As per the current i915 Driver load sequence, debugfs registration is done
at the end and so the relay channel debugfs file is also created after that
but the GuC firmware is loaded much earlier in the sequence.
As a result Driver could miss capturing the boot-time logs of GuC firmware
if there are flush interrupts from the GuC side.
Relay has a provision to support early logging where initially only relay
channel can be created, to have buffers for storing logs, and later on
channel can be associated with a debugfs file at appropriate time.
Have availed that, which allows Driver to capture boot time logs also,
which can be collected once Userspace comes up.

v2:
- Remove the couple of FIXMEs, as now the relay channel will be created
  early before enabling the flush interrupts, so no possibility of relay
  channel pointer being modified & read at the same time from 2 different
  execution contexts.
- Rebase.

v3:
- Add a comment to justiy setting 'is_global' before the NULL check on the
  parent directory dentry pointer.
Suggested-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Akash Goel <akash.goel@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

To ensure that we always get the up-to-date data from log buffer, its
better to access the buffer through an uncached CPU mapping. Also the way
buffer is accessed from GuC & Host side, manually doing cache flush may
not be effective always if cached CPU mapping is used. In order to avoid
any performance drop & have fast reads from the GuC log buffer, used SSE4.1
movntdqa based memcpy function i915_memcpy_from_wc, as copying using
movntqda from WC type memory is almost as fast as reading from WB memory.
This way log buffer sampling time will not get increased and so would be
able to deal with the flush interrupt storm when GuC is generating logs at
a very high rate.
Ideally SSE 4.1 should be present on all chipsets supporting GuC based
submisssions, but if not then logging will not be enabled.

v2: Rebase.

v3: Squash the WC type vmalloc mapping patch with this patch. (Chris)
Suggested-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Akash Goel <akash.goel@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

This patch provides debugfs interface i915_guc_output_control for
on the fly enabling/disabling of logging in GuC firmware and controlling
the verbosity level of logs.
The value written to the file, should have bit 0 set to enable logging and
bits 4-7 should contain the verbosity info.

v2: Add a forceful flush, to collect left over logs, on disabling logging.
    Useful for Validation.

v3: Besides minor cleanup, implement read method for the debugfs file and
    set the guc_log_level to -1 when logging is disabled. (Tvrtko)

v4: Minor cleanup & rebase. (Tvrtko)

v5:
- Lock struct_mutex after the NULL check for guc log buffer vma. (Chris)
- Rebase.
Signed-off-by: Sagar Arun Kamble <sagar.a.kamble@intel.com>
Signed-off-by: Akash Goel <akash.goel@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

GuC firmware sends a flush interrupt to Host when the log buffer is half
full and at that time only it updates the log buffer state.
But in certain cases, as described below, it could be useful to have all
that even when log buffer is only partially full. For that there is a force
log buffer flush Host2GuC action supported by GuC firmware.

For Validation requirements, a forceful flush is needed to collect the
left over logs on disabling logging. The same can be done before proceeding
with GPU/GuC reset as there could be some data in log buffer which is yet
to be captured and those logs would be particularly useful to understand
that why the reset was initiated.
Signed-off-by: Sagar Arun Kamble <sagar.a.kamble@intel.com>
Signed-off-by: Akash Goel <akash.goel@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

Added the dump of GuC log buffer to i915 error state, as the contents of
GuC log buffer would also be useful to determine that why the GPU reset
was triggered.

v2:
- For uniformity use existing helper function print_error_obj() to
  dump out contents of GuC log buffer, pretty printing is better left
  to userspace. (Chris)
- Skip the dumping of GuC log buffer when logging is disabled as it
  won't be of any use.
- Rebase.

v3: Rebase.
Suggested-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Akash Goel <akash.goel@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

