1 /* Copyright (c) 2013-2016, The Linux Foundation. All rights reserved.
3 * This program is free software; you can redistribute it and/or modify
4 * it under the terms of the GNU General Public License version 2 and
5 * only version 2 as published by the Free Software Foundation.
7 * This program is distributed in the hope that it will be useful,
8 * but WITHOUT ANY WARRANTY; without even the implied warranty of
9 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
10 * GNU General Public License for more details.
13 /* Qualcomm Technologies, Inc. EMAC PHY Controller driver.
16 #include <linux/module.h>
18 #include <linux/of_net.h>
19 #include <linux/of_mdio.h>
20 #include <linux/phy.h>
21 #include <linux/iopoll.h>
22 #include <linux/acpi.h>
26 #include "emac-sgmii.h"
28 /* EMAC base register offsets */
29 #define EMAC_MDIO_CTRL 0x001414
30 #define EMAC_PHY_STS 0x001418
31 #define EMAC_MDIO_EX_CTRL 0x001440
34 #define MDIO_MODE BIT(30)
35 #define MDIO_PR BIT(29)
36 #define MDIO_AP_EN BIT(28)
37 #define MDIO_BUSY BIT(27)
38 #define MDIO_CLK_SEL_BMSK 0x7000000
39 #define MDIO_CLK_SEL_SHFT 24
40 #define MDIO_START BIT(23)
41 #define SUP_PREAMBLE BIT(22)
42 #define MDIO_RD_NWR BIT(21)
43 #define MDIO_REG_ADDR_BMSK 0x1f0000
44 #define MDIO_REG_ADDR_SHFT 16
45 #define MDIO_DATA_BMSK 0xffff
46 #define MDIO_DATA_SHFT 0
49 #define PHY_ADDR_BMSK 0x1f0000
50 #define PHY_ADDR_SHFT 16
52 #define MDIO_CLK_25_4 0
53 #define MDIO_CLK_25_28 7
55 #define MDIO_WAIT_TIMES 1000
57 #define EMAC_LINK_SPEED_DEFAULT (\
58 EMAC_LINK_SPEED_10_HALF |\
59 EMAC_LINK_SPEED_10_FULL |\
60 EMAC_LINK_SPEED_100_HALF |\
61 EMAC_LINK_SPEED_100_FULL |\
62 EMAC_LINK_SPEED_1GB_FULL)
65 * emac_phy_mdio_autopoll_disable() - disable mdio autopoll
66 * @adpt: the emac adapter
68 * The autopoll feature takes over the MDIO bus. In order for
69 * the PHY driver to be able to talk to the PHY over the MDIO
70 * bus, we need to temporarily disable the autopoll feature.
72 static int emac_phy_mdio_autopoll_disable(struct emac_adapter *adpt)
76 /* disable autopoll */
77 emac_reg_update32(adpt->base + EMAC_MDIO_CTRL, MDIO_AP_EN, 0);
79 /* wait for any mdio polling to complete */
80 if (!readl_poll_timeout(adpt->base + EMAC_MDIO_CTRL, val,
81 !(val & MDIO_BUSY), 100, MDIO_WAIT_TIMES * 100))
84 /* failed to disable; ensure it is enabled before returning */
85 emac_reg_update32(adpt->base + EMAC_MDIO_CTRL, 0, MDIO_AP_EN);
91 * emac_phy_mdio_autopoll_disable() - disable mdio autopoll
92 * @adpt: the emac adapter
94 * The EMAC has the ability to poll the external PHY on the MDIO
95 * bus for link state changes. This eliminates the need for the
96 * driver to poll the phy. If if the link state does change,
97 * the EMAC issues an interrupt on behalf of the PHY.
