[PATCH v4 2/2] arm64: dts: socfpga: agilex5: Add dma-coherent to XGMAC nodes

[muhammad . nazim . amirul . nazle . asmade]

From: Nazim Amirul <muhammad.nazim.amirul.nazle.asmade@xxxxxxxxxx>

The SMMU is enabled and transactions going through it are cache
coherent. Add the dma-coherent property to the XGMAC nodes to prevent
redundant cache flush/invalidate operations and potential stale data
issues.

Signed-off-by: Nazim Amirul <muhammad.nazim.amirul.nazle.asmade@xxxxxxxxxx>
---
Changes in v3:
- Fix commit header to follow subsystem naming convention (add agilex5: prefix)

Changes in v2:
- Move dma-coherent property into the base DTSI file instead of individual DTS files
---
 arch/arm64/boot/dts/intel/socfpga_agilex5.dtsi | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/arch/arm64/boot/dts/intel/socfpga_agilex5.dtsi b/arch/arm64/boot/dts/intel/socfpga_agilex5.dtsi
index daa1f9e0d1f5..3822f06c2694 100644
--- a/arch/arm64/boot/dts/intel/socfpga_agilex5.dtsi
+++ b/arch/arm64/boot/dts/intel/socfpga_agilex5.dtsi
@@ -576,6 +576,7 @@ gmac0: ethernet@10810000 {
 			altr,sysmgr-syscon = <&sysmgr 0x44 0>;
 			snps,clk-csr = <0>;
 			iommus = <&smmu 1>;
+			dma-coherent;
 			status = "disabled";
 
 			stmmac_axi_emac0_setup: stmmac-axi-config {
@@ -689,6 +690,7 @@ gmac1: ethernet@10820000 {
 			altr,sysmgr-syscon = <&sysmgr 0x48 0>;
 			snps,clk-csr = <0>;
 			iommus = <&smmu 2>;
+			dma-coherent;
 			status = "disabled";
 
 			stmmac_axi_emac1_setup: stmmac-axi-config {
@@ -802,6 +804,7 @@ gmac2: ethernet@10830000 {
 			altr,sysmgr-syscon = <&sysmgr 0x4c 0>;
 			snps,clk-csr = <0>;
 			iommus = <&smmu 3>;
+			dma-coherent;
 			status = "disabled";
 
 			stmmac_axi_emac2_setup: stmmac-axi-config {
-- 
2.43.7