| Message ID | 20220617222916.2435618-3-nfraprado@collabora.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Fixes for dtbs_check warnings on Mediatek XHCI nodes | expand |
On 17/06/2022 15:29, Nícolas F. R. A. Prado wrote: > The current clock list in the binding doesn't allow for one of the > optional clocks to be missing and a subsequent clock to be present. An > example where this is an issue is in mt8192.dtsi, which has "sys_ck", > "ref_ck", "xhci_ck" and would cause dtbs_check warnings. > > Change the clock list in a way that allows the middle optional clocks to > be missing, while still guaranteeing a fixed order. The "ref_ck" is kept > as a const even though it is optional for simplicity, since it is > present in all current dts files. > > Signed-off-by: Nícolas F. R. A. Prado <nfraprado@collabora.com> > --- > > .../devicetree/bindings/usb/mediatek,mtk-xhci.yaml | 9 +++++++-- > 1 file changed, 7 insertions(+), 2 deletions(-) > > diff --git a/Documentation/devicetree/bindings/usb/mediatek,mtk-xhci.yaml b/Documentation/devicetree/bindings/usb/mediatek,mtk-xhci.yaml > index 63cbc2b62d18..99a1b233ec90 100644 > --- a/Documentation/devicetree/bindings/usb/mediatek,mtk-xhci.yaml > +++ b/Documentation/devicetree/bindings/usb/mediatek,mtk-xhci.yaml > @@ -80,8 +80,13 @@ properties: > items: > - const: sys_ck # required, the following ones are optional > - const: ref_ck > - - const: mcu_ck > - - const: dma_ck > + - enum: > + - mcu_ck > + - dma_ck > + - xhci_ck > + - enum: > + - dma_ck > + - xhci_ck > - const: xhci_ck You allow now almost any order here, including incorrect like sys,ref,xhci,xhci,xhci. The order of clocks has to be fixed and we cannot allow flexibility. Are you sure that these clocks are actually optional (not wired to the device)? Best regards, Krzysztof
On Fri, 2022-06-17 at 18:29 -0400, Nícolas F. R. A. Prado wrote: > The current clock list in the binding doesn't allow for one of the > optional clocks to be missing and a subsequent clock to be present. > An > example where this is an issue is in mt8192.dtsi, which has "sys_ck", > "ref_ck", "xhci_ck" and would cause dtbs_check warnings. How about using fixed clock instead to fix the check warning? Using enum way seems make it more complex. > > Change the clock list in a way that allows the middle optional clocks > to > be missing, while still guaranteeing a fixed order. The "ref_ck" is > kept > as a const even though it is optional for simplicity, since it is > present in all current dts files. > > Signed-off-by: Nícolas F. R. A. Prado <nfraprado@collabora.com> > --- > > .../devicetree/bindings/usb/mediatek,mtk-xhci.yaml | 9 > +++++++-- > 1 file changed, 7 insertions(+), 2 deletions(-) > > diff --git a/Documentation/devicetree/bindings/usb/mediatek,mtk- > xhci.yaml b/Documentation/devicetree/bindings/usb/mediatek,mtk- > xhci.yaml > index 63cbc2b62d18..99a1b233ec90 100644 > --- a/Documentation/devicetree/bindings/usb/mediatek,mtk-xhci.yaml > +++ b/Documentation/devicetree/bindings/usb/mediatek,mtk-xhci.yaml > @@ -80,8 +80,13 @@ properties: > items: > - const: sys_ck # required, the following ones are optional > - const: ref_ck > - - const: mcu_ck > - - const: dma_ck > + - enum: > + - mcu_ck > + - dma_ck > + - xhci_ck > + - enum: > + - dma_ck > + - xhci_ck > - const: xhci_ck > > assigned-clocks:
On Fri, 2022-06-17 at 18:25 -0700, Krzysztof Kozlowski wrote: > On 17/06/2022 15:29, Nícolas F. R. A. Prado wrote: > > The current clock list in the binding doesn't allow for one of the > > optional clocks to be missing and a subsequent clock to be present. > > An > > example where this is an issue is in mt8192.dtsi, which has > > "sys_ck", > > "ref_ck", "xhci_ck" and would cause dtbs_check warnings. > > > > Change the clock list in a way that allows the middle optional > > clocks to > > be missing, while still guaranteeing a fixed order. The "ref_ck" is > > kept > > as a const even though it is optional for simplicity, since it is > > present in all current dts files. > > > > Signed-off-by: Nícolas F. R. A. Prado <nfraprado@collabora.com> > > --- > > > > .../devicetree/bindings/usb/mediatek,mtk-xhci.yaml | 9 > > +++++++-- > > 1 file changed, 7 insertions(+), 2 deletions(-) > > > > diff --git a/Documentation/devicetree/bindings/usb/mediatek,mtk- > > xhci.yaml b/Documentation/devicetree/bindings/usb/mediatek,mtk- > > xhci.yaml > > index 63cbc2b62d18..99a1b233ec90 100644 > > --- a/Documentation/devicetree/bindings/usb/mediatek,mtk-xhci.yaml > > +++ b/Documentation/devicetree/bindings/usb/mediatek,mtk-xhci.yaml > > @@ -80,8 +80,13 @@ properties: > > items: > > - const: sys_ck # required, the following ones are optional > > - const: ref_ck > > - - const: mcu_ck > > - - const: dma_ck > > + - enum: > > + - mcu_ck > > + - dma_ck > > + - xhci_ck > > + - enum: > > + - dma_ck > > + - xhci_ck > > - const: xhci_ck > > You allow now almost any order here, including incorrect like > sys,ref,xhci,xhci,xhci. > > The order of clocks has to be fixed and we cannot allow flexibility. > Are > you sure that these clocks are actually optional (not wired to the > device)? In fact, these optional clocks are fixed, due to no gates are provided, SW can't control them by CCF; In this case, I usually use a fixed clock, or ignore it. > > > Best regards, > Krzysztof
