The TODO list for the hfi1 driver was completed during 4.6. In addition
other objections raised (which are far beyond what was in the TODO list)
have been addressed as well. It is now time to remove the driver from
staging and into the drivers/infiniband sub-tree.
Reviewed-by: NJubin John <jubin.john@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

The deletion of a cdev is not a fence for holding off references to the
structure. The driver attempts to delete the cdev and then proceeds to
free the parent structure, the hfi1_devdata, or dd. This can potentially
lead to a kernel panic in situations where a user has an FD for the cdev
open, and the pci device gets removed. If the user then closes the FD
there will be a NULL dereference when trying to do put on the cdev's
kobject.

Fix this by pointing the cdev's kobject.parent at a new kobject embedded
in its parent structure. Also take a reference when the device is opened
and put it back when it is closed.
Reviewed-by: NMitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: NIra Weiny <ira.weiny@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Remove "IB" keyword from log messages.
Correct comment for thermal sensor init function.
Reviewed-by: NDean Luick <dean.luick@intel.com>
Signed-off-by: NJakub Pawlak <jakub.pawlak@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

QSFP modules can raise an interrupt to inform us of expected conditions
while the link is down, such as RX power low. Actively ignore these
conditions when the link is down as they only add reporting noise.
Continue reporting conditions that are valid at all times, such as
temperature alarms and warnings.
Reviewed-by: NDean Luick <dean.luick@intel.com>
Signed-off-by: NEaswar Hariharan <easwar.hariharan@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Clock and data recovery mechanisms (CDRs) in active QSFP modules
can be turned on or off to improve the bit error rate observed on
the channel. Signal integrity and bit error rate requirements require
us to always turn on any CDRs present in low power cables (power
dissipation 2.5W or lower). However, we adhere to the platform
designer's settings (provided in the platform configuration) for
higher power cables (dissipation 3.5W or higher) if the platform
designer has determined that the platform requires the CDRs to be
turned on (or off) and is capable of supplying and cooling the higher
power modules.

This patch also introduces the get_qsfp_power_class function to
centralize the bit twiddling required to determine the QSFP power class
across the code. Reusing this function improves the readability of code
that depends on knowing the power class of the cable, such as the
active and optical channel tuning algorithm.
Reviewed-by: NDean Luick <dean.luick@intel.com>
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NEaswar Hariharan <easwar.hariharan@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Add the P_KEY check for user-context mechanism for
both PIO and SDMA. For PIO, the
SendCtxtCheckEnable.DisallowKDETHPackets is set by
default. When the P_KEY is set,
SendCtxtCheckEnable.DisallowKDETHPackets is cleared.
For SDMA, a software check was included. This change
requires user processes to set the P_KEY before sending
any packets, otherwise, the sent packet will fail. The
original submission didn't have this check but it's
required.
Reviewed-by: NDean Luick <dean.luick@intel.com>
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Reviewed-by: NMikto Haralanov <mitko.haralanov@intel.com>
Signed-off-by: NSebastian Sanchez <sebastian.sanchez@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Increasing the default MTU size to 10KB improves performance
for PSM. Change the default MTU to 10KB but constrain
Verbs MTU to 8KB. Also update default MTU module parameter
description to be HFI1_DEFAULT_MAX_MTU.
Reviewed-by: NDean Luick <dean.luick@intel.com>
Reviewed-by: NMitko Haralanov <mitko.haralanov@intel.com>
Reviewed-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Reviewed-by: NJubin John <jubin.john@intel.com>
Signed-off-by: NSebastian Sanchez <sebastian.sanchez@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

The function hdr2sc was using an unshifted mask to obtain
the 5th bit of the service class.  Correct the issue by using
the shifted mask.
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDean Luick <dean.luick@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Use the new function to query whether the expected receive
user buffer can be pinned successfully. This requires that
a new variable be added to the hfi1_filedata structure used
to hold the number of pages pinned by the expected receive
code.
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Reviewed-by: NDean Luick <dean.luick@intel.com>
Signed-off-by: NMitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: NJubin John <jubin.john@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

This change adds a pointer to the process mm_struct when
calling hfi1_release_user_pages().

Previously, the function used the mm_struct of the current
process to adjust the number of pinned pages. However, is some
cases, namely when unpinning pages due to a MMU notifier call,
we want to drop into that code block as it will cause a deadlock
(the MMU notifiers take the process' mmap_sem prior to calling
the callbacks).

