net: phy: mediatek: add driver for built-in 2.5G ethernet PHY on MT7988

Add support for internal 2.5Gphy on MT7988. This driver will load
necessary firmware and add appropriate time delay to make sure
that firmware works stably. The firmware loading procedure takes
about 11ms in this driver.

Signed-off-by: Sky Huang <[e-mail]>
Reviewed-by: Andrew Lunn <[e-mail]>
Link: https://patch.msgid.link/[e-mail]
Signed-off-by: Jakub Kicinski <[e-mail]>

MAINTAINERS

···
 M:	SkyLake Huang <[e-mail]>
 L:	[e-mail]
 S:	Maintained
+F:	drivers/net/phy/mediatek/mtk-2p5ge.c
 F:	drivers/net/phy/mediatek/mtk-ge-soc.c
 F:	drivers/net/phy/mediatek/mtk-phy-lib.c
 F:	drivers/net/phy/mediatek/mtk-ge.c

drivers/net/phy/mediatek/Kconfig

···
 # SPDX-License-Identifier: GPL-2.0-only
+config MEDIATEK_2P5GE_PHY
+	tristate "MediaTek 2.5Gb Ethernet PHYs"
+	depends on (ARM64 && ARCH_MEDIATEK) || COMPILE_TEST
+	select MTK_NET_PHYLIB
+	help
+	  Supports MediaTek SoC built-in 2.5Gb Ethernet PHYs.
+
+	  This will load necessary firmware and add appropriate time delay.
+	  Accelerate this procedure through internal pbus instead of MDIO
+	  bus. Certain link-up issues will also be fixed here.
+
 config MEDIATEK_GE_PHY
 	tristate "MediaTek Gigabit Ethernet PHYs"
 	select MTK_NET_PHYLIB

drivers/net/phy/mediatek/Makefile

···
 # SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_MEDIATEK_2P5GE_PHY)	+= mtk-2p5ge.o
 obj-$(CONFIG_MEDIATEK_GE_PHY)		+= mtk-ge.o
 obj-$(CONFIG_MEDIATEK_GE_SOC_PHY)	+= mtk-ge-soc.o
 obj-$(CONFIG_MTK_NET_PHYLIB)		+= mtk-phy-lib.o

