[PATCH] arm64: dts: qcom: glymur-asus-zenbook: Drop the CMA region

[PATCH] arm64: dts: qcom: glymur-asus-zenbook: Drop the CMA region

[Abel Vesa]

The linux,cma reserved-memory region was carried over from the X1E80100
boards, where it is needed because the PCIe SMMU is reserved (owned by
the hypervisor) and PCIe devices such as the WCN7850 WLAN end up doing
DMA to physically contiguous memory.

On Glymur the PCIe SMMU is owned by Linux and the devices behind it are
attached to translated IOMMU domains, so there is no need for a large
contiguous DMA pool. Describing a CMA size in the DT is also more of a
use-case policy than a hardware description. None of the other Glymur
boards reserve one, so drop it from the two ASUS Zenbooks as well.

Assisted-by: LLM
Signed-off-by: Abel Vesa <abel.vesa@oss.qualcomm.com>
---
 arch/arm64/boot/dts/qcom/glymur-asus-zenbook-a14-ux3407na.dts | 9 ---------
 arch/arm64/boot/dts/qcom/glymur-asus-zenbook-a16-ux3607oa.dts | 9 ---------
 2 files changed, 18 deletions(-)

diff --git a/arch/arm64/boot/dts/qcom/glymur-asus-zenbook-a14-ux3407na.dts b/arch/arm64/boot/dts/qcom/glymur-asus-zenbook-a14-ux3407na.dts
index e96e65a0c5b4..83d15abf9b0d 100644
--- a/arch/arm64/boot/dts/qcom/glymur-asus-zenbook-a14-ux3407na.dts
+++ b/arch/arm64/boot/dts/qcom/glymur-asus-zenbook-a14-ux3407na.dts
@@ -263,15 +263,6 @@ vreg_wcn_3p3: regulator-wcn-3p3 {
 		regulator-boot-on;
 	};
 
-	reserved-memory {
-		linux,cma {
-			compatible = "shared-dma-pool";
-			size = <0x0 0x10000000>;
-			reusable;
-			linux,cma-default;
-		};
-	};
-
 	sound {
 		compatible = "qcom,glymur-sndcard";
 		model = "GLYMUR-ASUS-Zenbook-A14-UX3407NA";
diff --git a/arch/arm64/boot/dts/qcom/glymur-asus-zenbook-a16-ux3607oa.dts b/arch/arm64/boot/dts/qcom/glymur-asus-zenbook-a16-ux3607oa.dts
index 95da35125d75..207190f2be79 100644
--- a/arch/arm64/boot/dts/qcom/glymur-asus-zenbook-a16-ux3607oa.dts
+++ b/arch/arm64/boot/dts/qcom/glymur-asus-zenbook-a16-ux3607oa.dts
@@ -275,15 +275,6 @@ vreg_wcn_3p3: regulator-wcn-3p3 {
 		regulator-boot-on;
 	};
 
-	reserved-memory {
-		linux,cma {
-			compatible = "shared-dma-pool";
-			size = <0x0 0x10000000>;
-			reusable;
-			linux,cma-default;
-		};
-	};
-
 	sound {
 		compatible = "qcom,glymur-sndcard";
 		model = "GLYMUR-ASUS-Zenbook-A16-UX3607OA";

---
base-commit: 1fffefb00cc0b0da1f2ae24e3d33364530ea6515
change-id: 20261014-dts-qcom-glymur-asus-drop-cma-591289d6d491

Best regards,
--  
Abel Vesa <abel.vesa@oss.qualcomm.com>

Re: [PATCH] arm64: dts: qcom: glymur-asus-zenbook: Drop the CMA region

[Konrad Dybcio]

On 10/14/26 3:55 PM, Abel Vesa wrote:
> The linux,cma reserved-memory region was carried over from the X1E80100
> boards, where it is needed because the PCIe SMMU is reserved (owned by
> the hypervisor) and PCIe devices such as the WCN7850 WLAN end up doing
> DMA to physically contiguous memory.
> 
> On Glymur the PCIe SMMU is owned by Linux and the devices behind it are
> attached to translated IOMMU domains, so there is no need for a large
> contiguous DMA pool. Describing a CMA size in the DT is also more of a
> use-case policy than a hardware description. None of the other Glymur
> boards reserve one, so drop it from the two ASUS Zenbooks as well.
> 
> Assisted-by: LLM
> Signed-off-by: Abel Vesa <abel.vesa@oss.qualcomm.com>
> ---

Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Tested-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com> # Zenbook A16

Konrad