Re: [PATCH v2] arm64: dts: qcom: msm8953: Add BLSP DMAs for I2C

[Stephan Gerhold <stephan@gerhold.net>]

On Tue, May 23, 2023 at 10:36:49PM +0200, Luca Weiss wrote:
> MSM8953 has two DMA controllers for the various I2C, SPI and UART
> busses. Add the nodes and configure all the I2C nodes so that the driver
> can use the DMA.
> 
> Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
> Signed-off-by: Luca Weiss <luca@z3ntu.xyz>
> ---
> Changes in v2:
> - Fix subject line, add "msm8953" (thanks Alexey)
> - Pick up tags
> - Link to v1: https://lore.kernel.org/r/20230422-msm8953-blsp-dma-v1-1-0024801bb587@z3ntu.xyz
> ---
>  arch/arm64/boot/dts/qcom/msm8953.dtsi | 48 +++++++++++++++++++++++++++++++++++
>  1 file changed, 48 insertions(+)
> 
> diff --git a/arch/arm64/boot/dts/qcom/msm8953.dtsi b/arch/arm64/boot/dts/qcom/msm8953.dtsi
> index 602cb188a635..c9b589353918 100644
> --- a/arch/arm64/boot/dts/qcom/msm8953.dtsi
> +++ b/arch/arm64/boot/dts/qcom/msm8953.dtsi
> @@ -1274,6 +1274,19 @@ opp-200000000 {
>  			};
>  		};
>  
> +		blsp1_dma: dma-controller@7884000 {
> +			compatible = "qcom,bam-v1.7.0";
> +			reg = <0x07884000 0x1f000>;
> +			interrupts = <GIC_SPI 238 IRQ_TYPE_LEVEL_HIGH>;
> +			clocks = <&gcc GCC_BLSP1_AHB_CLK>;
> +			clock-names = "bam_clk";
> +			num-channels = <12>;
> +			#dma-cells = <1>;
> +			qcom,ee = <0>;
> +			qcom,num-ees = <4>;

You can omit num-channels/qcom,num-ees here if you have a clock.

"dmaengine: qcom: bam_dma: allow omitting num-{channels,ees}" [1] helps
with doing this, although it also works without the patch. (The patch
just avoids a non-critical error in dmesg...)

[1]: https://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine.git/commit/?id=8975dd41a9dbca3b47f7b8dac5bc4dfb23011000

> +		blsp2_dma: dma-controller@7ac4000 {
> +			compatible = "qcom,bam-v1.7.0";
> +			reg = <0x07ac4000 0x1f000>;
> +			interrupts = <GIC_SPI 239 IRQ_TYPE_LEVEL_HIGH>;
> +			clocks = <&gcc GCC_BLSP2_AHB_CLK>;
> +			clock-names = "bam_clk";
> +			num-channels = <12>;
> +			#dma-cells = <1>;
> +			qcom,ee = <0>;
> +			qcom,num-ees = <4>;

Same here.

Thanks,
Stephan