Some platforms have special bank registers which might be used to
select the correct clock or the right mode for Media Indepent Interface
controllers. Sometimes, it is also required to activate vcc regulators
in the right order to supply the ethernet controller at the right time.
This patch is an architecture refactoring of the arc-emac device driver.
It adds a new software design which allows to add specific platform
glue layer. Each platform has now its own module which performs custom
initialization and remove for the target and then calls to the
core driver.
Signed-off-by: Romain Perier <romain.perier@gmail.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
This is an api changes for the emac_mdio.c module.
It will be required later when arc_emac_probe/arc_emac_remove
will no longer use 'struct platform_device'.
Signed-off-by: Romain Perier <romain.perier@gmail.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
This is a preparation of an api changes for the emac_main.c module.
The involved functions are arc_emac_probe and arc_emac_remove.
Signed-off-by: Romain Perier <romain.perier@gmail.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Incorrect checking of array instead of array contents in panic_dump
flow - results of commit e261199872 ("bnx2x: Safe bnx2x_panic_dump()").
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Yuval Mintz <Yuval.Mintz@qlogic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Replace the strncpy with strlcpy, and use sizeof to determine the
length.
Signed-off-by: Hayes Wang <hayeswang@realtek.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Missing documentation for gc_thresh2 sysctl.
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
bnx2x uses ptp functions, so it should select the provider of
those functions (PTP_1588_CLOCK). Fixes these build errors:
drivers/built-in.o: In function `__bnx2x_remove':
/home/jim/linux/drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c:13409:
undefined reference to `ptp_clock_unregister'
drivers/built-in.o: In function `bnx2x_register_phc':
/home/jim/linux/drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c:13202:
undefined reference to `ptp_clock_register'
drivers/built-in.o: In function `bnx2x_get_ts_info':
/home/jim/linux/drivers/net/ethernet/broadcom/bnx2x/bnx2x_ethtool.c:3498:
undefined reference to `ptp_clock_index'
Reported-by: Jim Davis <jim.epost@gmail.com>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
When one tries to add eth as a port into team and that eth is already in
use by other rx_handler device (macvlan, bond, bridge, ...) a bug in
team_port_add() causes that IFF_TEAM_PORT flag is set before rx_handler
is registered. In between, netdev nofifier is called and
team_device_event() sees IFF_TEAM_PORT and thinks that rx_handler_data
pointer is set to team_port. But it isn't.
Fix this by reordering rx_handler register and IFF_TEAM_PORT priv flag
set so it is very similar to how bonding does this.
Reported-by: Erik Hugne <erik.hugne@ericsson.com>
Fixes: 3d249d4ca7 "net: introduce ethernet teaming device"
Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>
'shift by register' operations are supported by eBPF interpreter, but were
accidently left out of x64 JIT compiler. Fix it and add a testcase.
Reported-by: Brendan Gregg <brendan.d.gregg@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Fixes: 622582786c ("net: filter: x86: internal BPF JIT")
Signed-off-by: David S. Miller <davem@davemloft.net>
Yuval Mintz says:
====================
bnx2x: `fixes' patch-series
This series contains mostly bug fixes, but never the less is intended
for `net-next' and not `net', as:
- Some of the fixes are quite insignificant [`VF clean statistics',
`ethtool -d might cause timeout in log'].
- Some only recently were submitted to `net-next' [`Fix timesync endianity'].
- Some are not usually compiled as part of the kernel [`Fix stop-on-error'].
Dave - please consider applying this series to `net-next'; If you prefer,
I can break this series into 2 parts [one for `net' and the other for
`net-next'] - but personally I don't see much benefit in it.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit eeed018cbf ("bnx2x: Add timestamping and PTP hardware clock support")
has a missing conversion to LE32, which will prevent the feature from working
on big endian machines.
Signed-off-by: Michal Kalderon <Michal.Kalderon@qlogic.com>
Signed-off-by: Yuval Mintz <Yuval.Mintz@qlogic.com>
Signed-off-by: Ariel Elior <Ariel.Elior@qlogic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This introduces 2 new relaxations in the bnx2x driver regarding GRO:
1. Don't prevent SW GRO if HW GRO is disabled.
2. If all aggregations are disabled, when GRO configuration changes
there's no need to perform an inner-reload [since it will have no
actual effect].
