[v6, PATCH 1/2] net:stmmac: dwmac-mediatek: add support for mt2712

[Biao Huang]

Add Ethernet support for MediaTek SoCs from the mt2712 family

Signed-off-by: Biao Huang <biao.huang@xxxxxxxxxxxx>
---
 drivers/net/ethernet/stmicro/stmmac/Kconfig        |    8 +
 drivers/net/ethernet/stmicro/stmmac/Makefile       |    1 +
 .../net/ethernet/stmicro/stmmac/dwmac-mediatek.c   |  408 ++++++++++++++++++++
 3 files changed, 417 insertions(+)
 create mode 100644 drivers/net/ethernet/stmicro/stmmac/dwmac-mediatek.c

diff --git a/drivers/net/ethernet/stmicro/stmmac/Kconfig b/drivers/net/ethernet/stmicro/stmmac/Kconfig
index 324049e..6209cc1 100644
--- a/drivers/net/ethernet/stmicro/stmmac/Kconfig
+++ b/drivers/net/ethernet/stmicro/stmmac/Kconfig
@@ -75,6 +75,14 @@ config DWMAC_LPC18XX
 	---help---
 	  Support for NXP LPC18xx/43xx DWMAC Ethernet.
 
+config DWMAC_MEDIATEK
+	tristate "MediaTek MT27xx GMAC support"
+	depends on OF && (ARCH_MEDIATEK || COMPILE_TEST)
+	help
+	  Support for MediaTek GMAC Ethernet controller.
+
+	  This selects the MT2712 SoC support for the stmmac driver.
+
 config DWMAC_MESON
 	tristate "Amlogic Meson dwmac support"
 	default ARCH_MESON
diff --git a/drivers/net/ethernet/stmicro/stmmac/Makefile b/drivers/net/ethernet/stmicro/stmmac/Makefile
index 99967a8..bf09701 100644
--- a/drivers/net/ethernet/stmicro/stmmac/Makefile
+++ b/drivers/net/ethernet/stmicro/stmmac/Makefile
@@ -13,6 +13,7 @@ obj-$(CONFIG_STMMAC_PLATFORM)	+= stmmac-platform.o
 obj-$(CONFIG_DWMAC_ANARION)	+= dwmac-anarion.o
 obj-$(CONFIG_DWMAC_IPQ806X)	+= dwmac-ipq806x.o
 obj-$(CONFIG_DWMAC_LPC18XX)	+= dwmac-lpc18xx.o
+obj-$(CONFIG_DWMAC_MEDIATEK)	+= dwmac-mediatek.o
 obj-$(CONFIG_DWMAC_MESON)	+= dwmac-meson.o dwmac-meson8b.o
 obj-$(CONFIG_DWMAC_OXNAS)	+= dwmac-oxnas.o
 obj-$(CONFIG_DWMAC_ROCKCHIP)	+= dwmac-rk.o
diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-mediatek.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-mediatek.c
new file mode 100644
index 0000000..b5db85d
--- /dev/null
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-mediatek.c
@@ -0,0 +1,408 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2018 MediaTek Inc.
