For the "fsl,etsec2" compatible models the driver currently
supports 8 Tx and Rx DMA rings (aka HW queues).  However, there
are only 2 pairs of Rx/Tx interrupt lines, as these controllers
are integrated in low power SoCs with 2 CPUs at most.  As a result,
there are at most 2 NAPI instances that have to service multiple
Tx and Rx queues for these devices.  This complicates the NAPI
polling routine having to iterate over the mutiple Rx/Tx queues
hooked to the same interrupt lines.  And there's also an overhead
at HW level, as the controller needs to service all the 8 Tx rings
in a round robin manner.  The combined overhead shows up for multi
parallel Tx flows transmitted by the kernel stack, when the driver
usually starts returning NETDEV_TX_BUSY leading to NETDEV WATCHDOG
Tx timeout triggering if the Tx path is congested for too long.

As an alternative, this patch makes the driver support only one
Tx/Rx DMA ring per NAPI instance (per interrupt group or pair
of Tx/Rx interrupt lines) by default.  The simplified single queue
polling routine (gfar_poll_sq) will be the default napi poll routine
for the etsec2 devices too.  Some adjustments needed to be made to
link the Tx/Rx HW queues with each NAPI instance (2 in this case).
The gfar_poll_sq() is already successfully used by older SQ_SG_MODE
(single interrupt group) controllers.
This patch fixes Tx timeout triggering under heavy Tx traffic load
(i.e. iperf -c -P 8) for the "fsl,etsec2" (currently the only
MQ_MG_MODE devices).  There's also a significant memory footprint
reduction by supporting 2 Rx/Tx DMA rings (at most), instead of 8,
for these devices.
Signed-off-by: NClaudiu Manoil <claudiu.manoil@freescale.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There are some concurrency issues on devices w/ 2 CPUs related
to the handling of Rx and Tx interrupts.  eTSEC has separate
interrupt lines for Rx and Tx but a single imask register
to mask these interrupts and a single NAPI instance to handle
both Rx and Tx work.  As a result, the Rx and Tx ISRs are
identical, both are invoking gfar_schedule_cleanup(), however
both handlers can be entered at the same time when the Rx and
Tx interrupts are taken by different CPUs.  In this case
spurrious interrupts (SPU) show up (in /proc/interrupts)
indicating a concurrency issue.  Also, Tx overruns followed
by Tx timeout have been observed under heavy Tx traffic load.

To address these issues, the schedule cleanup ISR part has
been changed to handle the Rx and Tx interrupts independently.
The patch adds a separate NAPI poll routine for Tx cleanup to
be triggerred independently by the Tx confirmation interrupts
only.  Existing poll functions are modified to handle only
the Rx path processing.  The Tx poll routine does not need a
budget, since Tx processing doesn't consume NAPI budget, and
hence it is registered with minimum NAPI weight.
NAPI scheduling does not require locking since there are
different NAPI instances between the Rx and Tx confirmation
paths now.
So, the patch fixes the occurence of spurrious Rx/Tx interrupts.
Tx overruns also occur less frequently now.
Signed-off-by: NClaudiu Manoil <claudiu.manoil@freescale.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix warning about code defined but never used if IGB_HWMON not defined.
Reported-by: NStephen Hemminger <stephen@networkplumber.org>
Signed-off-by: NStephen Hemminger <stephen@networkplumber.org>
Tested-by: NAaron Brown <aaron.f.brown@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Use ARRAY_SIZE for array size calculation.
Signed-off-by: NTodd Fujinaka <todd.fujinaka@intel.com>
Tested-by: NAaron Brown <aaron.f.brown@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

skb->pkt_type is not a bitmask, but contains only value at a time from
the range defined in include/uapi/linux/if_packet.h.

Checking it like if it was a bitmask of values would also cause
PACKET_OTHERHOST, PACKET_LOOPBACK and PACKET_FASTROUTE to be matched by
this check since their lower 2 bits are also set, although that does not
fix a real bug, it is still potentially confusing.