Signed-off-by: Dmitry Kravkov <Dmitry.Kravkov@qlogic.com>
Signed-off-by: Yuval Mintz <Yuval.Mintz@qlogic.com>
Signed-off-by: Ariel Elior <Ariel.Elior@qlogic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
During statistics initialization of a VF we need to clean its statistics.
Signed-off-by: Yuval Mintz <Yuval.Mintz@qlogic.com>
Signed-off-by: Ariel Elior <Ariel.Elior@qlogic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When STOP_ON_ERROR is set driver will not compile. Even if it did,
traffic will not pass without this patch as several fields which are
verified by FW/HW on the Tx path are not properly set.
Signed-off-by: Yuval Mintz <Yuval.Mintz@qlogic.com>
Signed-off-by: Ariel Elior <Ariel.Elior@qlogic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This changes slightly the set of registers read during `ethtool -d'.
Without this change, it's possible the HW will generate a grc Attention which
will be logged into system logs as `grc timeout'.
Signed-off-by: Dmitry Kravkov <Dmitry.Kravkov@qlogic.com>
Signed-off-by: Yuval Mintz <Yuval.Mintz@qlogic.com>
Signed-off-by: Ariel Elior <Ariel.Elior@qlogic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fixes: commit 690e36e726 (net: Allow raw buffers to be passed into the flow dissector)
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fixes: commit 690e36e726 (net: Allow raw buffers to be passed into the flow dissector)
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This implements the deferred tail pointer flush API for the ixgbe
driver. Similar version also proposed longer time ago by Alexander Duyck.
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
As reported by Jesper Dangaard Brouer, for high packet rates the
overhead of having another indirect call in the TX path is
non-trivial.
There is the indirect call itself, and then there is all of the
reloading of the state to refetch the tail pointer value and
then write the device register.
Move to a more passive scheme, which requires very light modifications
to the device drivers.
The signal is a new skb->xmit_more value, if it is non-zero it means
that more SKBs are pending to be transmitted on the same queue as the
current SKB. And therefore, the driver may elide the tail pointer
update.
Right now skb->xmit_more is always zero.
Signed-off-by: David S. Miller <davem@davemloft.net>
Amir Vadai says:
====================
Make is_kdump_kernel() accessible from modules
I'm re-spinning this patchset. At the begining it was suggested to use a
different name for the parameter, but at the end [3] the resolution was to
leave it as it is in this patch.
Drivers need to know if running from kdump kernel in order to change their
memory profile - since kdump environment is limited by available memory.
Currently there are drivers that are using reset_devices as suggested in [2].
In [2] it was suggested to use reset_devices, but the context was, to enable
driver to know when the hardware device is needed to be reset, and not if this
is a kdump environment. We think that is_kdump_kernel() is better suited to
select between different memory profiles.
The first patch in this patchset exports a needed symbol in order to make
is_kdump_kernel() accessible from the drivers. The rest of the patches change
from reset_devices to is_kdump_kernel() in 2 networking drivers.
The idea of this patchset was suggested by Vivek Goyal.
Tested (only build) and applied on top of commit 8fc54f6: ("net: use
reciprocal_scale() helper")
[1] - ea1c1af: ("net/mlx4_en: Reduce memory consumption on kdump kernel")
[2] - https://lkml.org/lkml/2011/1/27/341
[3] - http://www.spinics.net/lists/netdev/msg291492.html
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Use is_kdump_kernel() to detect kdump kernel, instead of
reset_devices.
CC: Ariel Elior <ariel.elior@qlogic.com>
CC: Michal Schmidt <mschmidt@redhat.com>
Signed-off-by: Amir Vadai <amirv@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use is_kdump_kernel() to detect kdump kernel, instead of reset_devices.
Signed-off-by: Amir Vadai <amirv@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In order to make is_kdump_kernel() accessible from modules, need to
make elfcorehdr_addr exported.
This was rejected in the past [1] because reset_devices was prefered in
that context (reseting the device in kdump kernel), but now there are
some network drivers that need to reduce memory usage when loaded from
a kdump kernel. And in that context, is_kdump_kernel() suits better.
