riscv: dts: starfive: jh7100: Add sysmain and gmac DT nodes

Provide the sysmain and gmac DT nodes supporting the DWMAC found on the
StarFive JH7100 SoC.
Co-developed-by: Emil Renner Berthing <emil.renner.berthing@canonical.com>
Signed-off-by: Emil Renner Berthing <emil.renner.berthing@canonical.com>
Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@collabora.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed-by: Emil Renner Berthing <emil.renner.berthing@canonical.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>

arch/riscv/boot/dts/starfive/jh7100.dtsi

@@ -204,6 +204,37 @@ sdio1: mmc@10010000 {
 			status = "disabled";
 		};
 
+		gmac: ethernet@10020000 {
+			compatible = "starfive,jh7100-dwmac", "snps,dwmac";
+			reg = <0x0 0x10020000 0x0 0x10000>;
+			clocks = <&clkgen JH7100_CLK_GMAC_ROOT_DIV>,
+				 <&clkgen JH7100_CLK_GMAC_AHB>,
+				 <&clkgen JH7100_CLK_GMAC_PTP_REF>,
+				 <&clkgen JH7100_CLK_GMAC_TX_INV>,
+				 <&clkgen JH7100_CLK_GMAC_GTX>;
+			clock-names = "stmmaceth", "pclk", "ptp_ref", "tx", "gtx";
+			resets = <&rstgen JH7100_RSTN_GMAC_AHB>;
+			reset-names = "ahb";
+			interrupts = <6>, <7>;
+			interrupt-names = "macirq", "eth_wake_irq";
+			max-frame-size = <9000>;
+			snps,multicast-filter-bins = <32>;
+			snps,perfect-filter-entries = <128>;
+			starfive,syscon = <&sysmain 0x70 0>;
+			rx-fifo-depth = <32768>;
+			tx-fifo-depth = <16384>;
+			snps,axi-config = <&stmmac_axi_setup>;
+			snps,fixed-burst;
+			snps,force_thresh_dma_mode;
+			status = "disabled";
+
+			stmmac_axi_setup: stmmac-axi-config {
+				snps,wr_osr_lmt = <16>;
+				snps,rd_osr_lmt = <16>;
+				snps,blen = <256 128 64 32 0 0 0>;
+			};
+		};
+
 		clkgen: clock-controller@11800000 {
 			compatible = "starfive,jh7100-clkgen";
 			reg = <0x0 0x11800000 0x0 0x10000>;
@@ -218,6 +249,11 @@ rstgen: reset-controller@11840000 {
 			#reset-cells = <1>;
 		};
 
+		sysmain: syscon@11850000 {
+			compatible = "starfive,jh7100-sysmain", "syscon";
+			reg = <0x0 0x11850000 0x0 0x10000>;
+		};
+
 		i2c0: i2c@118b0000 {
 			compatible = "snps,designware-i2c";
 			reg = <0x0 0x118b0000 0x0 0x10000>;