In cases where GuC generate logs at a very high rate, correspondingly
the rate of flush interrupts is also very high.
So far total 8 pages were allocated for storing both ISR & DPC logs.
As per the half-full draining protocol followed by GuC, by doubling
the number of pages, the frequency of flush interrupts can be cut down
to almost half, which then helps in reducing the logging overhead.
So now allocating 8 pages apiece for ISR & DPC logs.
This also helps in reducing the output log file size, apart from
reducing the flush interrupt count. With the original settings,
44 KB was needed for one snapshot. With modified settings, 76 KB is
needed for a snapshot which will be equivalent to 2 snapshots of the
original setting. So 12KB saving, every 88 KB, over the original setting.
Suggested-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Akash Goel <akash.goel@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

GuC firmware sends an interrupt to flush the log buffer when it becomes
half full, so Driver doesn't really need to sample the complete buffer
and can just copy only the newly written data by GuC into the local
buffer, i.e. as per the read & write pointer values.
Moreover the flush interrupt would generally come for one type of log
buffer, when it becomes half full, so at that time the other 2 types of
log buffer would comparatively have much lesser unread data in them.
In case of overflow reported by GuC, Driver do need to copy the entire
buffer as the whole buffer would contain the unread data.

v2: Rebase.

v3: Fix the blooper of doing the copy twice. (Tvrtko)

v4: Add curlies for 'else' case also, matching the 'if'. (Tvrtko)
Signed-off-by: Akash Goel <akash.goel@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

GuC firmware sends an interrupt to flush the log buffer when it
becomes half full. GuC firmware also tracks how many times the
buffer overflowed.
It would be useful to maintain a statistics of how many flush
interrupts were received and for which type of log buffer,
along with the overflow count of each buffer type.
Augmented i915_log_info debugfs to report back these statistics.

v2:
- Update the logic to detect multiple overflows between the 2
  flush interrupts and also log a message for overflow (Tvrtko)
- Track the number of times there was no free sub buffer to capture
  the GuC log buffer. (Tvrtko)

v3:
- Fix the printf field width for overflow counter, set it to 10 as per the
  max value of u32, which takes 10 digits in decimal form. (Tvrtko)

v4:
- Move the log buffer overflow handling to a new function for better
  readability. (Tvrtko)
Signed-off-by: Akash Goel <akash.goel@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

With the addition of new Host2GuC actions related to GuC logging, there
is a need of a lock to serialize them, as they can execute concurrently
with each other and also with other existing actions.

v2: Use mutex in place of spinlock to serialize, as sleep can happen
    while waiting for the action's response from GuC. (Tvrtko)

v3: To conform to the general rules, acquire mutex before taking the
    forcewake. (Tvrtko)
Signed-off-by: Akash Goel <akash.goel@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

Added a new debugfs interface '/sys/kernel/debug/dri/guc_log' for the
User to capture GuC firmware logs. Availed relay framework to implement
the interface, where Driver will have to just use a relay API to store
snapshots of the GuC log buffer in the buffer managed by relay.
The snapshot will be taken when GuC firmware sends a log buffer flush
interrupt and up to four snapshots could be stored in the relay buffer.
The relay buffer will be operated in a mode where it will overwrite the
data not yet collected by User.
Besides mmap method, through which User can directly access the relay
buffer contents, relay also supports the 'poll' method. Through the 'poll'
call on log file, User can come to know whenever a new snapshot of the
log buffer is taken by Driver, so can run in tandem with the Driver and
capture the logs in a sustained/streaming manner, without any loss of data.

v2: Defer the creation of relay channel & associated debugfs file, as
    debugfs setup is now done at the end of i915 Driver load. (Chris)

v3:
- Switch to no-overwrite mode for relay.
- Fix the relay sub buffer switching sequence.

v4:
- Update i915 Kconfig to select RELAY config. (TvrtKo)
- Log a message when there is no sub buffer available to capture
  the GuC log buffer. (Tvrtko)
- Increase the number of relay sub buffers to 8 from 4, to have
  sufficient buffering for boot time logs

v5:
- Fix the alignment, indentation issues and some minor cleanup. (Tvrtko)
- Update the comment to elaborate on why a relay channel has to be
  associated with the debugfs file. (Tvrtko)

v6:
- Move the write to 'is_global' after the NULL check on parent directory
  dentry pointer. (Tvrtko)

v7: Add a BUG_ON to validate relay buffer allocation size. (Chris)

