1/*
  2 * This file is subject to the terms and conditions of the GNU General Public
  3 * License.  See the file "COPYING" in the main directory of this archive
  4 * for more details.
  5 *
  6 * Copyright (C) 2009 Cavium Networks
  7 */
  8
  9#include <linux/gfp.h>
 10#include <linux/init.h>
 11#include <linux/module.h>
 12#include <linux/platform_device.h>
 13#include <linux/phy.h>
 14
 15#include <asm/octeon/octeon.h>
 16#include <asm/octeon/cvmx-smix-defs.h>
 17
 18#define DRV_VERSION "1.0"
 19#define DRV_DESCRIPTION "Cavium Networks Octeon SMI/MDIO driver"
 20
 21struct octeon_mdiobus {
 22	struct mii_bus *mii_bus;
 23	int unit;
 24	int phy_irq[PHY_MAX_ADDR];
 25};
 26
 27static int octeon_mdiobus_read(struct mii_bus *bus, int phy_id, int regnum)
 28{
 29	struct octeon_mdiobus *p = bus->priv;
 30	union cvmx_smix_cmd smi_cmd;
 31	union cvmx_smix_rd_dat smi_rd;
 32	int timeout = 1000;
 33
 34	smi_cmd.u64 = 0;
 35	smi_cmd.s.phy_op = 1; /* MDIO_CLAUSE_22_READ */
 36	smi_cmd.s.phy_adr = phy_id;
 37	smi_cmd.s.reg_adr = regnum;
 38	cvmx_write_csr(CVMX_SMIX_CMD(p->unit), smi_cmd.u64);
 39
 40	do {
 41		/*
 42		 * Wait 1000 clocks so we don't saturate the RSL bus
 43		 * doing reads.
 44		 */
 45		cvmx_wait(1000);
 46		smi_rd.u64 = cvmx_read_csr(CVMX_SMIX_RD_DAT(p->unit));
 47	} while (smi_rd.s.pending && --timeout);
 48
 49	if (smi_rd.s.val)
 50		return smi_rd.s.dat;
 51	else
 52		return -EIO;
 53}
 54
 55static int octeon_mdiobus_write(struct mii_bus *bus, int phy_id,
 56				int regnum, u16 val)
 57{
 58	struct octeon_mdiobus *p = bus->priv;
 59	union cvmx_smix_cmd smi_cmd;
 60	union cvmx_smix_wr_dat smi_wr;
 61	int timeout = 1000;
 62
 63	smi_wr.u64 = 0;
 64	smi_wr.s.dat = val;
 65	cvmx_write_csr(CVMX_SMIX_WR_DAT(p->unit), smi_wr.u64);
 66
 67	smi_cmd.u64 = 0;
 68	smi_cmd.s.phy_op = 0; /* MDIO_CLAUSE_22_WRITE */
 69	smi_cmd.s.phy_adr = phy_id;
 70	smi_cmd.s.reg_adr = regnum;
 71	cvmx_write_csr(CVMX_SMIX_CMD(p->unit), smi_cmd.u64);
 72
 73	do {
 74		/*
 75		 * Wait 1000 clocks so we don't saturate the RSL bus
 76		 * doing reads.
 77		 */
 78		cvmx_wait(1000);
 79		smi_wr.u64 = cvmx_read_csr(CVMX_SMIX_WR_DAT(p->unit));
 80	} while (smi_wr.s.pending && --timeout);
 81
 82	if (timeout <= 0)
 83		return -EIO;
 84
 85	return 0;
 86}
 87
 88static int __devinit octeon_mdiobus_probe(struct platform_device *pdev)
 89{
 90	struct octeon_mdiobus *bus;
 91	union cvmx_smix_en smi_en;
 92	int i;
 93	int err = -ENOENT;
 94
 95	bus = devm_kzalloc(&pdev->dev, sizeof(*bus), GFP_KERNEL);
 96	if (!bus)
 97		return -ENOMEM;
 98
 99	/* The platform_device id is our unit number.  */
100	bus->unit = pdev->id;
101
102	bus->mii_bus = mdiobus_alloc();
103
104	if (!bus->mii_bus)
105		goto err;
106
107	smi_en.u64 = 0;
108	smi_en.s.en = 1;
109	cvmx_write_csr(CVMX_SMIX_EN(bus->unit), smi_en.u64);
110
111	/*
112	 * Standard Octeon evaluation boards don't support phy
113	 * interrupts, we need to poll.
114	 */
115	for (i = 0; i < PHY_MAX_ADDR; i++)
116		bus->phy_irq[i] = PHY_POLL;
117
118	bus->mii_bus->priv = bus;
119	bus->mii_bus->irq = bus->phy_irq;
120	bus->mii_bus->name = "mdio-octeon";
121	snprintf(bus->mii_bus->id, MII_BUS_ID_SIZE, "%x", bus->unit);
122	bus->mii_bus->parent = &pdev->dev;
123
124	bus->mii_bus->read = octeon_mdiobus_read;
125	bus->mii_bus->write = octeon_mdiobus_write;
126
127	dev_set_drvdata(&pdev->dev, bus);
128
129	err = mdiobus_register(bus->mii_bus);
130	if (err)
131		goto err_register;
132
133	dev_info(&pdev->dev, "Version " DRV_VERSION "\n");
134
135	return 0;
136err_register:
137	mdiobus_free(bus->mii_bus);
138
139err:
140	devm_kfree(&pdev->dev, bus);
141	smi_en.u64 = 0;
142	cvmx_write_csr(CVMX_SMIX_EN(bus->unit), smi_en.u64);
143	return err;
144}
145
146static int __devexit octeon_mdiobus_remove(struct platform_device *pdev)
147{
148	struct octeon_mdiobus *bus;
149	union cvmx_smix_en smi_en;
150
151	bus = dev_get_drvdata(&pdev->dev);
152
153	mdiobus_unregister(bus->mii_bus);
154	mdiobus_free(bus->mii_bus);
155	smi_en.u64 = 0;
156	cvmx_write_csr(CVMX_SMIX_EN(bus->unit), smi_en.u64);
157	return 0;
158}
159
160static struct platform_driver octeon_mdiobus_driver = {
161	.driver = {
162		.name		= "mdio-octeon",
163		.owner		= THIS_MODULE,
164	},
165	.probe		= octeon_mdiobus_probe,
166	.remove		= __devexit_p(octeon_mdiobus_remove),
167};
168
169void octeon_mdiobus_force_mod_depencency(void)
170{
171	/* Let ethernet drivers force us to be loaded.  */
172}
173EXPORT_SYMBOL(octeon_mdiobus_force_mod_depencency);
174
175static int __init octeon_mdiobus_mod_init(void)
176{
177	return platform_driver_register(&octeon_mdiobus_driver);
178}
179
180static void __exit octeon_mdiobus_mod_exit(void)
181{
182	platform_driver_unregister(&octeon_mdiobus_driver);
183}
184
185module_init(octeon_mdiobus_mod_init);
186module_exit(octeon_mdiobus_mod_exit);
187
188MODULE_DESCRIPTION(DRV_DESCRIPTION);
189MODULE_VERSION(DRV_VERSION);
190MODULE_AUTHOR("David Daney");
191MODULE_LICENSE("GPL");