android_kernel_xiaomi_sm8350/drivers/net/gianfar_mii.c
Paul Gortmaker d031358754 [netdrvr] gianfar: Determine TBIPA value dynamically
TBIPA needs to be set to a value (on connected MDIO buses) that
doesn't conflict with PHYs on the bus.  By hardcoding it to 0x1f,
we were preventing boards with PHYs at 0x1f from working properly.
Instead, scan the bus when it comes up, and find an address that
doesn't have a PHY on it.  The TBI PHY configuration code then
trusts that the value in TBIPA is either safe, or doesn't matter
(ie - it's not an active bus with other PHYs).

Signed-off-by: Andy Fleming <afleming@freescale.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-04-29 01:57:57 -04:00

280 lines
7.0 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 <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;
}
static int gfar_mdio_probe(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
struct gianfar_mdio_data *pdata;
struct gfar_mii __iomem *regs;
struct gfar __iomem *enet_regs;
struct mii_bus *new_bus;
struct resource *r;
int i, err = 0;
if (NULL == dev)
return -EINVAL;
new_bus = kzalloc(sizeof(struct mii_bus), GFP_KERNEL);
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,
snprintf(new_bus->id, MII_BUS_ID_SIZE, "%x", pdev->id);
pdata = (struct gianfar_mdio_data *)pdev->dev.platform_data;
if (NULL == pdata) {
printk(KERN_ERR "gfar mdio %d: Missing platform data!\n", pdev->id);
return -ENODEV;
}
r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
/* Set the PHY base address */
regs = ioremap(r->start, sizeof (struct gfar_mii));
if (NULL == regs) {
err = -ENOMEM;
goto reg_map_fail;
}
new_bus->priv = (void __force *)regs;
new_bus->irq = pdata->irq;
new_bus->dev = dev;
dev_set_drvdata(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));
/* Scan the bus, looking for an empty spot for TBIPA */
gfar_write(&enet_regs->tbipa, 0);
for (i = PHY_MAX_ADDR; i > 0; i--) {
u32 phy_id;
int r;
r = get_phy_id(new_bus, i, &phy_id);
if (r)
return r;
if (phy_id == 0xffffffff)
break;
}
/* The bus is full. We don't support using 31 PHYs, sorry */
if (i == 0)
return -EBUSY;
gfar_write(&enet_regs->tbipa, i);
err = mdiobus_register(new_bus);
if (0 != err) {
printk (KERN_ERR "%s: Cannot register as MDIO bus\n",
new_bus->name);
goto bus_register_fail;
}
return 0;
bus_register_fail:
iounmap(regs);
reg_map_fail:
kfree(new_bus);
return err;
}
static int gfar_mdio_remove(struct device *dev)
{
struct mii_bus *bus = dev_get_drvdata(dev);
mdiobus_unregister(bus);
dev_set_drvdata(dev, NULL);
iounmap((void __iomem *)bus->priv);
bus->priv = NULL;
kfree(bus);
return 0;
}
static struct device_driver gianfar_mdio_driver = {
.name = "fsl-gianfar_mdio",
.bus = &platform_bus_type,
.probe = gfar_mdio_probe,
.remove = gfar_mdio_remove,
};
int __init gfar_mdio_init(void)
{
return driver_register(&gianfar_mdio_driver);
}
void gfar_mdio_exit(void)
{
driver_unregister(&gianfar_mdio_driver);
}