[PATCH net-next v6 5/5] net: phy: add driver for built-in 2.5G ethernet PHY on MT7988

[Sky Huang]

From: "SkyLake.Huang" <skylake.huang@xxxxxxxxxxxx>

Add support for internal 2.5Gphy on MT7988. This driver will load
necessary firmware, add appropriate time delay and figure out LED.
Also, certain control registers will be set to fix link-up issues.

Signed-off-by: SkyLake.Huang <skylake.huang@xxxxxxxxxxxx>
---
Changes in v2:
1. Move md32_en_cfg_base & pmb_addr detection in probe function.
2. Do not read PMB & MD32_EN_CFG base addresses from dts. We won't
change that from board to board. Leave them in driver code. Also,
release those addresses after firmware is triggered.
3. Remove half duplex code which leads to ambiguity. Those are for
testing & developing previously.
4. Use correct BMCR definitions.
5. Correct config_aneg / get_features / read_status functions.
6. Change mt7988_2p5ge prefix to mt798x_2p5ge in case that our next
platform uses this 2.5Gphy driver.

Changes in v3:
1. Add range check for firmware.
2. Fix c45_ids.mmds_present in probe function.
3. Still use genphy_update_link() in read_status because
genphy_c45_read_link() can't correct detect link on this phy.

Changes in v4:
1. Move firmware loading function to mt798x_2p5ge_phy_load_fw()
2. Add AN disable warning in mt798x_2p5ge_phy_config_aneg()
3. Clarify the HDX comments in mt798x_2p5ge_phy_get_features()

Changes in v5:
1. Move md32_en_cfg_base & pmb_addr to local variables to achieve
symmetric code.
2. Print out firmware date code & version.
3. Don't return error if LED pinctrl switching fails. Also, add
comments to this unusual operations.
4. Return -EOPNOTSUPP for AN off case in config_aneg().

Changes in v6:
1. Force casting (fw->data + MT7988_2P5GE_PMB_SIZE - 8) with __be16.
2. Remove parens on RHS of "phydev->c45_ids.mmds_present |=".
3. Add PHY_INTERFACE_MODE_INTERNAL check in
mt798x_2p5ge_phy_get_rate_matching()
4. Arrange local variables in reverse Xmas tree order.
---
 MAINTAINERS                          |   1 +
 drivers/net/phy/mediatek/Kconfig     |  11 +
 drivers/net/phy/mediatek/Makefile    |   1 +
 drivers/net/phy/mediatek/mtk-2p5ge.c | 435 +++++++++++++++++++++++++++
 4 files changed, 448 insertions(+)
 create mode 100644 drivers/net/phy/mediatek/mtk-2p5ge.c