On 19/06/2022 09:40, Chunfeng Yun wrote: > On Fri, 2022-06-17 at 18:29 -0400, Nícolas F. R. A. Prado wrote: >> The current clock list in the binding doesn't allow for one of the >> optional clocks to be missing and a subsequent clock to be present. >> An >> example where this is an issue is in mt8192.dtsi, which has "sys_ck", >> "ref_ck", "xhci_ck" and would cause dtbs_check warnings. > How about using fixed clock instead to fix the check warning? > Using enum way seems make it more complex. > That would mean the clock is not actually optional. The DTS should reflect the hardware so either you have the clock there or not. Either it is an input or not. Of course there are some exceptions (like non-controllable clock or regulator which not always has to be modeled). Best regards, Krzysztof
On 19/06/2022 09:46, Chunfeng Yun wrote: > On Fri, 2022-06-17 at 18:25 -0700, Krzysztof Kozlowski wrote: >> On 17/06/2022 15:29, Nícolas F. R. A. Prado wrote: >>> The current clock list in the binding doesn't allow for one of the >>> optional clocks to be missing and a subsequent clock to be present. >>> An >>> example where this is an issue is in mt8192.dtsi, which has >>> "sys_ck", >>> "ref_ck", "xhci_ck" and would cause dtbs_check warnings. >>> >>> Change the clock list in a way that allows the middle optional >>> clocks to >>> be missing, while still guaranteeing a fixed order. The "ref_ck" is >>> kept >>> as a const even though it is optional for simplicity, since it is >>> present in all current dts files. >>> >>> Signed-off-by: Nícolas F. R. A. Prado <nfraprado@collabora.com> >>> --- >>> >>> .../devicetree/bindings/usb/mediatek,mtk-xhci.yaml | 9 >>> +++++++-- >>> 1 file changed, 7 insertions(+), 2 deletions(-) >>> >>> diff --git a/Documentation/devicetree/bindings/usb/mediatek,mtk- >>> xhci.yaml b/Documentation/devicetree/bindings/usb/mediatek,mtk- >>> xhci.yaml >>> index 63cbc2b62d18..99a1b233ec90 100644 >>> --- a/Documentation/devicetree/bindings/usb/mediatek,mtk-xhci.yaml >>> +++ b/Documentation/devicetree/bindings/usb/mediatek,mtk-xhci.yaml >>> @@ -80,8 +80,13 @@ properties: >>> items: >>> - const: sys_ck # required, the following ones are optional >>> - const: ref_ck >>> - - const: mcu_ck >>> - - const: dma_ck >>> + - enum: >>> + - mcu_ck >>> + - dma_ck >>> + - xhci_ck >>> + - enum: >>> + - dma_ck >>> + - xhci_ck >>> - const: xhci_ck >> >> You allow now almost any order here, including incorrect like >> sys,ref,xhci,xhci,xhci. >> >> The order of clocks has to be fixed and we cannot allow flexibility. >> Are >> you sure that these clocks are actually optional (not wired to the >> device)? > In fact, these optional clocks are fixed, due to no gates are provided, > SW can't control them by CCF; > In this case, I usually use a fixed clock, or ignore it. But in some versions these clocks are controllable or not? Best regards, Krzysztof
On Sun, 2022-06-19 at 14:05 +0200, Krzysztof Kozlowski wrote: > On 19/06/2022 09:46, Chunfeng Yun wrote: > > On Fri, 2022-06-17 at 18:25 -0700, Krzysztof Kozlowski wrote: > > > On 17/06/2022 15:29, Nícolas F. R. A. Prado wrote: > > > > The current clock list in the binding doesn't allow for one of > > > > the > > > > optional clocks to be missing and a subsequent clock to be > > > > present. > > > > An > > > > example where this is an issue is in mt8192.dtsi, which has > > > > "sys_ck", > > > > "ref_ck", "xhci_ck" and would cause dtbs_check warnings. > > > > > > > > Change the clock list in a way that allows the middle optional > > > > clocks to > > > > be missing, while still guaranteeing a fixed order. The > > > > "ref_ck" is > > > > kept > > > > as a const even though it is optional for simplicity, since it > > > > is > > > > present in all current dts files. > > > > > > > > Signed-off-by: Nícolas F. R. A. Prado <nfraprado@collabora.com> > > > > --- > > > > > > > > .../devicetree/bindings/usb/mediatek,mtk-xhci.yaml | 9 > > > > +++++++-- > > > > 1 file changed, 7 insertions(+), 2 deletions(-) > > > > > > > > diff --git > > > > a/Documentation/devicetree/bindings/usb/mediatek,mtk- > > > > xhci.yaml b/Documentation/devicetree/bindings/usb/mediatek,mtk- > > > > xhci.yaml > > > > index 63cbc2b62d18..99a1b233ec90 100644 > > > > --- a/Documentation/devicetree/bindings/usb/mediatek,mtk- > > > > xhci.yaml > > > > +++ b/Documentation/devicetree/bindings/usb/mediatek,mtk- > > > > xhci.yaml > > > > @@ -80,8 +80,13 @@ properties: > > > > items: > > > > - const: sys_ck # required, the following ones are > > > > optional > > > > - const: ref_ck > > > > - - const: mcu_ck > > > > - - const: dma_ck > > > > + - enum: > > > > + - mcu_ck > > > > + - dma_ck > > > > + - xhci_ck > > > > + - enum: > > > > + - dma_ck > > > > + - xhci_ck > > > > - const: xhci_ck > > > > > > You allow now almost any order here, including incorrect like > > > sys,ref,xhci,xhci,xhci. > > > > > > The order of clocks has to be fixed and we cannot allow > > > flexibility. > > > Are > > > you sure that these clocks are actually optional (not wired to > > > the > > > device)? > > > > In fact, these optional clocks are fixed, due to no gates are > > provided, > > SW can't control them by CCF; > > In this case, I usually use a fixed clock, or ignore it. > > But in some versions these clocks are controllable or not? Some SoCs are controllable, some ones are not (fixed clock). > > Best regards, > Krzysztof
