| Message ID | 1534843809-4137-2-git-send-email-yamada.masahiro@socionext.com (mailing list archive) |
|---|---|
| State | Changes Requested |
| Headers | show |
| Series | dmaengine: add UniPhier MIO DMAC driver | expand |
(+CC Rob, DT, LKML) I forgot to CC this to DT community... 2018-08-21 18:30 GMT+09:00 Masahiro Yamada <yamada.masahiro@socionext.com>: > The MIO DMAC (Media IO DMA Controller) is used in UniPhier LD4, > Pro4, and sLD8 SoCs. > > Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> > --- > > .../devicetree/bindings/dma/uniphier-mio-dmac.txt | 28 ++++++++++++++++++++++ > 1 file changed, 28 insertions(+) > create mode 100644 Documentation/devicetree/bindings/dma/uniphier-mio-dmac.txt > > diff --git a/Documentation/devicetree/bindings/dma/uniphier-mio-dmac.txt b/Documentation/devicetree/bindings/dma/uniphier-mio-dmac.txt > new file mode 100644 > index 0000000..a9e969e > --- /dev/null > +++ b/Documentation/devicetree/bindings/dma/uniphier-mio-dmac.txt > @@ -0,0 +1,28 @@ > +UniPhier Media IO DMA controller > + > +This works as an external DMA engine for SD/eMMC controllers etc. > +found in UniPhier LD4, Pro4, sLD8 SoCs. > + > +Required properties: > +- compatible: should be "socionext,uniphier-mio-dmac". > +- reg: offset and length of the register set for the device. > +- interrupts: a list of interrupt specifiers associated with the DMA channels. > +- clocks: a single clock specifier > +- #dma-cells: should be <1>. The single cell represents the channel number. > +- dma-channels: specify the number of the DMA channels. This should match to > + the number of tuples in the interrupts property. > + > +Example: > + dmac: dmac@5a000000 { > + compatible = "socionext,uniphier-mio-dmac"; > + reg = <0x5a000000 0x1000>; > + interrupts = <0 68 4>, <0 68 4>, <0 69 4>, <0 70 4>, > + <0 71 4>, <0 72 4>, <0 73 4>, <0 74 4>; > + clocks = <&mio_clk 7>; > + #dma-cells = <1>; > + dma-channels = <8>; > + }; > + > +Note: > +In the example above, "interrupts = <0 68 4>, <0 68 4>, ..." is not a typo. > +The first two channels share a single interrupt line. > -- > 2.7.4 >
On 21 August 2018 at 15:17, Masahiro Yamada <yamada.masahiro@socionext.com> wrote: > (+CC Rob, DT, LKML) > > I forgot to CC this to DT community... > > > 2018-08-21 18:30 GMT+09:00 Masahiro Yamada <yamada.masahiro@socionext.com>: >> The MIO DMAC (Media IO DMA Controller) is used in UniPhier LD4, >> Pro4, and sLD8 SoCs. >> >> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> >> --- >> >> .../devicetree/bindings/dma/uniphier-mio-dmac.txt | 28 ++++++++++++++++++++++ >> 1 file changed, 28 insertions(+) >> create mode 100644 Documentation/devicetree/bindings/dma/uniphier-mio-dmac.txt >> >> diff --git a/Documentation/devicetree/bindings/dma/uniphier-mio-dmac.txt b/Documentation/devicetree/bindings/dma/uniphier-mio-dmac.txt >> new file mode 100644 >> index 0000000..a9e969e >> --- /dev/null >> +++ b/Documentation/devicetree/bindings/dma/uniphier-mio-dmac.txt >> @@ -0,0 +1,28 @@ >> +UniPhier Media IO DMA controller >> + >> +This works as an external DMA engine for SD/eMMC controllers etc. >> +found in UniPhier LD4, Pro4, sLD8 SoCs. >> + >> +Required properties: >> +- compatible: should be "socionext,uniphier-mio-dmac". >> +- reg: offset and length of the register set for the device. >> +- interrupts: a list of interrupt specifiers associated with the DMA channels. >> +- clocks: a single clock specifier >> +- #dma-cells: should be <1>. The single cell represents the channel number. >> +- dma-channels: specify the number of the DMA channels. This should match to >> + the number of tuples in the interrupts property. >> + Can we not infer the number of channels from interrupt tuples? After all the driver assumes they are same.