Testcase: igt/tools/intel_guc_logger
Suggested-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Sourab Gupta <sourab.gupta@intel.com>
Signed-off-by: Akash Goel <akash.goel@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

GuC ukernel sends an interrupt to Host to flush the log buffer
and expects Host to correspondingly update the read pointer
information in the state structure, once it has consumed the
log buffer contents by copying them to a file or buffer.
Even if Host couldn't copy the contents, it can still update the
read pointer so that logging state is not disturbed on GuC side.

v2:
- Use a dedicated workqueue for handling flush interrupt. (Tvrtko)
- Reduce the overall log buffer copying time by skipping the copy of
  crash buffer area for regular cases and copying only the state
  structure data in first page.

v3:
 - Create a vmalloc mapping of log buffer. (Chris)
 - Cover the flush acknowledgment under rpm get & put.(Chris)
 - Revert the change of skipping the copy of crash dump area, as
   not really needed, will be covered by subsequent patch.

v4:
 - Destroy the wq under the same condition in which it was created,
   pass dev_piv pointer instead of dev to newly added GuC function,
   add more comments & rename variable for clarity. (Tvrtko)

v5:
- Allocate & destroy the dedicated wq, for handling flush interrupt,
  from the setup/teardown routines of GuC logging. (Chris)
- Validate the log buffer size value retrieved from state structure
  and do some minor cleanup. (Tvrtko)
- Fix error/warnings reported by checkpatch. (Tvrtko)
- Rebase.

v6:
 - Remove the interrupts_enabled check from guc_capture_logs_work, need
   to process that last work item also, queued just before disabling the
   interrupt as log buffer flush interrupt handling is a bit different
   case where GuC is actually expecting an ACK from host, which should be
   provided to keep the logging going.
   Sync against the work will be done by caller disabling the interrupt.
 - Don't sample the log buffer size value from state structure, directly
   use the expected value to move the pointer & do the copy and that cannot
   go wrong (out of bounds) as Driver only allocated the log buffer and the
   relay buffers. Driver should refrain from interpreting the log packet,
   as much possible and let Userspace parser detect the anomaly. (Chris)

v7:
- Use switch statement instead of 'if else' for retrieving the GuC log
  buffer size. (Tvrtko)
- Refactored the log buffer copying function and shortended the name of
  couple of variables for better readability. (Tvrtko)

v8:
- Make the dedicated wq as a high priority one to further reduce the
  turnaround time of handing log buffer flush event from GuC.
Signed-off-by: Sagar Arun Kamble <sagar.a.kamble@intel.com>
Signed-off-by: Akash Goel <akash.goel@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

There are certain types of interrupts which Host can receive from GuC.
GuC ukernel sends an interrupt to Host for certain events, like for
example retrieve/consume the logs generated by ukernel.
This patch adds support to receive interrupts from GuC but currently
enables & partially handles only the interrupt sent by GuC ukernel.
Future patches will add support for handling other interrupt types.

v2:
- Use common low level routines for PM IER/IIR programming (Chris)
- Rename interrupt functions to gen9_xxx from gen8_xxx (Chris)
- Replace disabling of wake ref asserts with rpm get/put (Chris)

v3:
- Update comments for more clarity. (Tvrtko)
- Remove the masking of GuC interrupt, which was kept masked till the
  start of bottom half, its not really needed as there is only a
  single instance of work item & wq is ordered. (Tvrtko)

v4:
- Rebase.
- Rename guc_events to pm_guc_events so as to be indicative of the
  register/control block it is associated with. (Chris)
- Add handling for back to back log buffer flush interrupts.

v5:
- Move the read & clearing of register, containing Guc2Host message
  bits, outside the irq spinlock. (Tvrtko)

v6:
- Move the log buffer flush interrupt related stuff to the following
  patch so as to do only generic bits in this patch. (Tvrtko)
- Rebase.