On 20/06/2022 08:59, Chunfeng Yun wrote: > On Sun, 2022-06-19 at 14:05 +0200, Krzysztof Kozlowski wrote: >> On 19/06/2022 09:46, Chunfeng Yun wrote: >>> On Fri, 2022-06-17 at 18:25 -0700, Krzysztof Kozlowski wrote: >>>> On 17/06/2022 15:29, Nícolas F. R. A. Prado wrote: >>>>> The current clock list in the binding doesn't allow for one of >>>>> the >>>>> optional clocks to be missing and a subsequent clock to be >>>>> present. >>>>> An >>>>> example where this is an issue is in mt8192.dtsi, which has >>>>> "sys_ck", >>>>> "ref_ck", "xhci_ck" and would cause dtbs_check warnings. >>>>> >>>>> Change the clock list in a way that allows the middle optional >>>>> clocks to >>>>> be missing, while still guaranteeing a fixed order. The >>>>> "ref_ck" is >>>>> kept >>>>> as a const even though it is optional for simplicity, since it >>>>> is >>>>> present in all current dts files. >>>>> >>>>> Signed-off-by: Nícolas F. R. A. Prado <nfraprado@collabora.com> >>>>> --- >>>>> >>>>> .../devicetree/bindings/usb/mediatek,mtk-xhci.yaml | 9 >>>>> +++++++-- >>>>> 1 file changed, 7 insertions(+), 2 deletions(-) >>>>> >>>>> diff --git >>>>> a/Documentation/devicetree/bindings/usb/mediatek,mtk- >>>>> xhci.yaml b/Documentation/devicetree/bindings/usb/mediatek,mtk- >>>>> xhci.yaml >>>>> index 63cbc2b62d18..99a1b233ec90 100644 >>>>> --- a/Documentation/devicetree/bindings/usb/mediatek,mtk- >>>>> xhci.yaml >>>>> +++ b/Documentation/devicetree/bindings/usb/mediatek,mtk- >>>>> xhci.yaml >>>>> @@ -80,8 +80,13 @@ properties: >>>>> items: >>>>> - const: sys_ck # required, the following ones are >>>>> optional >>>>> - const: ref_ck >>>>> - - const: mcu_ck >>>>> - - const: dma_ck >>>>> + - enum: >>>>> + - mcu_ck >>>>> + - dma_ck >>>>> + - xhci_ck >>>>> + - enum: >>>>> + - dma_ck >>>>> + - xhci_ck >>>>> - const: xhci_ck >>>> >>>> You allow now almost any order here, including incorrect like >>>> sys,ref,xhci,xhci,xhci. >>>> >>>> The order of clocks has to be fixed and we cannot allow >>>> flexibility. >>>> Are >>>> you sure that these clocks are actually optional (not wired to >>>> the >>>> device)? >>> >>> In fact, these optional clocks are fixed, due to no gates are >>> provided, >>> SW can't control them by CCF; >>> In this case, I usually use a fixed clock, or ignore it. >> >> But in some versions these clocks are controllable or not? > Some SoCs are controllable, some ones are not (fixed clock). Thanks for confirming. Then I would prefer to make these clocks required (not optional) and always provide them - via common clock framework or fixed-clock. Best regards, Krzysztof
On Mon, Jun 20, 2022 at 10:50:57AM +0200, Krzysztof Kozlowski wrote: > On 20/06/2022 08:59, Chunfeng Yun wrote: > > On Sun, 2022-06-19 at 14:05 +0200, Krzysztof Kozlowski wrote: > >> On 19/06/2022 09:46, Chunfeng Yun wrote: > >>> On Fri, 2022-06-17 at 18:25 -0700, Krzysztof Kozlowski wrote: > >>>> On 17/06/2022 15:29, Nícolas F. R. A. Prado wrote: > >>>>> The current clock list in the binding doesn't allow for one of > >>>>> the > >>>>> optional clocks to be missing and a subsequent clock to be > >>>>> present. > >>>>> An > >>>>> example where this is an issue is in mt8192.dtsi, which has > >>>>> "sys_ck", > >>>>> "ref_ck", "xhci_ck" and would cause dtbs_check warnings. > >>>>> > >>>>> Change the clock list in a way that allows the middle optional > >>>>> clocks to > >>>>> be missing, while still guaranteeing a fixed order. The > >>>>> "ref_ck" is > >>>>> kept > >>>>> as a const even though it is optional for simplicity, since it > >>>>> is > >>>>> present in all current dts files. > >>>>> > >>>>> Signed-off-by: Nícolas F. R. A. Prado <nfraprado@collabora.com> > >>>>> --- > >>>>> > >>>>> .../devicetree/bindings/usb/mediatek,mtk-xhci.yaml | 9 > >>>>> +++++++-- > >>>>> 1 file changed, 7 insertions(+), 2 deletions(-) > >>>>> > >>>>> diff --git > >>>>> a/Documentation/devicetree/bindings/usb/mediatek,mtk- > >>>>> xhci.yaml b/Documentation/devicetree/bindings/usb/mediatek,mtk- > >>>>> xhci.yaml > >>>>> index 63cbc2b62d18..99a1b233ec90 100644 > >>>>> --- a/Documentation/devicetree/bindings/usb/mediatek,mtk- > >>>>> xhci.yaml > >>>>> +++ b/Documentation/devicetree/bindings/usb/mediatek,mtk- > >>>>> xhci.yaml > >>>>> @@ -80,8 +80,13 @@ properties: > >>>>> items: > >>>>> - const: sys_ck # required, the following ones are > >>>>> optional > >>>>> - const: ref_ck > >>>>> - - const: mcu_ck > >>>>> - - const: dma_ck > >>>>> + - enum: > >>>>> + - mcu_ck > >>>>> + - dma_ck > >>>>> + - xhci_ck > >>>>> + - enum: > >>>>> + - dma_ck > >>>>> + - xhci_ck > >>>>> - const: xhci_ck > >>>> > >>>> You allow now almost any order here, including incorrect like > >>>> sys,ref,xhci,xhci,xhci. > >>>> > >>>> The order of clocks has to be fixed and we cannot allow > >>>> flexibility. > >>>> Are > >>>> you sure that these clocks are actually optional (not wired to > >>>> the > >>>> device)? > >>> > >>> In fact, these optional clocks are fixed, due to no gates are > >>> provided, > >>> SW can't control them by CCF; > >>> In this case, I usually use a fixed clock, or ignore it. > >> > >> But in some versions these clocks are controllable or not? > > Some SoCs are controllable, some ones are not (fixed clock). > > Thanks for confirming. Then I would prefer to make these clocks required > (not optional) and always provide them - via common clock framework or > fixed-clock. Hi Krzysztof and Chunfeng, thank you both for the feedback. Since the solution I proposed in this patch is not acceptable I see two options: 1. Split the clocks in several if blocks matched by compatibles 2. Make the clocks required and use fixed-clock nodes for the missing clocks in the DT My understanding is that 1 is the desirable solution if the clock is really missing in some hardware variants, while 2 is desirable if all hardware variants really receive all the clocks, only that on some variants they're fixed and not controlable by SW. From what I'm reading of this discussion it seems that the latter is the case here and thus we should go for 2. Is this correct? Also Chunfeng, do you have information on whether the same is true for the MMC HW block? I recently submitted some changes to that binding [1] but I followed approach 1 there instead. However if all the clocks are present in the HW level there as well it would make more sense for me to change it to follow approach 2. Thanks, Nícolas [1] https://lore.kernel.org/all/20220617230114.2438875-1-nfraprado@collabora.com
On 20/06/2022 17:50, Nícolas F. R. A. Prado wrote: > On Mon, Jun 20, 2022 at 10:50:57AM +0200, Krzysztof Kozlowski wrote: >> On 20/06/2022 08:59, Chunfeng Yun wrote: >>> On Sun, 2022-06-19 at 14:05 +0200, Krzysztof Kozlowski wrote: >>>> On 19/06/2022 09:46, Chunfeng Yun wrote: >>>>> On Fri, 2022-06-17 at 18:25 -0700, Krzysztof Kozlowski wrote: >>>>>> On 17/06/2022 15:29, Nícolas F. R. A. Prado wrote: >>>>>>> The current clock list in the binding doesn't allow for one of >>>>>>> the >>>>>>> optional clocks to be missing and a subsequent clock to be >>>>>>> present. >>>>>>> An >>>>>>> example where this is an issue is in mt8192.dtsi, which has >>>>>>> "sys_ck", >>>>>>> "ref_ck", "xhci_ck" and would cause dtbs_check warnings. >>>>>>> >>>>>>> Change the clock list in a way that allows the middle optional >>>>>>> clocks to >>>>>>> be missing, while still guaranteeing a fixed order. The >>>>>>> "ref_ck" is >>>>>>> kept >>>>>>> as a const even though it is optional for simplicity, since it >>>>>>> is >>>>>>> present in all current dts files. >>>>>>> >>>>>>> Signed-off-by: Nícolas F. R. A. Prado <nfraprado@collabora.com> >>>>>>> --- >>>>>>> >>>>>>> .../devicetree/bindings/usb/mediatek,mtk-xhci.yaml | 9 >>>>>>> +++++++-- >>>>>>> 1 file changed, 7 insertions(+), 2 deletions(-) >>>>>>> >>>>>>> diff --git >>>>>>> a/Documentation/devicetree/bindings/usb/mediatek,mtk- >>>>>>> xhci.yaml b/Documentation/devicetree/bindings/usb/mediatek,mtk- >>>>>>> xhci.yaml >>>>>>> index 63cbc2b62d18..99a1b233ec90 100644 >>>>>>> --- a/Documentation/devicetree/bindings/usb/mediatek,mtk- >>>>>>> xhci.yaml >>>>>>> +++ b/Documentation/devicetree/bindings/usb/mediatek,mtk- >>>>>>> xhci.yaml >>>>>>> @@ -80,8 +80,13 @@ properties: >>>>>>> items: >>>>>>> - const: sys_ck # required, the following ones are >>>>>>> optional >>>>>>> - const: ref_ck >>>>>>> - - const: mcu_ck >>>>>>> - - const: dma_ck >>>>>>> + - enum: >>>>>>> + - mcu_ck >>>>>>> + - dma_ck >>>>>>> + - xhci_ck >>>>>>> + - enum: >>>>>>> + - dma_ck >>>>>>> + - xhci_ck >>>>>>> - const: xhci_ck >>>>>> >>>>>> You allow now almost any order here, including incorrect like >>>>>> sys,ref,xhci,xhci,xhci. >>>>>> >>>>>> The order of clocks has to be fixed and we cannot allow >>>>>> flexibility. >>>>>> Are >>>>>> you sure that these clocks are actually optional (not wired to >>>>>> the >>>>>> device)? >>>>> >>>>> In fact, these optional clocks are fixed, due to no gates are >>>>> provided, >>>>> SW can't control them by CCF; >>>>> In this case, I usually use a fixed clock, or ignore it. >>>> >>>> But in some versions these clocks are controllable or not? >>> Some SoCs are controllable, some ones are not (fixed clock). >> >> Thanks for confirming. Then I would prefer to make these clocks