+ */
+#include <linux/bitfield.h>
+#include <linux/io.h>
+#include <linux/mfd/syscon.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_net.h>
+#include <linux/regmap.h>
+#include <linux/stmmac.h>
+
+#include "stmmac.h"
+#include "stmmac_platform.h"
+
+/* Peri Configuration register for mt2712 */
+#define PERI_ETH_PHY_INTF_SEL	0x418
+#define PHY_INTF_MII		0
+#define PHY_INTF_RGMII		1
+#define PHY_INTF_RMII		4
+#define RMII_CLK_SRC_RXC	BIT(4)
+#define RMII_CLK_SRC_INTERNAL	BIT(5)
+
+#define PERI_ETH_DLY	0x428
+#define ETH_DLY_GTXC_INV	BIT(6)
+#define ETH_DLY_GTXC_ENABLE	BIT(5)
+#define ETH_DLY_GTXC_STAGES	GENMASK(4, 0)
+#define ETH_DLY_TXC_INV		BIT(20)
+#define ETH_DLY_TXC_ENABLE	BIT(19)
+#define ETH_DLY_TXC_STAGES	GENMASK(18, 14)
+#define ETH_DLY_RXC_INV		BIT(13)
+#define ETH_DLY_RXC_ENABLE	BIT(12)
+#define ETH_DLY_RXC_STAGES	GENMASK(11, 7)
+
+#define PERI_ETH_DLY_FINE	0x800
+#define ETH_RMII_DLY_TX_INV	BIT(2)
+#define ETH_FINE_DLY_GTXC	BIT(1)
+#define ETH_FINE_DLY_RXC	BIT(0)
+
+struct mac_delay_struct {
+	u32 tx_delay;
+	u32 rx_delay;
+	bool tx_inv;
+	bool rx_inv;
+	bool fine_tune;
+};
+
+struct mediatek_dwmac_plat_data {
+	const struct mediatek_dwmac_variant *variant;
+	struct mac_delay_struct mac_delay;
+	struct clk_bulk_data *clks;
+	struct device_node *np;
+	struct regmap *peri_regmap;
+	struct device *dev;
+	int phy_mode;
+	bool rmii_rxc;
+};
+
+struct mediatek_dwmac_variant {
+	int (*dwmac_set_phy_interface)(struct mediatek_dwmac_plat_data *plat);
+	int (*dwmac_set_delay)(struct mediatek_dwmac_plat_data *plat);
+
+	/* clock ids to be requested */
+	const char * const *clk_list;
+	int num_clks;
+
+	u32 dma_bit_mask;
+	u32 rx_delay_max;
+	u32 tx_delay_max;
+};
+
+/* list of clocks required for mac */
+static const char * const mt2712_dwmac_clk_l[] = {
+	"axi", "apb", "mac_main", "ptp_ref"
+};
+
+static int mt2712_set_interface(struct mediatek_dwmac_plat_data *plat)
+{
+	int rmii_rxc = plat->rmii_rxc ? RMII_CLK_SRC_RXC : 0;
+	u32 intf_val = 0;
+
+	/* select phy interface in top control domain */
+	switch (plat->phy_mode) {
+	case PHY_INTERFACE_MODE_MII:
+		intf_val |= PHY_INTF_MII;
+		break;
+	case PHY_INTERFACE_MODE_RMII:
+		intf_val |= (PHY_INTF_RMII | rmii_rxc);
+		break;
+	case PHY_INTERFACE_MODE_RGMII:
+	case PHY_INTERFACE_MODE_RGMII_TXID:
+	case PHY_INTERFACE_MODE_RGMII_RXID:
+	case PHY_INTERFACE_MODE_RGMII_ID:
+		intf_val |= PHY_INTF_RGMII;
+		break;
+	default:
+		dev_err(plat->dev, "phy interface not supported\n");
+		return -EINVAL;
+	}
+
+	regmap_write(plat->peri_regmap, PERI_ETH_PHY_INTF_SEL, intf_val);
+
+	return 0;
+}
+
+static void mt2712_delay_ps2stage(struct mac_delay_struct *mac_delay)
+{
+	if (mac_delay->fine_tune) {
+		/* 170ps per stage for fine tune delay macro circuit*/
+		mac_delay->tx_delay /= 170;
+		mac_delay->rx_delay /= 170;
+	} else {
+		/* 550ps per stage for coarse tune delay macro circuit*/
+		mac_delay->tx_delay /= 550;
+		mac_delay->rx_delay /= 550;
+	}
+}
+
+static int mt2712_set_delay(struct mediatek_dwmac_plat_data *plat)
+{
+	struct mac_delay_struct *mac_delay = &plat->mac_delay;
+	u32 delay_val = 0, fine_val = 0;
+
+	mt2712_delay_ps2stage(mac_delay);
+
+	switch (plat->phy_mode) {
+	case PHY_INTERFACE_MODE_MII:
+		delay_val |= FIELD_PREP(ETH_DLY_TXC_ENABLE, !!mac_delay->tx_delay);
+		delay_val |= FIELD_PREP(ETH_DLY_TXC_STAGES, mac_delay->tx_delay);
+		delay_val |= FIELD_PREP(ETH_DLY_TXC_INV, mac_delay->tx_inv);
+
+		delay_val |= FIELD_PREP(ETH_DLY_RXC_ENABLE, !!mac_delay->rx_delay);
+		delay_val |= FIELD_PREP(ETH_DLY_RXC_STAGES, mac_delay->rx_delay);
+		delay_val |= FIELD_PREP(ETH_DLY_RXC_INV, mac_delay->rx_inv);
+		break;
+	case PHY_INTERFACE_MODE_RMII:
+		/* the rmii reference clock is from external phy,
+		 * and the property "rmii_rxc" indicates which pin(TXC/RXC)
+		 * the reference clk is connected to. The reference clock is a
+		 * received signal, so rx_delay/rx_inv are used to indicate
+		 * the reference clock timing adjustment
+		 */
+		if (plat->rmii_rxc) {
+			/* the rmii reference clock from outside is connected
+			 * to RXC pin, the reference clock will be adjusted
+			 * by RXC delay macro circuit.
