Stop using the old legacy PM support, since we now have stable support
for the newer generic PM callbacks.

This has several advantages. First, we no longer have to manage our
own pci_save_state() and power changes, as it's preferred to have the
PCI stack do this. Second, these routines get called for both hibernate
and suspend to ram, so we can have the driver properly handle all the
suspend/resume flows that it needs to.
Signed-off-by: NJacob Keller <jacob.e.keller@intel.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

We currently (mis)use the __I40E_RECOVERY_PENDING bit to determine when
we should actually request a new IRQ in i40e_setup_misc_vector().

This led to a design mistake where we open-coded the re-setup of the
miscellaneous vector in i40e_resume() instead of using the function
provided. If we did not open-code this and instead tried to use the
i40e_setup_misc_vector() function, it would lead to never reallocating
the IRQ.

This would lead to a second i40e_suspend() call failing to free the
vector due to a NULL pointer dereference.

A future patch is going to re-work how the i40e_suspend() and
i40e_resume() flows work to clear all IRQ vectors, which would require
us to use i40e_setup_misc_vector() directly. Since during this time the
__I40E_RECOVERY_PENDING bit is set, we'll never re-allocate the vector.

Rather than leaving the open-coded setup in i40e_resume() lets just fix
the problem properly in i40e_setup_misc_vector().

Introduce a new state bit which indicates when the IRQ has been
assigned, which will be set when i40e_setup_misc_vector is first called.
This ultimately resolves the issue of re-requesting the vector, without
overloading the __I40E_RECOVERY_PENDING state. This ensures that the
suspend/resume cycle can use the setup function instead of open-coding
the re-request during resume.

Additionally, since the only callers of i40e_stop_misc_vector also want
to free it, move this code directly into the function to avoid
duplication. Due to the new functionality, rename it to
i40e_free_misc_vector().

This lets us drop the extra calls to free and re-enable the vector
during i40e_suspend() and i40e_resume(). We don't need to call
i40e_setup_misc_Vector() in i40e_resume() because it gets called by the
i40e_rebuild() call.
Signed-off-by: NJacob Keller <jacob.e.keller@intel.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

An errata with GLQF_PCNT causes it to not wrap as expected. This
can cause an error in flow director statistics. This patch resets
affected counters just after reading.
Signed-off-by: NMariusz Stachura <mariusz.stachura@intel.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Fortville and Fort Park devices are often on different firmware release
schedules. This change relaxes the minor version warning message,
so it is only displayed for older FW warning version for old
firmware Fortville 3 or earlier.
Signed-off-by: NMariusz Stachura <mariusz.stachura@intel.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

This commit replaces usage of vsi->back in i40e_print_link_message()
(which is actually a PF pointer) with temp variable.
Signed-off-by: NSudheer Mogilappagari <sudheer.mogilappagari@intel.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

i40e_print_link_message() is intended to compare new
link state with current link state and print log message
only if the new state is different from current state.

However in current driver the new state does not get updated
when link is going down because of the if condition. When an
interface is brought down, vsi->state is set to I40E_VSI_DOWN
in i40e_vsi_close() and later i40e_print_link_message() does
not get invoked in i40e_link_event due to if condition. Hence
link down message doesn't appear when link is going down. The
down state is seen  later during i40e_open() and old state
gets printed. The actual link state doesn't get updated in
i40e_close() or i40e_open() but when i40e_handle_link_event is
called inside i40e_clean_adminq_subtask.

This change allows i40e_print_link_message() to be called when
interface is going down and keeps the state information updated.
Signed-off-by: NSudheer Mogilappagari <sudheer.mogilappagari@intel.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

In current driver, when ifconfig ethx up is done, the link state
doesn't transition to UP inside i40e_open(). It changes after AQ
command response is handled in i40e_handle_link_event().

When pf->hw.phy.link_info.link_info is DOWN inside i40e_open(),
The state is transient and invalid. So log message gets printed
based on incorrect info (i.e link_info and an_info).