[1] - https://lkml.org/lkml/2011/1/27/341
CC: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Amir Vadai <amirv@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This adds simple cleanups for stmmac, removing test we know is always
true, fixing whitespace, and moving code out of if().
Signed-off-by: Pavel Machek <pavel@denx.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
626: CHECK: Alignment should match open parenthesis
646: CHECK: Alignment should match open parenthesis
655: CHECK: Alignment should match open parenthesis
695: CHECK: Alignment should match open parenthesis
729: CHECK: Alignment should match open parenthesis
739: CHECK: Alignment should match open parenthesis
976: WARNING: externs should be avoided in .c files
1314: CHECK: Alignment should match open parenthesis
1358: WARNING: networking block comments don't use an empty /* line, use /* Comment...
1402: WARNING: networking block comments don't use an empty /* line, use /* Comment...
1521: CHECK: multiple assignments should be avoided
1775: CHECK: Alignment should match open parenthesis
1838: CHECK: multiple assignments should be avoided
1843: CHECK: multiple assignments should be avoided
1847: CHECK: multiple assignments should be avoided
1850: WARNING: Missing a blank line after declarations
1864: CHECK: Alignment should match open parenthesis
1872: CHECK: braces {} should be used on all arms of this statement
1906: CHECK: usleep_range is preferred over udelay
2865: WARNING: networking block comments don't use an empty /* line, use /* Comment...
3088: CHECK: Alignment should match open parenthesis
total: 0 errors, 5 warnings, 16 checks, 3567 lines checked
Signed-off-by: Hayes Wang <hayeswang@realtek.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Basic deferred TX queue flushing infrastructure.
Over time, and specifically and more recently at the Networking
Workshop during Kernel SUmmit in Chicago, we have discussed the idea
of having some way to optimize transmits of multiple TX packets at
a time.
There are several areas of overhead that could be amortized with such
schemes. One has to do with locking and transactional overhead, the
other has to do with device specific costs.
This patch set here is more aimed at device specific costs.
Typically a device queues up a packet in the TX queue and then has to
do something to have the device start processing that new entry.
Sometimes this is composed of doing an MMIO write to a "tail"
register, and in other cases it can involve something as expensive as
a hypervisor call.
The basic setup defined here is that when the driver supports deferred
TX queue flushing, ndo_start_xmit should no longer perform that
operation. Instead a new operation, ndo_xmit_flush, should do it.
I have converted IGB and virtio_net as example initial users. The IGB
conversion is tested, virtio_net is not but it does compile :-)
All ndo_start_xmit call sites have been abstracted behind a new helper
called netdev_start_xmit().
This just adds the infrastructure, it does not actually add any
instances of actually doing multiple ndo_start_xmit calls per
ndo_xmit_flush invocation.
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch makes no changes to the logic of the code but simply addresses
coding style issues as detected by checkpatch.
Both objdump and diff -w show no differences.
This patch removes some blank lines between the end of a function
definition and the EXPORT_SYMBOL_GPL macro in order to prevent
checkpatch warning that EXPORT_SYMBOL must immediately follow
a function.
Signed-off-by: Ian Morris <ipm@chirality.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch makes no changes to the logic of the code but simply addresses
coding style issues as detected by checkpatch.
Both objdump and diff -w show no differences.
This patch addresses structure definitions, specifically it cleanses the brace
placement and replaces spaces with tabs in a few places.
Signed-off-by: Ian Morris <ipm@chirality.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch makes no changes to the logic of the code but simply addresses
coding style issues as detected by checkpatch.
Both objdump and diff -w show no differences.
A number of items are addressed in this patch:
* Multiple spaces converted to tabs
* Spaces before tabs removed.
* Spaces in pointer typing cleansed (char *)foo etc.
* Remove space after sizeof
* Ensure spacing around comparators such as if statements.
Signed-off-by: Ian Morris <ipm@chirality.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
This cuts down the number of debug information spit out by
the driver.
Signed-off-by: Dariusz Marcinkiewicz <reksio@newterm.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch addresses a couple of minor items, mostly addesssing
prandom_bytes(): 1) prandom_bytes{,_state}() should use size_t
for length arguments, 2) We can use put_unaligned() when filling
the array instead of open coding it [ perhaps some archs will
further benefit from their own arch specific implementation when
GCC cannot make up for it ], 3) Fix a typo, 4) Better use unsigned
int as type for getting the arch seed, 5) Make use of
prandom_u32_max() for timer slack.