+			 */
+			delay_val |= FIELD_PREP(ETH_DLY_RXC_ENABLE, !!mac_delay->rx_delay);
+			delay_val |= FIELD_PREP(ETH_DLY_RXC_STAGES, mac_delay->rx_delay);
+			delay_val |= FIELD_PREP(ETH_DLY_RXC_INV, mac_delay->rx_inv);
+		} else {
+			/* the rmii reference clock from outside is connected
+			 * to TXC pin, the reference clock will be adjusted
+			 * by TXC delay macro circuit.
+			 */
+			delay_val |= FIELD_PREP(ETH_DLY_TXC_ENABLE, !!mac_delay->rx_delay);
+			delay_val |= FIELD_PREP(ETH_DLY_TXC_STAGES, mac_delay->rx_delay);
+			delay_val |= FIELD_PREP(ETH_DLY_TXC_INV, mac_delay->rx_inv);
+		}
+		/* tx_inv will inverse the tx clock inside mac relateive to
+		 * reference clock from external phy,
+		 * and this bit is located in the same register with fine-tune
+		 */
+		if (mac_delay->tx_inv)
+			fine_val = ETH_RMII_DLY_TX_INV;
+		break;
+	case PHY_INTERFACE_MODE_RGMII:
+		/* the PHY is not responsible for inserting any internal
+		 * delay by itself in PHY_INTERFACE_MODE_RGMII case,
+		 * so Ethernet MAC will insert delays for both transmit
+		 * and receive path here.
+		 */
+		if (mac_delay->fine_tune)
+			fine_val = ETH_FINE_DLY_GTXC | ETH_FINE_DLY_RXC;
+
+		delay_val |= FIELD_PREP(ETH_DLY_GTXC_ENABLE, !!mac_delay->tx_delay);
+		delay_val |= FIELD_PREP(ETH_DLY_GTXC_STAGES, mac_delay->tx_delay);
+		delay_val |= FIELD_PREP(ETH_DLY_GTXC_INV, mac_delay->tx_inv);
+
+		delay_val |= FIELD_PREP(ETH_DLY_RXC_ENABLE, !!mac_delay->rx_delay);
+		delay_val |= FIELD_PREP(ETH_DLY_RXC_STAGES, mac_delay->rx_delay);
+		delay_val |= FIELD_PREP(ETH_DLY_RXC_INV, mac_delay->rx_inv);
+		break;
+	case PHY_INTERFACE_MODE_RGMII_TXID:
+		/* the PHY should insert an internal delay for the transmit
+		 * path in PHY_INTERFACE_MODE_RGMII_TXID case,
+		 * so Ethernet MAC will insert the delay for receive path here.
+		 */
+		if (mac_delay->fine_tune)
+			fine_val = ETH_FINE_DLY_RXC;
+
+		delay_val |= FIELD_PREP(ETH_DLY_RXC_ENABLE, !!mac_delay->rx_delay);
+		delay_val |= FIELD_PREP(ETH_DLY_RXC_STAGES, mac_delay->rx_delay);
+		delay_val |= FIELD_PREP(ETH_DLY_RXC_INV, mac_delay->rx_inv);
+		break;
+	case PHY_INTERFACE_MODE_RGMII_RXID:
+		/* the PHY should insert an internal delay for the receive
+		 * path in PHY_INTERFACE_MODE_RGMII_RXID case,
+		 * so Ethernet MAC will insert the delay for transmit path here.
