History log of /net/dsa/dsa.c
Revision Date Author Comments
ae439286a0dec99cc8029868243689b5b5f3ff75 24-Oct-2014 Andrew Lunn <andrew@lunn.ch> net: dsa: Error out on tagging protocol mismatches

If there is a mismatch between enabled tagging protocols and the
protocol the switch supports, error out, rather than continue with a
situation which is unlikely to work.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
cc: alexander.h.duyck@intel.com
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
e506d405ac7d34d03996c97ac68aa2ac010be64a 01-Oct-2014 Thierry Reding <treding@nvidia.com> net: dsa: Fix build warning for !PM_SLEEP

The dsa_switch_suspend() and dsa_switch_resume() functions are only used
when PM_SLEEP is enabled, so they need #ifdef CONFIG_PM_SLEEP protection
to avoid a compiler warning.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2446254915a7d6f08bba9a755a34cc0402880472 19-Sep-2014 Florian Fainelli <f.fainelli@gmail.com> net: dsa: allow switch drivers to implement suspend/resume hooks

Add an abstraction layer to suspend/resume switch devices, doing the
following split:

- suspend/resume the slave network devices and their corresponding PHY
devices
- suspend/resume the switch hardware using switch driver callbacks

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
c1f570a6abc192f047550743f9957b617af605af 15-Sep-2014 Florian Fainelli <f.fainelli@gmail.com> net: dsa: fix mii_bus to host_dev replacement

dsa_of_probe() still used cd->mii_bus instead of cd->host_dev when
building with CONFIG_OF=y. Fix this by making the replacement here as
well.

Fixes: b4d2394d01b ("dsa: Replace mii_bus with a generic host device")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
b4d2394d01bc642e95b2cba956d908423c1bef77 15-Sep-2014 Alexander Duyck <alexander.h.duyck@intel.com> dsa: Replace mii_bus with a generic host device

This change makes it so that instead of passing and storing a mii_bus we
instead pass and store a host_dev. From there we can test to determine the
exact type of device, and can verify it is the correct device for our switch.

So for example it would be possible to pass a device pointer from a pci_dev
and instead of checking for a PHY ID we could check for a vendor and/or device
ID.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
5075314e4e4b559cc37675ad8a721a89bccd6284 15-Sep-2014 Alexander Duyck <alexander.h.duyck@intel.com> dsa: Split ops up, and avoid assigning tag_protocol and receive separately

This change addresses several issues.

First, it was possible to set tag_protocol without setting the ops pointer.
To correct that I have reordered things so that rcv is now populated before
we set tag_protocol.

Second, it didn't make much sense to keep setting the device ops each time a
new slave was registered. So by moving the receive portion out into root
switch initialization that issue should be addressed.

Third, I wanted to avoid sending tags if the rcv pointer was not registered
so I changed the tag check to verify if the rcv function pointer is set on
the root tree. If it is then we start sending DSA tagged frames.

Finally I split the device ops pointer in the structures into two spots. I
placed the rcv function pointer in the root switch since this makes it
easiest to access from there, and I placed the xmit function pointer in the
slave for the same reason.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
61b7363ffa48b36e2ff086c2d2524e40d3766571 29-Aug-2014 Florian Fainelli <f.fainelli@gmail.com> net: dsa: make dsa_pack_type static

net/dsa/dsa.c:624:20: sparse: symbol 'dsa_pack_type' was not declared.
Should it be static?

Fixes: 3e8a72d1dae374 ("net: dsa: reduce number of protocol hooks")
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
246d7f773c13cac3e3ab1609fd4ffee520242c63 28-Aug-2014 Florian Fainelli <f.fainelli@gmail.com> net: dsa: add Broadcom SF2 switch driver

Add support for the Broadcom Starfigther 2 switch chip using a DSA
driver. This switch driver supports the following features:

- configuration of the external switch port interface: MII, RevMII,
RGMII and RGMII_NO_ID are supported
- support for the per-port MIB counters
- support for link interrupts for special ports (e.g: MoCA)
- powering up/down of switch memories to conserve power when ports are
unused

Finally, update the compatible property for the DSA core code to match
our switch top-level compatible node.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
0d8bcdd383b8865e752a7e8edb4712c2e3902052 28-Aug-2014 Florian Fainelli <f.fainelli@gmail.com> net: dsa: allow for more complex PHY setups

Modify the DSA slave interface to be bound to an arbitray PHY, not just
the ones that are available as child PHY devices of the switch MDIO bus.

