[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <1455588568.19396.51.camel@mtksdaap41>
Date: Tue, 16 Feb 2016 10:09:28 +0800
From: tiffany lin <tiffany.lin@...iatek.com>
To: Daniel Kurtz <djkurtz@...omium.org>
CC: Hans Verkuil <hans.verkuil@...co.com>,
Daniel Thompson <daniel.thompson@...aro.org>,
Rob Herring <robh+dt@...nel.org>,
"Mauro Carvalho Chehab" <mchehab@....samsung.com>,
Matthias Brugger <matthias.bgg@...il.com>,
Pawel Osciak <posciak@...omium.org>,
Eddie Huang <eddie.huang@...iatek.com>,
Yingjoe Chen <yingjoe.chen@...iatek.com>,
"open list:OPEN FIRMWARE AND..." <devicetree@...r.kernel.org>,
"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
"linux-arm-kernel@...ts.infradead.org"
<linux-arm-kernel@...ts.infradead.org>,
<linux-media@...r.kernel.org>,
"moderated list:ARM/Mediatek SoC support"
<linux-mediatek@...ts.infradead.org>,
Lin PoChun <PoChun.Lin@...iatek.com>,
Tomasz Figa <tfiga@...omium.org>
Subject: Re: [PATCH v4 4/8] dt-bindings: Add a binding for Mediatek Video
Encoder
Hi Daniel,
On Mon, 2016-02-15 at 18:42 +0800, Daniel Kurtz wrote:
> On Tue, Feb 9, 2016 at 7:29 PM, Daniel Kurtz <djkurtz@...omium.org> wrote:
> > Hi Tiffany,
> >
> > On Thu, Feb 4, 2016 at 7:34 PM, Tiffany Lin <tiffany.lin@...iatek.com> wrote:
> >> Add a DT binding documentation of Video Encoder for the
> >> MT8173 SoC from Mediatek.
> >>
> >> Signed-off-by: Tiffany Lin <tiffany.lin@...iatek.com>
> >> ---
> >> .../devicetree/bindings/media/mediatek-vcodec.txt | 59 ++++++++++++++++++++
> >> 1 file changed, 59 insertions(+)
> >> create mode 100644 Documentation/devicetree/bindings/media/mediatek-vcodec.txt
> >>
> >> diff --git a/Documentation/devicetree/bindings/media/mediatek-vcodec.txt b/Documentation/devicetree/bindings/media/mediatek-vcodec.txt
> >> new file mode 100644
> >> index 0000000..572bfdd
> >> --- /dev/null
> >> +++ b/Documentation/devicetree/bindings/media/mediatek-vcodec.txt
> >> @@ -0,0 +1,59 @@
> >> +Mediatek Video Codec
> >> +
> >> +Mediatek Video Codec is the video codec hw present in Mediatek SoCs which
> >> +supports high resolution encoding functionalities.
> >> +
> >> +Required properties:
> >> +- compatible : "mediatek,mt8173-vcodec-enc" for encoder
> >> +- reg : Physical base address of the video codec registers and length of
> >> + memory mapped region.
> >> +- interrupts : interrupt number to the cpu.
> >> +- mediatek,larb : must contain the local arbiters in the current Socs.
> >> +- clocks : list of clock specifiers, corresponding to entries in
> >> + the clock-names property.
> >> +- clock-names: encoder must contain "vencpll_d2", "venc_sel", "univpll1_d2",
> >> + "venc_lt_sel".
> >> +- iommus : should point to the respective IOMMU block with master port as
> >> + argument, see Documentation/devicetree/bindings/iommu/mediatek,iommu.txt
> >> + for details.
> >> +- mediatek,vpu : the node of video processor unit
> >> +
> >> +Example:
> >> +vcodec_enc: vcodec@...8002000 {
> >> + compatible = "mediatek,mt8173-vcodec-enc";
> >> + reg = <0 0x18002000 0 0x1000>, /*VENC_SYS*/
> >> + <0 0x19002000 0 0x1000>; /*VENC_LT_SYS*/
> >
> > This really looks like two encoder devices combined into a single
> > device tree node.
> > There are two register sets, two irqs, two sets of iommus, and two
> > sets of clocks.
> >
> > If possible, please split this node into two, one for each encoder.
>
> I chatted offline with Mediatek. They explained that there really is
> just one encoder hardware, that happens to support multiple formats.
> The encoder cannot encode with both formats at the same time. The
> Mediatek HW designers added a new format to an existing encoder by
> adding a second interface (register set, irq, iommus, clocks) without
> modifying the original interface. However in the hardware itself
> there is really just one encoder device.
>
> So, although this node looks like it is for two encoder devices (one
> for each format), really there is just one device that supports each
> format through its large interface.
>
> So, I'm fine with this being a single device node.
>
> >> + interrupts = <GIC_SPI 198 IRQ_TYPE_LEVEL_LOW>,
> >> + <GIC_SPI 202 IRQ_TYPE_LEVEL_LOW>;
> >> + mediatek,larb = <&larb3>,
> >> + <&larb5>;
> >> + iommus = <&iommu M4U_PORT_VENC_RCPU>,
> >> + <&iommu M4U_PORT_VENC_REC>,
> >> + <&iommu M4U_PORT_VENC_BSDMA>,
> >> + <&iommu M4U_PORT_VENC_SV_COMV>,
> >> + <&iommu M4U_PORT_VENC_RD_COMV>,
> >> + <&iommu M4U_PORT_VENC_CUR_LUMA>,
> >> + <&iommu M4U_PORT_VENC_CUR_CHROMA>,
> >> + <&iommu M4U_PORT_VENC_REF_LUMA>,
> >> + <&iommu M4U_PORT_VENC_REF_CHROMA>,
> >> + <&iommu M4U_PORT_VENC_NBM_RDMA>,
> >> + <&iommu M4U_PORT_VENC_NBM_WDMA>,
> >> + <&iommu M4U_PORT_VENC_RCPU_SET2>,
> >> + <&iommu M4U_PORT_VENC_REC_FRM_SET2>,
> >> + <&iommu M4U_PORT_VENC_BSDMA_SET2>,
> >> + <&iommu M4U_PORT_VENC_SV_COMA_SET2>,
> >> + <&iommu M4U_PORT_VENC_RD_COMA_SET2>,
> >> + <&iommu M4U_PORT_VENC_CUR_LUMA_SET2>,
> >> + <&iommu M4U_PORT_VENC_CUR_CHROMA_SET2>,
> >> + <&iommu M4U_PORT_VENC_REF_LUMA_SET2>,
> >> + <&iommu M4U_PORT_VENC_REC_CHROMA_SET2>;
> >> + mediatek,vpu = <&vpu>;
> >> + clocks = <&topckgen CLK_TOP_VENCPLL_D2>,
> >> + <&topckgen CLK_TOP_VENC_SEL>,
> >> + <&topckgen CLK_TOP_UNIVPLL1_D2>,
> >> + <&topckgen CLK_TOP_VENC_LT_SEL>;
> >> + clock-names = "vencpll_d2",
> >> + "venc_sel",
> >> + "univpll1_d2",
> >> + "venc_lt_sel";
> >
> > The names of these clocks should be from the perspective of the
> > encoder, not the clock provider.
>
> I still think these clock names should be updated, however.
>
Got it. We will fix this in next version.
> -Dan
Powered by blists - more mailing lists