linux/drivers/net/ethernet/freescale/xgmac_mdio.c

276 lines
6.4 KiB
C

/*
* QorIQ 10G MDIO Controller
*
* Copyright 2012 Freescale Semiconductor, Inc.
*
* Authors: Andy Fleming <afleming@freescale.com>
* Timur Tabi <timur@freescale.com>
*
* This file is licensed under the terms of the GNU General Public License
* version 2. This program is licensed "as is" without any warranty of any
* kind, whether express or implied.
*/
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/phy.h>
#include <linux/mdio.h>
#include <linux/of_address.h>
#include <linux/of_platform.h>
#include <linux/of_mdio.h>
/* Number of microseconds to wait for a register to respond */
#define TIMEOUT 1000
struct tgec_mdio_controller {
__be32 reserved[12];
__be32 mdio_stat; /* MDIO configuration and status */
__be32 mdio_ctl; /* MDIO control */
__be32 mdio_data; /* MDIO data */
__be32 mdio_addr; /* MDIO address */
} __packed;
#define MDIO_STAT_CLKDIV(x) (((x>>1) & 0xff) << 8)
#define MDIO_STAT_BSY (1 << 0)
#define MDIO_STAT_RD_ER (1 << 1)
#define MDIO_CTL_DEV_ADDR(x) (x & 0x1f)
#define MDIO_CTL_PORT_ADDR(x) ((x & 0x1f) << 5)
#define MDIO_CTL_PRE_DIS (1 << 10)
#define MDIO_CTL_SCAN_EN (1 << 11)
#define MDIO_CTL_POST_INC (1 << 14)
#define MDIO_CTL_READ (1 << 15)
#define MDIO_DATA(x) (x & 0xffff)
#define MDIO_DATA_BSY (1 << 31)
/*
* Wait untill the MDIO bus is free
*/
static int xgmac_wait_until_free(struct device *dev,
struct tgec_mdio_controller __iomem *regs)
{
uint32_t status;
/* Wait till the bus is free */
status = spin_event_timeout(
!((in_be32(&regs->mdio_stat)) & MDIO_STAT_BSY), TIMEOUT, 0);
if (!status) {
dev_err(dev, "timeout waiting for bus to be free\n");
return -ETIMEDOUT;
}
return 0;
}
/*
* Wait till the MDIO read or write operation is complete
*/
static int xgmac_wait_until_done(struct device *dev,
struct tgec_mdio_controller __iomem *regs)
{
uint32_t status;
/* Wait till the MDIO write is complete */
status = spin_event_timeout(
!((in_be32(&regs->mdio_data)) & MDIO_DATA_BSY), TIMEOUT, 0);
if (!status) {
dev_err(dev, "timeout waiting for operation to complete\n");
return -ETIMEDOUT;
}
return 0;
}
/*
* Write value to the PHY for this device to the register at regnum,waiting
* until the write is done before it returns. All PHY configuration has to be
* done through the TSEC1 MIIM regs.
*/
static int xgmac_mdio_write(struct mii_bus *bus, int phy_id, int regnum, u16 value)
{
struct tgec_mdio_controller __iomem *regs = bus->priv;
uint16_t dev_addr = regnum >> 16;
int ret;
/* Setup the MII Mgmt clock speed */
out_be32(&regs->mdio_stat, MDIO_STAT_CLKDIV(100));
ret = xgmac_wait_until_free(&bus->dev, regs);
if (ret)
return ret;
/* Set the port and dev addr */
out_be32(&regs->mdio_ctl,
MDIO_CTL_PORT_ADDR(phy_id) | MDIO_CTL_DEV_ADDR(dev_addr));
/* Set the register address */
out_be32(&regs->mdio_addr, regnum & 0xffff);
ret = xgmac_wait_until_free(&bus->dev, regs);
if (ret)
return ret;
/* Write the value to the register */
out_be32(&regs->mdio_data, MDIO_DATA(value));
ret = xgmac_wait_until_done(&bus->dev, regs);
if (ret)
return ret;
return 0;
}
/*
* Reads from register regnum in the PHY for device dev, returning the value.
* Clears miimcom first. All PHY configuration has to be done through the
* TSEC1 MIIM regs.
