net: designware: s700: Add glue code for S700 mac

This patchs adds glue logic to enable designware mac present on
Action Semi based S700 SoC, Configures SoC specific bits.

Undocumented bit that programs the PHY interface select register
comes from vendor source.

It has been tested on Cubieboard7-lite based on S700 SoC.
Signed-off-by: NAmit Singh Tomar <amittomer25@gmail.com>

arch/arm/include/asm/arch-owl/regs_s700.h

@@ -55,4 +55,10 @@
 
 #define CMU_DEVCLKEN1_ETH	BIT(23)
 
+#define GPIO_MFP_PWM           (0xE01B0000)
+#define MFP_CTL0               (GPIO_MFP_PWM + 0x40)
+#define MFP_CTL1               (GPIO_MFP_PWM + 0x44)
+#define MFP_CTL2               (GPIO_MFP_PWM + 0x48)
+#define MFP_CTL3               (GPIO_MFP_PWM + 0x4C)
+
 #endif

drivers/net/Kconfig

@@ -238,6 +238,13 @@ config ETH_DESIGNWARE_SOCFPGA
 	  Altera system manager to correctly interface with the PHY.
 	  This code handles those SoC specifics.
 
+config ETH_DESIGNWARE_S700
+	bool "Actins S700 glue driver for Synopsys Designware Ethernet MAC"
+	depends on DM_ETH && ETH_DESIGNWARE
+	help
+	  This provides glue layer to use Synopsys Designware Ethernet MAC
+	  present on Actions S700 SoC.
+
 config ETHOC
 	bool "OpenCores 10/100 Mbps Ethernet MAC"
 	help

drivers/net/Makefile

@@ -18,6 +18,7 @@ obj-$(CONFIG_CS8900) += cs8900.o
 obj-$(CONFIG_TULIP) += dc2114x.o
 obj-$(CONFIG_ETH_DESIGNWARE) += designware.o
 obj-$(CONFIG_ETH_DESIGNWARE_SOCFPGA) += dwmac_socfpga.o
+obj-$(CONFIG_ETH_DESIGNWARE_S700) += dwmac_s700.o
 obj-$(CONFIG_DRIVER_DM9000) += dm9000x.o
 obj-$(CONFIG_DNET) += dnet.o
 obj-$(CONFIG_DM_ETH_PHY) += eth-phy-uclass.o

drivers/net/dwmac_s700.c

+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2020 Amit Singh Tomar <amittomer25@gmail.com>
+ *
+ * Actions DWMAC specific glue layer
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <dm.h>
+#include <clk.h>
+#include <phy.h>
+#include <regmap.h>
+#include <reset.h>
+#include <syscon.h>
+#include "designware.h"
+#include <asm/arch-owl/regs_s700.h>
+#include <linux/bitops.h>
+
+/* pin control for MAC */
+#define RMII_TXD01_MFP_CTL0		(0x0 << 16)
+#define RMII_RXD01_MFP_CTL0		(0x0 << 8)
+#define RMII_TXEN_TXER_MFP_CTL0		(0x0 << 13)
+#define RMII_REF_CLK_MFP_CTL0		(0x0 << 6)
+#define CLKO_25M_EN_MFP_CTL3		BIT(30)
+
+DECLARE_GLOBAL_DATA_PTR;
+
+static void dwmac_board_setup(void)
+{
+	clrbits_le32(MFP_CTL0, (RMII_TXD01_MFP_CTL0 | RMII_RXD01_MFP_CTL0 |
+		     RMII_TXEN_TXER_MFP_CTL0 | RMII_REF_CLK_MFP_CTL0));
+
+	setbits_le32(MFP_CTL3, CLKO_25M_EN_MFP_CTL3);
+}
+
+static int dwmac_s700_probe(struct udevice *dev)
+{
+	dwmac_board_setup();
+
+	/* This is undocumented, phy interface select register */
+	writel(0x4, 0xe024c0a0);
+
+	return designware_eth_probe(dev);
+}
+
+static int dwmac_s700_ofdata_to_platdata(struct udevice *dev)
+{
+	return designware_eth_ofdata_to_platdata(dev);
+}
+
+static const struct udevice_id dwmac_s700_ids[] = {
+	{.compatible = "actions,s700-ethernet"},
+	{ }
+};
+
+U_BOOT_DRIVER(dwmac_s700) = {
+	.name   = "dwmac_s700",
+	.id     = UCLASS_ETH,
+	.of_match = dwmac_s700_ids,
+	.ofdata_to_platdata = dwmac_s700_ofdata_to_platdata,
+	.probe  = dwmac_s700_probe,
+	.ops    = &designware_eth_ops,
+	.priv_auto_alloc_size = sizeof(struct dw_eth_dev),
+	.platdata_auto_alloc_size = sizeof(struct eth_pdata),
+	.flags = DM_FLAG_ALLOC_PRIV_DMA,
+};