel.org/linux-devicetree/YlhkwvGdcf4ozTzG@xxxxxxxxxxxxxxxxxx/

For devices with multiple compatibles that's a bit tricky, but assuming
the bindings describe both original design from Synopsys and it's
implementations, then something closer to Synopsys makes sense.


> In addition
> There are DT bindings with names different from what is defined in the
> compatible name. Moreover there are tons of bindings with various
> compatible names. What name to choose then? Finally the current name
> is too generic to use for actual DW uMCTL2 DDRC controller.

There are thousands of bugs, inconsistencies, naming differences in
kernel. I don't find these as arguments to repeat the practice...so the
bindings file name should be based on the compatible.

Best regards,
Krzysztof