[PATCH 0/2] arm64: dts: qcom: msm8916/39: Make blsp_dma controlled-remotely

[PATCH 0/2] arm64: dts: qcom: msm8916/39: Make blsp_dma controlled-remotely

[Stephan Gerhold]

The blsp_dma controller is shared between the different subsystems, 
which is why it is already initialized by the firmware. We should not 
reinitialize it from Linux to avoid potential other users of the DMA 
engine to misbehave.

In mainline this can be described using the "qcom,controlled-remotely" 
property. In the downstream/vendor kernel from Qualcomm there is an 
opposite "qcom,managed-locally" property. This property is *not* set 
for the qcom,sps-dma@7884000 so adding "qcom,controlled-remotely" 
upstream matches the behavior of the downstream/vendor kernel.

Adding this seems to fix some weird issues with UART where both
input/output becomes garbled with certain obscure firmware versions on
some devices.

Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
---
Stephan Gerhold (2):
      arm64: dts: qcom: msm8916: Make blsp_dma controlled-remotely
      arm64: dts: qcom: msm8939: Make blsp_dma controlled-remotely

 arch/arm64/boot/dts/qcom/msm8916.dtsi | 1 +
 arch/arm64/boot/dts/qcom/msm8939.dtsi | 1 +
 2 files changed, 2 insertions(+)
---
base-commit: adcad44bd1c73a5264bff525e334e2f6fc01bb9b
change-id: 20231204-msm8916-blsp-dma-remote-516df8aac521

Best regards,
-- 
Stephan Gerhold <stephan@gerhold.net>

[PATCH 1/2] arm64: dts: qcom: msm8916: Make blsp_dma controlled-remotely

[Stephan Gerhold]

The blsp_dma controller is shared between the different subsystems,
which is why it is already initialized by the firmware. We should not
reinitialize it from Linux to avoid potential other users of the DMA
engine to misbehave.

In mainline this can be described using the "qcom,controlled-remotely"
property. In the downstream/vendor kernel from Qualcomm there is an
opposite "qcom,managed-locally" property. This property is *not* set
for the qcom,sps-dma@7884000 [1] so adding "qcom,controlled-remotely"
upstream matches the behavior of the downstream/vendor kernel.

Adding this seems to fix some weird issues with UART where both
input/output becomes garbled with certain obscure firmware versions on
some devices.

[1]: https://git.codelinaro.org/clo/la/kernel/msm-3.10/-/blob/LA.BR.1.2.9.1-02310-8x16.0/arch/arm/boot/dts/qcom/msm8916.dtsi#L1466-1472

Cc: <stable@vger.kernel.org> # 6.5
Fixes: a0e5fb103150 ("arm64: dts: qcom: Add msm8916 BLSP device nodes")
Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
---
This should only be backported to v6.5+ since it depends on commit
8975dd41a9db ("dmaengine: qcom: bam_dma: allow omitting
num-{channels,ees}") which landed in v6.5.
---
 arch/arm64/boot/dts/qcom/msm8916.dtsi | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm64/boot/dts/qcom/msm8916.dtsi b/arch/arm64/boot/dts/qcom/msm8916.dtsi
index e8a14dd7e7c2..7f8327b0dbdb 100644
--- a/arch/arm64/boot/dts/qcom/msm8916.dtsi
+++ b/arch/arm64/boot/dts/qcom/msm8916.dtsi
@@ -2155,6 +2155,7 @@ blsp_dma: dma-controller@7884000 {
 			clock-names = "bam_clk";
 			#dma-cells = <1>;
 			qcom,ee = <0>;
+			qcom,controlled-remotely;
 		};
 
 		blsp_uart1: serial@78af000 {

-- 
2.43.0

Re: [PATCH 1/2] arm64: dts: qcom: msm8916: Make blsp_dma controlled-remotely

[Bryan O'Donoghue]

