linux/drivers/net/gianfar_mii.c

378 lines
8.8 KiB
C

/*
* drivers/net/gianfar_mii.c
*
* Gianfar Ethernet Driver -- MIIM bus implementation
* Provides Bus interface for MIIM regs
*
* Author: Andy Fleming
* Maintainer: Kumar Gala
*
* Copyright (c) 2002-2004 Freescale Semiconductor, Inc.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*
*/
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/unistd.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/skbuff.h>
#include <linux/spinlock.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/crc32.h>
#include <linux/mii.h>
#include <linux/phy.h>
#include <linux/of.h>
#include <linux/of_platform.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/uaccess.h>
#include "gianfar.h"
#include "gianfar_mii.h"
/*
* Write value to the PHY at mii_id at register regnum,
* on the bus attached to the local interface, which may be different from the
* generic mdio bus (tied to a single interface), waiting until the write is
* done before returning. This is helpful in programming interfaces like
* the TBI which control interfaces like onchip SERDES and are always tied to
* the local mdio pins, which may not be the same as system mdio bus, used for
* controlling the external PHYs, for example.
*/
int gfar_local_mdio_write(struct gfar_mii __iomem *regs, int mii_id,
int regnum, u16 value)
{
/* Set the PHY address and the register address we want to write */
gfar_write(&regs->miimadd, (mii_id << 8) | regnum);
/* Write out the value we want */
gfar_write(&regs->miimcon, value);
/* Wait for the transaction to finish */
while (gfar_read(&regs->miimind) & MIIMIND_BUSY)
cpu_relax();
return 0;
}
/*
* Read the bus for PHY at addr mii_id, register regnum, and
* return the value. Clears miimcom first. All PHY operation
* done on the bus attached to the local interface,
* which may be different from the generic mdio bus
* This is helpful in programming interfaces like
* the TBI which, inturn, control interfaces like onchip SERDES
* and are always tied to the local mdio pins, which may not be the
* same as system mdio bus, used for controlling the external PHYs, for eg.
*/
int gfar_local_mdio_read(struct gfar_mii __iomem *regs, int mii_id, int regnum)
{
u16 value;
/* Set the PHY address and the register address we want to read */
gfar_write(&regs->miimadd, (mii_id << 8) | regnum);
/* Clear miimcom, and then initiate a read */
gfar_write(&regs->miimcom, 0);
gfar_write(&regs->miimcom, MII_READ_COMMAND);
/* Wait for the transaction to finish */
while (gfar_read(&regs->miimind) & (MIIMIND_NOTVALID | MIIMIND_BUSY))
cpu_relax();
/* Grab the value of the register from miimstat */
value = gfar_read(&regs->miimstat);
return value;
}
/* Write value to the PHY at mii_id at register regnum,
* on the bus, waiting until the write is done before returning.
* All PHY configuration is done through the TSEC1 MIIM regs */
int gfar_mdio_write(struct mii_bus *bus, int mii_id, int regnum, u16 value)
{
struct gfar_mii __iomem *regs = (void __iomem *)bus->priv;
/* Write to the local MII regs */
return(gfar_local_mdio_write(regs, mii_id, regnum, value));
}
/* Read the bus for PHY at addr mii_id, register regnum, and
* return the value. Clears miimcom first. All PHY
* configuration has to be done through the TSEC1 MIIM regs */
int gfar_mdio_read(struct mii_bus *bus, int mii_id, int regnum)
{
struct gfar_mii __iomem *regs = (void __iomem *)bus->priv;
/* Read the local MII regs */
return(gfar_local_mdio_read(regs, mii_id, regnum));
}
/* Reset the MIIM registers, and wait for the bus to free */
static int gfar_mdio_reset(struct mii_bus *bus)
{
struct gfar_mii __iomem *regs = (void __iomem *)bus->priv;
unsigned int timeout = PHY_INIT_TIMEOUT;
mutex_lock(&bus->mdio_lock);
/* Reset the management interface */
gfar_write(&regs->miimcfg, MIIMCFG_RESET);
/* Setup the MII Mgmt clock speed */
gfar_write(&regs->miimcfg, MIIMCFG_INIT_VALUE);
/* Wait until the bus is free */
while ((gfar_read(&regs->miimind) & MIIMIND_BUSY) &&
--timeout)
cpu_relax();
mutex_unlock(&bus->mdio_lock);
if(timeout == 0) {
printk(KERN_ERR "%s: The MII Bus is stuck!\n",
