[PATCH 2/2] riscv: dts: sophgo: Add dma-coherent to SG2042 PCIe controllers

Han Gao gaohan at iscas.ac.cn
Tue Mar 31 10:12:48 PDT 2026


SG2042's PCIe root complexes are cache-coherent with the CPU. Mark all
four PCIe controller nodes (pcie_rc0 through pcie_rc3) as dma-coherent
so the kernel uses coherent DMA mappings instead of non-coherent bounce
buffering.

Cc: stable at vger.kernel.org
Signed-off-by: Han Gao <gaohan at iscas.ac.cn>
---
 arch/riscv/boot/dts/sophgo/sg2042.dtsi | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/arch/riscv/boot/dts/sophgo/sg2042.dtsi b/arch/riscv/boot/dts/sophgo/sg2042.dtsi
index 9fddf3f0b3b9..3af770549742 100644
--- a/arch/riscv/boot/dts/sophgo/sg2042.dtsi
+++ b/arch/riscv/boot/dts/sophgo/sg2042.dtsi
@@ -417,6 +417,7 @@ pcie_rc0: pcie at 7060000000 {
 			vendor-id = <0x1f1c>;
 			device-id = <0x2042>;
 			cdns,no-bar-match-nbits = <48>;
+			dma-coherent;
 			msi-parent = <&msi>;
 			status = "disabled";
 		};
@@ -439,6 +440,7 @@ pcie_rc1: pcie at 7060800000 {
 			vendor-id = <0x1f1c>;
 			device-id = <0x2042>;
 			cdns,no-bar-match-nbits = <48>;
+			dma-coherent;
 			msi-parent = <&msi>;
 			status = "disabled";
 		};
@@ -461,6 +463,7 @@ pcie_rc2: pcie at 7062000000 {
 			vendor-id = <0x1f1c>;
 			device-id = <0x2042>;
 			cdns,no-bar-match-nbits = <48>;
+			dma-coherent;
 			msi-parent = <&msi>;
 			status = "disabled";
 		};
@@ -483,6 +486,7 @@ pcie_rc3: pcie at 7062800000 {
 			vendor-id = <0x1f1c>;
 			device-id = <0x2042>;
 			cdns,no-bar-match-nbits = <48>;
+			dma-coherent;
 			msi-parent = <&msi>;
 			status = "disabled";
 		};
-- 
2.47.3




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