On 04/12/2023 11:21, Stephan Gerhold wrote:
> The blsp_dma controller is shared between the different subsystems,
> which is why it is already initialized by the firmware. We should not
> reinitialize it from Linux to avoid potential other users of the DMA
> engine to misbehave.
> 
> In mainline this can be described using the "qcom,controlled-remotely"
> property. In the downstream/vendor kernel from Qualcomm there is an
> opposite "qcom,managed-locally" property. This property is *not* set
> for the qcom,sps-dma@7884000 [1] so adding "qcom,controlled-remotely"
> upstream matches the behavior of the downstream/vendor kernel.
> 
> Adding this seems to fix some weird issues with UART where both
> input/output becomes garbled with certain obscure firmware versions on
> some devices.
> 
> [1]: https://git.codelinaro.org/clo/la/kernel/msm-3.10/-/blob/LA.BR.1.2.9.1-02310-8x16.0/arch/arm/boot/dts/qcom/msm8916.dtsi#L1466-1472
> 
> Cc: <stable@vger.kernel.org> # 6.5
> Fixes: a0e5fb103150 ("arm64: dts: qcom: Add msm8916 BLSP device nodes")
> Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
> ---
> This should only be backported to v6.5+ since it depends on commit
> 8975dd41a9db ("dmaengine: qcom: bam_dma: allow omitting
> num-{channels,ees}") which landed in v6.5.
> ---
>   arch/arm64/boot/dts/qcom/msm8916.dtsi | 1 +
>   1 file changed, 1 insertion(+)
> 
> diff --git a/arch/arm64/boot/dts/qcom/msm8916.dtsi b/arch/arm64/boot/dts/qcom/msm8916.dtsi
> index e8a14dd7e7c2..7f8327b0dbdb 100644
> --- a/arch/arm64/boot/dts/qcom/msm8916.dtsi
> +++ b/arch/arm64/boot/dts/qcom/msm8916.dtsi
> @@ -2155,6 +2155,7 @@ blsp_dma: dma-controller@7884000 {
>   			clock-names = "bam_clk";
>   			#dma-cells = <1>;
>   			qcom,ee = <0>;
> +			qcom,controlled-remotely;
>   		};
>   
>   		blsp_uart1: serial@78af000 {
> 

Reviewed-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>

[PATCH 2/2] arm64: dts: qcom: msm8939: Make blsp_dma controlled-remotely

[Stephan Gerhold]

The blsp_dma controller is shared between the different subsystems,
which is why it is already initialized by the firmware. We should not
reinitialize it from Linux to avoid potential other users of the DMA
engine to misbehave.

In mainline this can be described using the "qcom,controlled-remotely"
property. In the downstream/vendor kernel from Qualcomm there is an
opposite "qcom,managed-locally" property. This property is *not* set
for the qcom,sps-dma@7884000 [1] so adding "qcom,controlled-remotely"
upstream matches the behavior of the downstream/vendor kernel.

Adding this seems to fix some weird issues with UART where both
input/output becomes garbled with certain obscure firmware versions on
some devices.

[1]: https://git.codelinaro.org/clo/la/kernel/msm-3.10/-/blob/LA.BR.1.2.9.1-02310-8x16.0/arch/arm/boot/dts/qcom/msm8939-common.dtsi#L866-872

Cc: <stable@vger.kernel.org> # 6.5
Fixes: 61550c6c156c ("arm64: dts: qcom: Add msm8939 SoC")
Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
---
This should only be backported to v6.5+ since it depends on commit
8975dd41a9db ("dmaengine: qcom: bam_dma: allow omitting
num-{channels,ees}") which landed in v6.5.
---
 arch/arm64/boot/dts/qcom/msm8939.dtsi | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm64/boot/dts/qcom/msm8939.dtsi b/arch/arm64/boot/dts/qcom/msm8939.dtsi
index 95610a32750a..9eb8f1ceee99 100644
--- a/arch/arm64/boot/dts/qcom/msm8939.dtsi
+++ b/arch/arm64/boot/dts/qcom/msm8939.dtsi
@@ -1761,6 +1761,7 @@ blsp_dma: dma-controller@7884000 {
 			clock-names = "bam_clk";
 			#dma-cells = <1>;
 			qcom,ee = <0>;
+			qcom,controlled-remotely;
 		};
 
 		blsp_uart1: serial@78af000 {

-- 
2.43.0

Re: [PATCH 2/2] arm64: dts: qcom: msm8939: Make blsp_dma controlled-remotely

[Bryan O'Donoghue]

