Messages in this thread | | | From | John Stultz <> | Date | Fri, 25 Oct 2019 16:55:35 -0700 | Subject | Re: [RFC][PATCH 1/3] dt-bindings: dma-buf: heaps: Describe CMA regions to be added to dmabuf heaps interface. |
| |
On Fri, Oct 25, 2019 at 4:32 PM Rob Herring <rob.e.herring@gmail.com> wrote: > > On Fri, Oct 25, 2019 at 5:51 PM John Stultz <john.stultz@linaro.org> wrote: > > > > This binding specifies which CMA regions should be added to the > > dmabuf heaps interface. > > Is this an ION DT binding in disguise? I thought I killed that. ;)
Maybe? I may not have been paying attention back then. :)
> > +Example: > > +This example has a camera CMA node in reserved memory, which is then > > +referenced by the dmabuf-heap-cma node. > > + > > + > > + reserved-memory { > > + #address-cells = <2>; > > + #size-cells = <2>; > > + ranges; > > + ... > > + cma_camera: cma-camera { > > + compatible = "shared-dma-pool"; > > + reg = <0x0 0x24C00000 0x0 0x4000000>; > > + reusable; > > + }; > > + ... > > + }; > > + > > + cma_heap { > > + compatible = "dmabuf-heap-cma"; > > + memory-region = <&cma_camera>; > > Why the indirection here? Can't you just add a flag property to > reserved-memory nodes like we do to flag CMA nodes?
Happy to try. Do you mean like with the "reuasable" tag? Or more like the "linux,cma-default" tag?
Do you have a preference for the flag name here?
> As I suspected, it's because in patch 2 you're just abusing DT to > instantiate platform devices. We already support binding drivers to > reserved-memory nodes directly.
Sorry, one of those "when all you know how to do is hammer, everything looks like a nail" issues. Is there a specific example for binding drivers to reserved-memory nodes I can try to follow?
Appreciate the review and feedback!
thanks -john
| |