This allows us for instance to have external PHYs connected to a
separate MDIO bus, but yet also connected to a given switch port.

Under certain configurations, the physical port mask might not be a 1:1
mapping to the MII PHYs mask. This is the case, if e.g: Port 1 of the
switch is used and connects to a PHY at a MDIO address different than 1.

Introduce a phys_mii_mask variable which allows driver to implement and
divert their own MDIO read/writes operations for a subset of the MDIO
PHY addresses.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
bd47497a0171b96264927e3377254db13b9fe3e3 28-Aug-2014 Florian Fainelli <f.fainelli@gmail.com> net: dsa: retain a per-port device_node pointer

We will later use the per-port device_node pointer to fetch a bunch of
port-specific properties.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
fa981d9af82e08f316ed25ed43078f995cc4be0a 28-Aug-2014 Florian Fainelli <f.fainelli@gmail.com> net: dsa: provide a switch device device tree node pointer

We might need to fetch additional resources from the device tree node
pointer, such as register ranges or other properties. Keep a device_node
pointer around for this.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
3e8a72d1dae374cf6fc1dba97cec663585845ff9 28-Aug-2014 Florian Fainelli <f.fainelli@gmail.com> net: dsa: reduce number of protocol hooks

DSA is currently registering one packet_type function per EtherType it
needs to intercept in the receive path of a DSA-enabled Ethernet device.
Right now we have three of them: trailer, DSA and eDSA, and there might
be more in the future, this will not scale to the addition of new
protocols.

This patch proceeds with adding a new layer of abstraction and two new
functions:

dsa_switch_rcv() which will dispatch into the tag-protocol specific
receive function implemented by net/dsa/tag_*.c

dsa_slave_xmit() which will dispatch into the tag-protocol specific
transmit function implemented by net/dsa/tag_*.c

When we do create the per-port slave network devices, we iterate over
the switch protocol to assign the DSA-specific receive and transmit
operations.

A new fake ethertype value is used: ETH_P_XDSA to illustrate the fact
that this is no longer going to look like ETH_P_DSA or ETH_P_TRAILER
like it used to be.

This allows us to greatly simplify the check in eth_type_trans() and
always override the skb->protocol with ETH_P_XDSA for Ethernet switches
tagged protocol, while also reducing the number repetitive slave
netdevice_ops assignments.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
1f74714f1e34a84fe4ef2a6d9b76c20794fb5dcf 23-Jun-2014 Fabian Frederick <fabf@skynet.be> net/dsa/dsa.c: remove unnecessary null test before kfree

Fix checkpatch warning:
WARNING: kfree(NULL) is safe this check is probably not required

Cc: "David S. Miller" <davem@davemloft.net>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: netdev@vger.kernel.org
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
d1c0b471b340f43fa857d19150e029257d7bb475 16-May-2014 Fabian Godehardt <fg@emlix.com> net/dsa/dsa.c: increment chip_index during of_node handling on dsa_of_probe()

Adding more than one chip on device-tree currently causes the probing
routine to always use the first chips data pointer.

Signed-off-by: Fabian Godehardt <fg@emlix.com>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
5f64a7dbf593c2317f132c8252d04cdfe8d4b104 25-Mar-2013 Florian Fainelli <florian@openwrt.org> dsa: fix freeing of sparse port allocation

If we have defined a sparse port allocation which is non-contiguous and
contains gaps, the code freeing port_names will just stop when it
encouters a first NULL port_names, which is not right, we should iterate
over all possible number of ports (DSA_MAX_PORTS) until we are done.

