From: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Date: Tue, 25 Feb 2025 13:44:40 +0000 (+0100)
Subject: Revert "arm64: dts: qcom: sdm845: Affirm IDR0.CCTW on apps_smmu"
X-Git-Tag: v6.14~25^2~5^2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f00db31d235946853fb430de8c6aa1295efc8353;p=thirdparty%2Fkernel%2Fstable.git

Revert "arm64: dts: qcom: sdm845: Affirm IDR0.CCTW on apps_smmu"

There are reports that the pagetable walker cache coherency is not a
given across the spectrum of SDM845/850 devices, leading to lock-ups
and resets. It works fine on some devices (like the Dragonboard 845c,
but not so much on the Lenovo Yoga C630).

This unfortunately looks like a fluke in firmware development, where
likely somewhere in the vast hypervisor stack, a change to accommodate
for this was only introduced after the initial software release (which
often serves as a baseline for products).

Revert the change to avoid additional guesswork around crashes.

This reverts commit 6b31a9744b8726c69bb0af290f8475a368a4b805.

Reported-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Closes: https://lore.kernel.org/linux-arm-msm/20250215-yoga-dma-coherent-v1-1-2419ee184a81@linaro.org/
Fixes: 6b31a9744b87 ("arm64: dts: qcom: sdm845: Affirm IDR0.CCTW on apps_smmu")
Signed-off-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20250225-topic-845_smmu_not_coherent-v1-1-98ca9d17471c@oss.qualcomm.com
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
---

diff --git a/arch/arm64/boot/dts/qcom/sdm845.dtsi b/arch/arm64/boot/dts/qcom/sdm845.dtsi
index e0ce804bb1a35..d0314cdf0b92f 100644
--- a/arch/arm64/boot/dts/qcom/sdm845.dtsi
+++ b/arch/arm64/boot/dts/qcom/sdm845.dtsi
@@ -5163,7 +5163,6 @@
 				     <GIC_SPI 341 IRQ_TYPE_LEVEL_HIGH>,
 				     <GIC_SPI 342 IRQ_TYPE_LEVEL_HIGH>,
 				     <GIC_SPI 343 IRQ_TYPE_LEVEL_HIGH>;
-			dma-coherent;
 		};
 
 		anoc_1_tbu: tbu@150c5000 {