On Mon, Jan 11, 2016 at 3:39 PM, Laura Abbott <laura@xxxxxxxxxxxx> wrote: > > This adds a base set of devicetree bindings for the Ion memory > manager. This supports setting up the generic set of heaps and > their properties. > > Signed-off-by: Laura Abbott <laura@xxxxxxxxxxxx> > --- > drivers/staging/android/ion/devicetree.txt | 50 ++++++++++++++++++++++++++++++ > 1 file changed, 50 insertions(+) > create mode 100644 drivers/staging/android/ion/devicetree.txt > > diff --git a/drivers/staging/android/ion/devicetree.txt b/drivers/staging/android/ion/devicetree.txt > new file mode 100644 > index 0000000..e1ea537 > --- /dev/null > +++ b/drivers/staging/android/ion/devicetree.txt > @@ -0,0 +1,50 @@ > +Ion Memory Manager > + > +Ion is a memory manager that allows for sharing of buffers via dma-buf. > +Ion allows for different types of allocation via an abstraction called > +a 'heap'. A heap represents a specific type of memory. Each heap has > +a different type. There can be multiple instances of the same heap > +type. > + > +Required properties for Ion > + > +- compatible: "linux,ion" PLUS a compatible property for the device > + > +All child nodes of a linux,ion node are interpreted as heaps > + > +required properties for heaps > + > +- compatible: compatible string for a heap type PLUS a compatible property > +for the specific instance of the heap. Current heap types > +-- linux,ion-heap-system > +-- linux,ion-heap-system-contig > +-- linux,ion-heap-carveout > +-- linux,ion-heap-chunk > +-- linux,ion-heap-dma > +-- linux,ion-heap-custom > + > +Optional properties > +- memory-region: A phandle to a memory region. Required for DMA heap type > +(see reserved-memory.txt for details on the reservation) Why would all of them not require a memory region other than system heap? > + > +Example: > + > + ion { > + compatbile = "qcom,msm8916-ion", "linux,ion"; > + #address-cells = <1>; > + #size-cells = <0>; > + > + ion-system-heap { > + compatbile = "qcom,system-heap", "linux,ion-heap-system" > + }; What is the purpose of this in DT? Don't we always want/need a system heap? How does it vary by platform? > + ion-camera-region { > + compatible = "qcom,camera-heap", "linux,ion-heap-dma" > + memory-region = <&camera_region>; Why not just add a property (or properties) to the camera_region node that ION drivers can search for? Rob -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html