On Tue, Aug 21, 2018 at 4:48 AM Masahiro Yamada <yamada.masahiro@socionext.com> wrote: > > (+CC Rob, DT, LKML) > > I forgot to CC this to DT community... You really need to resend so that patchwork will pick it up and I'll see it for sure. > > > 2018-08-21 18:30 GMT+09:00 Masahiro Yamada <yamada.masahiro@socionext.com>: > > The MIO DMAC (Media IO DMA Controller) is used in UniPhier LD4, > > Pro4, and sLD8 SoCs. > > > > Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> > > --- > > > > .../devicetree/bindings/dma/uniphier-mio-dmac.txt | 28 ++++++++++++++++++++++ > > 1 file changed, 28 insertions(+) > > create mode 100644 Documentation/devicetree/bindings/dma/uniphier-mio-dmac.txt > > > > diff --git a/Documentation/devicetree/bindings/dma/uniphier-mio-dmac.txt b/Documentation/devicetree/bindings/dma/uniphier-mio-dmac.txt > > new file mode 100644 > > index 0000000..a9e969e > > --- /dev/null > > +++ b/Documentation/devicetree/bindings/dma/uniphier-mio-dmac.txt > > @@ -0,0 +1,28 @@ > > +UniPhier Media IO DMA controller > > + > > +This works as an external DMA engine for SD/eMMC controllers etc. > > +found in UniPhier LD4, Pro4, sLD8 SoCs. > > + > > +Required properties: > > +- compatible: should be "socionext,uniphier-mio-dmac". > > +- reg: offset and length of the register set for the device. > > +- interrupts: a list of interrupt specifiers associated with the DMA channels. > > +- clocks: a single clock specifier > > +- #dma-cells: should be <1>. The single cell represents the channel number. > > +- dma-channels: specify the number of the DMA channels. This should match to > > + the number of tuples in the interrupts property. > > + > > +Example: > > + dmac: dmac@5a000000 { dma-controller@... > > + compatible = "socionext,uniphier-mio-dmac"; > > + reg = <0x5a000000 0x1000>; > > + interrupts = <0 68 4>, <0 68 4>, <0 69 4>, <0 70 4>, > > + <0 71 4>, <0 72 4>, <0 73 4>, <0 74 4>; > > + clocks = <&mio_clk 7>; > > + #dma-cells = <1>; > > + dma-channels = <8>; > > + }; > > + > > +Note: > > +In the example above, "interrupts = <0 68 4>, <0 68 4>, ..." is not a typo. > > +The first two channels share a single interrupt line. > > -- > > 2.7.4 > > > > > > -- > Best Regards > Masahiro Yamada
Hi Jassi, 2018-08-21 19:44 GMT+09:00 Jassi Brar <jaswinder.singh@linaro.org>: > On 21 August 2018 at 15:17, Masahiro Yamada > <yamada.masahiro@socionext.com> wrote: >> (+CC Rob, DT, LKML) >> >> I forgot to CC this to DT community... >> >> >> 2018-08-21 18:30 GMT+09:00 Masahiro Yamada <yamada.masahiro@socionext.com>: >>> The MIO DMAC (Media IO DMA Controller) is used in UniPhier LD4, >>> Pro4, and sLD8 SoCs. >>> >>> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> >>> --- >>> >>> .../devicetree/bindings/dma/uniphier-mio-dmac.txt | 28 ++++++++++++++++++++++ >>> 1 file changed, 28 insertions(+) >>> create mode 100644 Documentation/devicetree/bindings/dma/uniphier-mio-dmac.txt >>> >>> diff --git a/Documentation/devicetree/bindings/dma/uniphier-mio-dmac.txt b/Documentation/devicetree/bindings/dma/uniphier-mio-dmac.txt >>> new file mode 100644 >>> index 0000000..a9e969e >>> --- /dev/null >>> +++ b/Documentation/devicetree/bindings/dma/uniphier-mio-dmac.txt >>> @@ -0,0 +1,28 @@ >>> +UniPhier Media IO DMA controller >>> + >>> +This works as an external DMA engine for SD/eMMC controllers etc. >>> +found in UniPhier LD4, Pro4, sLD8 SoCs. >>> + >>> +Required properties: >>> +- compatible: should be "socionext,uniphier-mio-dmac". >>> +- reg: offset and length of the register set for the device. >>> +- interrupts: a list of interrupt specifiers associated with the DMA channels. >>> +- clocks: a single clock specifier >>> +- #dma-cells: should be <1>. The single cell represents the channel number. >>> +- dma-channels: specify the number of the DMA channels. This should match to >>> + the number of tuples in the interrupts property. >>> + > Can we not infer the number of channels from interrupt tuples? After > all the driver assumes they are same. It would be possible to count the number of tuples in "interrupts". I know of_irq_count(), but I do not see any driver in drivers/dma/ that calls it. I guess the reason is that of_irq_count() is not exported, so tristate drivers like this cannot use it. I checked Documentation/devicetree/bindings/dma/, and some controllers specify _redundant_ dma-channels property. fsl-mxs-dma.txt renesas,rcar-dmac.txt renesas,usb-dmac.txt I also see counter-implementation. bcm2835-dma.c hard-codes the number of channels in the driver. tegra210-adma.c associates nr_channels with compatible string. I will wait for comments from the maintainers. If desired, I will export of_irq_count() and use it from my driver. Thanks.