diff --git a/MAINTAINERS b/MAINTAINERS
index e58e05c..fe380f2 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -13793,6 +13793,7 @@ M:	Qingfang Deng <dqfext@xxxxxxxxx>
 M:	SkyLake Huang <SkyLake.Huang@xxxxxxxxxxxx>
 L:	netdev@xxxxxxxxxxxxxxx
 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
diff --git a/drivers/net/phy/mediatek/Kconfig b/drivers/net/phy/mediatek/Kconfig
index 448bc20..1490352 100644
--- a/drivers/net/phy/mediatek/Kconfig
+++ b/drivers/net/phy/mediatek/Kconfig
@@ -25,3 +25,14 @@ config MEDIATEK_GE_SOC_PHY
 	  the MT7981 and MT7988 SoCs. These PHYs need calibration data
 	  present in the SoCs efuse and will dynamically calibrate VCM
 	  (common-mode voltage) during startup.
+
+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.
diff --git a/drivers/net/phy/mediatek/Makefile b/drivers/net/phy/mediatek/Makefile
index 814879d..c6db8ab 100644
--- a/drivers/net/phy/mediatek/Makefile
+++ b/drivers/net/phy/mediatek/Makefile
@@ -2,3 +2,4 @@
 obj-$(CONFIG_MTK_NET_PHYLIB)		+= mtk-phy-lib.o
 obj-$(CONFIG_MEDIATEK_GE_PHY)		+= mtk-ge.o
 obj-$(CONFIG_MEDIATEK_GE_SOC_PHY)	+= mtk-ge-soc.o
+obj-$(CONFIG_MEDIATEK_2P5GE_PHY)	+= mtk-2p5ge.o
diff --git a/drivers/net/phy/mediatek/mtk-2p5ge.c b/drivers/net/phy/mediatek/mtk-2p5ge.c
new file mode 100644
index 0000000..0c92608
--- /dev/null
+++ b/drivers/net/phy/mediatek/mtk-2p5ge.c
@@ -0,0 +1,435 @@
+// SPDX-License-Identifier: GPL-2.0+
+#include <linux/bitfield.h>
+#include <linux/firmware.h>
+#include <linux/module.h>
+#include <linux/nvmem-consumer.h>
+#include <linux/of_address.h>
+#include <linux/of_platform.h>
+#include <linux/pinctrl/consumer.h>
+#include <linux/phy.h>
+#include <linux/pm_domain.h>
+#include <linux/pm_runtime.h>
+
+#include "mtk.h"
+
+#define MTK_2P5GPHY_ID_MT7988	(0x00339c11)
+
+#define MT7988_2P5GE_PMB "mediatek/mt7988/i2p5ge-phy-pmb.bin"
+#define MT7988_2P5GE_PMB_SIZE	(0x20000)
+#define MT7988_2P5GE_PMB_BASE	(0x0f100000)
+#define MT7988_2P5GE_PMB_LEN	(0x20000)
+#define MT7988_2P5GE_MD32_EN_CFG_BASE	(0x0f0f0018)
+#define MT7988_2P5GE_MD32_EN_CFG_LEN	(0x20)
+#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)
+
+#define MTK_PHY_LPI_PCS_DSP_CTRL		(0x121)
+#define   MTK_PHY_LPI_SIG_EN_LO_THRESH100_MASK	GENMASK(12, 8)
+
+/* Registers on Token Ring debug nodes */
+/* ch_addr = 0x0, node_addr = 0xf, data_addr = 0x3c */
+#define AUTO_NP_10XEN				BIT(6)
+
+struct mtk_i2p5ge_phy_priv {
+	bool fw_loaded;
+	unsigned long led_state;
+};
+
+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 mtk_i2p5ge_phy_priv *priv = phydev->priv;
+	void __iomem *md32_en_cfg_base, *pmb_addr;
+	struct device *dev = &phydev->mdio.dev;
+	const struct firmware *fw;
+	int ret, i;
+	u16 reg;
+
+	if (priv->fw_loaded)
+		return 0;
+
+	pmb_addr = ioremap(MT7988_2P5GE_PMB_BASE, MT7988_2P5GE_PMB_LEN);
+	if (!pmb_addr)
+		return -ENOMEM;
+	md32_en_cfg_base = ioremap(MT7988_2P5GE_MD32_EN_CFG_BASE,
+				   MT7988_2P5GE_MD32_EN_CFG_LEN);
+	if (!md32_en_cfg_base) {
+		ret = -ENOMEM;
+		goto free_pmb;
+	}
+
