Hi Krzysztof Kozlowski, > > > > > -----Original Message----- > > > From: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx> > > > Sent: Saturday, March 9, 2024 1:30 PM > > > Subject: Re: [PATCH 4/4] arm64: dts: renesas: r9a07g0{43,44,54}: > > > Update usbhs family compatible > > > > > > On 09/03/2024 13:32, Biju Das wrote: > > > > Hi Krzysztof Kozlowski, > > > > > > > >> -----Original Message----- > > > >> From: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx> > > > >> Sent: Saturday, March 9, 2024 12:26 PM > > > >> Subject: Re: [PATCH 4/4] arm64: dts: renesas: r9a07g0{43,44,54}: > > > >> Update usbhs family compatible > > > >> > > > >> On 09/03/2024 13:14, Biju Das wrote: > > > >>> Hi Krzysztof Kozlowski, > > > >>> > > > >>> Thanks for the feedback. > > > >>> > > > >>>> -----Original Message----- > > > >>>> From: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx> > > > >>>> Sent: Saturday, March 9, 2024 12:08 PM > > > >>>> Subject: Re: [PATCH 4/4] arm64: dts: renesas: r9a07g0{43,44,54}: > > > >>>> Update usbhs family compatible > > > >>>> > > > >>>> On 08/03/2024 19:09, Biju Das wrote: > > > >>>>> Replace 'renesas,rza2m-usbhs->renesas,rzg2l-usbhs' as family > > > >>>>> compatible for RZ/G2L family SOCs as there is a difference in > > > >>>>> number of pipe buffers compared to RZ/A2M. > > > >>>>> > > > >>>>> Signed-off-by: Biju Das <biju.das.jz@xxxxxxxxxxxxxx> > > > >>>>> --- > > > >>>>> arch/arm64/boot/dts/renesas/r9a07g043.dtsi | 2 +- > > > >>>>> arch/arm64/boot/dts/renesas/r9a07g044.dtsi | 2 +- > > > >>>>> arch/arm64/boot/dts/renesas/r9a07g054.dtsi | 2 +- > > > >>>>> 3 files changed, 3 insertions(+), 3 deletions(-) > > > >>>>> > > > >>>>> diff --git a/arch/arm64/boot/dts/renesas/r9a07g043.dtsi > > > >>>>> b/arch/arm64/boot/dts/renesas/r9a07g043.dtsi > > > >>>>> index 8721f4c9fa0f..766c54b91acc 100644 > > > >>>>> --- a/arch/arm64/boot/dts/renesas/r9a07g043.dtsi > > > >>>>> +++ b/arch/arm64/boot/dts/renesas/r9a07g043.dtsi > > > >>>>> @@ -812,7 +812,7 @@ usb2_phy1: usb-phy@11c70200 { > > > >>>>> > > > >>>>> hsusb: usb@11c60000 { > > > >>>>> compatible = "renesas,usbhs-r9a07g043", > > > >>>>> - "renesas,rza2-usbhs"; > > > >>>>> + "renesas,rzg2l-usbhs"; > > > >>>> > > > >>>> This looks like ABI break and commit msg is quite vague about it. > > > >>> > > > >>> OK, Will update the commit message as driver is taking care of > > > >>> the backward compatibility. > > > >> > > > >> Ah, I was not precise here, you should consider the impact this > > > >> is on DTB used on other kernels. You guys should really stop > > > >> using imprecise/incorrect generic fallbacks and, since it is > > > >> usually tricky to know which fallback is > > > correct or not, you should stop using them at all. > > > > > > > > There will be driver change to handle SoC specific compatible. > > > > > > > > So , > > > > > > > > old DTB + old kernel will have 16 pipe buffers old DTB + newer > > > > kernel will have 9 pipe buffers. > > > > New DTB + new kernel will have 9 pipe buffer. > > > > > > You missed new DTB and old kernel. This breaks all users of DTS. > > > That's the entire point of your broken generic compatibles which you did not address. > > > > As per my knowledge, there is no user in RZ/G2L is using new DTB and old kernel. > > So, it is safe. > > If there is a user for such change, we could use > > compatible = "renesas,usbhs-r9a07g043", > "renesas,rzg2l-usbhs", > "renesas,rza2-usbhs"; > > Or > > compatible = "renesas,usbhs-r9a07g043", > "renesas,rza2-usbhs"; > > > The former consumes less memory compared to the later. > > As later requires, 3 platform structures for rz/g2l, rz/v2l and rz/gul whereas the former requires just > 1. Another way is using RZ/G2L SoC fallback compatible for both RZ/V2L and RZ/Five varients compatible = "renesas,usbhs-r9a07g043", "renesas, usbhs-r9a07g044", "renesas,rza2-usbhs"; This will fit into all ABI combinations with optimized memory usage in driver related to platform structure. old DTB + old kernel will have 16 pipe buffers old DTB + new kernel will have 9 pipe buffers New DTB + old kernel will have 16 pipe buffers New DTB + new kernel will have 9 pipe buffers Cheers, Biju