On 23 August 2018 at 10:48, Masahiro Yamada <yamada.masahiro@socionext.com> wrote: > Hi Jassi, > > > 2018-08-21 19:44 GMT+09:00 Jassi Brar <jaswinder.singh@linaro.org>: >> On 21 August 2018 at 15:17, Masahiro Yamada >> <yamada.masahiro@socionext.com> wrote: >>> (+CC Rob, DT, LKML) >>> >>> I forgot to CC this to DT community... >>> >>> >>> 2018-08-21 18:30 GMT+09:00 Masahiro Yamada <yamada.masahiro@socionext.com>: >>>> The MIO DMAC (Media IO DMA Controller) is used in UniPhier LD4, >>>> Pro4, and sLD8 SoCs. >>>> >>>> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> >>>> --- >>>> >>>> .../devicetree/bindings/dma/uniphier-mio-dmac.txt | 28 ++++++++++++++++++++++ >>>> 1 file changed, 28 insertions(+) >>>> create mode 100644 Documentation/devicetree/bindings/dma/uniphier-mio-dmac.txt >>>> >>>> diff --git a/Documentation/devicetree/bindings/dma/uniphier-mio-dmac.txt b/Documentation/devicetree/bindings/dma/uniphier-mio-dmac.txt >>>> new file mode 100644 >>>> index 0000000..a9e969e >>>> --- /dev/null >>>> +++ b/Documentation/devicetree/bindings/dma/uniphier-mio-dmac.txt >>>> @@ -0,0 +1,28 @@ >>>> +UniPhier Media IO DMA controller >>>> + >>>> +This works as an external DMA engine for SD/eMMC controllers etc. >>>> +found in UniPhier LD4, Pro4, sLD8 SoCs. >>>> + >>>> +Required properties: >>>> +- compatible: should be "socionext,uniphier-mio-dmac". >>>> +- reg: offset and length of the register set for the device. >>>> +- interrupts: a list of interrupt specifiers associated with the DMA channels. >>>> +- clocks: a single clock specifier >>>> +- #dma-cells: should be <1>. The single cell represents the channel number. >>>> +- dma-channels: specify the number of the DMA channels. This should match to >>>> + the number of tuples in the interrupts property. >>>> + >> Can we not infer the number of channels from interrupt tuples? After >> all the driver assumes they are same. > > > It would be possible to count the number of tuples > in "interrupts". > > > > I know of_irq_count(), but I do not see any driver > in drivers/dma/ that calls it. > > > I guess the reason is that of_irq_count() is not exported, > so tristate drivers like this cannot use it. > > > I checked Documentation/devicetree/bindings/dma/, > and some controllers specify _redundant_ dma-channels property. > > fsl-mxs-dma.txt > renesas,rcar-dmac.txt > renesas,usb-dmac.txt > :) I am not sure "because others are doing it" is a good reason to introduce redundancy. > I also see counter-implementation. > > > bcm2835-dma.c hard-codes the number of channels in the driver. > tegra210-adma.c associates nr_channels with compatible string. > > > > I will wait for comments from the maintainers. > > If desired, I will export of_irq_count() > and use it from my driver. > If you don't want to leave too much footprint, you could do count = 0; while (of_irq_parse_one(dev, count, &irq) == 0) count++ of_irq_parse_one() is already exported. A good side-effect is you wouldn't have to hardcode the count in the driver (like bcm and tegra examples you quote). Having said that, I wouldn't lose sleep over it. So .... Cheers!
