net: rswitch: Add Renesas Ethernet Switch

This patch adds Ethernet Switch support that found on R-Car S4
(r8a779f0) SoC. This is extracted from multiple patches from
downstream BSP, with additional rework of the network device
registration.

Signed-off-by: Hai Pham <hai.pham.ud@renesas.com>
Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>
Signed-off-by: Phong Hoang <phong.hoang.wz@renesas.com>
Signed-off-by: Takeshi Kihara <takeshi.kihara.df@renesas.com>
[Marek: Rework the driver to support all ports via subdrivers.
        Split the driver up, add generic PHY framework support.
	Generic code clean ups.]
Reviewed-by: Ramon Fried <rfried.dev@gmail.com>

drivers/net/Kconfig

@@ -752,6 +752,14 @@ config GMAC_ROCKCHIP
 	  This driver provides Rockchip SoCs network support based on the
 	  Synopsys Designware driver.
 
+config RENESAS_ETHER_SWITCH
+	bool "Renesas Ethernet Switch support"
+	depends on DM_ETH && R8A779F0
+	select PHYLIB
+	help
+	  This driver implements support for the Renesas Ethernet Switch
+	  which is available on R-Car S4 SoC (r8a779f0).
+
 config RENESAS_RAVB
 	bool "Renesas Ethernet AVB MAC"
 	depends on RCAR_64

drivers/net/Makefile

@@ -76,6 +76,7 @@ obj-$(CONFIG_OCTEONTX_SMI) += octeontx/smi.o
 obj-$(CONFIG_PCH_GBE) += pch_gbe.o
 obj-$(CONFIG_PCNET) += pcnet.o
 obj-$(CONFIG_PIC32_ETH) += pic32_mdio.o pic32_eth.o
+obj-$(CONFIG_RENESAS_ETHER_SWITCH) += rswitch.o
 obj-$(CONFIG_RENESAS_RAVB) += ravb.o
 obj-$(CONFIG_RTL8139) += rtl8139.o
 obj-$(CONFIG_RTL8169) += rtl8169.o