freebsd-skq/sys/dev/etherswitch/mdio.c
Adrian Chadd 4574da7fee Bring over the first part of the etherswitch framework - an MDIO bus and
MDIO/MII rendezvous proxy.

* Add an 'mdio' bus, which is the "IO" side of an MII bus (but by design
  can be anything which implements the underlying register access API.)
* Add 'miiproxy' and 'mdioproxy', which provides a rendezvous mechanism
  for MII busses to appear hanging off arbitrary busses (ie, that aren't
  necessarily a traditional looking MII bus.)

MII busses can now hang off anything that implements an mdiobus.

For the AR71xx SoC, there's one MDIO bus but two MII busses.  So to
properly support two or more real PHYs, this can be done:

  # arge0 MDIO bus - there's no arge1 MDIO bus for AR71xx
  hint.argemdio.0.at="nexus0"
  hint.argemdio.0.maddr=0x19000000
  hint.argemdio.0.msize=0x1000
  hint.argemdio.0.order=0

  # Create two mdioproxy instances
  hint.mdioproxy.0.at="mdio0"
  hint.mdioproxy.1.at="mdio0"

  # .. and with a follow-up patch
  hint.arge.0.mdio=mdioproxy0
  hint.arge.1.mdio=mdioproxy0

TODO:

* Do a sweep or two and add appropriate locking in mdio/mdioproxy/miiproxy.

Submitted by:	Stefan Bethke <stb@lassitu.de>
Reviewed by:	ray
2012-05-01 06:11:38 +00:00

118 lines
2.9 KiB
C

/*-
* Copyright (c) 2011-2012 Stefan Bethke.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#include <sys/param.h>
#include <sys/bus.h>
#include <sys/systm.h>
#include <dev/etherswitch/mdio.h>
#include "mdio_if.h"
static void
mdio_identify(driver_t *driver, device_t parent)
{
if (device_find_child(parent, mdio_driver.name, -1) == NULL)
BUS_ADD_CHILD(parent, 0, mdio_driver.name, -1);
}
static int
mdio_probe(device_t dev)
{
device_set_desc(dev, "MDIO");
return (BUS_PROBE_SPECIFIC);
}
static int
mdio_attach(device_t dev)
{
bus_generic_probe(dev);
bus_enumerate_hinted_children(dev);
return (bus_generic_attach(dev));
}
static int
mdio_detach(device_t dev)
{
bus_generic_detach(dev);
return (0);
}
static int
mdio_readreg(device_t dev, int phy, int reg)
{
return (MDIO_READREG(device_get_parent(dev), phy, reg));
}
static int
mdio_writereg(device_t dev, int phy, int reg, int val)
{
return (MDIO_WRITEREG(device_get_parent(dev), phy, reg, val));
}
static void
mdio_hinted_child(device_t dev, const char *name, int unit)
{
device_add_child(dev, name, unit);
}
static device_method_t mdio_methods[] = {
/* device interface */
DEVMETHOD(device_identify, mdio_identify),
DEVMETHOD(device_probe, mdio_probe),
DEVMETHOD(device_attach, mdio_attach),
DEVMETHOD(device_detach, mdio_detach),
DEVMETHOD(device_shutdown, bus_generic_shutdown),
/* bus interface */
DEVMETHOD(bus_add_child, device_add_child_ordered),
DEVMETHOD(bus_hinted_child, mdio_hinted_child),
/* MDIO access */
DEVMETHOD(mdio_readreg, mdio_readreg),
DEVMETHOD(mdio_writereg, mdio_writereg),
DEVMETHOD_END
};
driver_t mdio_driver = {
"mdio",
mdio_methods,
0
};
devclass_t mdio_devclass;