Re: [PATCH 2/2] dmaengine: qcom_bam_dma: Bypass BAM init if not managed locally

From: Rob Herring
Date: Wed Mar 23 2016 - 11:09:20 EST


On Tue, Mar 22, 2016 at 03:19:11PM +0530, Pramod Gurav wrote:
> On some QOCM platforms BAM control registers are managed remotely

s/QOCM/QCOM/

> hence can not be accessed by application processor for writes. Pass
> a DT property qcom,bam_ctrl_remote to declare the same to skip bam_init.

Is this a property of specific SOCs or a configuration option? If the
former, use the SOC specific compatible string to determine this option.

> Move the pipe number initialisation from bam_init to probe functiom
> as it should be done for all platforms.
>
> Signed-off-by: Pramod Gurav <gpramod@xxxxxxxxxxxxxx>
> ---
> Documentation/devicetree/bindings/dma/qcom_bam_dma.txt | 3 +++
> drivers/dma/qcom/bam_dma.c | 18 +++++++++++-------
> 2 files changed, 14 insertions(+), 7 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/dma/qcom_bam_dma.txt b/Documentation/devicetree/bindings/dma/qcom_bam_dma.txt
> index 1c9d48e..46e33ae 100644
> --- a/Documentation/devicetree/bindings/dma/qcom_bam_dma.txt
> +++ b/Documentation/devicetree/bindings/dma/qcom_bam_dma.txt
> @@ -13,6 +13,8 @@ Required properties:
> - clock-names: must contain "bam_clk" entry
> - qcom,ee : indicates the active Execution Environment identifier (0-7) used in
> the secure world.
> +- qcom,bam_ctrl_remote: Use when BAM global device control is managed remotely

Don't use '_' in property names.

> + and not locally by the application processor.
>
> Example:
>
> @@ -24,6 +26,7 @@ Example:
> clock-names = "bam_clk";
> #dma-cells = <1>;
> qcom,ee = <0>;
> + qcom,bam_ctrl_remote;
> };
>
> DMA clients must use the format described in the dma.txt file, using a two cell