summaryrefslogtreecommitdiff
path: root/drivers/net/ethernet/qualcomm/emac/emac-phy.c
blob: 5c94af7bb6b65c47f8e34e425845c025c17b4f80 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
// SPDX-License-Identifier: GPL-2.0-only
/* Copyright (c) 2013-2016, The Linux Foundation. All rights reserved.
 */

/* Qualcomm Technologies, Inc. EMAC PHY Controller driver.
 */

#include <linux/of_mdio.h>
#include <linux/phy.h>
#include <linux/iopoll.h>
#include <linux/acpi.h>
#include "emac.h"

/* EMAC base register offsets */
#define EMAC_MDIO_CTRL                                        0x001414
#define EMAC_PHY_STS                                          0x001418
#define EMAC_MDIO_EX_CTRL                                     0x001440

/* EMAC_MDIO_CTRL */
#define MDIO_MODE                                              BIT(30)
#define MDIO_PR                                                BIT(29)
#define MDIO_AP_EN                                             BIT(28)
#define MDIO_BUSY                                              BIT(27)
#define MDIO_CLK_SEL_BMSK                                    0x7000000
#define MDIO_CLK_SEL_SHFT                                           24
#define MDIO_START                                             BIT(23)
#define SUP_PREAMBLE                                           BIT(22)
#define MDIO_RD_NWR                                            BIT(21)
#define MDIO_REG_ADDR_BMSK                                    0x1f0000
#define MDIO_REG_ADDR_SHFT                                          16
#define MDIO_DATA_BMSK                                          0xffff
#define MDIO_DATA_SHFT                                               0

/* EMAC_PHY_STS */
#define PHY_ADDR_BMSK                                         0x1f0000
#define PHY_ADDR_SHFT                                               16

#define MDIO_CLK_25_4                                                0
#define MDIO_CLK_25_28                                               7

#define MDIO_WAIT_TIMES                                           1000
#define MDIO_STATUS_DELAY_TIME                                       1

static int emac_mdio_read(struct mii_bus *bus, int addr, int regnum)
{
	struct emac_adapter *adpt = bus->priv;
	u32 reg;

	emac_reg_update32(adpt->base + EMAC_PHY_STS, PHY_ADDR_BMSK,
			  (addr << PHY_ADDR_SHFT));

	reg = SUP_PREAMBLE |
	      ((MDIO_CLK_25_4 << MDIO_CLK_SEL_SHFT) & MDIO_CLK_SEL_BMSK) |
	      ((regnum << MDIO_REG_ADDR_SHFT) & MDIO_REG_ADDR_BMSK) |
	      MDIO_START | MDIO_RD_NWR;

	writel(reg, adpt->base + EMAC_MDIO_CTRL);

	if (readl_poll_timeout(adpt->base + EMAC_MDIO_CTRL, reg,
			       !(reg & (MDIO_START | MDIO_BUSY)),
			       MDIO_STATUS_DELAY_TIME, MDIO_WAIT_TIMES * 100))
		return -EIO;

	return (reg >> MDIO_DATA_SHFT) & MDIO_DATA_BMSK;
}

static int emac_mdio_write(struct mii_bus *bus, int addr, int regnum, u16 val)
{
	struct emac_adapter *adpt = bus->priv;
	u32 reg;

	emac_reg_update32(adpt->base + EMAC_PHY_STS, PHY_ADDR_BMSK,
			  (addr << PHY_ADDR_SHFT));

	reg = SUP_PREAMBLE |
		((MDIO_CLK_25_4 << MDIO_CLK_SEL_SHFT) & MDIO_CLK_SEL_BMSK) |
		((regnum << MDIO_REG_ADDR_SHFT) & MDIO_REG_ADDR_BMSK) |
		((val << MDIO_DATA_SHFT) & MDIO_DATA_BMSK) |
		MDIO_START;

	writel(reg, adpt->base + EMAC_MDIO_CTRL);

	if (readl_poll_timeout(adpt->base + EMAC_MDIO_CTRL, reg,
			       !(reg & (MDIO_START | MDIO_BUSY)),
			       MDIO_STATUS_DELAY_TIME, MDIO_WAIT_TIMES * 100))
		return -EIO;

	return 0;
}

/* Configure the MDIO bus and connect the external PHY */
int emac_phy_config(struct platform_device *pdev, struct emac_adapter *adpt)
{
	struct device_node *np = pdev->dev.of_node;
	struct mii_bus *mii_bus;
	int ret;

	/* Create the mii_bus object for talking to the MDIO bus */
	adpt->mii_bus = mii_bus = devm_mdiobus_alloc(&pdev->dev);
	if (!mii_bus)
		return -ENOMEM;

	mii_bus->name = "emac-mdio";
	snprintf(mii_bus->id, MII_BUS_ID_SIZE, "%s", pdev->name);
	mii_bus->read = emac_mdio_read;
	mii_bus->write = emac_mdio_write;
	mii_bus->parent = &pdev->dev;
	mii_bus->priv = adpt;

	if (has_acpi_companion(&pdev->dev)) {
		u32 phy_addr;

		ret = mdiobus_register(mii_bus);
		if (ret) {
			dev_err(&pdev->dev, "could not register mdio bus\n");
			return ret;
		}
		ret = device_property_read_u32(&pdev->dev, "phy-channel",
					       &phy_addr);
		if (ret)
			/* If we can't read a valid phy address, then assume
			 * that there is only one phy on this mdio bus.
			 */
			adpt->phydev = phy_find_first(mii_bus);
		else
			adpt->phydev = mdiobus_get_phy(mii_bus, phy_addr);

		/* of_phy_find_device() claims a reference to the phydev,
		 * so we do that here manually as well. When the driver
		 * later unloads, it can unilaterally drop the reference
		 * without worrying about ACPI vs DT.
		 */
		if (adpt->phydev)
			get_device(&adpt->phydev->mdio.dev);
	} else {
		struct device_node *phy_np;

		ret = of_mdiobus_register(mii_bus, np);
		if (ret) {
			dev_err(&pdev->dev, "could not register mdio bus\n");
			return ret;
		}

		phy_np = of_parse_phandle(np, "phy-handle", 0);
		adpt->phydev = of_phy_find_device(phy_np);
		of_node_put(phy_np);
	}

	if (!adpt->phydev) {
		dev_err(&pdev->dev, "could not find external phy\n");
		mdiobus_unregister(mii_bus);
		return -ENODEV;
	}

	return 0;
}