+		 */
+		if (mac_delay->fine_tune)
+			fine_val = ETH_FINE_DLY_GTXC;
+
+		delay_val |= FIELD_PREP(ETH_DLY_GTXC_ENABLE, !!mac_delay->tx_delay);
+		delay_val |= FIELD_PREP(ETH_DLY_GTXC_STAGES, mac_delay->tx_delay);
+		delay_val |= FIELD_PREP(ETH_DLY_GTXC_INV, mac_delay->tx_inv);
+		break;
+	case PHY_INTERFACE_MODE_RGMII_ID:
+		/* the PHY should insert internal delays for both transmit
+		 * and receive path in PHY_INTERFACE_MODE_RGMII_RXID case,
+		 * so Ethernet MAC will NOT insert any delay here.
+		 */
+		break;
+	default:
+		dev_err(plat->dev, "phy interface not supported\n");
+		return -EINVAL;
+	}
+	regmap_write(plat->peri_regmap, PERI_ETH_DLY, delay_val);
+	regmap_write(plat->peri_regmap, PERI_ETH_DLY_FINE, fine_val);
+
+	return 0;
+}
+
+static const struct mediatek_dwmac_variant mt2712_gmac_variant = {
+		.dwmac_set_phy_interface = mt2712_set_interface,
+		.dwmac_set_delay = mt2712_set_delay,
+		.clk_list = mt2712_dwmac_clk_l,
+		.num_clks = ARRAY_SIZE(mt2712_dwmac_clk_l),
+		.dma_bit_mask = 33,
+		.rx_delay_max = 17600,
+		.tx_delay_max = 17600,
+};
+
+static int mediatek_dwmac_config_dt(struct mediatek_dwmac_plat_data *plat)
+{
+	struct mac_delay_struct *mac_delay = &plat->mac_delay;
+	u32 tx_delay_ps, rx_delay_ps;
+
+	plat->peri_regmap = syscon_regmap_lookup_by_phandle(plat->np, "mediatek,pericfg");
+	if (IS_ERR(plat->peri_regmap)) {
+		dev_err(plat->dev, "Failed to get pericfg syscon\n");
+		return PTR_ERR(plat->peri_regmap);
+	}
+
+	plat->phy_mode = of_get_phy_mode(plat->np);
+	if (plat->phy_mode < 0) {
+		dev_err(plat->dev, "not find phy-mode\n");
+		return -EINVAL;
+	}
+
+	if (!of_property_read_u32(plat->np, "mediatek,tx-delay-ps", &tx_delay_ps)) {
+		if (tx_delay_ps < plat->variant->tx_delay_max) {
+			mac_delay->tx_delay = tx_delay_ps;
+		} else {
+			dev_err(plat->dev, "Invalid TX clock delay: %dps\n", tx_delay_ps);
+			return -EINVAL;
+		}
+	}
+
+	if (!of_property_read_u32(plat->np, "mediatek,rx-delay-ps", &rx_delay_ps)) {
+		if (rx_delay_ps < plat->variant->rx_delay_max) {
+			mac_delay->rx_delay = rx_delay_ps;
+		} else {
+			dev_err(plat->dev, "Invalid RX clock delay: %dps\n", rx_delay_ps);
+			return -EINVAL;
+		}
+	}
+
+	mac_delay->tx_inv = of_property_read_bool(plat->np, "mediatek,txc-inverse");
+	mac_delay->rx_inv = of_property_read_bool(plat->np, "mediatek,rxc-inverse");
+	mac_delay->fine_tune = of_property_read_bool(plat->np, "mediatek,fine-tune");
+	plat->rmii_rxc = of_property_read_bool(plat->np, "mediatek,rmii-rxc");
+
+	return 0;
+}
+
+static int mediatek_dwmac_clk_init(struct mediatek_dwmac_plat_data *plat)
+{
+	const struct mediatek_dwmac_variant *variant = plat->variant;
+	int i, num = variant->num_clks;
+
+	plat->clks = devm_kcalloc(plat->dev, num, sizeof(*plat->clks), GFP_KERNEL);
+	if (!plat->clks)
+		return -ENOMEM;
+
+	for (i = 0; i < num; i++)
+		plat->clks[i].id = variant->clk_list[i];
+
+	return devm_clk_bulk_get(plat->dev, num, plat->clks);
+}
+
+static int mediatek_dwmac_init(struct platform_device *pdev, void *priv)
+{