On Thu, Aug 23, 2018 at 12:38 AM Jassi Brar <jaswinder.singh@linaro.org> wrote: > > On 23 August 2018 at 10:48, Masahiro Yamada > <yamada.masahiro@socionext.com> wrote: > > Hi Jassi, > > > > > > 2018-08-21 19:44 GMT+09:00 Jassi Brar <jaswinder.singh@linaro.org>: > >> On 21 August 2018 at 15:17, Masahiro Yamada > >> <yamada.masahiro@socionext.com> wrote: > >>> (+CC Rob, DT, LKML) > >>> > >>> I forgot to CC this to DT community... > >>> > >>> > >>> 2018-08-21 18:30 GMT+09:00 Masahiro Yamada <yamada.masahiro@socionext.com>: > >>>> The MIO DMAC (Media IO DMA Controller) is used in UniPhier LD4, > >>>> Pro4, and sLD8 SoCs. > >>>> > >>>> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> > >>>> --- > >>>> > >>>> .../devicetree/bindings/dma/uniphier-mio-dmac.txt | 28 ++++++++++++++++++++++ > >>>> 1 file changed, 28 insertions(+) > >>>> create mode 100644 Documentation/devicetree/bindings/dma/uniphier-mio-dmac.txt > >>>> > >>>> diff --git a/Documentation/devicetree/bindings/dma/uniphier-mio-dmac.txt b/Documentation/devicetree/bindings/dma/uniphier-mio-dmac.txt > >>>> new file mode 100644 > >>>> index 0000000..a9e969e > >>>> --- /dev/null > >>>> +++ b/Documentation/devicetree/bindings/dma/uniphier-mio-dmac.txt > >>>> @@ -0,0 +1,28 @@ > >>>> +UniPhier Media IO DMA controller > >>>> + > >>>> +This works as an external DMA engine for SD/eMMC controllers etc. > >>>> +found in UniPhier LD4, Pro4, sLD8 SoCs. > >>>> + > >>>> +Required properties: > >>>> +- compatible: should be "socionext,uniphier-mio-dmac". > >>>> +- reg: offset and length of the register set for the device. > >>>> +- interrupts: a list of interrupt specifiers associated with the DMA channels. > >>>> +- clocks: a single clock specifier > >>>> +- #dma-cells: should be <1>. The single cell represents the channel number. > >>>> +- dma-channels: specify the number of the DMA channels. This should match to > >>>> + the number of tuples in the interrupts property. > >>>> + > >> Can we not infer the number of channels from interrupt tuples? After > >> all the driver assumes they are same. > > > > > > It would be possible to count the number of tuples > > in "interrupts". > > > > > > > > I know of_irq_count(), but I do not see any driver > > in drivers/dma/ that calls it. > > > > > > I guess the reason is that of_irq_count() is not exported, > > so tristate drivers like this cannot use it. > > > > > > I checked Documentation/devicetree/bindings/dma/, > > and some controllers specify _redundant_ dma-channels property. > > > > fsl-mxs-dma.txt > > renesas,rcar-dmac.txt > > renesas,usb-dmac.txt > > > :) I am not sure "because others are doing it" is a good reason to > introduce redundancy. > > > > I also see counter-implementation. > > > > > > bcm2835-dma.c hard-codes the number of channels in the driver. > > tegra210-adma.c associates nr_channels with compatible string. > > > > > > > > I will wait for comments from the maintainers. > > > > If desired, I will export of_irq_count() > > and use it from my driver. > > > If you don't want to leave too much footprint, you could do > > count = 0; > while (of_irq_parse_one(dev, count, &irq) == 0) count++ > > of_irq_parse_one() is already exported. Yes, but we really don't more users and drivers shouldn't be using it. Grepping DT functions and when the only users are pretty much powerpc, that's a good indication not to use the function. And you don't want to use of_irq_count either. platform_irq_count is what should be used here. It's already exported. Rob
On 23 August 2018 at 18:51, Rob Herring <robh+dt@kernel.org> wrote: > On Thu, Aug 23, 2018 at 12:38 AM Jassi Brar <jaswinder.singh@linaro.org> wrote: >> On 23 August 2018 at 10:48, Masahiro Yamada >> > >> > If desired, I will export of_irq_count() >> > and use it from my driver. >> > >> If you don't want to leave too much footprint, you could do >> >> count = 0; >> while (of_irq_parse_one(dev, count, &irq) == 0) count++ >> >> of_irq_parse_one() is already exported. > > Yes, but we really don't more users and drivers shouldn't be using it. > Grepping DT functions and when the only users are pretty much powerpc, > that's a good indication not to use the function. > > And you don't want to use of_irq_count either. platform_irq_count is > what should be used here. It's already exported. > Thanks, platform_irq_count() is definitely better. Yamada-san, for example, gpio-tegra.c infers the number of banks from platform_irq_count() rather than the 'gpio-banks' property.
