1/* 10G controller driver for Samsung SoCs
2 *
3 * Copyright (C) 2013 Samsung Electronics Co., Ltd.
4 *		http://www.samsung.com
5 *
6 * Author: Siva Reddy Kallam <siva.kallam@samsung.com>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 */
12
13#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
14
15#include <linux/io.h>
16#include <linux/mii.h>
17#include <linux/netdevice.h>
18#include <linux/platform_device.h>
19#include <linux/phy.h>
20#include <linux/slab.h>
21#include <linux/sxgbe_platform.h>
22
23#include "sxgbe_common.h"
24#include "sxgbe_reg.h"
25
26#define SXGBE_SMA_WRITE_CMD	0x01 /* write command */
27#define SXGBE_SMA_PREAD_CMD	0x02 /* post read  increament address */
28#define SXGBE_SMA_READ_CMD	0x03 /* read command */
29#define SXGBE_SMA_SKIP_ADDRFRM	0x00040000 /* skip the address frame */
30#define SXGBE_MII_BUSY		0x00400000 /* mii busy */
31
32static int sxgbe_mdio_busy_wait(void __iomem *ioaddr, unsigned int mii_data)
33{
34	unsigned long fin_time = jiffies + 3 * HZ; /* 3 seconds */
35
36	while (!time_after(jiffies, fin_time)) {
37		if (!(readl(ioaddr + mii_data) & SXGBE_MII_BUSY))
38			return 0;
39		cpu_relax();
40	}
41
42	return -EBUSY;
43}
44
45static void sxgbe_mdio_ctrl_data(struct sxgbe_priv_data *sp, u32 cmd,
46				 u16 phydata)
47{
48	u32 reg = phydata;
49
50	reg |= (cmd << 16) | SXGBE_SMA_SKIP_ADDRFRM |
51	       ((sp->clk_csr & 0x7) << 19) | SXGBE_MII_BUSY;
52	writel(reg, sp->ioaddr + sp->hw->mii.data);
53}
54
55static void sxgbe_mdio_c45(struct sxgbe_priv_data *sp, u32 cmd, int phyaddr,
56			   int phyreg, u16 phydata)
57{
58	u32 reg;
59
60	/* set mdio address register */
61	reg = ((phyreg >> 16) & 0x1f) << 21;
62	reg |= (phyaddr << 16) | (phyreg & 0xffff);
63	writel(reg, sp->ioaddr + sp->hw->mii.addr);
64
65	sxgbe_mdio_ctrl_data(sp, cmd, phydata);
66}
67
68static void sxgbe_mdio_c22(struct sxgbe_priv_data *sp, u32 cmd, int phyaddr,
69			   int phyreg, u16 phydata)
70{
71	u32 reg;
72
73	writel(1 << phyaddr, sp->ioaddr + SXGBE_MDIO_CLAUSE22_PORT_REG);
74
75	/* set mdio address register */
76	reg = (phyaddr << 16) | (phyreg & 0x1f);
77	writel(reg, sp->ioaddr + sp->hw->mii.addr);
78
79	sxgbe_mdio_ctrl_data(sp, cmd, phydata);
80}
81
82static int sxgbe_mdio_access(struct sxgbe_priv_data *sp, u32 cmd, int phyaddr,
83			     int phyreg, u16 phydata)
84{
85	const struct mii_regs *mii = &sp->hw->mii;
86	int rc;
87
88	rc = sxgbe_mdio_busy_wait(sp->ioaddr, mii->data);
89	if (rc < 0)
90		return rc;
91
92	if (phyreg & MII_ADDR_C45) {
93		sxgbe_mdio_c45(sp, cmd, phyaddr, phyreg, phydata);
94	} else {
95		 /* Ports 0-3 only support C22. */
96		if (phyaddr >= 4)
97			return -ENODEV;
98
99		sxgbe_mdio_c22(sp, cmd, phyaddr, phyreg, phydata);
100	}
101
102	return sxgbe_mdio_busy_wait(sp->ioaddr, mii->data);
103}
104
105/**
106 * sxgbe_mdio_read
107 * @bus: points to the mii_bus structure
108 * @phyaddr: address of phy port
109 * @phyreg: address of register with in phy register
110 * Description: this function used for C45 and C22 MDIO Read
111 */
112static int sxgbe_mdio_read(struct mii_bus *bus, int phyaddr, int phyreg)
113{
114	struct net_device *ndev = bus->priv;
115	struct sxgbe_priv_data *priv = netdev_priv(ndev);
116	int rc;
117
118	rc = sxgbe_mdio_access(priv, SXGBE_SMA_READ_CMD, phyaddr, phyreg, 0);
119	if (rc < 0)
120		return rc;
121
122	return readl(priv->ioaddr + priv->hw->mii.data) & 0xffff;
123}
124
125/**
126 * sxgbe_mdio_write
127 * @bus: points to the mii_bus structure