drivers/net/phy/mediatek/mtk-2p5ge.c

···
+// SPDX-License-Identifier: GPL-2.0+
+#include <linux/bitfield.h>
+#include <linux/firmware.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_platform.h>
+#include <linux/pinctrl/consumer.h>
+#include <linux/phy.h>
+
+#include "mtk.h"
+
+#define MTK_2P5GPHY_ID_MT7988		0x00339c11
+
+#define MT7988_2P5GE_PMB_FW		"mediatek/mt7988/i2p5ge-phy-pmb.bin"
+#define MT7988_2P5GE_PMB_FW_SIZE	0x20000
+#define MT7988_2P5GE_PMB_FW_BASE	0x0f100000
+#define MT7988_2P5GE_PMB_FW_LEN		0x20000
+#define MTK_2P5GPHY_MCU_CSR_BASE	0x0f0f0000
+#define MTK_2P5GPHY_MCU_CSR_LEN		0x20
+#define MD32_EN_CFG			0x18
+#define   MD32_EN			BIT(0)
+
+#define BASE100T_STATUS_EXTEND		0x10
+#define BASE1000T_STATUS_EXTEND		0x11
+#define EXTEND_CTRL_AND_STATUS		0x16
+
+#define PHY_AUX_CTRL_STATUS		0x1d
+#define   PHY_AUX_DPX_MASK		GENMASK(5, 5)
+#define   PHY_AUX_SPEED_MASK		GENMASK(4, 2)
+
+/* Registers on MDIO_MMD_VEND1 */
+#define MTK_PHY_LPI_PCS_DSP_CTRL		0x121
+#define   MTK_PHY_LPI_SIG_EN_LO_THRESH100_MASK	GENMASK(12, 8)
+
+#define MTK_PHY_HOST_CMD1		0x800e
+#define MTK_PHY_HOST_CMD2		0x800f
+/* Registers on Token Ring debug nodes */
+/* ch_addr = 0x0, node_addr = 0xf, data_addr = 0x3c */
+#define AUTO_NP_10XEN				BIT(6)
+
+enum {
+	PHY_AUX_SPD_10 = 0,
+	PHY_AUX_SPD_100,
+	PHY_AUX_SPD_1000,
+	PHY_AUX_SPD_2500,
+};
+
+static int mt798x_2p5ge_phy_load_fw(struct phy_device *phydev)
+{
+	struct device *dev = &phydev->mdio.dev;
+	void __iomem *mcu_csr_base, *pmb_addr;
+	const struct firmware *fw;
+	int ret, i;
+	u32 reg;
+
+	pmb_addr = ioremap(MT7988_2P5GE_PMB_FW_BASE, MT7988_2P5GE_PMB_FW_LEN);
+	if (!pmb_addr)
+		return -ENOMEM;
+	mcu_csr_base = ioremap(MTK_2P5GPHY_MCU_CSR_BASE,
+			       MTK_2P5GPHY_MCU_CSR_LEN);
+	if (!mcu_csr_base) {
+		ret = -ENOMEM;
+		goto free_pmb;
+	}
+
+	ret = request_firmware_direct(&fw, MT7988_2P5GE_PMB_FW, dev);
+	if (ret) {
+		dev_err(dev, "failed to load firmware: %s, ret: %d\n",
+			MT7988_2P5GE_PMB_FW, ret);
+		goto free;
+	}
+
+	if (fw->size != MT7988_2P5GE_PMB_FW_SIZE) {
+		dev_err(dev, "Firmware size 0x%zx != 0x%x\n",
+			fw->size, MT7988_2P5GE_PMB_FW_SIZE);
+		ret = -EINVAL;
+		goto release_fw;
+	}
+
+	reg = readw(mcu_csr_base + MD32_EN_CFG);
+	if (reg & MD32_EN) {
+		phy_set_bits(phydev, MII_BMCR, BMCR_RESET);
+		usleep_range(10000, 11000);
+	}
+	phy_set_bits(phydev, MII_BMCR, BMCR_PDOWN);
+
+	/* Write magic number to safely stall MCU */
+	phy_write_mmd(phydev, MDIO_MMD_VEND1, MTK_PHY_HOST_CMD1, 0x1100);
+	phy_write_mmd(phydev, MDIO_MMD_VEND1, MTK_PHY_HOST_CMD2, 0x00df);
+
+	for (i = 0; i < MT7988_2P5GE_PMB_FW_SIZE - 1; i += 4)
+		writel(*((uint32_t *)(fw->data + i)), pmb_addr + i);
+
+	writew(reg & ~MD32_EN, mcu_csr_base + MD32_EN_CFG);
+	writew(reg | MD32_EN, mcu_csr_base + MD32_EN_CFG);
+	phy_set_bits(phydev, MII_BMCR, BMCR_RESET);
+	/* We need a delay here to stabilize initialization of MCU */
+	usleep_range(7000, 8000);
+
+	dev_info(dev, "Firmware date code: %x/%x/%x, version: %x.%x\n",
