[PATCH 22/22] arm64: dts: qcom: talos: Reserve low IOVA range for Venus

Venus VPU reserves IOVA addresses below 0x25800000 (600MB), primarily for
secure non-pixel buffers. DMA into that range, from any other stream id
would triggers unhandled SMMU page faults that cause spontaneous device
reboots. This is readily reproduced with one or more browser tabs
driving multiple concurrent video decode streams.

Add a reserved-memory IOVA reservation node covering [0, 0x25800000]
and reference it from the venus node so the IOMMU layer keeps DMA
allocations above that boundary.

Fixes: b83d3cc7a59c ("arm64: dts: qcom: sm6150: add venus node to devicetree")
Cc: [email protected]
Signed-off-by: Vikash Garodia <[email protected]>
---
 arch/arm64/boot/dts/qcom/talos.dtsi | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/boot/dts/qcom/talos.dtsi b/arch/arm64/boot/dts/qcom/talos.dtsi
index eedfdce3c479e704537fb8df7345452fe063d9c3..8645b04e266438857647600f4cf129dec9951c53 100644
--- a/arch/arm64/boot/dts/qcom/talos.dtsi
+++ b/arch/arm64/boot/dts/qcom/talos.dtsi
@@ -687,6 +687,17 @@ adsp_rpc_remote_heap_mem: adsp-rpc-remote-heap {
 			alignment = <0x0 0x400000>;
 			size = <0x0 0x800000>;
 		};
+
+		/*
+		 * The Venus VPU reserves IOVA below 0x25800000 (600MB),
+		 * primarily for non-pixel buffers using different Stream IDs.
+		 * DMA into that range triggers unhandled SMMU faults and
+		 * spontaneous reboots, so reserve it to keep IOMMU
+		 * allocations above this boundary.
+		 */
+		venus_iova: venus-iova {
+			iommu-addresses = <&venus 0x0 0x0 0x0 0x25800000>;
+		};
 	};
 
 	soc: soc@0 {
@@ -4116,7 +4127,7 @@ &mc_virt SLAVE_EBI1 QCOM_ICC_TAG_ALWAYS>,
 
 			iommus = <&apps_smmu 0xe60 0x20>;
 
-			memory-region = <&pil_video_mem>;
+			memory-region = <&pil_video_mem>, <&venus_iova>;
 
 			status = "disabled";
 

-- 
2.34.1