linux-stable-rt/net/dsa/dsa.c

435 lines
9.2 KiB
C

/*
* net/dsa/dsa.c - Hardware switch handling
* Copyright (c) 2008-2009 Marvell Semiconductor
*
* 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/list.h>
#include <linux/netdevice.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <net/dsa.h>
#include "dsa_priv.h"
char dsa_driver_version[] = "0.1";
/* switch driver registration ***********************************************/
static DEFINE_MUTEX(dsa_switch_drivers_mutex);
static LIST_HEAD(dsa_switch_drivers);
void register_switch_driver(struct dsa_switch_driver *drv)
{
mutex_lock(&dsa_switch_drivers_mutex);
list_add_tail(&drv->list, &dsa_switch_drivers);
mutex_unlock(&dsa_switch_drivers_mutex);
}
void unregister_switch_driver(struct dsa_switch_driver *drv)
{
mutex_lock(&dsa_switch_drivers_mutex);
list_del_init(&drv->list);
mutex_unlock(&dsa_switch_drivers_mutex);
}
static struct dsa_switch_driver *
dsa_switch_probe(struct mii_bus *bus, int sw_addr, char **_name)
{
struct dsa_switch_driver *ret;
struct list_head *list;
char *name;
ret = NULL;
name = NULL;
mutex_lock(&dsa_switch_drivers_mutex);
list_for_each(list, &dsa_switch_drivers) {
struct dsa_switch_driver *drv;
drv = list_entry(list, struct dsa_switch_driver, list);
name = drv->probe(bus, sw_addr);
if (name != NULL) {
ret = drv;
break;
}
}
mutex_unlock(&dsa_switch_drivers_mutex);
*_name = name;
return ret;
}
/* basic switch operations **************************************************/
static struct dsa_switch *
dsa_switch_setup(struct dsa_switch_tree *dst, int index,
struct device *parent, struct mii_bus *bus)
{
struct dsa_chip_data *pd = dst->pd->chip + index;
struct dsa_switch_driver *drv;
struct dsa_switch *ds;
int ret;
char *name;
int i;
/*
* Probe for switch model.
*/
drv = dsa_switch_probe(bus, pd->sw_addr, &name);
if (drv == NULL) {
printk(KERN_ERR "%s[%d]: could not detect attached switch\n",
dst->master_netdev->name, index);
return ERR_PTR(-EINVAL);
}
printk(KERN_INFO "%s[%d]: detected a %s switch\n",
dst->master_netdev->name, index, name);
/*
* Allocate and initialise switch state.
*/
ds = kzalloc(sizeof(*ds) + drv->priv_size, GFP_KERNEL);
if (ds == NULL)
return ERR_PTR(-ENOMEM);
ds->dst = dst;
ds->index = index;
ds->pd = dst->pd->chip + index;
ds->drv = drv;
ds->master_mii_bus = bus;
/*
* Validate supplied switch configuration.
*/
for (i = 0; i < DSA_MAX_PORTS; i++) {
char *name;
name = pd->port_names[i];
if (name == NULL)
continue;
if (!strcmp(name, "cpu")) {
if (dst->cpu_switch != -1) {
printk(KERN_ERR "multiple cpu ports?!\n");
ret = -EINVAL;
goto out;
}
dst->cpu_switch = index;
dst->cpu_port = i;
} else if (!strcmp(name, "dsa")) {
ds->dsa_port_mask |= 1 << i;
} else {
ds->phys_port_mask |= 1 << i;
}
}
/*
* If the CPU connects to this switch, set the switch tree
* tagging protocol to the preferred tagging format of this
* switch.
*/
if (ds->dst->cpu_switch == index)
ds->dst->tag_protocol = drv->tag_protocol;
/*
* Do basic register setup.
*/
ret = drv->setup(ds);
if (ret < 0)
goto out;
ret = drv->set_addr(ds, dst->master_netdev->dev_addr);
if (ret < 0)
goto out;
ds->slave_mii_bus = mdiobus_alloc();
if (ds->slave_mii_bus == NULL) {
ret = -ENOMEM;
goto out;
}
dsa_slave_mii_bus_init(ds);
ret = mdiobus_register(ds->slave_mii_bus);
if (ret < 0)
goto out_free;
/*
* Create network devices for physical switch ports.
*/
for (i = 0; i < DSA_MAX_PORTS; i++) {
struct net_device *slave_dev;
if (!(ds->phys_port_mask & (1 << i)))
continue;
slave_dev = dsa_slave_create(ds, parent, i, pd->port_names[i]);
if (slave_dev == NULL) {
printk(KERN_ERR "%s[%d]: can't create dsa "
"slave device for port %d(%s)\n",
dst->master_netdev->name,
index, i, pd->port_names[i]);
continue;
}
ds->ports[i] = slave_dev;
}
return ds;
out_free:
mdiobus_free(ds->slave_mii_bus);
out:
kfree(ds);
return ERR_PTR(ret);
}
static void dsa_switch_destroy(struct dsa_switch *ds)
{
}
/* hooks for ethertype-less tagging formats *********************************/
/*
* The original DSA tag format and some other tag formats have no
* ethertype, which means that we need to add a little hack to the
* networking receive path to make sure that received frames get
* the right ->protocol assigned to them when one of those tag
* formats is in use.
