linux-sg2042/drivers/net/fs_enet/mii-bitbang.c

409 lines
8.1 KiB
C

/*
* Combined Ethernet driver for Motorola MPC8xx and MPC82xx.
*
* Copyright (c) 2003 Intracom S.A.
* by Pantelis Antoniou <panto@intracom.gr>
*
* 2005 (c) MontaVista Software, Inc.
* Vitaly Bordug <vbordug@ru.mvista.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/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/string.h>
#include <linux/ptrace.h>
#include <linux/errno.h>
#include <linux/ioport.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/pci.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/mii.h>
#include <linux/ethtool.h>
#include <linux/bitops.h>
#include <linux/platform_device.h>
#include <asm/pgtable.h>
#include <asm/irq.h>
#include <asm/uaccess.h>
#include "fs_enet.h"
static int bitbang_prep_bit(u8 **datp, u8 *mskp,
struct fs_mii_bit *mii_bit)
{
void *dat;
int adv;
u8 msk;
dat = (void*) mii_bit->offset;
adv = mii_bit->bit >> 3;
dat = (char *)dat + adv;
msk = 1 << (7 - (mii_bit->bit & 7));
*datp = dat;
*mskp = msk;
return 0;
}
static inline void bb_set(u8 *p, u8 m)
{
out_8(p, in_8(p) | m);
}
static inline void bb_clr(u8 *p, u8 m)
{
out_8(p, in_8(p) & ~m);
}
static inline int bb_read(u8 *p, u8 m)
{
return (in_8(p) & m) != 0;
}
static inline void mdio_active(struct bb_info *bitbang)
{
bb_set(bitbang->mdio_dir, bitbang->mdio_dir_msk);
}
static inline void mdio_tristate(struct bb_info *bitbang )
{
bb_clr(bitbang->mdio_dir, bitbang->mdio_dir_msk);
}
static inline int mdio_read(struct bb_info *bitbang )
{
return bb_read(bitbang->mdio_dat, bitbang->mdio_dat_msk);
}
static inline void mdio(struct bb_info *bitbang , int what)
{
if (what)
bb_set(bitbang->mdio_dat, bitbang->mdio_dat_msk);
else
bb_clr(bitbang->mdio_dat, bitbang->mdio_dat_msk);
}
static inline void mdc(struct bb_info *bitbang , int what)
{
if (what)
bb_set(bitbang->mdc_dat, bitbang->mdc_msk);
else
bb_clr(bitbang->mdc_dat, bitbang->mdc_msk);
}
static inline void mii_delay(struct bb_info *bitbang )
{
udelay(bitbang->delay);
}
/* Utility to send the preamble, address, and register (common to read and write). */
static void bitbang_pre(struct bb_info *bitbang , int read, u8 addr, u8 reg)
{
int j;
/*
* Send a 32 bit preamble ('1's) with an extra '1' bit for good measure.
* The IEEE spec says this is a PHY optional requirement. The AMD
* 79C874 requires one after power up and one after a MII communications
* error. This means that we are doing more preambles than we need,
* but it is safer and will be much more robust.
*/
mdio_active(bitbang);
mdio(bitbang, 1);
for (j = 0; j < 32; j++) {
mdc(bitbang, 0);
mii_delay(bitbang);
mdc(bitbang, 1);
mii_delay(bitbang);
}
/* send the start bit (01) and the read opcode (10) or write (10) */
mdc(bitbang, 0);
mdio(bitbang, 0);
mii_delay(bitbang);
mdc(bitbang, 1);
mii_delay(bitbang);
mdc(bitbang, 0);
mdio(bitbang, 1);
mii_delay(bitbang);
mdc(bitbang, 1);
mii_delay(bitbang);
mdc(bitbang, 0);
mdio(bitbang, read);
mii_delay(bitbang);
mdc(bitbang, 1);
mii_delay(bitbang);
mdc(bitbang, 0);
mdio(bitbang, !read);
mii_delay(bitbang);
mdc(bitbang, 1);
mii_delay(bitbang);
/* send the PHY address */
for (j = 0; j < 5; j++) {
mdc(bitbang, 0);
mdio(bitbang, (addr & 0x10) != 0);
mii_delay(bitbang);
mdc(bitbang, 1);
mii_delay(bitbang);
addr <<= 1;
}
/* send the register address */
for (j = 0; j < 5; j++) {
mdc(bitbang, 0);
mdio(bitbang, (reg & 0x10) != 0);
mii_delay(bitbang);
mdc(bitbang, 1);
mii_delay(bitbang);
reg <<= 1;
}
}
static int fs_enet_mii_bb_read(struct mii_bus *bus , int phy_id, int location)
{
u16 rdreg;
int ret, j;
u8 addr = phy_id & 0xff;
u8 reg = location & 0xff;
struct bb_info* bitbang = bus->priv;
bitbang_pre(bitbang, 1, addr, reg);
/* tri-state our MDIO I/O pin so we can read */