This bogus check was introduced in commit 815cccbf ("ixgbe: add setlink,
getlink support to ixgbe and ixgbevf").
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Tested-by: NPhil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Previous commit c3a0dce3 fixed an overrun for the RAR on i218 devices.
This commit also attempted to homogenize the RAR/SHRA access for all parts
accessed by the e1000e driver.  This change introduced an error for
assigning MAC addresses to guest OS's for 82579 devices.

Only RAR[0] is accessible to the driver for 82579 parts, and additional
addresses must be placed into the SHRA[L|H] registers.  The rar_entry_count
was changed in the previous commit to an inaccurate value that accounted
for all RAR and SHRA registers, not just the ones usable by the driver.

This patch fixes the count to the correct value and adjusts the
e1000_rar_set_pch2lan() function to user the correct index.

Cc: John Greene <jogreene@redhat.com>
Signed-off-by: NDave Ertman <davidx.m.ertman@intel.com>
Tested-by: NAaron Brown <aaron.f.brown@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Changes to the rar_entry_count value require a change to the indexing
used to access the SHRA[H|L] registers when testing them with
'ethtool -t <iface> offline'
Signed-off-by: NDave Ertman <davidx.m.ertman@intel.com>
Tested-by: NAaron Brown <aaron.f.brown@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Valid values for InterruptThrottleRate are 10-100000, or one of
0, 1, 3, 4.  '2' is not valid.  This is a legacy from the branching
from the e1000 driver code that e1000e was based from.

Prior to this patch, if the e1000e driver  was loaded with a forced
invalid InterruptThrottleRate of '2', then no throttle rate would be
set and no error message generated.

Now, a message will be generated that an invalid value was used and the
value for InterruptThrottleRate will be set to the default value.
Signed-off-by: NDave Ertman <davidx.m.ertman@intel.com>
Tested-by: NJeff Pieper <jeffrey.e.pieper@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

ULP is a power saving feature that reduces the power consumption of the
PHY when a cable is not connected.

ULP is gated on the following conditions:
1) The hardware must support ULP.  Currently this is only I218
   devices from Intel
2) ULP is initiated by the driver, so, no driver results in no ULP.
3) ULP's implementation utilizes Runtime Power Management to toggle its
   execution.  ULP is enabled/disabled based on the state of Runtime PM.
4) ULP is not active when wake-on-unicast, multicast or broadcast is active
   as these features are mutually-exclusive.

Since the PHY is in an unavailable state while ULP is active, any access
of the PHY registers will fail.  This is resolved by utilizing kernel
calls that cause the device to exit Runtime PM (e.g. pm_runtime_get_sync)
and then, after PHY access is complete,  allow the device to resume
Runtime PM (e.g. pm_runtime_put_sync).

Under certain conditions, toggling the LANPHYPC is necessary to disable
ULP mode.  Break out existing code to toggle LANPHYPC to a new function
to avoid code duplication.
Signed-off-by: NDave Ertman <davidx.m.ertman@intel.com>
Cc: Bruce Allan <bruce.w.allan@intel.com>
Tested-by: NJeff Pieper <jeffrey.e.pieper@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Fix issues with:
RuntimePM causing the device to repeatedly flip between suspend and resume
with the interface administratively downed.
Having RuntimePM enabled interfering with the functionality of Energy
Efficient Ethernet.

Added checks to disallow functions that should not be executed if the
device is currently runtime suspended

Make runtime_idle callback to use same deterministic behavior as the igb
driver.
Signed-off-by: NDave Ertman <davidx.m.ertman@intel.com>
Acked-by: NBruce Allan <bruce.w.allan@intel.com>
Tested-by: NJeff Pieper <jeffrey.e.pieper@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Refactor the system power management flows to prevent the suspend path from
being executed twice when hibernating since both the freeze and
poweroff callbacks were set to e1000_suspend() via SET_SYSTEM_SLEEP_PM_OPS.
There are HW workarounds that are performed during this flow and calling
them twice was causing erroneous behavior.