Hi Rob, Jassi, 2018-08-23 23:12 GMT+09:00 Jassi Brar <jaswinder.singh@linaro.org>: > On 23 August 2018 at 18:51, Rob Herring <robh+dt@kernel.org> wrote: >> On Thu, Aug 23, 2018 at 12:38 AM Jassi Brar <jaswinder.singh@linaro.org> wrote: >>> On 23 August 2018 at 10:48, Masahiro Yamada > >>> > >>> > If desired, I will export of_irq_count() >>> > and use it from my driver. >>> > >>> If you don't want to leave too much footprint, you could do >>> >>> count = 0; >>> while (of_irq_parse_one(dev, count, &irq) == 0) count++ >>> >>> of_irq_parse_one() is already exported. >> >> Yes, but we really don't more users and drivers shouldn't be using it. >> Grepping DT functions and when the only users are pretty much powerpc, >> that's a good indication not to use the function. >> >> And you don't want to use of_irq_count either. platform_irq_count is >> what should be used here. It's already exported. >> > Thanks, platform_irq_count() is definitely better. > > Yamada-san, for example, gpio-tegra.c infers the number of banks from > platform_irq_count() rather than the 'gpio-banks' property. I did not platform_irq_count(). I will send v2 with it. Thanks.
diff --git a/Documentation/devicetree/bindings/dma/uniphier-mio-dmac.txt b/Documentation/devicetree/bindings/dma/uniphier-mio-dmac.txt new file mode 100644 index 0000000..a9e969e --- /dev/null +++ b/Documentation/devicetree/bindings/dma/uniphier-mio-dmac.txt @@ -0,0 +1,28 @@ +UniPhier Media IO DMA controller + +This works as an external DMA engine for SD/eMMC controllers etc. +found in UniPhier LD4, Pro4, sLD8 SoCs. + +Required properties: +- compatible: should be "socionext,uniphier-mio-dmac". +- reg: offset and length of the register set for the device. +- interrupts: a list of interrupt specifiers associated with the DMA channels. +- clocks: a single clock specifier +- #dma-cells: should be <1>. The single cell represents the channel number. +- dma-channels: specify the number of the DMA channels. This should match to + the number of tuples in the interrupts property. + +Example: + dmac: dmac@5a000000 { + compatible = "socionext,uniphier-mio-dmac"; + reg = <0x5a000000 0x1000>; + interrupts = <0 68 4>, <0 68 4>, <0 69 4>, <0 70 4>, + <0 71 4>, <0 72 4>, <0 73 4>, <0 74 4>; + clocks = <&mio_clk 7>; + #dma-cells = <1>; + dma-channels = <8>; + }; + +Note: +In the example above, "interrupts = <0 68 4>, <0 68 4>, ..." is not a typo. +The first two channels share a single interrupt line.
The MIO DMAC (Media IO DMA Controller) is used in UniPhier LD4, Pro4, and sLD8 SoCs. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> --- .../devicetree/bindings/dma/uniphier-mio-dmac.txt | 28 ++++++++++++++++++++++ 1 file changed, 28 insertions(+) create mode 100644 Documentation/devicetree/bindings/dma/uniphier-mio-dmac.txt