Dear Laurent and Sakari, On Sat, 2019-02-09 at 20:20 +0200, Laurent Pinchart wrote: > Hello Frederic, > > On Sat, Feb 09, 2019 at 05:59:35PM +0200, Sakari Ailus wrote: > > Hi Frederic, > > > > Thanks for the patchset. > > > > Could you also cc the devicetree list, please? > > > > On Fri, Feb 01, 2019 at 07:21:27PM +0800, Frederic Chen wrote: > > > This patch adds the DT binding documentation for the shared memory > > > between DIP (Digital Image Processing) unit of the camera ISP system > > > and the co-processor in Mediatek SoCs. > > > > > > Signed-off-by: Frederic Chen <frederic.chen@xxxxxxxxxxxx> > > > --- > > > .../bindings/media/mediatek,dip_smem.txt | 29 ++++++++++++++++++++++ > > > 1 file changed, 29 insertions(+) > > > create mode 100644 Documentation/devicetree/bindings/media/mediatek,dip_smem.txt > > > > > > diff --git a/Documentation/devicetree/bindings/media/mediatek,dip_smem.txt b/Documentation/devicetree/bindings/media/mediatek,dip_smem.txt > > > new file mode 100644 > > > index 0000000..5533721 > > > --- /dev/null > > > +++ b/Documentation/devicetree/bindings/media/mediatek,dip_smem.txt > > > @@ -0,0 +1,29 @@ > > > +Mediatek ISP Shared Memory Device > > > + > > > +Mediatek ISP Shared Memory Device is used to manage shared memory > > > +among CPU, ISP IPs and coprocessor. It is associated with a reserved > > > +memory region (Please see Documentation\devicetree\bindings\ > > > +reserved-memory\mediatek,reserve-memory-isp_smem.txt) and > > > > s/\\/\//g; > > > > > +and provide the context to allocate memory with dma addresses. > > Does this represent a real device (as in IP core) in the SoC ? There > seems to be no driver associated with the compatible string defined > herein in this patch series, what is this node used for ? It does not represent a real device. It is used for creating the DIP-specific vb2 buffer allocation context (implemented in /drivers/media/platform/mtk-isp/isp_50/dip/mtk_dip-smem-drv.c). The compatible string has been renamed as “mediatek,dip_smem” in this patch series and I will correct it in this binding document. > > > > +Required properties: > > > +- compatible: Should be "mediatek,isp_smem" > > > > s/Should/Shall/ > > > > > + > > > +- iommus: should point to the respective IOMMU block with master port > > > > s/should/shall/ > > > > > + as argument. Please set the ports which may be accessed > > > + through the common path. You can see > > > + Documentation/devicetree/bindings/iommu/mediatek,iommu.txt > > > + for the detail. > > > + > > > +- mediatek,larb: must contain the local arbiters in the current Socs. > > > > Perhaps "SoCs"? > > > > > + Please set the larb of camsys for Pass 1 and imgsys for DIP, or both > > > + if you are using all the camera function. You can see > > > + Documentation/devicetree/bindings/memory-controllers/ > > > + mediatek,smi-larb.txt for the detail. > > > + > > > +Example: > > > + isp_smem: isp_smem { > > > + compatible = "mediatek,isp_smem"; > > > + mediatek,larb = <&larb5>; > > > + iommus = <&iommu M4U_PORT_CAM_IMGI>; > > > + }; > Sincerely, Frederic Chen