On Thu, Feb 20, 2020 at 12:27 PM Jordan Crouse <jcrouse@xxxxxxxxxxxxxx> wrote: > > The GMU node now requires a specific dma-range property so that the driver s/dma-range/dma-ranges/ here and the subject. > can use the DMA API to do the few memory allocations required by the GMU. > This sets the IOMMU iova allocator to match the 'uncached' part of the > GMU virtual address space. Sounds like a bunch of kernel things and this is a binding. > > v2: Fix the dma-ranges tag. The third pair should be the size. > > Signed-off-by: Jordan Crouse <jcrouse@xxxxxxxxxxxxxx> > --- > > Documentation/devicetree/bindings/display/msm/gmu.yaml | 10 ++++++++++ > 1 file changed, 10 insertions(+) > > diff --git a/Documentation/devicetree/bindings/display/msm/gmu.yaml b/Documentation/devicetree/bindings/display/msm/gmu.yaml > index 776ff92..d11a073 100644 > --- a/Documentation/devicetree/bindings/display/msm/gmu.yaml > +++ b/Documentation/devicetree/bindings/display/msm/gmu.yaml > @@ -83,6 +83,13 @@ properties: > Phandle to the OPP table for the available GMU frequencies. Refer to > ../../opp/opp.txt for more information. > > + dma-ranges: dma-ranges is a bus property and doesn't go in device nodes (that don't implement a bus like PCI host for example). This would not have even worked a few kernel versions back because the kernel would only start looking for dma-ranges in a parent node. > + $ref: /schemas/types.yaml#/definitions/uint32-array > + description: > + Describe the dma-address range for the device. This should always > + describe the range between 0x60000000 and 0x80000000 which represents If this is always the region, then why does it need to be in DT? Just set your dma_mask which drivers should be doing if they want anything other than (2^32 - 1). dma-ranges sets the bus_dma_mask. > + the uncached region of the GMU address space. > + > required: > - compatible > - reg > @@ -95,6 +102,7 @@ required: > - power-domain-names > - iommus > - operating-points-v2 > + - dma-ranges > > examples: > - | > @@ -127,4 +135,6 @@ examples: > > iommus = <&adreno_smmu 5>; > operating-points-v2 = <&gmu_opp_table>; > + > + dma-ranges = <0 0x60000000 0 0x60000000 0 0x20000000>; > }; > -- > 2.7.4 >
