| Message ID | 20230620000349.2122191-1-nfraprado@collabora.com |
|---|---|
| Headers | show |
| Series | Enable decoder for mt8183 | expand |
On 21/06/2023 20:00, Nícolas F. R. A. Prado wrote: >> >> But anyway this variant comes with some set of regs and reg-names. Other >> variant comes with different set. In all cases they should be defined, >> even by "defined" means not allowed. > > I'm not sure what you mean. Are you suggesting to disable reg-names on mt8173? That's one of the options if for some reason you don't want to define them. > >> >>> >>> But in a separate series we could drop vdecsys from mt8173's reg as well, >>> passing it as a syscon instead, which would solve the warning on that platform, >>> though some more driver changes would be needed to be able to handle it for that >>> SoC. The newer SoCs like mt8192, mt8195, etc, should also get vdecsys dropped >>> from their regs to have a correct memory description. >>> >> >> Sure, but I don't understand how does it affect defining and making >> specific regs/reg-names or keeping them loose. > > We need some way to tell in the driver whether the first reg is VDEC_SYS or not. > Since so far reg-names have not been used for the vcodec, the simplest, and > cleanest, way to do it, is to add reg-names when VDEC_SYS is not present. When > the other SoCs are updated to no longer have the first reg as VDEC_SYS, they > would also have reg-names added to their binding, to clearly indicate that. Don't use reg-names for that. The order of entries is anyway strict. > > For example, for mt8173 we currently have > > vcodec_dec: vcodec@16000000 { > compatible = "mediatek,mt8173-vcodec-dec"; > reg = <0 0x16000000 0 0x100>, /* VDEC_SYS */ > <0 0x16020000 0 0x1000>, /* VDEC_MISC */ > <0 0x16021000 0 0x800>, /* VDEC_LD */ > <0 0x16021800 0 0x800>, /* VDEC_TOP */ > <0 0x16022000 0 0x1000>, /* VDEC_CM */ > <0 0x16023000 0 0x1000>, /* VDEC_AD */ > <0 0x16024000 0 0x1000>, /* VDEC_AV */ > <0 0x16025000 0 0x1000>, /* VDEC_PP */ > <0 0x16026800 0 0x800>, /* VDEC_HWD */ > <0 0x16027000 0 0x800>, /* VDEC_HWQ */ > <0 0x16027800 0 0x800>, /* VDEC_HWB */ > <0 0x16028400 0 0x400>; /* VDEC_HWG */ > > In a future series, when removing VDEC_SYS from it, it would become > > vcodec_dec: vcodec@16020000 { > compatible = "mediatek,mt8173-vcodec-dec"; > reg = <0 0x16020000 0 0x1000>, /* VDEC_MISC */ > <0 0x16021000 0 0x800>, /* VDEC_LD */ > <0 0x16021800 0 0x800>, /* VDEC_TOP */ > <0 0x16022000 0 0x1000>, /* VDEC_CM */ > <0 0x16023000 0 0x1000>, /* VDEC_AD */ > <0 0x16024000 0 0x1000>, /* VDEC_AV */ > <0 0x16025000 0 0x1000>, /* VDEC_PP */ > <0 0x16026800 0 0x800>, /* VDEC_HWD */ > <0 0x16027000 0 0x800>, /* VDEC_HWQ */ > <0 0x16027800 0 0x800>, /* VDEC_HWB */ > <0 0x16028400 0 0x400>; /* VDEC_HWG */ > reg-names = "misc", "ld", "top", "cm", "ad", "av", "pp", > "hwd", "hwq", "hwb", "hwg"; So you want to use reg-names to avoid ABI break. This is not the reason not to define reg-names for other case. Best regards, Krzysztof