+		 be16_to_cpu(*((__be16 *)(fw->data +
+					  MT7988_2P5GE_PMB_FW_SIZE - 8))),
+		 *(fw->data + MT7988_2P5GE_PMB_FW_SIZE - 6),
+		 *(fw->data + MT7988_2P5GE_PMB_FW_SIZE - 5),
+		 *(fw->data + MT7988_2P5GE_PMB_FW_SIZE - 2),
+		 *(fw->data + MT7988_2P5GE_PMB_FW_SIZE - 1));
+
+release_fw:
+	release_firmware(fw);
+free:
+	iounmap(mcu_csr_base);
+free_pmb:
+	iounmap(pmb_addr);
+
+	return ret;
+}
+
+static int mt798x_2p5ge_phy_config_init(struct phy_device *phydev)
+{
+	/* Check if PHY interface type is compatible */
+	if (phydev->interface != PHY_INTERFACE_MODE_INTERNAL)
+		return -ENODEV;
+
+	phy_modify_mmd(phydev, MDIO_MMD_VEND1, MTK_PHY_LPI_PCS_DSP_CTRL,
+		       MTK_PHY_LPI_SIG_EN_LO_THRESH100_MASK, 0);
+
+	/* Enable 16-bit next page exchange bit if 1000-BT isn't advertising */
+	mtk_tr_modify(phydev, 0x0, 0xf, 0x3c, AUTO_NP_10XEN,
+		      FIELD_PREP(AUTO_NP_10XEN, 0x1));
+
+	/* Enable HW auto downshift */
+	phy_modify_paged(phydev, MTK_PHY_PAGE_EXTENDED_1,
+			 MTK_PHY_AUX_CTRL_AND_STATUS,
+			 0, MTK_PHY_ENABLE_DOWNSHIFT);
+
+	return 0;
+}
+
+static int mt798x_2p5ge_phy_config_aneg(struct phy_device *phydev)
+{
+	bool changed = false;
+	u32 adv;
+	int ret;
+
+	ret = genphy_c45_an_config_aneg(phydev);
+	if (ret < 0)
+		return ret;
+	if (ret > 0)
+		changed = true;
+
+	/* Clause 45 doesn't define 1000BaseT support. Use Clause 22 instead in
+	 * our design.
+	 */
+	adv = linkmode_adv_to_mii_ctrl1000_t(phydev->advertising);
+	ret = phy_modify_changed(phydev, MII_CTRL1000, ADVERTISE_1000FULL, adv);
+	if (ret < 0)
+		return ret;
+	if (ret > 0)
+		changed = true;
+
+	return genphy_c45_check_and_restart_aneg(phydev, changed);
+}
+
+static int mt798x_2p5ge_phy_get_features(struct phy_device *phydev)
+{
+	int ret;
+
+	ret = genphy_c45_pma_read_abilities(phydev);
+	if (ret)
+		return ret;
+
+	/* This phy can't handle collision, and neither can (XFI)MAC it's
+	 * connected to. Although it can do HDX handshake, it doesn't support
+	 * CSMA/CD that HDX requires.
+	 */
+	linkmode_clear_bit(ETHTOOL_LINK_MODE_100baseT_Half_BIT,
+			   phydev->supported);
+
+	return 0;
+}
+
+static int mt798x_2p5ge_phy_read_status(struct phy_device *phydev)
+{
+	int ret;
+
+	/* When MDIO_STAT1_LSTATUS is raised genphy_c45_read_link(), this phy
+	 * actually hasn't finished AN. So use CL22's link update function
+	 * instead.
+	 */
+	ret = genphy_update_link(phydev);
+	if (ret)
+		return ret;
+
+	phydev->speed = SPEED_UNKNOWN;
+	phydev->duplex = DUPLEX_UNKNOWN;
+	phydev->pause = 0;
+	phydev->asym_pause = 0;
+
+	/* We'll read link speed through vendor specific registers down below.
+	 * So remove phy_resolve_aneg_linkmode (AN on) & genphy_c45_read_pma
+	 * (AN off).
+	 */
+	if (phydev->autoneg == AUTONEG_ENABLE && phydev->autoneg_complete) {
+		ret = genphy_c45_read_lpa(phydev);
+		if (ret < 0)
+			return ret;
+
+		/* Clause 45 doesn't define 1000BaseT support. Read the link
+		 * partner's 1G advertisement via Clause 22.
+		 */
+		ret = phy_read(phydev, MII_STAT1000);