By allowing to caller to specify the pointer to the mm_struct,
the caller has finer control over that part of hfi1_release_user_pages().
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Reviewed-by: NDean Luick <dean.luick@intel.com>
Signed-off-by: NMitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: NJubin John <jubin.john@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

System administrators can use the locked memory
ulimit setting to set the maximum amount of memory
a user can lock/pin. However, this setting alone is not
enough to guarantee good operation of the hfi1 driver
due to the fact that the setting does not have fine
enough granularity to account for the limit being used
by multiple user processes and caches.

Therefore, a better limiting algorithm is needed. This
is where the new hfi1_can_pin_pages() function and the
cache_size module parameter come in.

The function works by looking at the ulimit and cache_size
value to compute a cache size. The algorithm examines the
ulimit value and, if it is not "unlimited", computes a
per-cache limit based on the number of configured user
contexts.

After that, the lower of the two - cache_size and computed
per-cache limit - is used.
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Reviewed-by: NDean Luick <dean.luick@intel.com>
Signed-off-by: NMitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: NJubin John <jubin.john@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

The usage of function pointers for RB node insertion
and removal in the expected receive code path was
meant to be a small performance optimization. However,
maintaining it, especially with the new MMU API, would
become more troublesome as the API is extended.

Since the performance optimization is minor, remove the
function pointers and replace with direct calls.
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Reviewed-by: NDean Luick <dean.luick@intel.com>
Signed-off-by: NMitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: NJubin John <jubin.john@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

The MMU notification code added to the
expected receive side has been re-factored and
split into it's own file. This was done in
order to make the code more general and, therefore,
usable by other parts of the driver.

The caching behavior remains the same. However,
the handling of the RB tree (insertion, deletions,
and searching) as well as the MMU invalidation
processing is now handled by functions in the
mmu_rb.[ch] files.
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Reviewed-by: NDean Luick <dean.luick@intel.com>
Signed-off-by: NMitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: NJubin John <jubin.john@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

The current LED beaconing code is unclear and uses the timer handler to
turn off the timer. This patch simplifies the code by removing the
special semantics of timeon = timeoff = 0 being interpreted as a request
to turn off the beaconing.
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NEaswar Hariharan <easwar.hariharan@intel.com>
Signed-off-by: NJubin John <jubin.john@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

The flag HFI1_DO_INIT_ASIC flag is no longer used.  Remove
the flag and the code that sets it.
Reviewed-by: NMitko Haralanov <mitko.haralanov@intel.com>
Reviewed-by: NEaswar Hariharan <easwar.hariharan@intel.com>
Signed-off-by: NDean Luick <dean.luick@intel.com>
Signed-off-by: NJubin John <jubin.john@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Remove the mutex guarding each operation in favor the ASIC
resource acquire/release.  Push the resource acquire/release,
above each operation call to allow exclusive access across
multiple operations.
Reviewed-by: NMitko Haralanov <mitko.haralanov@intel.com>
Reviewed-by: NEaswar Hariharan <easwar.hariharan@intel.com>
Signed-off-by: NDean Luick <dean.luick@intel.com>
Signed-off-by: NJubin John <jubin.john@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Create a shared structure to exist between devices that share the
same ASIC.
Reviewed-by: NMitko Haralanov <mitko.haralanov@intel.com>
Reviewed-by: NEaswar Hariharan <easwar.hariharan@intel.com>
Signed-off-by: NDean Luick <dean.luick@intel.com>
Signed-off-by: NJubin John <jubin.john@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Fix the header by moving the copyright notice out of the license text
and to the top of the header. Also, update the copyright date.
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NJubin John <jubin.john@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Fix code alignment to fix checkpatch check:
CHECK: Alignment should match open parenthesis
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Reviewed-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: NJubin John <jubin.john@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Fix block comments with proper formatting to fix checkpatch warnings:
WARNING: Block comments use * on subsequent lines
WARNING: Block comments use a trailing */ on a separate line
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Reviewed-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: NJubin John <jubin.john@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Add comments describing the spinlock for spinlock_t definitions to
fix checkpatch check:
CHECK: spinlock_t definition without comment
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Reviewed-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: NJubin John <jubin.john@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Add blank line after declarations to fix checkpatch check:
CHECK: Please use a blank line after function/struct/union/enum
declarations
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Reviewed-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: NJubin John <jubin.john@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Remove the space after a cast to fix checkpatch check:
CHECK: No space is necessary after a cast
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Reviewed-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: NJubin John <jubin.john@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Remove multiple blank lines to fix checkpatch check:
CHECK: Please don't use multiple blank lines
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Reviewed-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: NJubin John <jubin.john@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Add spaces around binary operators.

