This is a note to let you know that I've just added the patch titled
arm64: dts: qcom: msm8916: Make blsp_dma controlled-remotely
to the 6.1-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
arm64-dts-qcom-msm8916-make-blsp_dma-controlled-remo.patch
and it can be found in the queue-6.1 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 13f10d6f5288ae87534d3156fd4157b80c99b4b0
Author: Stephan Gerhold <stephan@xxxxxxxxxxx>
Date: Mon Dec 4 11:21:20 2023 +0100
arm64: dts: qcom: msm8916: Make blsp_dma controlled-remotely
[ Upstream commit 7c45b6ddbcff01f9934d11802010cfeb0879e693 ]
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@xxxxxxxxxxxxxxx # 6.5
Fixes: a0e5fb103150 ("arm64: dts: qcom: Add msm8916 BLSP device nodes")
Signed-off-by: Stephan Gerhold <stephan@xxxxxxxxxxx>
Reviewed-by: Bryan O'Donoghue <bryan.odonoghue@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20231204-msm8916-blsp-dma-remote-v1-1-3e49c8838c8d@xxxxxxxxxxx
Signed-off-by: Bjorn Andersson <andersson@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/arch/arm64/boot/dts/qcom/msm8916.dtsi b/arch/arm64/boot/dts/qcom/msm8916.dtsi
index f0d097ade84c..987cebbda057 100644
--- a/arch/arm64/boot/dts/qcom/msm8916.dtsi
+++ b/arch/arm64/boot/dts/qcom/msm8916.dtsi
@@ -1522,6 +1522,7 @@ blsp_dma: dma-controller@7884000 {
clock-names = "bam_clk";
#dma-cells = <1>;
qcom,ee = <0>;
+ qcom,controlled-remotely;
};
blsp1_uart1: serial@78af000 {