Re-arrange the code to take advantage of common code paths and explicitly
set the individual dev_pm_ops callbacks for suspend, resume, freeze,
thaw, poweroff and restore.

Add a boolean parameter (reset) to the e1000e_down function to allow
for cases when the HW should not be reset when downed during a PM event.

Now that all suspend/shutdown paths result in a call to __e1000_shutdown()
that checks Wake on Lan status, removing redundant check for WoL in
e1000_power_down_phy().
Signed-off-by: NDave Ertman <davidx.m.ertman@intel.com>
Acked-by: NBruce Allan <bruce.w.allan@intel.com>
Tested-by: NJeff Pieper <jeffrey.e.pieper@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Branding strings from recently released and soon to be released
hardware configurations that are supported by e1000e.
Signed-off-by: NDave Ertman <davidx.m.ertman@intel.com>
Acked-by: NBruce Allan <bruce.w.allan@intel.com>
Tested-by: NJeff Pieper <jeffrey.e.pieper@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

This patch is to update the GPL header by removing the portion that
refers to the Free Software Foundation address.

Change the copyright date for 2014.

Reformat the header comments to conform to kernel networking coding norms
Signed-off-by: NDave Ertman <davidx.m.ertman@intel.com>
Tested-by: NJeff Pieper <jeffrey.e.pieper@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Enabling EEE LPI sooner than one second after link up on 82579 causes link
issues with some switches.

Remove EEE enablement for 82579 parts from the link initialization flow to
avoid initializing too early.  EEE initialization for 82579 will be done
in e1000e_update_phy_task.
Signed-off-by: NDave Ertman <davidx.m.ertman@intel.com>
Acked-by: NBruce W Allan <bruce.w.allan@intel.com>
Tested-by: NJeff Pieper <jeffrey.e.pieper@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

On a ME enabled system with the cable out, the driver init flow would
generate an erroneous message indicating that resets were being blocked
by an active ME session.  Cause was ME clearing the semaphore bit to
block further PHY resets for up to 50 msec during power-on/cycle.  After
this interval, ME would re-set the bit and allow PHY resets.

To resolve this, change the flow of e1000e_phy_hw_reset_generic() to
utilize a delay and retry method.  Poll the FWSM register to minimize
any extra time added to the flow.  If the delay times out at 100ms
(checked in 10msec increments), then return the value E1000_BLK_PHY_RESET,
as this is the accurate state of the PHY.  Attempting to alter just the
call to e1000e_phy_hw_reset_generic() in e1000_init_phy_workarounds_pchlan()
just caused the problem to move further down the flow.
Signed-off-by: NDave Ertman <davidx.m.ertman@intel.com>
Acked-by: NBruce W. Allan <bruce.w.allan@intel.com>
Tested-by: NJeff Pieper <jeffrey.e.pieper@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Cleaning up some pointer references that are no longer necessary
Signed-off-by: NDave Ertman <davidx.m.ertman@intel.com>
Tested-by: NJeff Pieper <jeffrey.e.pieper@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Add lock in e1000e_phc_adjfreq to prevent concurrent changes to TIMINCA
and SYSTIMH/L.
Signed-off-by: NTodd Fujinaka <todd.fujinaka@intel.com>
Tested-by: NJeff Pieper <jeffrey.e.pieper@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Support hw IPv6 checksum for TCP and UDP packets.

Note that the hw has the limitation of the range of the transport
offset. Besides, the TCP Pseudo Header of the IPv6 TSO of the hw
bases on the Microsoft document which excludes the packet length.
Signed-off-by: NHayes Wang <hayeswang@realtek.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Support scatter gather and TSO.