+		if (ret < 0)
+			return ret;
+		mii_stat1000_mod_linkmode_lpa_t(phydev->lp_advertising, ret);
+	} else if (phydev->autoneg == AUTONEG_DISABLE) {
+		linkmode_zero(phydev->lp_advertising);
+	}
+
+	if (phydev->link) {
+		ret = phy_read(phydev, PHY_AUX_CTRL_STATUS);
+		if (ret < 0)
+			return ret;
+
+		switch (FIELD_GET(PHY_AUX_SPEED_MASK, ret)) {
+		case PHY_AUX_SPD_10:
+			phydev->speed = SPEED_10;
+			break;
+		case PHY_AUX_SPD_100:
+			phydev->speed = SPEED_100;
+			break;
+		case PHY_AUX_SPD_1000:
+			phydev->speed = SPEED_1000;
+			break;
+		case PHY_AUX_SPD_2500:
+			phydev->speed = SPEED_2500;
+			break;
+		}
+
+		phydev->duplex = DUPLEX_FULL;
+		phydev->rate_matching = RATE_MATCH_PAUSE;
+	}
+
+	return 0;
+}
+
+static int mt798x_2p5ge_phy_get_rate_matching(struct phy_device *phydev,
+					      phy_interface_t iface)
+{
+	return RATE_MATCH_PAUSE;
+}
+
+static int mt798x_2p5ge_phy_probe(struct phy_device *phydev)
+{
+	struct pinctrl *pinctrl;
+	int ret;
+
+	switch (phydev->drv->phy_id) {
+	case MTK_2P5GPHY_ID_MT7988:
+		/* This built-in 2.5GbE hardware only sets MDIO_DEVS_PMAPMD.
+		 * Set the rest by this driver since PCS/AN/VEND1/VEND2 MDIO
+		 * manageable devices actually exist.
+		 */
+		phydev->c45_ids.mmds_present |= MDIO_DEVS_PCS |
+						MDIO_DEVS_AN |
+						MDIO_DEVS_VEND1 |
+						MDIO_DEVS_VEND2;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	ret = mt798x_2p5ge_phy_load_fw(phydev);
+	if (ret < 0)
+		return ret;
+
+	/* Setup LED */
+	phy_set_bits_mmd(phydev, MDIO_MMD_VEND2, MTK_PHY_LED0_ON_CTRL,
+			 MTK_PHY_LED_ON_POLARITY | MTK_PHY_LED_ON_LINK10 |
+			 MTK_PHY_LED_ON_LINK100 | MTK_PHY_LED_ON_LINK1000 |
+			 MTK_PHY_LED_ON_LINK2500);
+	phy_set_bits_mmd(phydev, MDIO_MMD_VEND2, MTK_PHY_LED1_ON_CTRL,
+			 MTK_PHY_LED_ON_FDX | MTK_PHY_LED_ON_HDX);
+
+	/* Switch pinctrl after setting polarity to avoid bogus blinking */
+	pinctrl = devm_pinctrl_get_select(&phydev->mdio.dev, "i2p5gbe-led");
+	if (IS_ERR(pinctrl))
+		dev_err(&phydev->mdio.dev, "Fail to set LED pins!\n");
+
+	return 0;
+}
+
+static struct phy_driver mtk_2p5gephy_driver[] = {
+	{
+		PHY_ID_MATCH_MODEL(MTK_2P5GPHY_ID_MT7988),
+		.name = "MediaTek MT7988 2.5GbE PHY",
+		.probe = mt798x_2p5ge_phy_probe,
+		.config_init = mt798x_2p5ge_phy_config_init,
+		.config_aneg = mt798x_2p5ge_phy_config_aneg,
+		.get_features = mt798x_2p5ge_phy_get_features,
+		.read_status = mt798x_2p5ge_phy_read_status,
+		.get_rate_matching = mt798x_2p5ge_phy_get_rate_matching,
+		.suspend = genphy_suspend,
+		.resume = genphy_resume,
+		.read_page = mtk_phy_read_page,
+		.write_page = mtk_phy_write_page,
+	},
+};
+
+module_phy_driver(mtk_2p5gephy_driver);
+
+static struct mdio_device_id __maybe_unused mtk_2p5ge_phy_tbl[] = {
+	{ PHY_ID_MATCH_VENDOR(0x00339c00) },
+	{ }
+};
+
+MODULE_DESCRIPTION("MediaTek 2.5Gb Ethernet PHY driver");
+MODULE_AUTHOR("SkyLake Huang <[e-mail]>");
+MODULE_LICENSE("GPL");
+
+MODULE_DEVICE_TABLE(mdio, mtk_2p5ge_phy_tbl);
+MODULE_FIRMWARE(MT7988_2P5GE_PMB_FW);