diff mbox series

[v3,1/2] dt-bindings: dmaengine: bam_dma: Add "powered remotely" mode

Message ID 20211018102421.19848-2-stephan@gerhold.net (mailing list archive)
State Not Applicable
Headers show
Series dmaengine: qcom: bam_dma: Add "powered remotely" mode for BAM-DMUX | expand

Commit Message

Stephan Gerhold Oct. 18, 2021, 10:24 a.m. UTC
In some configurations, the BAM DMA controller is set up by a remote
processor and the local processor can simply start making use of it
without setting up the BAM. This is already supported using the
"qcom,controlled-remotely" property.

However, for some reason another possible configuration is that the
remote processor is responsible for powering up the BAM, but we are
still responsible for initializing it (e.g. resetting it etc). Add
a "qcom,powered-remotely" property to describe that configuration.

Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
---
Changes in v3: None, split from BAM-DMUX patch set
Changes since RFC:
  - Rename qcom,remote-power-collapse -> qcom,powered-remotely
    for consistency with "qcom,controlled-remotely"

Also note that there is an ongoing effort to convert these bindings
to DT schema but sadly there were not any updates for a while. :/
https://lore.kernel.org/linux-arm-msm/20210519143700.27392-2-bhupesh.sharma@linaro.org/
---
 Documentation/devicetree/bindings/dma/qcom_bam_dma.txt | 2 ++
 1 file changed, 2 insertions(+)

Comments

Rob Herring Oct. 18, 2021, 7:51 p.m. UTC | #1
On Mon, 18 Oct 2021 12:24:20 +0200, Stephan Gerhold wrote:
> In some configurations, the BAM DMA controller is set up by a remote
> processor and the local processor can simply start making use of it
> without setting up the BAM. This is already supported using the
> "qcom,controlled-remotely" property.
> 
> However, for some reason another possible configuration is that the
> remote processor is responsible for powering up the BAM, but we are
> still responsible for initializing it (e.g. resetting it etc). Add
> a "qcom,powered-remotely" property to describe that configuration.
> 
> Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
> ---
> Changes in v3: None, split from BAM-DMUX patch set
> Changes since RFC:
>   - Rename qcom,remote-power-collapse -> qcom,powered-remotely
>     for consistency with "qcom,controlled-remotely"
> 
> Also note that there is an ongoing effort to convert these bindings
> to DT schema but sadly there were not any updates for a while. :/
> https://lore.kernel.org/linux-arm-msm/20210519143700.27392-2-bhupesh.sharma@linaro.org/
> ---
>  Documentation/devicetree/bindings/dma/qcom_bam_dma.txt | 2 ++
>  1 file changed, 2 insertions(+)
> 

Acked-by: Rob Herring <robh@kernel.org>
diff mbox series

Patch

diff --git a/Documentation/devicetree/bindings/dma/qcom_bam_dma.txt b/Documentation/devicetree/bindings/dma/qcom_bam_dma.txt
index cf5b9e44432c..6e9a5497b3f2 100644
--- a/Documentation/devicetree/bindings/dma/qcom_bam_dma.txt
+++ b/Documentation/devicetree/bindings/dma/qcom_bam_dma.txt
@@ -15,6 +15,8 @@  Required properties:
   the secure world.
 - qcom,controlled-remotely : optional, indicates that the bam is controlled by
   remote proccessor i.e. execution environment.
+- qcom,powered-remotely : optional, indicates that the bam is powered up by
+  a remote processor but must be initialized by the local processor.
 - num-channels : optional, indicates supported number of DMA channels in a
   remotely controlled bam.
 - qcom,num-ees : optional, indicates supported number of Execution Environments