Adjust the tx checksum function and set the max gso size to fix the
size of the tx aggregation buffer.
Signed-off-by: NHayes Wang <hayeswang@realtek.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Support hw rx checksum for TCP and UDP packets.
Signed-off-by: NHayes Wang <hayeswang@realtek.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Continue dealing with the remain rx packets, even though the allocation
of the skb fail. This could calculate the correct dropped packets.
Signed-off-by: NHayes Wang <hayeswang@realtek.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

move the tx_bottom() from delayed_work to tasklet. It makes the rx
and tx balanced. If the device is in runtime suspend when getting
the tx packet, wakeup the device before trasmitting.
Signed-off-by: NHayes Wang <hayeswang@realtek.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Check tx agg list before spin lock to avoid doing spin lock every
times.
Signed-off-by: NHayes Wang <hayeswang@realtek.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use spin_lock and spin_unlock in interrupt context.

The ndo_start_xmit would not be called in interrupt context, so
replace the relative spin_lock_irqsave and spin_unlock_irqrestore
with spin_lock_bh and spin_unlock_bh.
Signed-off-by: NHayes Wang <hayeswang@realtek.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Unmapping causes TLB flushing, therefore we should make it in the largest
possible batches. However we shouldn't starve the guest for too long. So if
the guest has space for at least two big packets and we don't have at least a
quarter ring to unmap, delay it for at most 1 milisec.
Signed-off-by: NZoltan Kiss <zoltan.kiss@citrix.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

A malicious or buggy guest can leave its queue filled indefinitely, in which
case qdisc start to queue packets for that VIF. If those packets came from an
another guest, it can block its slots and prevent shutdown. To avoid that, we
make sure the queue is drained in every 10 seconds.
The QDisc queue in worst case takes 3 round to flush usually.
Signed-off-by: NZoltan Kiss <zoltan.kiss@citrix.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Xen network protocol had implicit dependency on MAX_SKB_FRAGS. Netback has to
handle guests sending up to XEN_NETBK_LEGACY_SLOTS_MAX slots. To achieve that:
- create a new skb
- map the leftover slots to its frags (no linear buffer here!)
- chain it to the previous through skb_shinfo(skb)->frag_list
- map them
- copy and coalesce the frags into a brand new one and send it to the stack
- unmap the 2 old skb's pages

It's also introduces new stat counters, which help determine how often the guest
sends a packet with more than MAX_SKB_FRAGS frags.

NOTE: if bisect brought you here, you should apply the series up until
"xen-netback: Timeout packets in RX path", otherwise malicious guests can block
other guests by not releasing their sent packets.
Signed-off-by: NZoltan Kiss <zoltan.kiss@citrix.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

These counters help determine how often the buffers had to be copied. Also
they help find out if packets are leaked, as if "sent != success + fail",
there are probably packets never freed up properly.

NOTE: if bisect brought you here, you should apply the series up until
"xen-netback: Timeout packets in RX path", otherwise Windows guests can't work
properly and malicious guests can block other guests by not releasing their sent
packets.
Signed-off-by: NZoltan Kiss <zoltan.kiss@citrix.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

These became obsolete with grant mapping. I've left intentionally the
indentations in this way, to improve readability of previous patches.

NOTE: if bisect brought you here, you should apply the series up until
"xen-netback: Timeout packets in RX path", otherwise Windows guests can't work
properly and malicious guests can block other guests by not releasing their sent
packets.
Signed-off-by: NZoltan Kiss <zoltan.kiss@citrix.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch introduces grant mapping on netback TX path. It replaces grant copy
operations, ditching grant copy coalescing along the way. Another solution for
copy coalescing is introduced in "xen-netback: Handle guests with too many
frags", older guests and Windows can broke before that patch applies.
There is a callback (xenvif_zerocopy_callback) from core stack to release the
slots back to the guests when kfree_skb or skb_orphan_frags called. It feeds a
separate dealloc thread, as scheduling NAPI instance from there is inefficient,
therefore we can't do dealloc from the instance.
Signed-off-by: NZoltan Kiss <zoltan.kiss@citrix.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