This commit removes check for unqualified module inside
i40e_up_complete(). The existing check in i40e_handle_link_event()
logs the error message based on correct link state information.
Signed-off-by: NSudheer Mogilappagari <sudheer.mogilappagari@intel.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

On older kernels a call to irq_set_affinity_hint does not guarantee that
the IRQ affinity will be set. If nothing else on the system sets the IRQ
affinity this can result in a bug in the i40e_napi_poll() routine where
we notice that our interrupt fired on the "wrong" CPU according to our
internal affinity_mask variable.

This results in a bug where we continuously tell NAPI to stop polling to
move the interrupt to a new CPU, but the CPU never changes because our
affinity mask does not match the actual mask setup for the IRQ.

The root problem is a mismatched affinity mask value. So lets initialize
the value to cpu_possible_mask instead. This ensures that prior to the
first time we get an IRQ affinity notification we'll have the mask set
to include every possible CPU.

We use cpu_possible_mask instead of cpu_online_mask since the former is
almost certainly never going to change, while the later might change
after we've made a copy.
Signed-off-by: NJacob Keller <jacob.e.keller@intel.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Since commit 3ffa037d ("i40e: Set XPS bit mask to zero in DCB mode")
we've tried to reset the XPS settings by building a custom
empty CPU mask.

This workaround is not necessary because we're not really removing the
XPS setting, but simply setting it so that no CPU is valid.

Second, we shorten the code further by using zalloc_cpumask_var instead
of a separate call to bitmap_zero().
Signed-off-by: NJacob Keller <jacob.e.keller@intel.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

This patch fixes an issue where an error return value is
set, but without an immediate exit, the value can be overwritten
by the following code execution.  The condition  at this point
is not fatal, so remove the error assignment and comment the
intent for future code maintainers
Signed-off-by: NCarolyn Wyborny <carolyn.wyborny@intel.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

This patch improves the system log message. The log message will
be expanded to include the FEC mode the FW requested before link
was established.
Signed-off-by: NMariusz Stachura <mariusz.stachura@intel.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

In new versions of GCC since 7.x a new warning exists which warns when
a string is truncated before all of the format can be completed.

When we setup VMDQ netdev names we are copying a pre-existing interface
name which could be up to 15 characters in length. Since we also add
4 bytes, v, the literal %, the d and a \0 null, we would overrun the
available size unless snprintf truncated for us.

The snprintf call will of course truncate on the end, so lets instead
modify the code to force truncation of the copied netdev name by
4 characters, to create enough space for the 4 bytes we're adding.
Signed-off-by: NJacob Keller <jacob.e.keller@intel.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

According to the header file cpumask.h, we shouldn't be directly copying
a cpumask_t, since its a bitmap and might not be copied correctly. Lets
use the provided cpumask_copy() function instead.
Signed-off-by: NJacob Keller <jacob.e.keller@intel.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

In i40e_vsi_add_vlan we treat attempting to add VID=0 as an error,
because it does not do what the caller might expect. We already special
case VID=0 in i40e_vlan_rx_add_vid so that we avoid this error when
adding the VLAN.

This special casing is necessary so that we do not add the VLAN=0 filter
since we don't want to stop receiving untagged traffic. Unfortunately,
not all callers of i40e_vsi_add_vlan are aware of this, including when
we add VLANs from a VF device.

Rather than special casing every single caller of i40e_vsi_add_vlan,
lets just move this check internally. This makes the code simpler
because the caller does not need to be aware of how VLAN=0 is special,
and we don't forget to add this check in new places.

This fixes a harmless error message displaying when adding a VLAN from
within a VF. The message was meaningless but there is no reason to
confuse end users and system administrators, and this is now avoided.
Signed-off-by: NJacob Keller <jacob.e.keller@intel.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

This patch fixes a problem with the HW ATR eviction feature where the
NVM setting was incorrect.  This patch detects the issue on X720
adapters and disables the feature if the NVM setting is incorrect.