v7:
- Remove the interrupts_enabled check from gen9_guc_irq_handler, want to
  process that last interrupt also before disabling the interrupt, sync
  against the work queued by irq handler will be done by caller disabling
  the interrupt.
Signed-off-by: Sagar Arun Kamble <sagar.a.kamble@intel.com>
Signed-off-by: Akash Goel <akash.goel@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

So far PM IER/IIR/IMR registers were being used only for Turbo related
interrupts. But interrupts coming from GuC also use the same set.
As a precursor to supporting GuC interrupts, added new low level routines
so as to allow sharing the programming of PM IER/IIR/IMR registers between
Turbo & GuC.
Also similar to PM IMR, maintaining a bitmask for PM IER register, to allow
easy sharing of it between Turbo & GuC without involving a rmw operation.

v2:
- For appropriateness & avoid any ambiguity, rename old functions
  enable/disable pm_irq to mask/unmask pm_irq and rename new functions
  enable/disable pm_interrupts to enable/disable pm_irq. (Tvrtko)
- Use u32 in place of uint32_t. (Tvrtko)

v3:
- Rename the fields pm_irq_mask & pm_ier_mask and do some cleanup. (Chris)
- Rebase.

v4: Fix the inadvertent disabling of User interrupt for VECS ring causing
    failure for certain IGTs.

v5: Use dev_priv with HAS_VEBOX macro. (Tvrtko)
Suggested-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Akash Goel <akash.goel@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

So far there were 2 fields related to GuC logs in 'intel_guc' structure.
For the support of capturing GuC logs & storing them in a local buffer,
multiple new fields would have to be added. This warrants a separate
structure to contain the fields related to GuC logging state.
Added a new structure 'intel_guc_log' and instance of it inside
'intel_guc' structure.

v2: Rebase.
Signed-off-by: Akash Goel <akash.goel@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

The first page of the GuC log buffer contains state info or meta data
which is required to parse the logs contained in the subsequent pages.
The structure representing the state info is added to interface file
as Driver would need to handle log buffer flush interrupts from GuC.
Added an enum for the different message/event types that can be send
by the GuC ukernel to Host.
Also added 2 new Host to GuC action types to inform GuC when Host has
flushed the log buffer and forcefuly cause the GuC to send a new
log buffer flush interrupt.

v2:
- Make documentation of log buffer state structure more elaborate &
  rename LOGBUFFERFLUSH action to LOG_BUFFER_FLUSH for consistency.(Tvrtko)

v3: Add GuC log buffer layout diagram for more clarity.
Signed-off-by: Sagar Arun Kamble <sagar.a.kamble@intel.com>
Signed-off-by: Akash Goel <akash.goel@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

GuC Log buffer allocation was tied up with verbosity level module param
i915.guc_log_level. User would be given a provision to enable firmware
logging at runtime, through a host2guc action, and not necessarily during
Driver load time. But the address of log buffer can be passed only in
init params, at firmware load time, so GuC has to be reset and firmware
needs to be reloaded to pass the log buffer address at runtime.
To avoid reset of GuC & reload of firmware, allocation of log buffer will
be done always but logging would be enabled initially on GuC side based on
the value of module parameter guc_log_level.

v2: Update commit message to describe the constraint with allocation of
    log buffer at runtime. (Tvrtko)

v3: Rebase.
Signed-off-by: Sagar Arun Kamble <sagar.a.kamble@intel.com>
Signed-off-by: Akash Goel <akash.goel@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

Backmerge because Chris Wilson needs the very latest&greates of
Gustavo Padovan's sync_file work, specifically the refcounting changes
from:

commit 30cd85dd
Author: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Date:   Wed Oct 19 15:48:32 2016 -0200

    dma-buf/sync_file: hold reference to fence when creating sync_file

Also good to sync in general since git tends to get confused with the
cherry-picking going on.
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>

- first slice of the gvt device model (Zhenyu et al)
- compression support for gpu error states (Chris)
- sunset clause on gpu errors resulting in dmesg noise telling users
  how to report them
- .rodata diet from Tvrtko
- switch over lots of macros to only take dev_priv (Tvrtko)
- underrun suppression for dp link training (Ville)
- lspcon (hmdi 2.0 on skl/bxt) support from Shashank Sharma, polish
  from Jani
- gen9 wm fixes from Paulo&Lyude
- updated ddi programming for kbl (Rodrigo)
- respect alternate aux/ddc pins (from vbt) for all ddi ports (Ville)