Signed-off-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
21168245031062212c0b805d0bd466ee6dd4a16f 25-Mar-2013 Florian Fainelli <florian@openwrt.org> dsa: factor freeing of dsa_platform_data

This patch factors the freeing of the struct dsa_platform_data
manipulated by the driver identically in two places to a single
function.

Signed-off-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
5e95329b701c4edf6c4d72487ec0369fa148c0bd 22-Mar-2013 Florian Fainelli <florian@openwrt.org> dsa: add device tree bindings to register DSA switches

This patch adds support for registering DSA switches using Device Tree
bindings. Note that we support programming the switch routing table even
though no in-tree user seems to require it. I tested this on Armada 370
with a Marvell 88E6172 (not supported by mainline yet).

Signed-off-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
f9bf5a2ca6cc331f32e3dd9cf16ced7215d0e6e8 21-Jan-2013 Florian Fainelli <florian@openwrt.org> dsa: make dsa_switch_setup check for valid port names

This patch changes dsa_switch_setup() to ensure that at least one valid
valid port name is specified and will bail out with an error in case we
walked the maximum number of port with a valid port name found.

Signed-off-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
43829731dd372d04d6706c51052b9dabab9ca356 20-Aug-2012 Tejun Heo <tj@kernel.org> workqueue: deprecate flush[_delayed]_work_sync()

flush[_delayed]_work_sync() are now spurious. Mark them deprecated
and convert all users to flush[_delayed]_work().

If you're cc'd and wondering what's going on: Now all workqueues are
non-reentrant and the regular flushes guarantee that the work item is
not pending or running on any CPU on return, so there's no reason to
use the sync flushes at all and they're going away.

This patch doesn't make any functional difference.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Mattia Dongili <malattia@linux.it>
Cc: Kent Yoder <key@linux.vnet.ibm.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Karsten Keil <isdn@linux-pingi.de>
Cc: Bryan Wu <bryan.wu@canonical.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Alasdair Kergon <agk@redhat.com>
Cc: Mauro Carvalho Chehab <mchehab@infradead.org>
Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: linux-wireless@vger.kernel.org
Cc: Anton Vorontsov <cbou@mail.ru>
Cc: Sangbeom Kim <sbkim73@samsung.com>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Petr Vandrovec <petr@vandrovec.name>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Avi Kivity <avi@redhat.com>
7df899c36cf09678bdef1824ce591ef4ac0e9864 25-Nov-2011 Ben Hutchings <ben@decadent.org.uk> dsa: Combine core and tagging code

These files have circular dependencies, so if we make DSA modular then
they must be built into the same module. Therefore, link them
together and merge their respective module init and exit functions.

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
ad293b8a218ca13a9ee3e3c98137fa301987577c 25-Nov-2011 Ben Hutchings <ben@decadent.org.uk> dsa: Export functions from core to modules

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
cf50dcc24f82a6dc2bce523eec2a979eb1b106e2 25-Nov-2011 Ben Hutchings <ben@decadent.org.uk> dsa: Change dsa_uses_{dsa, trailer}_tags() into inline functions

eth_type_trans() will use these functions if DSA is enabled, which
blocks building DSA as a module.

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
3a9a231d977222eea36eae091df2c358e03ac839 27-May-2011 Paul Gortmaker <paul.gortmaker@windriver.com> net: Fix files explicitly needing to include module.h

With calls to modular infrastructure, these files really
needs the full module.h header. Call it out so some of the
cleanups of implicit and unrequired includes elsewhere can be
cleaned up.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
577d6a7c3a0e273e115c65a148b71be6c1950f69 24-Jan-2011 Rusty Russell <rusty@rustcorp.com.au> module: fix missing semicolons in MODULE macro usage

You always needed them when you were a module, but the builtin versions
of the macros used to be more lenient.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
7f6b0db9f63ba423d989e29f6318fe7e68760421 24-Dec-2010 Tejun Heo <tj@kernel.org> net/dsa: don't use flush_scheduled_work()

flush_scheduled_work() is deprecated and scheduled to be removed.
Directly flush dst->link_poll_work on remove instead.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Lennert Buytenhek <buytenh@wantstofly.org>
5a0e3ad6af8660be21ca98a971cd00f331318c05 24-Mar-2010 Tejun Heo <tj@kernel.org> include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.

