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,
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...
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 {
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.
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
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...
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 {
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.
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
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,
linux-stable-mirror@lists.linaro.org
-
Bjorn Andersson -
Bryan O'Donoghue -
Stephan Gerhold