*/
bool dsa_uses_dsa_tags(void *dsa_ptr)
{
struct dsa_switch_tree *dst = dsa_ptr;
return !!(dst->tag_protocol == htons(ETH_P_DSA));
}
bool dsa_uses_trailer_tags(void *dsa_ptr)
{
struct dsa_switch_tree *dst = dsa_ptr;
return !!(dst->tag_protocol == htons(ETH_P_TRAILER));
}
/* link polling *************************************************************/
static void dsa_link_poll_work(struct work_struct *ugly)
{
struct dsa_switch_tree *dst;
int i;
dst = container_of(ugly, struct dsa_switch_tree, link_poll_work);
for (i = 0; i < dst->pd->nr_chips; i++) {
struct dsa_switch *ds = dst->ds[i];
if (ds != NULL && ds->drv->poll_link != NULL)
ds->drv->poll_link(ds);
}
mod_timer(&dst->link_poll_timer, round_jiffies(jiffies + HZ));
}
static void dsa_link_poll_timer(unsigned long _dst)
{
struct dsa_switch_tree *dst = (void *)_dst;
schedule_work(&dst->link_poll_work);
}
/* platform driver init and cleanup *****************************************/
static int dev_is_class(struct device *dev, void *class)
{
if (dev->class != NULL && !strcmp(dev->class->name, class))
return 1;
return 0;
}
static struct device *dev_find_class(struct device *parent, char *class)
{
if (dev_is_class(parent, class)) {
get_device(parent);
return parent;
}
return device_find_child(parent, class, dev_is_class);
}
static struct mii_bus *dev_to_mii_bus(struct device *dev)
{
struct device *d;
d = dev_find_class(dev, "mdio_bus");
if (d != NULL) {
struct mii_bus *bus;
bus = to_mii_bus(d);
put_device(d);
return bus;
}
return NULL;
}
static struct net_device *dev_to_net_device(struct device *dev)
{
struct device *d;
d = dev_find_class(dev, "net");
if (d != NULL) {
struct net_device *nd;
nd = to_net_dev(d);
dev_hold(nd);
put_device(d);
return nd;
}
return NULL;
}
static int dsa_probe(struct platform_device *pdev)
{
static int dsa_version_printed;
struct dsa_platform_data *pd = pdev->dev.platform_data;
struct net_device *dev;
struct dsa_switch_tree *dst;
int i;
if (!dsa_version_printed++)
printk(KERN_NOTICE "Distributed Switch Architecture "
"driver version %s\n", dsa_driver_version);
if (pd == NULL || pd->netdev == NULL)
return -EINVAL;
dev = dev_to_net_device(pd->netdev);
if (dev == NULL)
return -EINVAL;
if (dev->dsa_ptr != NULL) {
dev_put(dev);
return -EEXIST;
}
dst = kzalloc(sizeof(*dst), GFP_KERNEL);
if (dst == NULL) {
dev_put(dev);
return -ENOMEM;
}
platform_set_drvdata(pdev, dst);
dst->pd = pd;
dst->master_netdev = dev;
dst->cpu_switch = -1;
dst->cpu_port = -1;
for (i = 0; i < pd->nr_chips; i++) {
struct mii_bus *bus;
struct dsa_switch *ds;
bus = dev_to_mii_bus(pd->chip[i].mii_bus);
if (bus == NULL) {
printk(KERN_ERR "%s[%d]: no mii bus found for "
"dsa switch\n", dev->name, i);
continue;
}
ds = dsa_switch_setup(dst, i, &pdev->dev, bus);
if (IS_ERR(ds)) {
printk(KERN_ERR "%s[%d]: couldn't create dsa switch "
"instance (error %ld)\n", dev->name, i,
PTR_ERR(ds));
continue;
}
dst->ds[i] = ds;
if (ds->drv->poll_link != NULL)
dst->link_poll_needed = 1;
}
/*
* If we use a tagging format that doesn't have an ethertype
* field, make sure that all packets from this point on get
* sent to the tag format's receive function.
*/
wmb();
dev->dsa_ptr = (void *)dst;
if (dst->link_poll_needed) {
INIT_WORK(&dst->link_poll_work, dsa_link_poll_work);
init_timer(&dst->link_poll_timer);
dst->link_poll_timer.data = (unsigned long)dst;
dst->link_poll_timer.function = dsa_link_poll_timer;
dst->link_poll_timer.expires = round_jiffies(jiffies + HZ);
add_timer(&dst->link_poll_timer);
}
return 0;
}
static int dsa_remove(struct platform_device *pdev)
{
struct dsa_switch_tree *dst = platform_get_drvdata(pdev);
int i;
if (dst->link_poll_needed)
del_timer_sync(&dst->link_poll_timer);
flush_scheduled_work();
for (i = 0; i < dst->pd->nr_chips; i++) {
struct dsa_switch *ds = dst->ds[i];
if (ds != NULL)
dsa_switch_destroy(ds);
}
return 0;
}
static void dsa_shutdown(struct platform_device *pdev)
{
}
static struct platform_driver dsa_driver = {
.probe = dsa_probe,
.remove = dsa_remove,
.shutdown = dsa_shutdown,
.driver = {
.name = "dsa",
.owner = THIS_MODULE,
},
};
static int __init dsa_init_module(void)
{
return platform_driver_register(&dsa_driver);
}
module_init(dsa_init_module);
static void __exit dsa_cleanup_module(void)
{
platform_driver_unregister(&dsa_driver);
}
module_exit(dsa_cleanup_module);
MODULE_AUTHOR("Lennert Buytenhek <buytenh@wantstofly.org>")
MODULE_DESCRIPTION("Driver for Distributed Switch Architecture switch chips");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:dsa");