+	ret = request_firmware(&fw, MT7988_2P5GE_PMB, dev);
+	if (ret) {
+		dev_err(dev, "failed to load firmware: %s, ret: %d\n",
+			MT7988_2P5GE_PMB, ret);
+		goto free;
+	}
+
+	if (fw->size != MT7988_2P5GE_PMB_SIZE) {
+		dev_err(dev, "Firmware size 0x%zx != 0x%x\n",
+			fw->size, MT7988_2P5GE_PMB_SIZE);
+		ret = -EINVAL;
+		goto free;
+	}
+
+	reg = readw(md32_en_cfg_base);
+	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, 0x800e, 0x1100);
+	phy_write_mmd(phydev, MDIO_MMD_VEND1, 0x800f, 0x00df);
+
+	for (i = 0; i < MT7988_2P5GE_PMB_SIZE - 1; i += 4)
+		writel(*((uint32_t *)(fw->data + i)), pmb_addr + i);
+	release_firmware(fw);
+	dev_info(dev, "Firmware date code: %x/%x/%x, version: %x.%x\n",
+		 be16_to_cpu(*((__be16 *)(fw->data +
+					  MT7988_2P5GE_PMB_SIZE - 8))),
+		 *(fw->data + MT7988_2P5GE_PMB_SIZE - 6),
+		 *(fw->data + MT7988_2P5GE_PMB_SIZE - 5),
+		 *(fw->data + MT7988_2P5GE_PMB_SIZE - 2),
+		 *(fw->data + MT7988_2P5GE_PMB_SIZE - 1));
+
+	writew(reg & ~MD32_EN, md32_en_cfg_base);
+	writew(reg | MD32_EN, md32_en_cfg_base);
+	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 loading/trigger ok.\n");
+
+	priv->fw_loaded = true;
+
+free:
+	iounmap(md32_en_cfg_base);
+free_pmb:
+	iounmap(pmb_addr);
+
+	return ret ? ret : 0;
+}
+
+static int mt798x_2p5ge_phy_config_init(struct phy_device *phydev)
+{
+	struct pinctrl *pinctrl;
+	int ret;
+
+	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");
+
+	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 */
+	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;
+
+	/* In fact, if we disable autoneg, we can't link up correctly:
+	 *  2.5G/1G: Need AN to exchange master/slave information.
+	 *  100M: Without AN, link starts at half duplex (According to
+	 *        IEEE 802.3-2018), which this phy doesn't support.
+	 *   10M: Deprecated in this ethernet phy.
+	 */
+	if (phydev->autoneg == AUTONEG_DISABLE)
+		return -EOPNOTSUPP;
+
+	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;
+		/* FIXME:
+		 * The current firmware always enables rate adaptation mode.
+		 */
+		phydev->rate_matching = RATE_MATCH_PAUSE;
+	}
+
+	return 0;
+}
+
+static int mt798x_2p5ge_phy_get_rate_matching(struct phy_device *phydev,
+					      phy_interface_t iface)
+{
+	if (iface == PHY_INTERFACE_MODE_XGMII ||
+	    iface == PHY_INTERFACE_MODE_INTERNAL)
+		return RATE_MATCH_PAUSE;
+	return RATE_MATCH_NONE;
+}
+
+static const unsigned long supported_triggers =
+	(BIT(TRIGGER_NETDEV_FULL_DUPLEX) |
+	 BIT(TRIGGER_NETDEV_LINK)        |
+	 BIT(TRIGGER_NETDEV_LINK_10)     |
+	 BIT(TRIGGER_NETDEV_LINK_100)    |
+	 BIT(TRIGGER_NETDEV_LINK_1000)   |
+	 BIT(TRIGGER_NETDEV_LINK_2500)   |
+	 BIT(TRIGGER_NETDEV_RX)          |
+	 BIT(TRIGGER_NETDEV_TX));
+
+static int mt798x_2p5ge_phy_led_blink_set(struct phy_device *phydev, u8 index,
+					  unsigned long *delay_on,
+					  unsigned long *delay_off)
+{
+	struct mtk_i2p5ge_phy_priv *priv = phydev->priv;
+	bool blinking = false;
+	int err = 0;
+
+	if (index > 1)
+		return -EINVAL;
+
