net: stmmac: tegra: Add MGBE support

Add support for the Multi-Gigabit Ethernet (MGBE/XPCS) IP found on
NVIDIA Tegra234 SoCs.
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Bhadram Varka <vbhadram@nvidia.com>
Co-developed-by: Revanth Kumar Uppala <ruppala@nvidia.com>
Signed-off-by: Revanth Kumar Uppala <ruppala@nvidia.com>
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/stmicro/stmmac/Kconfig

@@ -235,6 +235,15 @@ config DWMAC_INTEL_PLAT
 	  the stmmac device driver. This driver is used for the Intel Keem Bay
 	  SoC.
 
+config DWMAC_TEGRA
+	tristate "NVIDIA Tegra MGBE support"
+	depends on ARCH_TEGRA || COMPILE_TEST
+	help
+	  This selects the Multi-GigaBit Ethernet (MGBE) Controller that is
+	  found on the NVIDIA Tegra SoC devices. This driver provides the glue
+	  layer on top of the stmmac driver required for these NVIDIA Tegra SoC
+	  devices.
+
 config DWMAC_VISCONTI
 	tristate "Toshiba Visconti DWMAC support"
 	default ARCH_VISCONTI

drivers/net/ethernet/stmicro/stmmac/Makefile

@@ -31,6 +31,7 @@ obj-$(CONFIG_DWMAC_DWC_QOS_ETH)	+= dwmac-dwc-qos-eth.o
 obj-$(CONFIG_DWMAC_INTEL_PLAT)	+= dwmac-intel-plat.o
 obj-$(CONFIG_DWMAC_GENERIC)	+= dwmac-generic.o
 obj-$(CONFIG_DWMAC_IMX8)	+= dwmac-imx.o
+obj-$(CONFIG_DWMAC_TEGRA)	+= dwmac-tegra.o
 obj-$(CONFIG_DWMAC_VISCONTI)	+= dwmac-visconti.o
 stmmac-platform-objs:= stmmac_platform.o
 dwmac-altr-socfpga-objs := altr_tse_pcs.o dwmac-socfpga.o