* tag 'drm-intel-next-2016-10-24' of git://anongit.freedesktop.org/drm-intel: (227 commits)
  drm/i915: Update DRIVER_DATE to 20161024
  drm/i915: Stop setting SNB min-freq-table 0 on powersave setup
  drm/i915/dp: add lane_count check in intel_dp_check_link_status
  drm/i915: Fix whitespace issues
  drm/i915: Clean up DDI DDC/AUX CH sanitation
  drm/i915: Respect alternate_ddc_pin for all DDI ports
  drm/i915: Respect alternate_aux_channel for all DDI ports
  drm/i915/gen9: Remove WaEnableYV12BugFixInHalfSliceChicken7
  drm/i915: KBL - Recommended buffer translation programming for DisplayPort
  drm/i915: Move down skl/kbl ddi iboost and n_edp_entires fixup
  drm/i915: Add a sunset clause to GPU hang logging
  drm/i915: Stop reporting error details in dmesg as well as the error-state
  drm/i915/gvt: do not ignore return value of create_scratch_page
  drm/i915/gvt: fix spare warnings on odd constant _Bool cast
  drm/i915/gvt: mark symbols static where possible
  drm/i915/gvt: fix sparse warnings on different address spaces
  drm/i915/gvt: properly access enabled intel_engine_cs
  drm/i915/gvt: Remove defunct vmap_batch()
  drm/i915/gvt: Use common mapping routines for shadow_bb object
  drm/i915/gvt: Use common mapping routines for indirect_ctx object
  ...

First -misc pull for 4.10:
- drm_format rework from Laurent
- reservation patches from Chris that missed 4.9.
- aspect ratio support in infoframe helpers and drm mode/edid code
  (Shashank Sharma)
- rotation rework from Ville (first parts at least)
- another attempt at the CRC debugfs interface from Tomeu
- piles and piles of misc patches all over

* tag 'topic/drm-misc-2016-10-24' of git://anongit.freedesktop.org/drm-intel: (55 commits)
  drm: Use u64 for intermediate dotclock calculations
  drm/i915: Use the per-plane rotation property
  drm/omap: Use per-plane rotation property
  drm/omap: Set rotation property initial value to BIT(DRM_ROTATE_0) insted of 0
  drm/atmel-hlcdc: Use per-plane rotation property
  drm/arm: Use per-plane rotation property
  drm: Add support for optional per-plane rotation property
  drm/atomic: Reject attempts to use multiple rotation angles at once
  drm: Add drm_rotation_90_or_270()
  dma-buf/sync_file: hold reference to fence when creating sync_file
  drm/virtio: kconfig: Fixup white space.
  drm/fence: release fence reference when canceling event
  drm/i915: Handle early failure during intel_get_load_detect_pipe
  drm/fb_cma_helper: do not free fbdev if there is none
  drm: fix sparse warnings on undeclared symbols in crc debugfs
  gpu: Remove depends on RESET_CONTROLLER when not a provider
  i915: don't call drm_atomic_state_put on invalid pointer
  drm: Don't export the drm_fb_get_bpp_depth() function
  drm/arm: mali-dp: Replace drm_fb_get_bpp_depth() with drm_format_plane_cpp()
  drm: vmwgfx: Replace drm_fb_get_bpp_depth() with drm_format_info()
  ...

Its size is 11:0 instead of 10:0. Found by inspecting the spec. I'm
not aware of any real-world IGT failures caused by this.
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1477065346-13736-2-git-send-email-paulo.r.zanoni@intel.com

Broadwell and newer actually compress up to 2560 lines instead of 2048
(as documented in the FBC_CTL page). If we don't take this into
consideration we end up reserving too little stolen memory for the
CFB, so we may allocate something else (such as a ring) right after
what we reserved, and the hardware will overwrite it with the contents
of the CFB when FBC is active, causing GPU hangs. Another possibility
is that the CFB may be allocated at the very end of the available
space, so the CFB will overlap the reserved stolen area, leading to
FIFO underruns.