128 * @phyaddr: address of phy port
129 * @phyreg: address of phy registers
130 * @phydata: data to be written into phy register
131 * Description: this function is used for C45 and C22 MDIO write
132 */
133static int sxgbe_mdio_write(struct mii_bus *bus, int phyaddr, int phyreg,
134			     u16 phydata)
135{
136	struct net_device *ndev = bus->priv;
137	struct sxgbe_priv_data *priv = netdev_priv(ndev);
138
139	return sxgbe_mdio_access(priv, SXGBE_SMA_WRITE_CMD, phyaddr, phyreg,
140				 phydata);
141}
142
143int sxgbe_mdio_register(struct net_device *ndev)
144{
145	struct mii_bus *mdio_bus;
146	struct sxgbe_priv_data *priv = netdev_priv(ndev);
147	struct sxgbe_mdio_bus_data *mdio_data = priv->plat->mdio_bus_data;
148	int err, phy_addr;
149	int *irqlist;
150	bool phy_found = false;
151	bool act;
152
153	/* allocate the new mdio bus */
154	mdio_bus = mdiobus_alloc();
155	if (!mdio_bus) {
156		netdev_err(ndev, "%s: mii bus allocation failed\n", __func__);
157		return -ENOMEM;
158	}
159
160	if (mdio_data->irqs)
161		irqlist = mdio_data->irqs;
162	else
163		irqlist = priv->mii_irq;
164
165	/* assign mii bus fields */
166	mdio_bus->name = "sxgbe";
167	mdio_bus->read = &sxgbe_mdio_read;
168	mdio_bus->write = &sxgbe_mdio_write;
169	snprintf(mdio_bus->id, MII_BUS_ID_SIZE, "%s-%x",
170		 mdio_bus->name, priv->plat->bus_id);
171	mdio_bus->priv = ndev;
172	mdio_bus->phy_mask = mdio_data->phy_mask;
173	mdio_bus->parent = priv->device;
174
175	/* register with kernel subsystem */
176	err = mdiobus_register(mdio_bus);
177	if (err != 0) {
178		netdev_err(ndev, "mdiobus register failed\n");
179		goto mdiobus_err;
180	}
181
182	for (phy_addr = 0; phy_addr < PHY_MAX_ADDR; phy_addr++) {
183		struct phy_device *phy = mdio_bus->phy_map[phy_addr];
184
185		if (phy) {
186			char irq_num[4];
187			char *irq_str;
188			/* If an IRQ was provided to be assigned after
189			 * the bus probe, do it here.
190			 */
191			if ((mdio_data->irqs == NULL) &&
192			    (mdio_data->probed_phy_irq > 0)) {
193				irqlist[phy_addr] = mdio_data->probed_phy_irq;
194				phy->irq = mdio_data->probed_phy_irq;
195			}
196
197			/* If we're  going to bind the MAC to this PHY bus,
198			 * and no PHY number was provided to the MAC,
199			 * use the one probed here.
200			 */
201			if (priv->plat->phy_addr == -1)
202				priv->plat->phy_addr = phy_addr;
203
204			act = (priv->plat->phy_addr == phy_addr);
205			switch (phy->irq) {
206			case PHY_POLL:
207				irq_str = "POLL";
208				break;
209			case PHY_IGNORE_INTERRUPT:
210				irq_str = "IGNORE";
211				break;
212			default:
213				sprintf(irq_num, "%d", phy->irq);
214				irq_str = irq_num;
215				break;
216			}
217			netdev_info(ndev, "PHY ID %08x at %d IRQ %s (%s)%s\n",
218				    phy->phy_id, phy_addr, irq_str,
219				    dev_name(&phy->dev), act ? " active" : "");
220			phy_found = true;
221		}
222	}
223
224	if (!phy_found) {
225		netdev_err(ndev, "PHY not found\n");
226		goto phyfound_err;
227	}
228
229	priv->mii = mdio_bus;
230
231	return 0;
232
233phyfound_err:
234	err = -ENODEV;
235	mdiobus_unregister(mdio_bus);
236mdiobus_err:
237	mdiobus_free(mdio_bus);
238	return err;
239}
240
241int sxgbe_mdio_unregister(struct net_device *ndev)
242{
243	struct sxgbe_priv_data *priv = netdev_priv(ndev);
244
245	if (!priv->mii)
246		return 0;
247
248	mdiobus_unregister(priv->mii);
249	priv->mii->priv = NULL;
250	mdiobus_free(priv->mii);
251	priv->mii = NULL;
252
253	return 0;
254}
255