RX path need to know if the SKB fragments are stored on pages from another
domain.
Logically this patch should be after introducing the grant mapping itself, as
it makes sense only after that. But to keep bisectability, I moved it here. It
shouldn't change any functionality here. xenvif_zerocopy_callback and
ubuf_to_vif are just stubs here, they will be introduced properly later on.
Signed-off-by: NZoltan Kiss <zoltan.kiss@citrix.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch contains a few bits of refactoring before introducing the grant
mapping changes:
- introducing xenvif_tx_pending_slots_available(), as this is used several
  times, and will be used more often
- rename the thread to vifX.Y-guest-rx, to signify it does RX work from the
  guest point of view
Signed-off-by: NZoltan Kiss <zoltan.kiss@citrix.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Storing the pending_idx at the first byte of the linear buffer never looked
good, skb->cb is a more proper place for this. It also prevents the header to
be directly grant copied there, and we don't have the pending_idx after we
copied the header here, so it's time to change it.
It also introduces helpers for the RX side
Signed-off-by: NZoltan Kiss <zoltan.kiss@citrix.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Additionally to have the second (data) bitrate available the data bitrate
has to be greater or equal to the arbitration bitrate in CAN FD.
Signed-off-by: NOliver Hartkopp <socketcan@hartkopp.net>
Acked-by: NStephane Grosjean <s.grosjean@peak-system.com>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

The configuration for CAN FD depends on CAN_CTRLMODE_FD enabled in the driver
specific ctrlmode_supported capabilities.

The configuration can be done either with the 'fd { on | off }' option in the
'ip' tool from iproute2 or by setting the CAN netdevice MTU to CAN_MTU (16) or
to CANFD_MTU (72).
Signed-off-by: NOliver Hartkopp <socketcan@hartkopp.net>
Acked-by: NStephane Grosjean <s.grosjean@peak-system.com>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

As CAN FD offers a second bitrate for the data section of the CAN frame the
infrastructure for storing and configuring this second bitrate is introduced.
Improved the readability of the if-statement by inserting some newlines.
Signed-off-by: NOliver Hartkopp <socketcan@hartkopp.net>
Acked-by: NStephane Grosjean <s.grosjean@peak-system.com>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

As the bittiming calculation functions are to be used with different
bittiming_const structures for CAN and CAN FD the direct reference to
priv->bittiming_const inside these functions has to be removed.

Also moved the check for existing bittiming const to one place.
Signed-off-by: NOliver Hartkopp <socketcan@hartkopp.net>
Acked-by: NStephane Grosjean <s.grosjean@peak-system.com>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

This patch moves a sanity check in order to have a second user for CAN FD.
Also simplify the return value generation in can_get_bittiming() as only
correct return values of can_[calc|fixup]_bittiming() lead to a return value of
zero.
Signed-off-by: NOliver Hartkopp <socketcan@hartkopp.net>
Acked-by: NStephane Grosjean <s.grosjean@peak-system.com>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

When setting the bitrate both can_calc_bittiming() and can_fixup_bittiming()
lead to the bitrate variable to be set, when a proper bit timing is available.
Only then the bitrate configuration is stored for the device, so checking for
priv->bittiming.bitrate is always sufficient.
Signed-off-by: NOliver Hartkopp <socketcan@hartkopp.net>
Acked-by: NStephane Grosjean <s.grosjean@peak-system.com>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

The skbuff protocol value was formerly fixed/sanitized to ETH_P_CAN in
can_put_echo_skb(). With CAN FD this value has to be preserved.
This patch changes the hard assignment of the protocol value to a check of
valid protocol values for CAN and CAN FD.
Signed-off-by: NOliver Hartkopp <socketcan@hartkopp.net>
Acked-by: NStephane Grosjean <s.grosjean@peak-system.com>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>