This bug has always been a problem on BDW (the only affected platform
where FBC is enabled by default), but it's much easier to reproduce
since the following commit:
    commit c58b735f
    Author: Chris Wilson <chris@chris-wilson.co.uk>
    Date:   Thu Aug 18 17:16:57 2016 +0100
        drm/i915: Allocate rings from stolen

Of course, you can only reproduce the bug if your screen is taller
than 2048 lines.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=98213
Fixes: a98ee793 ("drm/i915/fbc: enable FBC by default on HSW and BDW")
Cc: <stable@vger.kernel.org> # v4.6+
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1477065346-13736-1-git-send-email-paulo.r.zanoni@intel.com

At the moment, we have dependency on the RPM as a barrier itself in both
i915_gem_release_all_mmaps() and i915_gem_restore_fences().
i915_gem_restore_fences() is also called along !runtime pm paths, but we
can move the markup of lost fences alongside releasing the mmaps into a
common i915_gem_runtime_suspend(). This has the advantage of locating
all the tricky barrier dependencies into one location.

v2: Just mark the fence as invalid (fence->dirty) so that upon waking we
will be sure to clear the fence after use, or restore it to the correct
value before use. This makes sure that if the fence is left intact
across the sleep, we do not leave it pointing to a region of GTT for the
next unsuspecting user.
Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Imre Deak <imre.deak@linux.intel.com>
Reviewed-by: Imre Deak <imre.deak@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161024124218.18252-5-chris@chris-wilson.co.uk

We only used the RPM sequence checking inside the lowlevel GTT
accessors, when we had to rely on callers taking the wakeref on our
behalf. Now that we take the RPM wakeref inside the GTT management
routines themselves, we can forgo the sanitycheck of the callers.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Imre Deak <imre.deak@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161024124218.18252-4-chris@chris-wilson.co.uk

Now that we have reduced the access to the list to either (a) under the
struct_mutex whilst holding the RPM wakeref (so that concurrent writers to
the list are serialised by struct_mutex) and (b) under the atomic
runtime suspend (which cannot run concurrently with any other accessor due
to the atomic nature of the runtime suspend) we can remove the extra
locking around the list itself.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161024124218.18252-3-chris@chris-wilson.co.uk

We can remove the false coupling between RPM and struct mutex by the
observation that we can use the RPM wakeref as the barrier around user
mmap access. That is as we tear down the user's PTE atomically from
within rpm suspend and then to fault in new PTE requires the rpm
wakeref, means that no user access is possible through those PTE without
RPM being awake. Having made that observation, we can then remove the
presumption of having to take rpm outside of struct_mutex and so allow
fine grained acquisition of a wakeref around hw access rather than
having to remember to acquire the wakeref early on.

v2: Rejig placement of the new intel_runtime_pm_get() to be as tight
as possible around the GTT pread/pwrite.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Daniel Vetter <daniel@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161024124218.18252-2-chris@chris-wilson.co.uk

We want to decouple RPM and struct_mutex, but currently RPM has to walk
the list of bound objects and remove userspace mmapping before we
suspend (otherwise userspace may continue to access the GTT whilst it is
powered down). This currently requires the struct_mutex to walk the
bound_list, but if we move that to a separate list and lock we can take
the first step towards removing the struct_mutex.

v2: Split runtime suspend unmapping vs regular unmapping, to make the
locking (and barriers) clearer. Add the object to the userfault_list
prior to inserting the first PTE, the race between add/revoke depends
upon struct_mutex for regular unmappings and rpm for runtime-suspend.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> #v1
Link: http://patchwork.freedesktop.org/patch/msgid/20161024124218.18252-1-chris@chris-wilson.co.uk

We haven't required AGP since 3e99a6b9 ("drm/i915: Stop depending
upon CONFIG_AGP_INTEL"). Split/rearrange the paragraphs a bit while at
it.
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1477041257-8219-1-git-send-email-jani.nikula@intel.com