+	if (delay_on && delay_off && (*delay_on > 0) && (*delay_off > 0)) {
+		blinking = true;
+		*delay_on = 50;
+		*delay_off = 50;
+	}
+
+	err = mtk_phy_hw_led_blink_set(phydev, index, &priv->led_state,
+				       blinking);
+	if (err)
+		return err;
+
+	return mtk_phy_hw_led_on_set(phydev, index, &priv->led_state,
+				     MTK_2P5GPHY_LED_ON_MASK, false);
+}
+
+static int mt798x_2p5ge_phy_led_brightness_set(struct phy_device *phydev,
+					       u8 index,
+					       enum led_brightness value)
+{
+	struct mtk_i2p5ge_phy_priv *priv = phydev->priv;
+	int err;
+
+	err = mtk_phy_hw_led_blink_set(phydev, index, &priv->led_state, false);
+	if (err)
+		return err;
+
+	return mtk_phy_hw_led_on_set(phydev, index, &priv->led_state,
+				     MTK_2P5GPHY_LED_ON_MASK,
+				     (value != LED_OFF));
+}
+
+static int mt798x_2p5ge_phy_led_hw_is_supported(struct phy_device *phydev,
+						u8 index, unsigned long rules)
+{
+	return mtk_phy_led_hw_is_supported(phydev, index, rules,
+					   supported_triggers);
+}
+
+static int mt798x_2p5ge_phy_led_hw_control_get(struct phy_device *phydev,
+					       u8 index, unsigned long *rules)
+{
+	struct mtk_i2p5ge_phy_priv *priv = phydev->priv;
+
+	return mtk_phy_led_hw_ctrl_get(phydev, index, rules, &priv->led_state,
+				       MTK_2P5GPHY_LED_ON_SET,
+				       MTK_2P5GPHY_LED_RX_BLINK_SET,
+				       MTK_2P5GPHY_LED_TX_BLINK_SET);
+};
+
+static int mt798x_2p5ge_phy_led_hw_control_set(struct phy_device *phydev,
+					       u8 index, unsigned long rules)
+{
+	struct mtk_i2p5ge_phy_priv *priv = phydev->priv;
+
+	return mtk_phy_led_hw_ctrl_set(phydev, index, rules, &priv->led_state,
+				       MTK_2P5GPHY_LED_ON_SET,
+				       MTK_2P5GPHY_LED_RX_BLINK_SET,
+				       MTK_2P5GPHY_LED_TX_BLINK_SET);
+};
+
+static int mt798x_2p5ge_phy_probe(struct phy_device *phydev)
+{
+	struct mtk_i2p5ge_phy_priv *priv;
+
+	priv = devm_kzalloc(&phydev->mdio.dev,
+			    sizeof(struct mtk_i2p5ge_phy_priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	switch (phydev->drv->phy_id) {
+	case MTK_2P5GPHY_ID_MT7988:
+		/* The original hardware only sets MDIO_DEVS_PMAPMD */
+		phydev->c45_ids.mmds_present |= MDIO_DEVS_PCS |
+						MDIO_DEVS_AN |
+						MDIO_DEVS_VEND1 |
+						MDIO_DEVS_VEND2;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	priv->fw_loaded = false;
+	phydev->priv = priv;
+
+	mtk_phy_leds_state_init(phydev);
+
+	return 0;
+}
+
+static struct phy_driver mtk_gephy_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,
+		.led_blink_set	= mt798x_2p5ge_phy_led_blink_set,
+		.led_brightness_set = mt798x_2p5ge_phy_led_brightness_set,
+		.led_hw_is_supported = mt798x_2p5ge_phy_led_hw_is_supported,
+		.led_hw_control_get = mt798x_2p5ge_phy_led_hw_control_get,
+		.led_hw_control_set = mt798x_2p5ge_phy_led_hw_control_set,
+	},
+};
+
+module_phy_driver(mtk_gephy_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 <SkyLake.Huang@xxxxxxxxxxxx>");
+MODULE_LICENSE("GPL");
+
+MODULE_DEVICE_TABLE(mdio, mtk_2p5ge_phy_tbl);
-- 
2.34.1