mdc(bitbang, 0);
mdio_tristate(bitbang);
mii_delay(bitbang);
mdc(bitbang, 1);
mii_delay(bitbang);
/* check the turnaround bit: the PHY should be driving it to zero */
if (mdio_read(bitbang) != 0) {
/* PHY didn't drive TA low */
for (j = 0; j < 32; j++) {
mdc(bitbang, 0);
mii_delay(bitbang);
mdc(bitbang, 1);
mii_delay(bitbang);
}
ret = -1;
goto out;
}
mdc(bitbang, 0);
mii_delay(bitbang);
/* read 16 bits of register data, MSB first */
rdreg = 0;
for (j = 0; j < 16; j++) {
mdc(bitbang, 1);
mii_delay(bitbang);
rdreg <<= 1;
rdreg |= mdio_read(bitbang);
mdc(bitbang, 0);
mii_delay(bitbang);
}
mdc(bitbang, 1);
mii_delay(bitbang);
mdc(bitbang, 0);
mii_delay(bitbang);
mdc(bitbang, 1);
mii_delay(bitbang);
ret = rdreg;
out:
return ret;
}
static int fs_enet_mii_bb_write(struct mii_bus *bus, int phy_id, int location, u16 val)
{
int j;
struct bb_info* bitbang = bus->priv;
u8 addr = phy_id & 0xff;
u8 reg = location & 0xff;
u16 value = val & 0xffff;
bitbang_pre(bitbang, 0, addr, reg);
/* send the turnaround (10) */
mdc(bitbang, 0);
mdio(bitbang, 1);
mii_delay(bitbang);
mdc(bitbang, 1);
mii_delay(bitbang);
mdc(bitbang, 0);
mdio(bitbang, 0);
mii_delay(bitbang);
mdc(bitbang, 1);
mii_delay(bitbang);
/* write 16 bits of register data, MSB first */
for (j = 0; j < 16; j++) {
mdc(bitbang, 0);
mdio(bitbang, (value & 0x8000) != 0);
mii_delay(bitbang);
mdc(bitbang, 1);
mii_delay(bitbang);
value <<= 1;
}
/*
* Tri-state the MDIO line.
*/
mdio_tristate(bitbang);
mdc(bitbang, 0);
mii_delay(bitbang);
mdc(bitbang, 1);
mii_delay(bitbang);
return 0;
}
static int fs_enet_mii_bb_reset(struct mii_bus *bus)
{
/*nothing here - dunno how to reset it*/
return 0;
}
static int fs_mii_bitbang_init(struct bb_info *bitbang, struct fs_mii_bb_platform_info* fmpi)
{
int r;
bitbang->delay = fmpi->delay;
r = bitbang_prep_bit(&bitbang->mdio_dir,
&bitbang->mdio_dir_msk,
&fmpi->mdio_dir);
if (r != 0)
return r;
r = bitbang_prep_bit(&bitbang->mdio_dat,
&bitbang->mdio_dat_msk,
&fmpi->mdio_dat);
if (r != 0)
return r;
r = bitbang_prep_bit(&bitbang->mdc_dat,
&bitbang->mdc_msk,
&fmpi->mdc_dat);
if (r != 0)
return r;
return 0;
}
static int __devinit fs_enet_mdio_probe(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
struct fs_mii_bb_platform_info *pdata;
struct mii_bus *new_bus;
struct bb_info *bitbang;
int err = 0;
if (NULL == dev)
return -EINVAL;
new_bus = kzalloc(sizeof(struct mii_bus), GFP_KERNEL);
if (NULL == new_bus)
return -ENOMEM;
bitbang = kzalloc(sizeof(struct bb_info), GFP_KERNEL);
if (NULL == bitbang)
return -ENOMEM;
new_bus->name = "BB MII Bus",
new_bus->read = &fs_enet_mii_bb_read,
new_bus->write = &fs_enet_mii_bb_write,
new_bus->reset = &fs_enet_mii_bb_reset,
new_bus->id = pdev->id;
new_bus->phy_mask = ~0x9;
pdata = (struct fs_mii_bb_platform_info *)pdev->dev.platform_data;
if (NULL == pdata) {
printk(KERN_ERR "gfar mdio %d: Missing platform data!\n", pdev->id);
return -ENODEV;
}
/*set up workspace*/
fs_mii_bitbang_init(bitbang, pdata);
new_bus->priv = bitbang;
new_bus->irq = pdata->irq;
new_bus->dev = dev;
dev_set_drvdata(dev, new_bus);
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:
kfree(bitbang);
kfree(new_bus);
return err;
}
static int fs_enet_mdio_remove(struct device *dev)
{
struct mii_bus *bus = dev_get_drvdata(dev);
mdiobus_unregister(bus);
dev_set_drvdata(dev, NULL);
iounmap((void *) (&bus->priv));
bus->priv = NULL;
kfree(bus);
return 0;
}
static struct device_driver fs_enet_bb_mdio_driver = {
.name = "fsl-bb-mdio",
.bus = &platform_bus_type,
.probe = fs_enet_mdio_probe,
.remove = fs_enet_mdio_remove,
};
int fs_enet_mdio_bb_init(void)
{
return driver_register(&fs_enet_bb_mdio_driver);
}
void fs_enet_mdio_bb_exit(void)
{
driver_unregister(&fs_enet_bb_mdio_driver);
}