On 26/06/2023 15:54, Nícolas F. R. A. Prado wrote: > On Fri, Jun 23, 2023 at 06:21:31PM +0200, Krzysztof Kozlowski wrote: >> On 21/06/2023 20:00, Nícolas F. R. A. Prado wrote: >>>> >>>> But anyway this variant comes with some set of regs and reg-names. Other >>>> variant comes with different set. In all cases they should be defined, >>>> even by "defined" means not allowed. >>> >>> I'm not sure what you mean. Are you suggesting to disable reg-names on mt8173? >> >> That's one of the options if for some reason you don't want to define them. >> >>> >>>> >>>>> >>>>> But in a separate series we could drop vdecsys from mt8173's reg as well, >>>>> passing it as a syscon instead, which would solve the warning on that platform, >>>>> though some more driver changes would be needed to be able to handle it for that >>>>> SoC. The newer SoCs like mt8192, mt8195, etc, should also get vdecsys dropped >>>>> from their regs to have a correct memory description. >>>>> >>>> >>>> Sure, but I don't understand how does it affect defining and making >>>> specific regs/reg-names or keeping them loose. >>> >>> We need some way to tell in the driver whether the first reg is VDEC_SYS or not. >>> Since so far reg-names have not been used for the vcodec, the simplest, and >>> cleanest, way to do it, is to add reg-names when VDEC_SYS is not present. When >>> the other SoCs are updated to no longer have the first reg as VDEC_SYS, they >>> would also have reg-names added to their binding, to clearly indicate that. >> >> Don't use reg-names for that. The order of entries is anyway strict. > > Since the order of entries is strict, if I remove VDEC_SYS from mt8183, I also > need to remove it from mt8173, is that what you mean? It's different compatible, so it can have different entries. > I would still check for > the presence of reg-names in the driver to differentiate whether the old or new > binding is used, you just don't want different reg-names between compatibles in > the binding? I wrote already what I want: In all cases they should be defined, even by "defined" means not allowed. Now of course the best would be if the reg-names are always the same, at least in respect of order of items. This is what we try to do for all devices. > >> >>> >>> For example, for mt8173 we currently have >>> >>> vcodec_dec: vcodec@16000000 { >>> compatible = "mediatek,mt8173-vcodec-dec"; >>> reg = <0 0x16000000 0 0x100>, /* VDEC_SYS */ >>> <0 0x16020000 0 0x1000>, /* VDEC_MISC */ >>> <0 0x16021000 0 0x800>, /* VDEC_LD */ >>> <0 0x16021800 0 0x800>, /* VDEC_TOP */ >>> <0 0x16022000 0 0x1000>, /* VDEC_CM */ >>> <0 0x16023000 0 0x1000>, /* VDEC_AD */ >>> <0 0x16024000 0 0x1000>, /* VDEC_AV */ >>> <0 0x16025000 0 0x1000>, /* VDEC_PP */ >>> <0 0x16026800 0 0x800>, /* VDEC_HWD */ >>> <0 0x16027000 0 0x800>, /* VDEC_HWQ */ >>> <0 0x16027800 0 0x800>, /* VDEC_HWB */ >>> <0 0x16028400 0 0x400>; /* VDEC_HWG */ >>> >>> In a future series, when removing VDEC_SYS from it, it would become >>> >>> vcodec_dec: vcodec@16020000 { >>> compatible = "mediatek,mt8173-vcodec-dec"; >>> reg = <0 0x16020000 0 0x1000>, /* VDEC_MISC */ >>> <0 0x16021000 0 0x800>, /* VDEC_LD */ >>> <0 0x16021800 0 0x800>, /* VDEC_TOP */ >>> <0 0x16022000 0 0x1000>, /* VDEC_CM */ >>> <0 0x16023000 0 0x1000>, /* VDEC_AD */ >>> <0 0x16024000 0 0x1000>, /* VDEC_AV */ >>> <0 0x16025000 0 0x1000>, /* VDEC_PP */ >>> <0 0x16026800 0 0x800>, /* VDEC_HWD */ >>> <0 0x16027000 0 0x800>, /* VDEC_HWQ */ >>> <0 0x16027800 0 0x800>, /* VDEC_HWB */ >>> <0 0x16028400 0 0x400>; /* VDEC_HWG */ >>> reg-names = "misc", "ld", "top", "cm", "ad", "av", "pp", >>> "hwd", "hwq", "hwb", "hwg"; >> >> So you want to use reg-names to avoid ABI break. This is not the reason >> not to define reg-names for other case. > > There will be an ABI break anyway when the first reg is removed (as shown > above), I'm just trying to avoid churn: adding a reg-name that will be removed > later. So remove the reg-name now and there will be no "later"? Best regards, Krzysztof