Fixes checkpatch check:
CHECK: spaces preferred around that 'x'
where x is a binary operator
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Reviewed-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: NJubin John <jubin.john@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Use shared credits and dedicated credits for each VL to determine
the actual number of operational VLs.
Reviewed-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NJubin John <jubin.john@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

PIO send context mapping is changed from per-VL to QPN based.

qp to send context mapping is done using a mapping infrastructure
similar to the current vl to sdma engine mapping.
Reviewed-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: NJubin John <jubin.john@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

The change requires a new pio_busy field in the iowait structure to
track the number of outstanding pios.  The new counter together
with the sdma counter serve as the basis for a packet by packet decision
as to which egress mechanism to use.  Since packets given to different
egress mechanisms are not ordered, this scheme will preserve the order.

The iowait drain/wait mechanisms are extended for a pio case.  An
additional qp wait flag is added for the PIO drain wait case.

Currently the only pio wait is for buffers, so the no_bufs_available()
routine name is changed to pio_wait() and a third argument is passed
with one of the two pio wait flags to generalize the routine.  A module
parameter is added to hold a configurable threshold. For now, the
module parameter is zero.

A heuristic routine is added to return the func pointer of the proper
egress routine to use.

The heuristic is as follows:
- SMI always uses pio
- GSI,UD qps <= threshold use pio
- UD qps > threadhold use sdma
  o No coordination with sdma is required because order is not required
    and this qp pio count is not maintained for UD
- RC/UC ONLY packets <= threshold chose as follows:
  o If sdmas pending, use SDMA
  o Otherwise use pio and enable the pio tracking count at
    the time the pio buffer is allocated
- RC/UC ONLY packets > threshold use SDMA
  o If pio's are pending the pio_wait with the new wait flag is
    called to delay for pios to drain

The threshold is potentially reduced by the QP's mtu.

The sc_buffer_alloc() has two additional args (a callback, a void *)
which are exploited by the RC/UC cases to pass a new complete routine
and a qp *.

When the shadow ring completes the credit associated with a packet,
the new complete routine is called.  The verbs_pio_complete() will then
decrement the busy count and trigger any drain waiters in qp destroy
or reset.
Reviewed-by: NJubin John <jubin.john@intel.com>
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

The platform configuration data has been moved into the EFI variable
store where it is populated by the HFI1 option ROM. This patch pulls
the configuration data from the new location, retaining a fallback to
request_firmware.
Reviewed-by: NDean Luick <dean.luick@intel.com>
Signed-off-by: NEaswar Hariharan <easwar.hariharan@intel.com>
Signed-off-by: NJubin John <jubin.john@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Add a variable eprom_available to each device, replacing the
global of the same name.  This is to allow multiple HFI devices
with different EPROM availability to operate correctly on the
the same system.
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDean Luick <dean.luick@intel.com>
Signed-off-by: NJubin John <jubin.john@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Add a new option to the snoop ioctl which allows credits to be allocated
across all VLs. Previously only VL0 and VL15 had credits allocated.
The new option used in the ioctl HFI1_SNOOP_IOCSET_OPTS allows credits
to be allocated so that VL15 will have at least 8.5KB credits and the
other VLs will have the rest of the credits divided equally across
themselves.

The total number of credits are stored in the upper 16 bits of the
integer passed and the cumulative value should ensure that VL0 has at
least 8.5KB and each VL a minimum of 2KB + 128 bytes
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Reviewed-by: NDean Luick <dean.luick@intel.com>
Signed-off-by: NSadanand Warrier <sadanand.warrier@intel.com>
Signed-off-by: NJubin John <jubin.john@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Delete code from query_port which has been moved into rvt_query_port
Create a call back function to shut down a port which may be called from
rvt_modify_port
Signed-off-by: NHarish Chegondi <harish.chegondi@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

This patch implements LED beaconing for maintenance. A MAD packet with
the LEDInfo attribute set to 1 will enable LED beaconing with a duty
cycle of 2s on and 1.5s off. A MAD packet with the LEDInfo attribute
set to 0 will disable beaconing and return the LED to normal operation.
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NEaswar Hariharan <easwar.hariharan@intel.com>
Signed-off-by: NMitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: NJubin John <jubin.john@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Make physical state change reporting be per-device, not global
to reduce excessive reports of "physical state changed"
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDean Luick <dean.luick@intel.com>
Signed-off-by: NJubin John <jubin.john@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

When TID caching was enabled, the way the driver found
RB nodes when PSM was unprogramming TID entries was by
traversing the RB tree, looking for a match on the
RcvArray entry index.