Regarding the change to put_unaligned(), callers of prandom_bytes()
which internally invoke prandom_bytes_state(), don't bother as
they expect the array to be filled randomly and don't have any
control of the internal state what-so-ever (that's also why we
have periodic reseeding there, etc), so they really don't care.
Now for the direct callers of prandom_bytes_state(), which
are solely located in test cases for MTD devices, that is,
drivers/mtd/tests/{oobtest.c,pagetest.c,subpagetest.c}:
These tests basically fill a test write-vector through
prandom_bytes_state() with an a-priori defined seed each time
and write that to a MTD device. Later on, they set up a read-vector
and read back that blocks from the device. So in the verification
phase, the write-vector is being re-setup [ so same seed and
prandom_bytes_state() called ], and then memcmp()'ed against the
read-vector to check if the data is the same.
Akinobu, Lothar and I also tested this patch and it runs through
the 3 relevant MTD test cases w/o any errors on the nandsim device
(simulator for MTD devs) for x86_64, ppc64, ARM (i.MX28, i.MX53
and i.MX6):
# modprobe nandsim first_id_byte=0x20 second_id_byte=0xac \
third_id_byte=0x00 fourth_id_byte=0x15
# modprobe mtd_oobtest dev=0
# modprobe mtd_pagetest dev=0
# modprobe mtd_subpagetest dev=0
We also don't have any users depending directly on a particular
result of the PRNG (except the PRNG self-test itself), and that's
just fine as it e.g. allowed us easily to do things like upgrading
from taus88 to taus113.
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Tested-by: Akinobu Mita <akinobu.mita@gmail.com>
Tested-by: Lothar Waßmann <LW@KARO-electronics.de>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Tom Herbert says:
====================
net: Checksum offload changes - Part V
I am working on overhauling RX checksum offload. Goals of this effort
are:
- Specify what exactly it means when driver returns CHECKSUM_UNNECESSARY
- Preserve CHECKSUM_COMPLETE through encapsulation layers
- Don't do skb_checksum more than once per packet
- Unify GRO and non-GRO csum verification as much as possible
- Unify the checksum functions (checksum_init)
- Simplify code
What is in this fifth patch set:
- Added GRO checksum validation functions
- Call the GRO validations functions from TCP and GRE gro_receive
- Perform checksum verification in the UDP gro_receive path using
GRO functions and add support for gro_receive in UDP6
Changes in V2:
- Change ip_summed to CHECKSUM_UNNECESSARY instead of moving it
to CHECKSUM_COMPLETE from GRO checksum validation. This avoids
performance penalty in checksumming bytes which are before the header
GRO is at.
Please review carefully and test if possible, mucking with basic
checksum functions is always a little precarious :-)
----
Test results with this patch set are below. I did not notice any
performace regression.
Tests run:
TCP_STREAM: super_netperf with 200 streams
TCP_RR: super_netperf with 200 streams and -r 1,1
Device bnx2x (10Gbps):
No GRE RSS hash (RX interrupts occur on one core)
UDP RSS port hashing enabled.
* GRE with checksum with IPv4 encapsulated packets
With fix:
TCP_STREAM
9.91% CPU utilization
5163.78 Mbps
TCP_RR
50.64% CPU utilization
219/347/502 90/95/99% latencies
834103 tps
Without fix:
TCP_STREAM
10.05% CPU utilization
5186.22 tps
TCP_RR
49.70% CPU utilization
227/338/486 90/95/99% latencies
813450 tps
* GRE without checksum with IPv4 encapsulated packets
With fix:
TCP_STREAM
10.18% CPU utilization
5159 Mbps
TCP_RR
51.86% CPU utilization
214/325/471 90/95/99% latencies
865943 tps
Without fix:
TCP_STREAM
10.26% CPU utilization
5307.87 Mbps
TCP_RR
50.59% CPU utilization
224/325/476 90/95/99% latencies
846429 tps
*** Simulate device returns CHECKSUM_COMPLETE
* VXLAN with checksum
With fix:
TCP_STREAM
13.03% CPU utilization
9093.9 Mbps
TCP_RR
95.96% CPU utilization
161/259/474 90/95/99% latencies
1.14806e+06 tps
Without fix:
TCP_STREAM
13.59% CPU utilization
9093.97 Mbps
TCP_RR
93.95% CPU utilization
160/259/484 90/95/99% latencies
1.10262e+06 tps
* VXLAN without checksum
With fix:
TCP_STREAM
13.28% CPU utilization
9093.87 Mbps
TCP_RR
95.04% CPU utilization
155/246/439 90/95/99% latencies
1.15e+06 tps
Without fix:
TCP_STREAM
13.37% CPU utilization
9178.45 Mbps
TCP_RR
93.74% CPU utilization
161/257/469 90/95/99% latencies
1.1068e+06 Mbps
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
In GRE demux if the GRE checksum pop rcv encapsulation so that any
encapsulated checksums are treated as tunnel checksums.
Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Implement GRO for UDPv6. Add UDP checksum verification in gro_receive
for both UDP4 and UDP6 calling skb_gro_checksum_validate_zero_check.
Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In tcp[64]_gro_receive call skb_gro_checksum_validate to validate TCP
checksum in the gro context.
Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add inet_gro_compute_pseudo and ip6_gro_compute_pseudo. These are
the logical equivalents of inet_compute_pseudo and ip6_compute_pseudo
for GRO path. The IP header is taken from skb_gro_network_header.
Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add skb_gro_checksum_validate, skb_gro_checksum_validate_zero_check,
and skb_gro_checksum_simple_validate, and __skb_gro_checksum_complete.
These are the cognates of the normal checksum functions but are used
in the gro_receive path and operate on GRO related fields in sk_buffs.
Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Replace open codings of (((u64) <x> * <y>) >> 32) with reciprocal_scale().
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Drivers, and perhaps other entities we have not yet considered,
sometimes want to know how deep the protocol headers go before
deciding how large of an SKB to allocate and how much of the packet to
place into the linear SKB area.
For example, consider a driver which has a device which DMAs into
pools of pages and then tells the driver where the data went in the
DMA descriptor(s). The driver can then build an SKB and reference
most of the data via SKB fragments (which are page/offset/length
triplets).
However at least some of the front of the packet should be placed into
the linear SKB area, which comes before the fragments, so that packet
processing can get at the headers efficiently. The first thing each
protocol layer is going to do is a "pskb_may_pull()" so we might as
well aggregate as much of this as possible while we're building the
SKB in the driver.
Part of supporting this is that we don't have an SKB yet, so we want
to be able to let the flow dissector operate on a raw buffer in order
to compute the offset of the end of the headers.
So now we have a __skb_flow_dissect() which takes an explicit data
pointer and length.
Signed-off-by: David S. Miller <davem@davemloft.net>
Florian Fainelli says:
====================
net: phy: bcm7xxx: APD and EEE support
This patch series enables Auto-power down and EEE for the BCM7xxx integrated
Gigabit PHYs.
I also put a fix for the fixed PHY that would allow clause 45 over clause 22
reads/writes but would return bogus data by using e.g: ethtool --show-eee
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
The 28nm Gigabit PHY on BCM7xxx chips comes out of reset with absolutely
no EEE capabilities, such that we would actually return that we do not
support EEE when accessing 3.20 (MDIO_PCS_EEE_ABLE) registers.
Poke through the vendor-specific C45 register to enable EEE globally at
the PHY level, and advertise supported EEE modes.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Internal PHYs do not have any specific phy_interface_t defined because
they are within an Ethernet MAC or a larger IC, they will fail the early
check in phy_init_eee(). Allow these PHYs to proceed with EEE
initialization and report error/success by checking the standard C45
EEE-related registers.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Some PHY drivers might need to access Clause 45 registers in Clause 22
compatibility mode to e.g: properly advertise EEE support when disabled
by default.
Export these two helper functions: phy_read_mmd_indirect() and
phy_write_mmd_indirect() for drivers to use them.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The fixed PHY driver does not properly emulate Clause 45 over Clause 22
MDIO reads, and as such, will return bogus values when we access such
registers.
Return an error when accessing these registers in order to prevent
advertising bogus capabilities such as EEE support and such.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>