On 04/12/2023 11:21, Stephan Gerhold wrote:
> The blsp_dma controller is shared between the different subsystems,
> which is why it is already initialized by the firmware. We should not
> reinitialize it from Linux to avoid potential other users of the DMA
> engine to misbehave.
> 
> In mainline this can be described using the "qcom,controlled-remotely"
> property. In the downstream/vendor kernel from Qualcomm there is an
> opposite "qcom,managed-locally" property. This property is *not* set
> for the qcom,sps-dma@7884000 [1] so adding "qcom,controlled-remotely"
> upstream matches the behavior of the downstream/vendor kernel.
> 
> Adding this seems to fix some weird issues with UART where both
> input/output becomes garbled with certain obscure firmware versions on
> some devices.
> 
> [1]: https://git.codelinaro.org/clo/la/kernel/msm-3.10/-/blob/LA.BR.1.2.9.1-02310-8x16.0/arch/arm/boot/dts/qcom/msm8939-common.dtsi#L866-872
> 
> Cc: <stable@vger.kernel.org> # 6.5
> Fixes: 61550c6c156c ("arm64: dts: qcom: Add msm8939 SoC")
> Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
> ---
> This should only be backported to v6.5+ since it depends on commit
> 8975dd41a9db ("dmaengine: qcom: bam_dma: allow omitting
> num-{channels,ees}") which landed in v6.5.
> ---
>   arch/arm64/boot/dts/qcom/msm8939.dtsi | 1 +
>   1 file changed, 1 insertion(+)
> 
> diff --git a/arch/arm64/boot/dts/qcom/msm8939.dtsi b/arch/arm64/boot/dts/qcom/msm8939.dtsi
> index 95610a32750a..9eb8f1ceee99 100644
> --- a/arch/arm64/boot/dts/qcom/msm8939.dtsi
> +++ b/arch/arm64/boot/dts/qcom/msm8939.dtsi
> @@ -1761,6 +1761,7 @@ blsp_dma: dma-controller@7884000 {
>   			clock-names = "bam_clk";
>   			#dma-cells = <1>;
>   			qcom,ee = <0>;
> +			qcom,controlled-remotely;
>   		};
>   
>   		blsp_uart1: serial@78af000 {
> 

Reviewed-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>

Re: [PATCH 0/2] arm64: dts: qcom: msm8916/39: Make blsp_dma controlled-remotely

[Bjorn Andersson]

On Mon, 04 Dec 2023 11:21:19 +0100, Stephan Gerhold wrote:
> The blsp_dma controller is shared between the different subsystems,
> which is why it is already initialized by the firmware. We should not
> reinitialize it from Linux to avoid potential other users of the DMA
> engine to misbehave.
> 
> In mainline this can be described using the "qcom,controlled-remotely"
> property. In the downstream/vendor kernel from Qualcomm there is an
> opposite "qcom,managed-locally" property. This property is *not* set
> for the qcom,sps-dma@7884000 so adding "qcom,controlled-remotely"
> upstream matches the behavior of the downstream/vendor kernel.
> 
> [...]

Applied, thanks!

[1/2] arm64: dts: qcom: msm8916: Make blsp_dma controlled-remotely
      commit: 7c45b6ddbcff01f9934d11802010cfeb0879e693
[2/2] arm64: dts: qcom: msm8939: Make blsp_dma controlled-remotely
      commit: 4bbda9421f316efdaef5dbf642e24925ef7de130

Best regards,
-- 
Bjorn Andersson <andersson@kernel.org>