The performance of this algorithm was not only poor but
also inconsistent depending on how many RB nodes would
have to be traversed before a match was found.

The lower performance was especially evident in cases where
there was a cache miss with the cache full, requiring the
unprogramming of several TID entries.

This commit changes how RB nodes are looked up when being
free'd by PSM to a index-based lookup into a flat array on
the index of the RcvArray entry. This turns the entire
look-up process into an O(1) algorithm.

Special care needs to be taken for situations when TID
caching is disabled. In those cases, there is no need to
insert the RB nodes into an actual RB tree. Since the entire
RcvArray management mechanism is managed by an index-based
algorithm, the RB nodes can be saved into the flat array,
making both "insertion" and "removal" faster.
Reviewed-by: NArthur Kepner <arthur.kepner@intel.com>
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NMitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: NJubin John <jubin.john@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

A patch to fix fairness issues in QP scheduling requires
n_send_schedule counter to be converted to a per cpu counter to reduce
cache misses.
Reviewed-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: NVennila Megavannan <vennila.megavannan@intel.com>
Signed-off-by: NJubin John <jubin.john@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

This patch unifies the affinity support for CPU and IRQ allocations into
a single code base. The goal is to allow the driver to make intelligent
placement decision based on an overall view of processes and IRQs across
as much of the driver as possible.

Pulling all the scattered affinity code into a single code base lays the
ground work for accomplishing the above goal.  For example, previous
implementations made user process placement decision solely based on
other user processes.  This algorithm is limited as it did not take into
account IRQ placement and could result in overloading certain CPUs.

A single code base also provides a much easier way to maintain and debug
any performance issues related to affinity.
Reviewed-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Reviewed-by: NDean Luick <dean.luick@intel.com>
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Signed-off-by: NMitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

struct hfi1_devdata contained 2 variables which represented the numa
node the device is attached to.  Remove the duplicated one.
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Signed-off-by: NMitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

hfi1 HW has a high PCIe ASPM L1 exit latency and also advertises an
acceptable latency less than actual ASPM latencies. Additional
mechanisms than those provided by BIOS/OS are therefore required to
enable/disable ASPM for hfi1 to provide acceptable power/performance
trade offs. This patch adds this support.

By means of a module parameter ASPM can be either (a) always enabled
(power save mode) (b) always disabled (performance mode) (c)
enabled/disabled dynamically. The dynamic mode implements two
heuristics to alleviate possible problems with high ASPM L1 exit
latency. ASPM is normally enabled but is disabled if (a) there are any
active user space PSM contexts, or (b) for verbs, ASPM is disabled as
interrupt activity for a context starts to increase.

A few more points about the verbs implementation. In order to reduce
lock/cache contention between multiple verbs contexts, some processing
is done at the context layer before contending for device layer
locks. ASPM is disabled when two interrupts for a context happen
within 1 millisec. A timer is scheduled which will re-enable ASPM
after 1 second should the interrupt activity cease. Normally, every
interrupt, or interrupt-pair should push the timer out
further. However, since this might increase the processing load per
interrupt, pushing the timer out is postponed for half a second. If
after half a second we get two interrupts within 1 millisec the timer
is pushed out by another second.

Finally, the kernel ASPM API is not used in this patch. This is
because this patch does several non-standard things as SW workarounds
for HW issues. As mentioned above, it enables ASPM even when advertised
actual latencies are greater than acceptable latencies. Also, whereas
the kernel API only allows drivers to disable ASPM from driver probe,
this patch enables/disables ASPM directly from interrupt context. Due
to these reasons the kernel ASPM API was not used.
Reviewed-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Reviewed-by: NDean Luick <dean.luick@intel.com>
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Signed-off-by: NAshutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Add a per port sysfs paramter to toggle cc_prescan/Fast ECN Detection and
remove the Kconfig option which was previously used to control this.

While am updating the sysfs documentation, fix the name of CCMgtA.
Reviewed-by: NArthur Kepner <arthur.kepner@intel.com>
Reviewed-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: NVennila Megavannan <vennila.megavannan@intel.com>
Signed-off-by: NIra Weiny <ira.weiny@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>