required >> (not optional) and always provide them - via common clock framework or >> fixed-clock. > > Hi Krzysztof and Chunfeng, > > thank you both for the feedback. > > Since the solution I proposed in this patch is not acceptable I see two options: > 1. Split the clocks in several if blocks matched by compatibles > 2. Make the clocks required and use fixed-clock nodes for the missing clocks in > the DT > > My understanding is that 1 is the desirable solution if the clock is really > missing in some hardware variants, while 2 is desirable if all hardware variants > really receive all the clocks, only that on some variants they're fixed and not > controlable by SW. > > From what I'm reading of this discussion it seems that the latter is the case > here and thus we should go for 2. Is this correct? This is how I understood it as well, so correct from my side. > > Also Chunfeng, do you have information on whether the same is true for the MMC > HW block? I recently submitted some changes to that binding [1] but I followed > approach 1 there instead. However if all the clocks are present in the HW level > there as well it would make more sense for me to change it to follow approach 2. > > Thanks, > Nícolas > > [1] https://lore.kernel.org/all/20220617230114.2438875-1-nfraprado@collabora.com Best regards, Krzysztof
On Tue, 2022-06-21 at 09:14 +0200, Krzysztof Kozlowski wrote: > On 20/06/2022 17:50, Nícolas F. R. A. Prado wrote: > > On Mon, Jun 20, 2022 at 10:50:57AM +0200, Krzysztof Kozlowski > > wrote: > > > On 20/06/2022 08:59, Chunfeng Yun wrote: > > > > On Sun, 2022-06-19 at 14:05 +0200, Krzysztof Kozlowski wrote: > > > > > On 19/06/2022 09:46, Chunfeng Yun wrote: > > > > > > On Fri, 2022-06-17 at 18:25 -0700, Krzysztof Kozlowski > > > > > > wrote: > > > > > > > On 17/06/2022 15:29, Nícolas F. R. A. Prado wrote: > > > > > > > > The current clock list in the binding doesn't allow for > > > > > > > > one of > > > > > > > > the > > > > > > > > optional clocks to be missing and a subsequent clock to > > > > > > > > be > > > > > > > > present. > > > > > > > > An > > > > > > > > example where this is an issue is in mt8192.dtsi, which > > > > > > > > has > > > > > > > > "sys_ck", > > > > > > > > "ref_ck", "xhci_ck" and would cause dtbs_check > > > > > > > > warnings. > > > > > > > > > > > > > > > > Change the clock list in a way that allows the middle > > > > > > > > optional > > > > > > > > clocks to > > > > > > > > be missing, while still guaranteeing a fixed order. The > > > > > > > > "ref_ck" is > > > > > > > > kept > > > > > > > > as a const even though it is optional for simplicity, > > > > > > > > since it > > > > > > > > is > > > > > > > > present in all current dts files. > > > > > > > > > > > > > > > > Signed-off-by: Nícolas F. R. A. Prado < > > > > > > > > nfraprado@collabora.com> > > > > > > > > --- > > > > > > > > > > > > > > > > .../devicetree/bindings/usb/mediatek,mtk- > > > > > > > > xhci.yaml | 9 > > > > > > > > +++++++-- > > > > > > > > 1 file changed, 7 insertions(+), 2 deletions(-) > > > > > > > > > > > > > > > > diff --git > > > > > > > > a/Documentation/devicetree/bindings/usb/mediatek,mtk- > > > > > > > > xhci.yaml > > > > > > > > b/Documentation/devicetree/bindings/usb/mediatek,mtk- > > > > > > > > xhci.yaml > > > > > > > > index 63cbc2b62d18..99a1b233ec90 100644 > > > > > > > > --- > > > > > > > > a/Documentation/devicetree/bindings/usb/mediatek,mtk- > > > > > > > > xhci.yaml > > > > > > > > +++ > > > > > > > > b/Documentation/devicetree/bindings/usb/mediatek,mtk- > > > > > > > > xhci.yaml > > > > > > > > @@ -80,8 +80,13 @@ properties: > > > > > > > > items: > > > > > > > > - const: sys_ck # required, the following ones > > > > > > > > are > > > > > > > > optional > > > > > > > > - const: ref_ck > > > > > > > > - - const: mcu_ck > > > > > > > > - - const: dma_ck > > > > > > > > + - enum: > > > > > > > > + - mcu_ck > > > > > > > > + - dma_ck > > > > > > > > + - xhci_ck > > > > > > > > + - enum: > > > > > > > > + - dma_ck > > > > > > > > + - xhci_ck > > > > > > > > - const: xhci_ck > > > > > > > > > > > > > > You allow now almost any order here, including incorrect > > > > > > > like > > > > > > > sys,ref,xhci,xhci,xhci. > > > > > > > > > > > > > > The order of clocks has to be fixed and we cannot allow > > > > > > > flexibility. > > > > > > > Are > > > > > > > you sure that these clocks are actually optional (not > > > > > > > wired to > > > > > > > the > > > > > > > device)? > > > > > > > > > > > > In fact, these optional clocks are fixed, due to no gates > > > > > > are > > > > > > provided, > > > > > > SW can't control them by CCF; > > > > > > In this case, I usually use a fixed clock, or ignore it. > > > > > > > > > > But in some versions these clocks are controllable or not? > > > > > > > > Some SoCs are controllable, some ones are not (fixed clock). > > > > > > Thanks for confirming. Then I would prefer to make these clocks > > > required > > > (not optional) and