Hi Rob,
On 02/22/2017 02:09 AM, Rob Herring wrote:
> On Tue, Feb 07, 2017 at 03:10:17PM +0200, Stanimir Varbanov wrote:
>> Add binding document for Venus video encoder/decoder driver
>>
>> Cc: Rob Herring <robh...@kernel.org>
>> Cc: devicet...@vger.kernel.org
>> Signed-off-by: Stanimir Varbanov <stanimir.varba...@linaro.org>
>> ---
>> Changes since previous v5:
>> * dropped rproc phandle (remoteproc is not used anymore)
>> * added subnodes paragraph with descrition of three subnodes:
>> - video-decoder and video-encoder - describes decoder (core0) and
>> encoder (core1) power-domains and clocks (applicable for msm8996
>> Venus core).
>> - video-firmware - needed to get reserved memory region where the
>> firmware is stored.
>>
>> .../devicetree/bindings/media/qcom,venus.txt | 112
>> +++++++++++++++++++++
>> 1 file changed, 112 insertions(+)
>> create mode 100644 Documentation/devicetree/bindings/media/qcom,venus.txt
>>
>> diff --git a/Documentation/devicetree/bindings/media/qcom,venus.txt
>> b/Documentation/devicetree/bindings/media/qcom,venus.txt
>> new file mode 100644
>> index 000000000000..4427af3ca5a5
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/media/qcom,venus.txt
>> @@ -0,0 +1,112 @@
>
> [...]
>
>> +* Subnodes
>> +The Venus node must contain three subnodes representing video-decoder,
>> +video-encoder and video-firmware.
>
> [...]
>
>> +The video-firmware subnode should contain:
>> +
>> +- memory-region:
>> + Usage: required
>> + Value type: <phandle>
>> + Definition: reference to the reserved-memory for the memory region
>> +
>> +* An Example
>> + video-codec@1d00000 {
>> + compatible = "qcom,msm8916-venus";
>> + reg = <0x01d00000 0xff000>;
>> + interrupts = <GIC_SPI 44 IRQ_TYPE_LEVEL_HIGH>;
>> + clocks = <&gcc GCC_VENUS0_VCODEC0_CLK>,
>> + <&gcc GCC_VENUS0_AHB_CLK>,
>> + <&gcc GCC_VENUS0_AXI_CLK>;
>> + clock-names = "core", "iface", "bus";
>> + power-domains = <&gcc VENUS_GDSC>;
>> + iommus = <&apps_iommu 5>;
>> +
>> + video-decoder {
>> + compatible = "venus-decoder";
>> + clocks = <&mmcc VIDEO_SUBCORE0_CLK>;
>> + clock-names = "core";
>> + power-domains = <&mmcc VENUS_CORE0_GDSC>;
>> + };
>> +
>> + video-encoder {
>> + compatible = "venus-encoder";
>> + clocks = <&mmcc VIDEO_SUBCORE1_CLK>;
>> + clock-names = "core";
>> + power-domains = <&mmcc VENUS_CORE1_GDSC>;
>> + };
>> +
>> + video-firmware {
>> + memory-region = <&venus_mem>;
>
> Why does this need to be a sub node?
Because firmware reserved memory region must have separate struct
device, otherwise allocating video buffers (and map them through iommu)
for video-codec will fail because dma_alloc_coherent trying to allocate
from per-device coherent area.
--
regards,
Stan
