On 16/06/2023 10:24, Miquel Raynal wrote: > Hi Krzysztof, > > krzysztof.kozlowski@xxxxxxxxxx wrote on Fri, 16 Jun 2023 10:15:31 +0200: > >> On 15/06/2023 23:06, Chris Packham wrote: >>>> >>>>> + >>>>> +properties: >>>>> + compatible: >>>>> + oneOf: >>>>> + - items: >>>>> + - const: marvell,armada-8k-nand-controller >>>>> + - const: marvell,armada370-nand-controller >>>>> + - enum: >>>>> + - marvell,armada-8k-nand-controller >>>> This is wrong. 8k cannot be both: compatible and not compatible with >>>> 370. It's not someone's cat to be in both states at the same time... >>> >>> The correct state (IMHO, Miquel correct me if I'm wrong) is `compatible >>> = "marvell,armada-8k-nand-controller";` as there are some 8K specific >>> requirements that aren't present on the 370 (specifically the >>> system-controller and the 2nd clock). >> >> Presence of specific requirements does not invalidate compatibility. Two >> devices are compatible if the 8k can bind and work with 370 compatible >> string, even if this means some lower performance or less features (e.g. >> subset of features). > > Quoting myself from 2019 (comment in the driver): > "Some SoCs like A7k/A8k need to enable manually the NAND controller, > gated clocks and reset bits to avoid being bootloader dependent." > > So can the 8k controller work using a 370 compatible : yes, if the > booloader enabled the NAND controller already, no otherwise. But in > practice it is the same controller. > > Given this information I don't know whether it makes sense to qualify > the 8k controller compatible with the 370 compatible or not. Indeed, a bit tricky decision. For me they could stay compatible, because apparently programming model is the same or similar. Best regards, Krzysztof