always provide them - via common clock > > > framework or > > > fixed-clock. > > > > Hi Krzysztof and Chunfeng, > > > > thank you both for the feedback. > > > > Since the solution I proposed in this patch is not acceptable I see > > two options: > > 1. Split the clocks in several if blocks matched by compatibles > > 2. Make the clocks required and use fixed-clock nodes for the > > missing clocks in > > the DT > > > > My understanding is that 1 is the desirable solution if the clock > > is really > > missing in some hardware variants, while 2 is desirable if all > > hardware variants > > really receive all the clocks, only that on some variants they're > > fixed and not > > controlable by SW. > > > > From what I'm reading of this discussion it seems that the latter > > is the case > > here and thus we should go for 2. Is this correct? > > This is how I understood it as well, so correct from my side. Also right for me. > > > > > Also Chunfeng, do you have information on whether the same is true > > for the MMC > > HW block? I recently submitted some changes to that binding [1] but > > I followed > > approach 1 there instead. However if all the clocks are present in > > the HW level > > there as well it would make more sense for me to change it to > > follow approach 2. I discussed it with Wenbin, MMC seems a little different with USB, Hi Wenbin, Please give some comments about MMC, thanks > > > > Thanks, > > Nícolas > > > > [1] > > https://lore.kernel.org/all/20220617230114.2438875-1-nfraprado@collabora.com > > > Best regards, > Krzysztof
On Wed, 2022-06-22 at 09:57 +0800, Chunfeng Yun wrote: > On Tue, 2022-06-21 at 09:14 +0200, Krzysztof Kozlowski wrote: > > On 20/06/2022 17:50, Nícolas F. R. A. Prado wrote: > > > On Mon, Jun 20, 2022 at 10:50:57AM +0200, Krzysztof Kozlowski > > > wrote: > > > > On 20/06/2022 08:59, Chunfeng Yun wrote: > > > > > On Sun, 2022-06-19 at 14:05 +0200, Krzysztof Kozlowski wrote: > > > > > > On 19/06/2022 09:46, Chunfeng Yun wrote: > > > > > > > On Fri, 2022-06-17 at 18:25 -0700, Krzysztof Kozlowski > > > > > > > wrote: > > > > > > > > On 17/06/2022 15:29, Nícolas F. R. A. Prado wrote: > > > > > > > > > The current clock list in the binding doesn't allow > > > > > > > > > for > > > > > > > > > one of > > > > > > > > > the > > > > > > > > > optional clocks to be missing and a subsequent clock > > > > > > > > > to > > > > > > > > > be > > > > > > > > > present. > > > > > > > > > An > > > > > > > > > example where this is an issue is in mt8192.dtsi, > > > > > > > > > which > > > > > > > > > has > > > > > > > > > "sys_ck", > > > > > > > > > "ref_ck", "xhci_ck" and would cause dtbs_check > > > > > > > > > warnings. > > > > > > > > > > > > > > > > > > Change the clock list in a way that allows the middle > > > > > > > > > optional > > > > > > > > > clocks to > > > > > > > > > be missing, while still guaranteeing a fixed order. > > > > > > > > > The > > > > > > > > > "ref_ck" is > > > > > > > > > kept > > > > > > > > > as a const even though it is optional for simplicity, > > > > > > > > > since it > > > > > > > > > is > > > > > > > > > present in all current dts files. > > > > > > > > > > > > > > > > > > Signed-off-by: Nícolas F. R. A. Prado < > > > > > > > > > nfraprado@collabora.com> > > > > > > > > > --- > > > > > > > > > > > > > > > > > > .../devicetree/bindings/usb/mediatek,mtk- > > > > > > > > > xhci.yaml | 9 > > > > > > > > > +++++++-- > > > > > > > > > 1 file changed, 7 insertions(+), 2 deletions(-) > > > > > > > > > > > > > > > > > > diff --git > > > > > > > > > a/Documentation/devicetree/bindings/usb/mediatek,mtk- > > > > > > > > > xhci.yaml > > > > > > > > > b/Documentation/devicetree/bindings/usb/mediatek,mtk- > > > > > > > > > xhci.yaml > > > > > > > > > index 63cbc2b62d18..99a1b233ec90 100644 > > > > > > > > > --- > > > > > > > > > a/Documentation/devicetree/bindings/usb/mediatek,mtk- > > > > > > > > > xhci.yaml > > > > > > > > > +++ > > > > > > > > > b/Documentation/devicetree/bindings/usb/mediatek,mtk- > > > > > > > > > xhci.yaml > > > > > > > > > @@ -80,8 +80,13 @@ properties: > > > > > > > > > items: > > > > > > > > > - const: sys_ck # required, the following > > > > > > > > > ones > > > > > > > > > are > > > > > > > > > optional > > > > > > > > > - const: ref_ck > > > > > > > > > - - const: mcu_ck > > > > > > > > > - - const: dma_ck > > > > > > > > > + - enum: > > > > > > > > > + - mcu_ck > > > > > > > > > + - dma_ck > > > > > > > > > + - xhci_ck > > > > > > > > > + - enum: > > > > > > > > > + - dma_ck > > > > > > > > > + - xhci_ck > > > > > > > > > - const: xhci_ck > > > > > > > > > > > > > > > > You allow now almost any order here, including > > > > > > > > incorrect > > > > > > > > like > > > > > > > > sys,ref,xhci,xhci,xhci. > > > > > > > > > > > > > > > > The order of clocks has to be fixed and we cannot allow > > > > > > > > flexibility. > > > > > > > > Are > > > > > > > > you sure that these clocks are actually optional (not > > > > > > > > wired to > > > > > > > > the > > > > > > > > device)? > > > > > > > > > > > > > > In fact, these optional clocks are fixed, due to no gates > > > > > > > are > > > > > > > provided, > > > > > > > SW can't control them by CCF; > > > > > > > In this case, I usually use a fixed clock, or ignore it. > > > > > > > > > > > > But in some versions these clocks are controllable or not? > > > > > > > > > > Some SoCs are controllable, some ones are not (fixed clock). > > > > > > > > Thanks for confirming. Then I would prefer to make these clocks > > > > required > > > > (not optional) and always provide them - via common clock > > > > framework or > > > > fixed-clock. > > > > > > Hi Krzysztof and Chunfeng, > > > > > > thank you both for the feedback. > > > > > > Since the solution I proposed in this patch is not acceptable I > > > see > > > two options: > > > 1. Split the clocks in several if blocks matched by compatibles > > > 2. Make the clocks required and use fixed-clock nodes for the > > > missing clocks in > > > the DT > > > > > > My understanding is that 1 is the desirable solution if the clock > > > is really > > > missing in some hardware variants, while 2 is desirable if all > > > hardware variants > > > really receive all the clocks, only that on some variants they're > > > fixed and not > > > controlable by SW. > > > > > > From what I'm reading of this discussion it seems that the latter > > > is the case > > > here and thus we should go for 2. Is this correct? > > > > This is how I understood it as well, so correct from my side. > > Also right for me. > > > > > > > > > Also Chunfeng, do you have information on whether the same is > > > true > > > for the MMC > > > HW block? I recently submitted some changes to that binding [1] > > > but > > > I followed > > > approach 1 there instead. However if all the clocks are present > > > in > > > the HW level > > > there as well it would make more sense for me to change it to > > > follow approach 2. > > I discussed it with Wenbin, MMC seems a little different with USB, > > Hi Wenbin, > > Please give some comments about MMC, thanks > Hi Chunfeng, As we discussed, the following change is the desirable solution for the Mediatek MMC HW. https://lists.infradead.org/pipermail/linux-mediatek/2022-June/043691.html Thanks. > > > > > > Thanks, > > > Nícolas > > > > > > [1] > > > https://lore.kernel.org/all/20220617230114.2438875-1-nfraprado@collabora.com > > > > > > Best regards, > > Krzysztof > >
On Wed, Jun 22, 2022 at 02:10:55PM +0800, Wenbin Mei wrote: > On Wed, 2022-06-22 at 09:57 +0800, Chunfeng Yun wrote: > > On Tue, 2022-06-21 at 09:14 +0200, Krzysztof Kozlowski wrote: > > > On 20/06/2022 17:50, Nícolas F. R. A. Prado wrote: > > > > On Mon, Jun 20, 2022 at 10:50:57AM +0200, Krzysztof Kozlowski > > > > wrote: > > > > > On 20/06/2022 08:59, Chunfeng Yun wrote: > > > > > > On Sun, 2022-06-19 at 14:05 +0200, Krzysztof Kozlowski wrote: > > > > > > > On 19/06/2022 09:46, Chunfeng Yun wrote: > > > > > > > > On Fri, 2022-06-17 at 18:25 -0700, Krzysztof Kozlowski > > > > > > > > wrote: > > > > > > > > > On 17/06/2022 15:29, Nícolas F. R. A. Prado wrote: > > > > > > > > > > The current clock list in the binding doesn't allow > > > > > > > > > > for > > > > > > > > > > one of > > > > > > > > > > the > > > > > > > > > > optional clocks to be missing and a subsequent clock > > > > > > > > > > to > > > > > > > > > > be > > > > > > > > > > present. > > > > > > > > > > An > > > > > > > > > > example where this is an issue is in mt8192.dtsi, > > > > > > > > > > which > > > > > > > > > > has > > > > > > > > > > "sys_ck", > > > > > > > > > > "ref_ck", "xhci_ck" and would cause dtbs_check > > > > > > > > > > warnings. > > > > > > > > > > > > > > > > > > > > Change the clock list in a way that allows the middle > > > > > > > > > > optional > > > > > > > > > > clocks to > > > > > > > > > > be missing, while still guaranteeing a fixed order. > > > > > > > > > > The > > > > > > > > > > "ref_ck" is > > > > > > > > > > kept > > > > > > > > > > as a const even though it is optional for simplicity, > > > > > > > > > > since it > > > > > > > > > > is > > > > > > > > > > present in all current dts files. > > > > > > > > > > > > > > > > > > > > Signed-off-by: Nícolas F. R. A. Prado < > > > > > > > > > > nfraprado@collabora.com> > > > > > > > > > > --- > > > > > > > > > > > > > > > > > > > > .../devicetree/bindings/usb/mediatek,mtk- > > > > > > > > > > xhci.yaml | 9 > > > > > > > > > > +++++++-- > > > > > > > > > > 1 file changed, 7 insertions(+), 2 deletions(-) > > > > > > > > > > > > > > > > > > > > diff --git > > > > > > > > > > a/Documentation/devicetree/bindings/usb/mediatek,mtk- > > > > > > > > > > xhci.yaml > > > > > > > > > > b/Documentation/devicetree/bindings/usb/mediatek,mtk- > > > > > > > > > > xhci.yaml > > > > > > > > > > index 63cbc2b62d18..99a1b233ec90 100644 > > > > > > > > > > --- > > > > > > > > > > a/Documentation/devicetree/bindings/usb/mediatek,mtk- > > > > > > > > > > xhci.yaml > > > > > > > > > > +++ > > > > > > > > > > b/Documentation/devicetree/bindings/usb/mediatek,mtk- > > > > > > > > > > xhci.yaml > > > > > > > > > > @@ -80,8 +80,13 @@ properties: > > > > > > > > > > items: > > > > > > > > > > - const: sys_ck # required, the following > > > > > > > > > > ones > > > > > > > > > > are > > > > > > > > > > optional > > > > > > > > > > - const: ref_ck > > > > > > > > > > - - const: mcu_ck > > > > > > > > > > - - const: dma_ck > > > > > > > > > > + - enum: > > > > > > > > > > + - mcu_ck > > > > > > > > > > + - dma_ck > > > > > > > > > > + - xhci_ck > > > > > > > > > > + - enum: > > > > > > > > > > + - dma_ck > > > > > > > > > > + - xhci_ck > > > > > > > > > > - const: xhci_ck > > > > > > > > > > > > > > > > > > You allow now almost any order here, including > > > > > > > > > incorrect > > > > > > > > > like > > > > > > > > > sys,ref,xhci,xhci,xhci. > > > > > > > > > > > > > > > > > > The order of clocks has to be fixed and we cannot allow > > > > > > > > > flexibility. > > > > > > > > > Are > > > > > > > > > you sure that these clocks are actually optional (not > > > > > > > > > wired to > > > > > > > > > the > > > > > > > > > device)? > > > > > > > > > > > > > > > > In fact, these optional clocks are fixed, due to no gates > > > > > > > > are > > > > > > > > provided, > > > > > > > > SW can't control them by CCF; > > > > > > > > In this case, I usually use a fixed clock, or ignore it. > > > > > > > > > > > > > > But in some versions these clocks are controllable or not? > > > > > > > > > > > > Some SoCs are controllable, some ones are not (fixed clock). > > > > > > > > > > Thanks for confirming. Then I would prefer to make these clocks > > > > > required > > > > > (not optional) and always provide them - via common clock > > > > > framework or > > > > > fixed-clock. > > > > > > > > Hi Krzysztof and Chunfeng, > > > > > > > > thank you both for the feedback. > > > > > > > > Since the solution I proposed in this patch is not acceptable I > > > > see > > > > two options: > > > > 1. Split the clocks in several if blocks matched by compatibles > > > > 2. Make the clocks required and use fixed-clock nodes for the > > > > missing clocks in > > > > the DT > > > > > > > > My understanding is that 1 is the desirable solution if the clock > > > > is really > > > > missing in some hardware variants, while 2 is desirable if all > > > > hardware variants > > > > really receive all the clocks, only that on some variants they're > > > > fixed and not > > > > controlable by SW. > > > > > > > > From what I'm reading of this discussion it seems that the latter > > > > is the case > > > > here and thus we should go for 2. Is this correct? > > > > > > This is how I understood it as well, so correct from my side. > > > > Also right for me. > > > > > > > > > > > > > Also Chunfeng, do you have information on whether the same is > > > > true > > > > for the MMC > > > > HW block? I recently submitted some changes to that binding [1] > > > > but > > > > I followed > > > > approach 1 there instead. However if all the clocks are present > > > > in > > > > the HW level > > > > there as well it would make more sense for me to change it to > > > > follow approach 2. > > > > I discussed it with Wenbin, MMC seems a little different with USB, > > > > Hi Wenbin, > > > > Please give some comments about MMC, thanks > > > Hi Chunfeng, > > As we discussed, the following change is the desirable solution for the > Mediatek MMC HW. > > https://lists.infradead.org/pipermail/linux-mediatek/2022-June/043691.html Got it, thank you both. I'll keep that approach for MMC then, and change the one here for USB. Thanks, Nícolas
diff --git a/Documentation/devicetree/bindings/usb/mediatek,mtk-xhci.yaml b/Documentation/devicetree/bindings/usb/mediatek,mtk-xhci.yaml index 63cbc2b62d18..99a1b233ec90 100644 --- a/Documentation/devicetree/bindings/usb/mediatek,mtk-xhci.yaml +++ b/Documentation/devicetree/bindings/usb/mediatek,mtk-xhci.yaml @@ -80,8 +80,13 @@ properties: items: - const: sys_ck # required, the following ones are optional - const: ref_ck - - const: mcu_ck - - const: dma_ck + - enum: + - mcu_ck + - dma_ck + - xhci_ck + - enum: + - dma_ck + - xhci_ck - const: xhci_ck assigned-clocks:
The current clock list in the binding doesn't allow for one of the optional clocks to be missing and a subsequent clock to be present. An example where this is an issue is in mt8192.dtsi, which has "sys_ck", "ref_ck", "xhci_ck" and would cause dtbs_check warnings. Change the clock list in a way that allows the middle optional clocks to be missing, while still guaranteeing a fixed order. The "ref_ck" is kept as a const even though it is optional for simplicity, since it is present in all current dts files. Signed-off-by: Nícolas F. R. A. Prado <nfraprado@collabora.com> --- .../devicetree/bindings/usb/mediatek,mtk-xhci.yaml | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-)