The previous code would wait for fences on the framebuffer from the old
plane state to complete, rather than the new, so you would see tearing
everywhere. Fix this to wait on the new state before we make it active.
Signed-off-by: Daniel Stone <daniels@collabora.com>
Fixes: 94f05024 ("drm/i915: nonblocking commit")
Cc: stable@vger.kernel.org
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161021144454.6288-1-daniels@collabora.com

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

Pull UBI[FS] fixes from Richard Weinberger:
 "This contains fixes for issues in both UBI and UBIFS:

   - Fallout from the merge window, refactoring UBI code introduced some
     issues.

   - Fixes for an UBIFS readdir bug which can cause getdents() to busy
     loop for ever and a bug in the UBIFS xattr code"

* tag 'upstream-4.9-rc2' of git://git.infradead.org/linux-ubifs:
  ubifs: Abort readdir upon error
  UBI: Fix crash in try_recover_peb()
  ubi: fix swapped arguments to call to ubi_alloc_aeb
  ubifs: Fix xattr_names length in exit paths
  ubifs: Rename ubifs_rename2

Pull ext4 fixes from Ted Ts'o:
 "A few bug fixes and add some missing KERN_CONT annotations"

* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: add missing KERN_CONT to a few more debugging uses
  fscrypto: lock inode while setting encryption policy
  ext4: correct endianness conversion in __xattr_check_inode()
  fscrypto: make XTS tweak initialization endian-independent
  ext4: do not advertise encryption support when disabled
  jbd2: fix incorrect unlock on j_list_lock
  ext4: super.c: Update logging style using KERN_CONT

Pull SCSI target fixes from Nicholas Bellinger:
 "Here are the outstanding target-pending fixes for v4.9-rc2.

  This includes:

   - Fix v4.1.y+ reference leak regression with concurrent TMR
     ABORT_TASK + session shutdown. (Vaibhav Tandon)

   - Enable tcm_fc w/ SCF_USE_CPUID to avoid host exchange timeouts
     (Hannes)

   - target/user error sense handling fixes. (Andy + MNC + HCH)

   - Fix iscsi-target NOP_OUT error path iscsi_cmd descriptor leak
     (Varun)

   - Two EXTENDED_COPY SCSI status fixes for ESX VAAI (Dinesh Israni +
     Nixon Vincent)

   - Revert a v4.8 residual overflow change, that breaks sg_inq with
     small allocation lengths.

  There are a number of folks stress testing the v4.1.y regression fix
  in their environments, and more folks doing iser-target I/O stress
  testing atop recent v4.x.y code.

  There is also one v4.2.y+ RCU conversion regression related to
  explicit NodeACL configfs changes, that is still being tracked down"

* git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending:
  target/tcm_fc: use CPU affinity for responses
  target/tcm_fc: Update debugging statements to match libfc usage
  target/tcm_fc: return detailed error in ft_sess_create()
  target/tcm_fc: print command pointer in debug message
  target: fix potential race window in target_sess_cmd_list_waiting()
  Revert "target: Fix residual overflow handling in target_complete_cmd_with_length"
  target: Don't override EXTENDED_COPY xcopy_pt_cmd SCSI status code
  target: Make EXTENDED_COPY 0xe4 failure return COPY TARGET DEVICE NOT REACHABLE
  target: Re-add missing SCF_ACK_KREF assignment in v4.1.y
  iscsi-target: fix iscsi cmd leak
  iscsi-target: fix spelling mistake "Unsolicitied" -> "Unsolicited"
  target/user: Fix comments to not refer to data ring
  target/user: Return an error if cmd data size is too large
  target/user: Use sense_reason_t in tcmu_queue_cmd_ring

Merge tag 'hwmon-for-linus-v4.9-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging

Pull hwmon fixes from Guenter Roeck:
 "Couple of hwmon fixes:

  Fix a potential ERR_PTR dereference in max31790 driver, and handle
  temperature readings below 0 in adm9240 driver"

* tag 'hwmon-for-linus-v4.9-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
  hwmon: (max31790) potential ERR_PTR dereference
  hwmon: (adm9240) handle temperature readings below 0

Pull IPMI updates from Corey Minyard:
 "A small bug fix and a new driver for acting as an IPMI device.

