linux-kernel - [PATCH 1/3] arm64: dts: qcom: msm8976: Make blsp

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20250613-bqx5plus-v1-1-2bc2d43707a6@apitzsch.eu>
Date: Fri, 13 Jun 2025 00:37:18 +0200
From: André Apitzsch via B4 Relay <devnull+git.apitzsch.eu@...nel.org>
To: Bjorn Andersson <andersson@...nel.org>, 
 Konrad Dybcio <konradybcio@...nel.org>, Rob Herring <robh@...nel.org>, 
 Krzysztof Kozlowski <krzk+dt@...nel.org>, 
 Conor Dooley <conor+dt@...nel.org>
Cc: ~postmarketos/upstreaming@...ts.sr.ht, phone-devel@...r.kernel.org, 
 linux-arm-msm@...r.kernel.org, devicetree@...r.kernel.org, 
 linux-kernel@...r.kernel.org, 
 André Apitzsch <git@...tzsch.eu>
Subject: [PATCH 1/3] arm64: dts: qcom: msm8976: Make blsp_dma
 controlled-remotely

From: André Apitzsch <git@...tzsch.eu>

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@...4000 and qcom,sps-dma@...4000 [1] so adding
"qcom,controlled-remotely" upstream matches the behavior of the
downstream/vendor kernel.

Adding this fixes booting Longcheer L9360.

[1]: https://git.codelinaro.org/clo/la/kernel/msm-3.10/-/blob/LA.BR.1.3.7.c26/arch/arm/boot/dts/qcom/msm8976.dtsi#L1149-1163

Signed-off-by: André Apitzsch <git@...tzsch.eu>
---
 arch/arm64/boot/dts/qcom/msm8976.dtsi | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/arm64/boot/dts/qcom/msm8976.dtsi b/arch/arm64/boot/dts/qcom/msm8976.dtsi
index e2ac2fd6882fcf47e846a92d45e0fcb9beba633a..2a30246384700dac2ec868c6f371248cfcc643fc 100644
--- a/arch/arm64/boot/dts/qcom/msm8976.dtsi
+++ b/arch/arm64/boot/dts/qcom/msm8976.dtsi
@@ -1331,6 +1331,7 @@ blsp1_dma: dma-controller@...4000 {
 			clock-names = "bam_clk";
 			#dma-cells = <1>;
 			qcom,ee = <0>;
+			qcom,controlled-remotely;
 		};
 
 		blsp1_uart1: serial@...f000 {
@@ -1451,6 +1452,7 @@ blsp2_dma: dma-controller@...4000 {
 			clock-names = "bam_clk";
 			#dma-cells = <1>;
 			qcom,ee = <0>;
+			qcom,controlled-remotely;
 		};
 
 		blsp2_uart2: serial@...0000 {

-- 
2.49.0