7 Commits

Author SHA1 Message Date
Tobias Regnery
dc39a78b3c alx: add msi-x support
Add msi-x support to the alx driver. This is in preparation for multi queue
support.

msi-x interrupts are disabled by default because without multi queue support
there is no advantage over msi interrupts. The performance numbers observed
with iperf stay the same.

Based on information of the downstream driver at github.com/qca/alx

Signed-off-by: Tobias Regnery <tobias.regnery@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-09 20:51:21 -07:00
Tobias Regnery
9ee7b683ea alx: refactor msi enablement and disablement
Introduce a new flag field for the advanced interrupt capatibilities and add
new functions to enable and disable msi interrupts. These functions will be
extended later to cover msi-x interrupts.

We enable msi interrupts earlier in alx_init_intr because with msi-x and multi
queue support the number of queues must be set before we allocate resources for
the rx and tx paths.

Signed-off-by: Tobias Regnery <tobias.regnery@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-09 20:51:21 -07:00
Feng Tang
881d0327db net: alx: Work around the DMA RX overflow issue
Commit 26c5f03 uses a new skb allocator to avoid the RFD overflow
issue.

But from debugging without datasheet, we found the error always
happen when the DMA RX address is set to 0x....fc0, which is very
likely to be a HW/silicon problem.

So one idea is instead of adding a new allocator, why not just
hitting the right target by avaiding the error-prone DMA address?

This patch will actually
* Remove the commit 26c5f03
* Apply rx skb with 64 bytes longer space, and if the allocated skb
  has a 0x...fc0 address, it will use skb_resever(skb, 64) to
  advance the address, so that the RX overflow can be avoided.

In theory this method should also apply to atl1c driver, which
I can't find anyone who can help to test on real devices.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=70761
Signed-off-by: Feng Tang <feng.tang@intel.com>
Suggested-by: Eric Dumazet <edumazet@google.com>
Tested-by: Ole Lukoie <olelukoie@mail.ru>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-14 15:30:50 -04:00
Feng Tang
26c5f03b2a net: alx: use custom skb allocator
This patch follows Eric Dumazet's commit 7b70176421 for Atheros
atl1c driver to fix one exactly same bug in alx driver, that the
network link will be lost in 1-5 minutes after the device is up.

My laptop Lenovo Y580 with Atheros AR8161 ethernet device hit the
same problem with kernel 4.4, and it will be cured by Jarod Wilson's
commit c406700c for alx driver which get merged in 4.5. But there
are still some alx devices can't function well even with Jarod's
patch, while this patch could make them work fine. More details on
	https://bugzilla.kernel.org/show_bug.cgi?id=70761

The debug shows the issue is very likely to be related with the RX
DMA address, specifically 0x...f80, if RX buffer get 0x...f80 several
times, their will be RX overflow error and device will stop working.

For kernel 4.5.0 with Jarod's patch which works fine with my
AR8161/Lennov Y580, if I made some change to the
	__netdev_alloc_skb
		--> __alloc_page_frag()
to make the allocated buffer can get an address with 0x...f80,
then the same error happens. If I make it to 0x...f40 or 0x....fc0,
everything will be still fine. So I tend to believe that the
0x..f80 address cause the silicon to behave abnormally.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=70761
Cc: Eric Dumazet <edumazet@google.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Feng Tang <feng.tang@intel.com>
Tested-by: Ole Lukoie <olelukoie@mail.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-25 19:52:27 -04:00
Sabrina Dubroca
f1b6b1062a alx: add alx_get_stats64 operation
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Reviewed-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-11 20:52:58 -08:00
Johannes Berg
4a134c39db alx: make sizes unsigned
The ring sizes should be unsigned, pointed out by Ben Hutchings.

Reported-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-01 13:18:19 -07:00
Johannes Berg
ab69bde6b2 alx: add a simple AR816x/AR817x device driver
This is a very simple driver, based on the original vendor
driver that Qualcomm/Atheros published/submitted previously,
but reworked to make the code saner. However, it also lost
a number of features (TSO/GSO, VLAN acceleration and multi-
queue support) in the process, as well as debugging support
features I didn't have any use for. The only thing I left
is checksum offload.

More features can obviously be added, but this seemed like
a good start for having a driver in mainline at all.

Johannes Stezenbach has verified that the driver works on
AR8161, I have a AR8171 myself. The E2200 device ID I found
on github in somebody's repository.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-17 16:04:34 -07:00