99 static void emac_phy_mdio_autopoll_enable(struct emac_adapter *adpt)
101 emac_reg_update32(adpt->base + EMAC_MDIO_CTRL, 0, MDIO_AP_EN);
104 static int emac_mdio_read(struct mii_bus *bus, int addr, int regnum)
106 struct emac_adapter *adpt = bus->priv;
110 ret = emac_phy_mdio_autopoll_disable(adpt);
114 emac_reg_update32(adpt->base + EMAC_PHY_STS, PHY_ADDR_BMSK,
115 (addr << PHY_ADDR_SHFT));
118 ((MDIO_CLK_25_4 << MDIO_CLK_SEL_SHFT) & MDIO_CLK_SEL_BMSK) |
119 ((regnum << MDIO_REG_ADDR_SHFT) & MDIO_REG_ADDR_BMSK) |
120 MDIO_START | MDIO_RD_NWR;
122 writel(reg, adpt->base + EMAC_MDIO_CTRL);
124 if (readl_poll_timeout(adpt->base + EMAC_MDIO_CTRL, reg,
125 !(reg & (MDIO_START | MDIO_BUSY)),
126 100, MDIO_WAIT_TIMES * 100))
129 ret = (reg >> MDIO_DATA_SHFT) & MDIO_DATA_BMSK;
131 emac_phy_mdio_autopoll_enable(adpt);
136 static int emac_mdio_write(struct mii_bus *bus, int addr, int regnum, u16 val)
138 struct emac_adapter *adpt = bus->priv;
142 ret = emac_phy_mdio_autopoll_disable(adpt);
146 emac_reg_update32(adpt->base + EMAC_PHY_STS, PHY_ADDR_BMSK,
147 (addr << PHY_ADDR_SHFT));
150 ((MDIO_CLK_25_4 << MDIO_CLK_SEL_SHFT) & MDIO_CLK_SEL_BMSK) |
151 ((regnum << MDIO_REG_ADDR_SHFT) & MDIO_REG_ADDR_BMSK) |
152 ((val << MDIO_DATA_SHFT) & MDIO_DATA_BMSK) |
155 writel(reg, adpt->base + EMAC_MDIO_CTRL);
157 if (readl_poll_timeout(adpt->base + EMAC_MDIO_CTRL, reg,
158 !(reg & (MDIO_START | MDIO_BUSY)), 100,
159 MDIO_WAIT_TIMES * 100))
162 emac_phy_mdio_autopoll_enable(adpt);
167 /* Configure the MDIO bus and connect the external PHY */
168 int emac_phy_config(struct platform_device *pdev, struct emac_adapter *adpt)
170 struct device_node *np = pdev->dev.of_node;
171 struct mii_bus *mii_bus;
174 /* Create the mii_bus object for talking to the MDIO bus */
175 adpt->mii_bus = mii_bus = devm_mdiobus_alloc(&pdev->dev);
179 mii_bus->name = "emac-mdio";
180 snprintf(mii_bus->id, MII_BUS_ID_SIZE, "%s", pdev->name);
181 mii_bus->read = emac_mdio_read;
182 mii_bus->write = emac_mdio_write;
183 mii_bus->parent = &pdev->dev;
184 mii_bus->priv = adpt;
186 if (has_acpi_companion(&pdev->dev)) {
189 ret = mdiobus_register(mii_bus);
191 dev_err(&pdev->dev, "could not register mdio bus\n");
194 ret = device_property_read_u32(&pdev->dev, "phy-channel",
197 /* If we can't read a valid phy address, then assume
198 * that there is only one phy on this mdio bus.
200 adpt->phydev = phy_find_first(mii_bus);
202 adpt->phydev = mdiobus_get_phy(mii_bus, phy_addr);
205 struct device_node *phy_np;
207 ret = of_mdiobus_register(mii_bus, np);
209 dev_err(&pdev->dev, "could not register mdio bus\n");
213 phy_np = of_parse_phandle(np, "phy-handle", 0);
214 adpt->phydev = of_phy_find_device(phy_np);
219 dev_err(&pdev->dev, "could not find external phy\n");
220 mdiobus_unregister(mii_bus);
224 if (adpt->phydev->drv)
225 phy_attached_print(adpt->phydev, NULL);