linux/drivers/net/ibm_newemac/tah.c
David Gibson 1d3bb99648 Device tree aware EMAC driver
Based on BenH's earlier work, this is a new version of the EMAC driver
for the built-in ethernet found on PowerPC 4xx embedded CPUs.  The
same ASIC is also found in the Axon bridge chip.  This new version is
designed to work in the arch/powerpc tree, using the device tree to
probe the device, rather than the old and ugly arch/ppc OCP layer.

This driver is designed to sit alongside the old driver (that lies in
drivers/net/ibm_emac and this one in drivers/net/ibm_newemac).  The
old driver is left in place to support arch/ppc until arch/ppc itself
reaches its final demise (not too long now, with luck).

This driver still has a number of things that could do with cleaning
up, but I think they can be fixed up after merging.  Specifically:
	- Should be adjusted to properly use the dma mapping API.
Axon needs this.
	- Probe logic needs reworking, in conjuction with the general
probing code for of_platform devices.  The dependencies here between
EMAC, MAL, ZMII etc. make this complicated.  At present, it usually
works, because we initialize and register the sub-drivers before the
EMAC driver itself, and (being in driver code) runs after the devices
themselves have been instantiated from the device tree.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-10-10 16:51:52 -07:00

174 lines
3.8 KiB
C

/*
* drivers/net/ibm_newemac/tah.c
*
* Driver for PowerPC 4xx on-chip ethernet controller, TAH support.
*
* Copyright 2004 MontaVista Software, Inc.
* Matt Porter <mporter@kernel.crashing.org>
*
* Copyright (c) 2005 Eugene Surovegin <ebs@ebshome.net>
*
* 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 <asm/io.h>
#include "emac.h"
#include "core.h"
int __devinit tah_attach(struct of_device *ofdev, int channel)
{
struct tah_instance *dev = dev_get_drvdata(&ofdev->dev);
mutex_lock(&dev->lock);
/* Reset has been done at probe() time... nothing else to do for now */
++dev->users;
mutex_unlock(&dev->lock);
return 0;
}
void __devexit tah_detach(struct of_device *ofdev, int channel)
{
struct tah_instance *dev = dev_get_drvdata(&ofdev->dev);
mutex_lock(&dev->lock);
--dev->users;
mutex_unlock(&dev->lock);
}
void tah_reset(struct of_device *ofdev)
{
struct tah_instance *dev = dev_get_drvdata(&ofdev->dev);
struct tah_regs *p = dev->base;
int n;
/* Reset TAH */
out_be32(&p->mr, TAH_MR_SR);
n = 100;
while ((in_be32(&p->mr) & TAH_MR_SR) && n)
--n;
if (unlikely(!n))
printk(KERN_ERR "%s: reset timeout\n", ofdev->node->full_name);
/* 10KB TAH TX FIFO accomodates the max MTU of 9000 */
out_be32(&p->mr,
TAH_MR_CVR | TAH_MR_ST_768 | TAH_MR_TFS_10KB | TAH_MR_DTFP |
TAH_MR_DIG);
}
int tah_get_regs_len(struct of_device *ofdev)
{
return sizeof(struct emac_ethtool_regs_subhdr) +
sizeof(struct tah_regs);
}
void *tah_dump_regs(struct of_device *ofdev, void *buf)
{
struct tah_instance *dev = dev_get_drvdata(&ofdev->dev);
struct emac_ethtool_regs_subhdr *hdr = buf;
struct tah_regs *regs = (struct tah_regs *)(hdr + 1);
hdr->version = 0;
hdr->index = 0; /* for now, are there chips with more than one
* zmii ? if yes, then we'll add a cell_index
* like we do for emac
*/
memcpy_fromio(regs, dev->base, sizeof(struct tah_regs));
return regs + 1;
}
static int __devinit tah_probe(struct of_device *ofdev,
const struct of_device_id *match)
{
struct device_node *np = ofdev->node;
struct tah_instance *dev;
struct resource regs;
int rc;
rc = -ENOMEM;
dev = kzalloc(sizeof(struct tah_instance), GFP_KERNEL);
if (dev == NULL) {
printk(KERN_ERR "%s: could not allocate TAH device!\n",
np->full_name);
goto err_gone;
}
mutex_init(&dev->lock);
dev->ofdev = ofdev;
rc = -ENXIO;
if (of_address_to_resource(np, 0, &regs)) {
printk(KERN_ERR "%s: Can't get registers address\n",
np->full_name);
goto err_free;
}
rc = -ENOMEM;
dev->base = (struct tah_regs *)ioremap(regs.start,
sizeof(struct tah_regs));
if (dev->base == NULL) {
printk(KERN_ERR "%s: Can't map device registers!\n",
np->full_name);
goto err_free;
}
/* Initialize TAH and enable IPv4 checksum verification, no TSO yet */
tah_reset(ofdev);
printk(KERN_INFO
"TAH %s initialized\n", ofdev->node->full_name);
wmb();
dev_set_drvdata(&ofdev->dev, dev);
return 0;
err_free:
kfree(dev);
err_gone:
return rc;
}
static int __devexit tah_remove(struct of_device *ofdev)
{
struct tah_instance *dev = dev_get_drvdata(&ofdev->dev);
dev_set_drvdata(&ofdev->dev, NULL);
WARN_ON(dev->users != 0);
iounmap(dev->base);
kfree(dev);
return 0;
}
static struct of_device_id tah_match[] =
{
{
.type = "tah",
},
{},
};
static struct of_platform_driver tah_driver = {
.name = "emac-tah",
.match_table = tah_match,
.probe = tah_probe,
.remove = tah_remove,
};
int __init tah_init(void)
{
return of_register_platform_driver(&tah_driver);
}
void tah_exit(void)
{
of_unregister_platform_driver(&tah_driver);
}