Without this patch, HW ATR Evict feature does not work on broken NVMs
and is not detected either.  If the HW ATR Evict feature is disabled
the SW Eviction feature will take effect.
Signed-off-by: NAnjali Singhai Jain <anjali.singhai@intel.com>
Signed-off-by: NAlice Michael <alice.michael@intel.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Since commit b499ffb0 ("i40e: Look up MAC address in Open Firmware
or IDPROM"), we've had support for obtaining the MAC address
form Open Firmware or IDPROM.

This code relied on sending the Open Firmware address directly to the
device firmware instead of relying on our MAC/VLAN filter list. Thus,
a work around was introduced in commit b1b15df5 ("i40e: Explicitly
write platform-specific mac address after PF reset")

We refactored the Open Firmware address enablement code in the ill-named
commit 41c4c2b5 ("i40e: allow look-up of MAC address from Open
Firmware or IDPROM")

Since this refactor, we no longer even set I40E_FLAG_PF_MAC. Further, we
don't need this work around, because we actually store the MAC address
as part of the MAC/VLAN filter hash. Thus, we will restore the address
correctly upon reset.

The refactor above failed to revert the workaround, so do that now.
Signed-off-by: NJacob Keller <jacob.e.keller@intel.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

The number of flags found in pf->flags has grown quite large, and there
are a lot of different types of flags. Most of the flags are simply
hardware features which are enabled on some firmware or some MAC types.
Other flags are dynamic run-time flags which enable or disable certain
features of the driver.

Separate these two types of flags into pf->hw_features and pf->flags.
The hw_features list will contain a set of features which are enabled at
init time. This will not contain toggles or otherwise dynamically
changing features. These flags should not need atomic protections, as
they will be set once during init and then be essentially read only.

Everything else will remain in the flags variable. These flags may be
modified at any time during run time. A future patch may wish to convert
these flags into set_bit/clear_bit/test_bit or similar approach to
ensure atomic correctness.

The I40E_FLAG_MFP_ENABLED flag may be a good fit for hw_features but
currently is used by ethtool in the private flags settings, and thus has
been left as part of flags.

Additionally, I40E_FLAG_DCB_CAPABLE may be a good fit for the
hw_features but this patch has not tried to untangle it yet.
Signed-off-by: NJacob Keller <jacob.e.keller@intel.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

The X722 pf flag setup should happen before the VMDq RSS queue count is
initialized for VMDq VSI to get the right number of queues for RSS in
case of X722 devices.
Signed-off-by: NAnjali Singhai Jain <anjali.singhai@intel.com>
Signed-off-by: NAlice Michael <alice.michael@intel.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Now that the kernel supports double VLAN tags, we should at least play
nice. Adjust the max packet size to account for two VLAN tags, not just
one.
Signed-off-by: NMitch Williams <mitch.a.williams@intel.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Get rid of struct tc_to_netdev which is now just unnecessary container
and rather pass per-type structures down to drivers directly.
Along with that, consolidate the naming of per-type structure variables
in cls_*.
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Acked-by: NJamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Change the return value from -EINVAL to -EOPNOTSUPP. The rest of the
drivers have it like that, so be aligned.
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Acked-by: NJamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

As ndo_setup_tc is generic offload op for whole tc subsystem, does not
really make sense to have cls-specific args. So move them under
cls_common structurure which is embedded in all cls structs.
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Acked-by: NJamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since the type is always present, push it to be a separate argument to
ndo_setup_tc. On the way, name the type enum and use it for arg type.
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Acked-by: NJamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fill the XDP prog_id with the id just like we do in other XDP enabled
drivers such as ixgbe. This is needed so that on dump we can retrieve
the attached program based on the id, and dump BPF insns, opcodes, etc
back to user space. Only XDP driver missing this is currently i40e.
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NJohn Fastabend <john.fastabend@gmail.com>
Acked-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

The i40e driver attempts to display the UDP tunnel name by doing a check
against the type, where for non-zero types we use "vxlan" and for zero
type we use "geneve". This is not future proof, because if new tunnel
types get added, we'll incorrectly label them. It also depends on the
value of UDP_TUNNEL_TYPE_GENEVE == 0, which is brittle.