*/
static int xgmac_mdio_read(struct mii_bus *bus, int phy_id, int regnum)
{
struct tgec_mdio_controller __iomem *regs = bus->priv;
uint16_t dev_addr = regnum >> 16;
uint32_t mdio_ctl;
uint16_t value;
int ret;
/* Setup the MII Mgmt clock speed */
out_be32(&regs->mdio_stat, MDIO_STAT_CLKDIV(100));
ret = xgmac_wait_until_free(&bus->dev, regs);
if (ret)
return ret;
/* Set the Port and Device Addrs */
mdio_ctl = MDIO_CTL_PORT_ADDR(phy_id) | MDIO_CTL_DEV_ADDR(dev_addr);
out_be32(&regs->mdio_ctl, mdio_ctl);
/* Set the register address */
out_be32(&regs->mdio_addr, regnum & 0xffff);
ret = xgmac_wait_until_free(&bus->dev, regs);
if (ret)
return ret;
/* Initiate the read */
out_be32(&regs->mdio_ctl, mdio_ctl | MDIO_CTL_READ);
ret = xgmac_wait_until_done(&bus->dev, regs);
if (ret)
return ret;
/* Return all Fs if nothing was there */
if (in_be32(&regs->mdio_stat) & MDIO_STAT_RD_ER) {
dev_err(&bus->dev, "MDIO read error\n");
return 0xffff;
}
value = in_be32(&regs->mdio_data) & 0xffff;
dev_dbg(&bus->dev, "read %04x\n", value);
return value;
}
/* Reset the MIIM registers, and wait for the bus to free */
static int xgmac_mdio_reset(struct mii_bus *bus)
{
struct tgec_mdio_controller __iomem *regs = bus->priv;
int ret;
mutex_lock(&bus->mdio_lock);
/* Setup the MII Mgmt clock speed */
out_be32(&regs->mdio_stat, MDIO_STAT_CLKDIV(100));
ret = xgmac_wait_until_free(&bus->dev, regs);
mutex_unlock(&bus->mdio_lock);
return ret;
}
static int xgmac_mdio_probe(struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node;
struct mii_bus *bus;
struct resource res;
int ret;
ret = of_address_to_resource(np, 0, &res);
if (ret) {
dev_err(&pdev->dev, "could not obtain address\n");
return ret;
}
bus = mdiobus_alloc_size(PHY_MAX_ADDR * sizeof(int));
if (!bus)
return -ENOMEM;
bus->name = "Freescale XGMAC MDIO Bus";
bus->read = xgmac_mdio_read;
bus->write = xgmac_mdio_write;
bus->reset = xgmac_mdio_reset;
bus->irq = bus->priv;
bus->parent = &pdev->dev;
snprintf(bus->id, MII_BUS_ID_SIZE, "%llx", (unsigned long long)res.start);
/* Set the PHY base address */
bus->priv = of_iomap(np, 0);
if (!bus->priv) {
ret = -ENOMEM;
goto err_ioremap;
}
ret = of_mdiobus_register(bus, np);
if (ret) {
dev_err(&pdev->dev, "cannot register MDIO bus\n");
goto err_registration;
}
platform_set_drvdata(pdev, bus);
return 0;
err_registration:
iounmap(bus->priv);
err_ioremap:
mdiobus_free(bus);
return ret;
}
static int xgmac_mdio_remove(struct platform_device *pdev)
{
struct mii_bus *bus = platform_get_drvdata(pdev);
mdiobus_unregister(bus);
iounmap(bus->priv);
mdiobus_free(bus);
return 0;
}
static struct of_device_id xgmac_mdio_match[] = {
{
.compatible = "fsl,fman-xmdio",
},
{},
};
MODULE_DEVICE_TABLE(of, xgmac_mdio_match);
static struct platform_driver xgmac_mdio_driver = {
.driver = {
.name = "fsl-fman_xmdio",
.of_match_table = xgmac_mdio_match,
},
.probe = xgmac_mdio_probe,
.remove = xgmac_mdio_remove,
};
module_platform_driver(xgmac_mdio_driver);
MODULE_DESCRIPTION("Freescale QorIQ 10G MDIO Controller");
MODULE_LICENSE("GPL v2");