bus->name);
return -EBUSY;
}
return 0;
}
/* Allocate an array which provides irq #s for each PHY on the given bus */
static int *create_irq_map(struct device_node *np)
{
int *irqs;
int i;
struct device_node *child = NULL;
irqs = kcalloc(PHY_MAX_ADDR, sizeof(int), GFP_KERNEL);
if (!irqs)
return NULL;
for (i = 0; i < PHY_MAX_ADDR; i++)
irqs[i] = PHY_POLL;
while ((child = of_get_next_child(np, child)) != NULL) {
int irq = irq_of_parse_and_map(child, 0);
const u32 *id;
if (irq == NO_IRQ)
continue;
id = of_get_property(child, "reg", NULL);
if (!id)
continue;
if (*id < PHY_MAX_ADDR && *id >= 0)
irqs[*id] = irq;
else
printk(KERN_WARNING "%s: "
"%d is not a valid PHY address\n",
np->full_name, *id);
}
return irqs;
}
void gfar_mdio_bus_name(char *name, struct device_node *np)
{
const u32 *reg;
reg = of_get_property(np, "reg", NULL);
snprintf(name, MII_BUS_ID_SIZE, "%s@%x", np->name, reg ? *reg : 0);
}
/* Scan the bus in reverse, looking for an empty spot */
static int gfar_mdio_find_free(struct mii_bus *new_bus)
{
int i;
for (i = PHY_MAX_ADDR; i > 0; i--) {
u32 phy_id;
if (get_phy_id(new_bus, i, &phy_id))
return -1;
if (phy_id == 0xffffffff)
break;
}
return i;
}
static int gfar_mdio_probe(struct of_device *ofdev,
const struct of_device_id *match)
{
struct gfar_mii __iomem *regs;
struct gfar __iomem *enet_regs;
struct mii_bus *new_bus;
int err = 0;
u64 addr, size;
struct device_node *np = ofdev->node;
struct device_node *tbi;
int tbiaddr = -1;
new_bus = mdiobus_alloc();
if (NULL == new_bus)
return -ENOMEM;
new_bus->name = "Gianfar MII Bus",
new_bus->read = &gfar_mdio_read,
new_bus->write = &gfar_mdio_write,
new_bus->reset = &gfar_mdio_reset,
gfar_mdio_bus_name(new_bus->id, np);
/* Set the PHY base address */
addr = of_translate_address(np, of_get_address(np, 0, &size, NULL));
regs = ioremap(addr, size);
if (NULL == regs) {
err = -ENOMEM;
goto err_free_bus;
}
new_bus->priv = (void __force *)regs;
new_bus->irq = create_irq_map(np);
if (new_bus->irq == NULL) {
err = -ENOMEM;
goto err_unmap_regs;
}
new_bus->parent = &ofdev->dev;
dev_set_drvdata(&ofdev->dev, new_bus);
/*
* This is mildly evil, but so is our hardware for doing this.
* Also, we have to cast back to struct gfar_mii because of
* definition weirdness done in gianfar.h.
*/
enet_regs = (struct gfar __iomem *)
((char *)regs - offsetof(struct gfar, gfar_mii_regs));
for_each_child_of_node(np, tbi) {
if (!strncmp(tbi->type, "tbi-phy", 8))
break;
}
if (tbi) {
const u32 *prop = of_get_property(tbi, "reg", NULL);
if (prop)
tbiaddr = *prop;
}
if (tbiaddr == -1) {
gfar_write(&enet_regs->tbipa, 0);
tbiaddr = gfar_mdio_find_free(new_bus);
}
/*
* We define TBIPA at 0 to be illegal, opting to fail for boards that
* have PHYs at 1-31, rather than change tbipa and rescan.
*/
if (tbiaddr == 0) {
err = -EBUSY;
goto err_free_irqs;
}
gfar_write(&enet_regs->tbipa, tbiaddr);
/*
* The TBIPHY-only buses will find PHYs at every address,
* so we mask them all but the TBI
*/
if (!of_device_is_compatible(np, "fsl,gianfar-mdio"))
new_bus->phy_mask = ~(1 << tbiaddr);
err = mdiobus_register(new_bus);
if (err != 0) {
printk (KERN_ERR "%s: Cannot register as MDIO bus\n",
new_bus->name);
goto err_free_irqs;
}
return 0;
err_free_irqs:
kfree(new_bus->irq);
err_unmap_regs:
iounmap(regs);
err_free_bus:
mdiobus_free(new_bus);
return err;
}
static int gfar_mdio_remove(struct of_device *ofdev)
{
struct mii_bus *bus = dev_get_drvdata(&ofdev->dev);
mdiobus_unregister(bus);
dev_set_drvdata(&ofdev->dev, NULL);
iounmap((void __iomem *)bus->priv);
bus->priv = NULL;
kfree(bus->irq);
mdiobus_free(bus);
return 0;
}
static struct of_device_id gfar_mdio_match[] =
{
{
.compatible = "fsl,gianfar-mdio",
},
{
.compatible = "fsl,gianfar-tbi",
},
{
.type = "mdio",
.compatible = "gianfar",
},
{},
};
static struct of_platform_driver gianfar_mdio_driver = {
.name = "fsl-gianfar_mdio",
.match_table = gfar_mdio_match,
.probe = gfar_mdio_probe,
.remove = gfar_mdio_remove,
};
int __init gfar_mdio_init(void)
{
return of_register_platform_driver(&gianfar_mdio_driver);
}
void gfar_mdio_exit(void)
{
of_unregister_platform_driver(&gianfar_mdio_driver);
}