+	struct mediatek_dwmac_plat_data *plat = priv;
+	const struct mediatek_dwmac_variant *variant = plat->variant;
+	int ret;
+
+	ret = dma_set_mask_and_coherent(plat->dev, DMA_BIT_MASK(variant->dma_bit_mask));
+	if (ret) {
+		dev_err(plat->dev, "No suitable DMA available, err = %d\n", ret);
+		return ret;
+	}
+
+	ret = variant->dwmac_set_phy_interface(plat);
+	if (ret) {
+		dev_err(plat->dev, "failed to set phy interface, err = %d\n", ret);
+		return ret;
+	}
+
+	ret = variant->dwmac_set_delay(plat);
+	if (ret) {
+		dev_err(plat->dev, "failed to set delay value, err = %d\n", ret);
+		return ret;
+	}
+
+	ret = clk_bulk_prepare_enable(variant->num_clks, plat->clks);
+	if (ret) {
+		dev_err(plat->dev, "failed to enable clks, err = %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static void mediatek_dwmac_exit(struct platform_device *pdev, void *priv)
+{
+	struct mediatek_dwmac_plat_data *plat = priv;
+	const struct mediatek_dwmac_variant *variant = plat->variant;
+
+	clk_bulk_disable_unprepare(variant->num_clks, plat->clks);
+}
+
+static int mediatek_dwmac_probe(struct platform_device *pdev)
+{
+	struct mediatek_dwmac_plat_data *priv_plat;
+	struct plat_stmmacenet_data *plat_dat;
+	struct stmmac_resources stmmac_res;
+	int ret;
+
+	priv_plat = devm_kzalloc(&pdev->dev, sizeof(*priv_plat), GFP_KERNEL);
+	if (!priv_plat)
+		return -ENOMEM;
+
+	priv_plat->variant = of_device_get_match_data(&pdev->dev);
+	if (!priv_plat->variant) {
+		dev_err(&pdev->dev, "Missing dwmac-mediatek variant\n");
+		return -EINVAL;
+	}
+
+	priv_plat->dev = &pdev->dev;
+	priv_plat->np = pdev->dev.of_node;
+
+	ret = mediatek_dwmac_config_dt(priv_plat);
+	if (ret)
+		return ret;
+
+	ret = mediatek_dwmac_clk_init(priv_plat);
+	if (ret)
+		return ret;
+
+	ret = stmmac_get_platform_resources(pdev, &stmmac_res);
+	if (ret)
+		return ret;
+
+	plat_dat = stmmac_probe_config_dt(pdev, &stmmac_res.mac);
+	if (IS_ERR(plat_dat))
+		return PTR_ERR(plat_dat);
+
+	plat_dat->interface = priv_plat->phy_mode;
+	/* clk_csr_i = 250-300MHz & MDC = clk_csr_i/124 */
+	plat_dat->clk_csr = 5;
+	plat_dat->has_gmac4 = 1;
+	plat_dat->has_gmac = 0;
+	plat_dat->pmt = 0;
+	plat_dat->maxmtu = ETH_DATA_LEN;
+	plat_dat->bsp_priv = priv_plat;
+	plat_dat->init = mediatek_dwmac_init;
+	plat_dat->exit = mediatek_dwmac_exit;
+	mediatek_dwmac_init(pdev, priv_plat);
+
+	ret = stmmac_dvr_probe(&pdev->dev, plat_dat, &stmmac_res);
+	if (ret) {
+		stmmac_remove_config_dt(pdev, plat_dat);
+		return ret;
+	}
+
+	return 0;
+}
+
+static const struct of_device_id mediatek_dwmac_match[] = {
+	{ .compatible = "mediatek,mt2712-gmac",
+	  .data = &mt2712_gmac_variant },
+	{ }
+};
+
+MODULE_DEVICE_TABLE(of, mediatek_dwmac_match);
+
+static struct platform_driver mediatek_dwmac_driver = {
+	.probe  = mediatek_dwmac_probe,
+	.remove = stmmac_pltfr_remove,
+	.driver = {
+		.name           = "dwmac-mediatek",
+		.pm		= &stmmac_pltfr_pm_ops,
+		.of_match_table = mediatek_dwmac_match,
+	},
+};
+module_platform_driver(mediatek_dwmac_driver);
-- 
1.7.9.5