  I was on vacation during the merge window (a long vacation) but this
  is a bug fix that should go in and a new driver that shouldn't hurt
  anything.

  This has been in linux-next for a month or so"

* tag 'for-linus-4.9-2' of git://git.code.sf.net/p/openipmi/linux-ipmi:
  ipmi: fix crash on reading version from proc after unregisted bmc
  ipmi/bt-bmc: remove redundant return value check of platform_get_resource()
  ipmi/bt-bmc: add a dependency on ARCH_ASPEED
  ipmi: Fix ioremap error handling in bt-bmc
  ipmi: add an Aspeed BT IPMI BMC driver

Pull timer updates from Thomas Gleixner:
 "This updates contains:

   - A revert which addresses a boot failure on ARM Sun5i platforms

   - A new clocksource driver, which has been delayed beyond rc1 due to
     an interrupt driver issue which was unearthed by this driver. The
     debugging of that issue and the discussion about the proper
     solution made this driver miss the merge window. There is no point
     in delaying it for a full cycle as it completes the basic mainline
     support for the new JCore platform and does not create any risk
     outside of that platform"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  Revert "clocksource/drivers/timer_sun5i: Replace code by clocksource_mmio_init"
  clocksource: Add J-Core timer/clocksource driver
  of: Add J-Core timer bindings

Pull x86 fixes from Ingo Molnar:
 "Three fixes, a hw-enablement and a cross-arch fix/enablement change:

   - SGI/UV fix for older platforms

   - x32 signal handling fix

   - older x86 platform bootup APIC fix

   - AVX512-4VNNIW (Neural Network Instructions) and AVX512-4FMAPS
     (Multiply Accumulation Single precision instructions) enablement.

   - move thread_info back into x86 specific code, to make life easier
     for other architectures trying to make use of
     CONFIG_THREAD_INFO_IN_TASK_STRUCT=y"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/boot/smp: Don't try to poke disabled/non-existent APIC
  sched/core, x86: Make struct thread_info arch specific again
  x86/signal: Remove bogus user_64bit_mode() check from sigaction_compat_abi()
  x86/platform/UV: Fix support for EFI_OLD_MEMMAP after BIOS callback updates
  x86/cpufeature: Add AVX512_4VNNIW and AVX512_4FMAPS features
  x86/vmware: Skip timer_irq_works() check on VMware

Pull vmap stack fixes from Ingo Molnar:
 "This is fallout from CONFIG_HAVE_ARCH_VMAP_STACK=y on x86: stack
  accesses that used to be just somewhat questionable are now totally
  buggy.

  These changes try to do it without breaking the ABI: the fields are
  left there, they are just reporting zero, or reporting narrower
  information (the maps file change)"

* 'mm-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  mm: Change vm_is_stack_for_task() to vm_is_stack_for_current()
  fs/proc: Stop trying to report thread stacks
  fs/proc: Stop reporting eip and esp in /proc/PID/stat
  mm/numa: Remove duplicated include from mprotect.c

Pull irq fixes from Ingo Molnar:
 "Mostly irqchip driver fixes, plus a symbol export"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  kernel/irq: Export irq_set_parent()
  irqchip/gic: Add missing \n to CPU IF adjustment message
  irqchip/jcore: Don't show Kconfig menu item for driver
  irqchip/eznps: Drop pointless static qualifier in nps400_of_init()
  irqchip/gic-v3-its: Fix entry size mask for GITS_BASER
  irqchip/gic-v3-its: Fix 64bit GIC{R,ITS}_TYPER accesses

Pull EFI fixes from Ingo Molnar:
 "Add Ard Biesheuvel as EFI co-maintainer, plus fix an ARM build bug
  with older toolchains"

* 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  efi/arm: Fix absolute relocation detection for older toolchains
  MAINTAINERS: Add myself as EFI maintainer