2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).

* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
e84665c9cb4db963393fafad6fefe5efdd7e4a09 20-Mar-2009 Lennert Buytenhek <buytenh@wantstofly.org> dsa: add switch chip cascading support

The initial version of the DSA driver only supported a single switch
chip per network interface, while DSA-capable switch chips can be
interconnected to form a tree of switch chips. This patch adds support
for multiple switch chips on a network interface.

An example topology for a 16-port device with an embedded CPU is as
follows:

+-----+ +--------+ +--------+
| |eth0 10| switch |9 10| switch |
| CPU +----------+ +-------+ |
| | | chip 0 | | chip 1 |
+-----+ +---++---+ +---++---+
|| ||
|| ||
||1000baseT ||1000baseT
||ports 1-8 ||ports 9-16

This requires a couple of interdependent changes in the DSA layer:

- The dsa platform driver data needs to be extended: there is still
only one netdevice per DSA driver instance (eth0 in the example
above), but each of the switch chips in the tree needs its own
mii_bus device pointer, MII management bus address, and port name
array. (include/net/dsa.h) The existing in-tree dsa users need
some small changes to deal with this. (arch/arm)

- The DSA and Ethertype DSA tagging modules need to be extended to
use the DSA device ID field on receive and demultiplex the packet
accordingly, and fill in the DSA device ID field on transmit
according to which switch chip the packet is heading to.
(net/dsa/tag_{dsa,edsa}.c)

- The concept of "CPU port", which is the switch chip port that the
CPU is connected to (port 10 on switch chip 0 in the example), needs
to be extended with the concept of "upstream port", which is the
port on the switch chip that will bring us one hop closer to the CPU
(port 10 for both switch chips in the example above).

- The dsa platform data needs to specify which ports on which switch
chips are links to other switch chips, so that we can enable DSA
tagging mode on them. (For inter-switch links, we always use
non-EtherType DSA tagging, since it has lower overhead. The CPU
link uses dsa or edsa tagging depending on what the 'root' switch
chip supports.) This is done by specifying "dsa" for the given
port in the port array.

- The dsa platform data needs to be extended with information on via
which port to reach any given switch chip from any given switch chip.
This info is specified via the per-switch chip data struct ->rtable[]
array, which gives the nexthop ports for each of the other switches
in the tree.

For the example topology above, the dsa platform data would look
something like this:

static struct dsa_chip_data sw[2] = {
{
.mii_bus = &foo,
.sw_addr = 1,
.port_names[0] = "p1",
.port_names[1] = "p2",
.port_names[2] = "p3",
.port_names[3] = "p4",
.port_names[4] = "p5",
.port_names[5] = "p6",
.port_names[6] = "p7",
.port_names[7] = "p8",
.port_names[9] = "dsa",
.port_names[10] = "cpu",
.rtable = (s8 []){ -1, 9, },
}, {
.mii_bus = &foo,
.sw_addr = 2,
.port_names[0] = "p9",
.port_names[1] = "p10",
.port_names[2] = "p11",
.port_names[3] = "p12",
.port_names[4] = "p13",
.port_names[5] = "p14",
.port_names[6] = "p15",
.port_names[7] = "p16",
.port_names[10] = "dsa",
.rtable = (s8 []){ 10, -1, },
},
},

static struct dsa_platform_data pd = {
.netdev = &foo,
.nr_switches = 2,
.sw = sw,
};

Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Tested-by: Gary Thomas <gary@mlbassoc.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
396138f03f4521c55ecc3a5dd75d4c56e6323244 07-Oct-2008 Lennert Buytenhek <buytenh@wantstofly.org> dsa: add support for Trailer tagging format

This adds support for the Trailer switch tagging format. This is
another tagging that doesn't explicitly mark tagged packets with a
distinct ethertype, so that we need to add a similar hack in the
receive path as for the Original DSA tagging format.

Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Tested-by: Byron Bradley <byron.bbradley@gmail.com>
Tested-by: Tim Ellis <tim.ellis@mac.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
cf85d08fdf4548ee46657ccfb7f9949a85145db5 07-Oct-2008 Lennert Buytenhek <buytenh@wantstofly.org> dsa: add support for original DSA tagging format

Most of the DSA switches currently in the field do not support the
Ethertype DSA tagging format that one of the previous patches added
support for, but only the original DSA tagging format.

The original DSA tagging format carries the same information as the
Ethertype DSA tagging format, but with the difference that it does not
have an ethertype field. In other words, when receiving a packet that
is tagged with an original DSA tag, there is no way of telling in
eth_type_trans() that this packet is in fact a DSA-tagged packet.

This patch adds a hook into eth_type_trans() which is only compiled in
if support for a switch chip that doesn't support Ethertype DSA is
selected, and which checks whether there is a DSA switch driver
instance attached to this network device which uses the old tag format.
If so, it sets the protocol field to ETH_P_DSA without looking at the
packet, so that the packet ends up in the right place.

Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Tested-by: Nicolas Pitre <nico@marvell.com>
Tested-by: Peter van Valderen <linux@ddcrew.com>
Tested-by: Dirk Teurlings <dirk@upexia.nl>
Signed-off-by: David S. Miller <davem@davemloft.net>
91da11f870f00a3322b81c73042291d7f0be5a17 07-Oct-2008 Lennert Buytenhek <buytenh@wantstofly.org> net: Distributed Switch Architecture protocol support

Distributed Switch Architecture is a protocol for managing hardware
switch chips. It consists of a set of MII management registers and
commands to configure the switch, and an ethernet header format to
signal which of the ports of the switch a packet was received from
or is intended to be sent to.

The switches that this driver supports are typically embedded in
access points and routers, and a typical setup with a DSA switch
looks something like this:

+-----------+ +-----------+
| | RGMII | |
| +-------+ +------ 1000baseT MDI ("WAN")
| | | 6-port +------ 1000baseT MDI ("LAN1")
| CPU | | ethernet +------ 1000baseT MDI ("LAN2")
| |MIImgmt| switch +------ 1000baseT MDI ("LAN3")
| +-------+ w/5 PHYs +------ 1000baseT MDI ("LAN4")
| | | |
+-----------+ +-----------+

The switch driver presents each port on the switch as a separate
network interface to Linux, polls the switch to maintain software
link state of those ports, forwards MII management interface
accesses to those network interfaces (e.g. as done by ethtool) to
the switch, and exposes the switch's hardware statistics counters
via the appropriate Linux kernel interfaces.

This initial patch supports the MII management interface register
layout of the Marvell 88E6123, 88E6161 and 88E6165 switch chips, and
supports the "Ethertype DSA" packet tagging format.

(There is no officially registered ethertype for the Ethertype DSA
packet format, so we just grab a random one. The ethertype to use
is programmed into the switch, and the switch driver uses the value
of ETH_P_EDSA for this, so this define can be changed at any time in
the future if the one we chose is allocated to another protocol or
if Ethertype DSA gets its own officially registered ethertype, and
everything will continue to work.)

Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Tested-by: Nicolas Pitre <nico@marvell.com>
Tested-by: Byron Bradley <byron.bbradley@gmail.com>
Tested-by: Tim Ellis <tim.ellis@mac.com>
Tested-by: Peter van Valderen <linux@ddcrew.com>
Tested-by: Dirk Teurlings <dirk@upexia.nl>
Signed-off-by: David S. Miller <davem@davemloft.net>