Instead, replace this with a function that can return a constant string
depending on the type. For now we'll use "unknown" for types we don't
know about, and we can expand this in the future if new types get added.
Signed-off-by: NJacob Keller <jacob.e.keller@intel.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Compiler reported several places where driver compared
signed and unsigned types.  Cast or change the types to remove
the warnings.
Signed-off-by: NJesse Brandeburg <jesse.brandeburg@intel.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

During certain events such as a CORER, multiple devices will run a work
task to handle some cleanup. This can cause issues due to
a single-threaded workqueue which can mean that a device doesn't cleanup
in time. Prevent this by removing the single-threaded restriction on the
module workqueue. This avoids the need to add more complex yielding
logic in our service task routine. This is also similar to what other
drivers such as fm10k do.
Signed-off-by: NJacob Keller <jacob.e.keller@intel.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

This patch fixes a problem found in systems when entering
S4 state.  This patch fixes the problem by ensuring that
the misc vector's IRQ is disabled as well.  Without this
patch a stack trace can be seen upon entering S4 state.
Signed-off-by: NCarolyn Wyborny <carolyn.wyborny@intel.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

We recently refactored i40e_do_reset() and its friends to be able to
hold the RTNL lock only for the portions that actually need to be
protected. However, a separate refactoring added several new callers of
these functions during the PCIe error recovery and suspend/resume
cycles.

When merging the changes together, it was not noticed that we could
reduce the RTNL scope by letting the reset function handle the lock
itself, as previously it was not possible.

Fix this by replacing these call sites to indicate that the reset
function should handle its own lock. This enables multiple PFs to reset
or resume simultaneously without serializing the resets via the RTNL
lock. The end result is that on systems with lots of PFs and VFs the
resets don't stall waiting for each other to finish.

It is probable that we can also do the same for i40e_do_reset_safe, but
this author did not research that change carefully enough to be
confident.
Signed-off-by: NJacob Keller <jacob.e.keller@intel.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

When IWARP is enabled, we weren't clearing the PE_CRITERR, just logging
it and removing it from the mask. We need to do a corer to reset the
PE_CRITERR register, so set the bit for that as we handle the
interrupt.

We should also be checking for the error against the PFINT_ICR0 register,
and only need to clear it in the value getting written to
PFINT_ICR0_ENA.
Signed-off-by: NCatherine Sullivan <catherine.sullivan@intel.com>
Signed-off-by: NMitch Williams <mitch.a.williams@intel.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

When disabling interrupts, we should only be clearing the CAUSE_ENA bit,
not clearing the whole register.  Clearing the whole register sets the
NEXTQ_IDX field to 0 instead of 0x7ff which can confuse the Firmware in
some reset sequences.
Signed-off-by: NShannon Nelson <shannon.nelson@intel.com>
Signed-off-by: NMitch Williams <mitch.a.williams@intel.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

There exists a bug in which the driver does not correctly exit overflow
promiscuous mode.  This can occur if "too many" mac filters are added,
putting the driver into overflow promiscuous mode, and the filters are
then removed.  When the failed filters are removed, the driver reports
exiting overflow promiscuous mode which is correct, however traffic
continues to be received as if in promiscuous mode still.

The bug occurs because the conditional for toggling promiscuous mode was
set to only execute when promiscuous mode was enabled and not when it
was disabled as well.  This patch fixes the conditional to correctly
execute when promiscuous mode is toggled and not just enabled.  Without
this patch, the driver is unable to correctly exit overflow promiscuous
mode.
Signed-off-by: NAlan Brady <alan.brady@intel.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

This patch adds support for OEM firmware version. If OEM specific
adapter is detected ethtool reports OEM product version in firmware
version string instead of etrack id.
Signed-off-by: NFilip Sadowski <filip.sadowski@intel.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Partition bandwidth control is not in just one form of MFP (multi-function
partitioning), so make the code more generic and be sure to nudge the Tx
scheduler for all MFP.

Copyright updated to 2017.
Signed-off-by: NShannon Nelson <shannon.nelson@intel.com>
Signed-off-by: NMitch Williams <mitch.a.williams@intel.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

This patch adds proper XDP_TX action support. For each Tx ring, an
additional XDP Tx ring is allocated and setup. This version does the
DMA mapping in the fast-path, which will penalize performance for
IOMMU enabled systems. Further, debugfs support is not wired up for
the XDP Tx rings.
Signed-off-by: NBjörn Töpel <bjorn.topel@intel.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

This commit adds basic XDP support for i40e derived NICs. All XDP
actions will end up in XDP_DROP.
Signed-off-by: NBjörn Töpel <bjorn.topel@intel.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

A recent commit to refactor the driver and remove the hw_disabled_flags
field accidentally introduced two regressions. First, we overwrote
pf->flags which removed various key flags including the MSI-X settings.

Additionally, it was intended that we have now two flags,
HW_ATR_EVICT_CAPABLE and HW_ATR_EVICT_ENABLED, but this was not done,
and we accidentally were mis-using HW_ATR_EVICT_CAPABLE everywhere.

This patch adds the missing piece, HW_ATR_EVICT_ENABLED, and safely
updates pf->flags instead of overwriting it.

Without this patch we will have many problems including disabling MSI-X
support, and we'll attempt to use HW ATR eviction on devices which do
not support it.

Fixes: 47994c11 ("i40e: remove hw_disabled_flags in favor of using separate flag bits", 2017-04-19)
Signed-off-by: NJacob Keller <jacob.e.keller@intel.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We need to push the chain index down to the drivers, so they have the
information to which chain the rule belongs. For now, no driver supports
multichain offload, so only chain 0 is supported. This is needed to
prevent chain squashes during offload for now. Later this will be used
to implement multichain offload.
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit 0da36b97 ("i40e: use DECLARE_BITMAP for state fields")
introduced changes in the way i40e works with state flags converting
them to bitmaps using kernel bitmap API. This change introduced a
regression due to a mistaken substitution using __I40E_VSI_DOWN instead
of __I40E_DOWN when testing state of a PF at i40e_reset_subtask()
function. This caused a flood in the kernel log with the follow message:

[49.013] i40e 0002:01:00.0: bad reset request 0x00000020

Commit d19cb64b ("i40e: separate PF and VSI state flags")
also introduced some misuse of the VSI and PF flags, so both could be
considered as the offenders.

This patch simply fixes the flags where it makes sense by changing
__I40E_VSI_DOWN to __I40E_DOWN.

Fixes: 0da36b97 ("i40e: use DECLARE_BITMAP for state fields")
Fixes: d19cb64b ("i40e: separate PF and VSI state flags")
Reviewed-by: N"Guilherme G. Piccoli" <gpiccoli@linux.vnet.ibm.com>
Signed-off-by: N"Mauro S. M. Rodrigues" <maurosr@linux.vnet.ibm.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

The i40e driver has logic to handle only one Tx timestamp at a time,
using a state bit lock to avoid multiple requests at once.

It may be possible, if incredibly unlikely, that a Tx timestamp event is
requested but never completes. Since we use an interrupt scheme to
determine when the Tx timestamp occurred we would never clear the state
bit in this case.

Add an i40e_ptp_tx_hang() function similar to the already existing
i40e_ptp_rx_hang() function. This function runs in the watchdog routine
and makes sure we eventually recover from this case instead of
permanently disabling Tx timestamps.

Note: there is no currently known way to cause this without hacking the
driver code to force it.
Signed-off-by: NJacob Keller <jacob.e.keller@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>