If the user requires patching of their batch or auxiliary buffers, we
currently make the alterations on the cpu. If they are active on the GPU
at the time, we wait under the struct_mutex for them to finish executing
before we rewrite the contents. This happens if shared relocation trees
are used between different contexts with separate address space (and the
buffers then have different addresses in each), the 3D state will need
to be adjusted between execution on each context. However, we don't need
to use the CPU to do the relocation patching, as we could queue commands
to the GPU to perform it and use fences to serialise the operation with
the current activity and future - so the operation on the GPU appears
just as atomic as performing it immediately. Performing the relocation
rewrites on the GPU is not free, in terms of pure throughput, the number
of relocations/s is about halved - but more importantly so is the time
under the struct_mutex.

v2: Break out the request/batch allocation for clearer error flow.
v3: A few asserts to ensure rq ordering is maintained
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>

Currently, the last object in the execlist is the always the batch.
However, when building the batch buffer we often know the batch object
first and if we can use the first slot in the execlist we can emit
relocation instructions relative to it immediately and avoid a separate
pass to adjust the relocations to point to the last execlist slot.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>

This simply hides the EAGAIN caused by userptr when userspace causes
resource contention. However, it is quite beneficial with highly
contended userptr users as we avoid repeating the setup costs and
kernel-user context switches.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Michał Winiarski <michal.winiarski@intel.com>

When choosing a slot for an execbuffer, we ideally want to use the same
address as last time (so that we don't have to rebind it) and the same
address as expected by the user (so that we don't have to fixup any
relocations pointing to it). If we first try to bind the incoming
execbuffer->offset from the user, or the currently bound offset that
should hopefully achieve the goal of avoiding the rebind cost and the
relocation penalty. However, if the object is not currently bound there
we don't want to arbitrarily unbind an object in our chosen position and
so choose to rebind/relocate the incoming object instead. After we
report the new position back to the user, on the next pass the
relocations should have settled down.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtien@linux.intel.com>

If we take a reference to the object/vma when it is first used in an
execbuf, we can keep that reference until the object's file-local handle
is closed. Thereby saving a frequent ref/unref pair.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>

The major scaling bottleneck in execbuffer is the processing of the
execobjects. Creating an auxiliary list is inefficient when compared to
using the execobject array we already have allocated.

Reservation is then split into phases. As we lookup up the VMA, we
try and bind it back into active location. Only if that fails, do we add
it to the unbound list for phase 2. In phase 2, we try and add all those
objects that could not fit into their previous location, with fallback
to retrying all objects and evicting the VM in case of severe
fragmentation. (This is the same as before, except that phase 1 is now
done inline with looking up the VMA to avoid an iteration over the
execobject array. In the ideal case, we eliminate the separate reservation
phase). During the reservation phase, we only evict from the VM between
passes (rather than currently as we try to fit every new VMA). In
testing with Unreal Engine's Atlantis demo which stresses the eviction
logic on gen7 class hardware, this speed up the framerate by a factor of
2.

The second loop amalgamation is between move_to_gpu and move_to_active.
As we always submit the request, even if incomplete, we can use the
current request to track active VMA as we perform the flushes and
synchronisation required.

The next big advancement is to avoid copying back to the user any
execobjects and relocations that are not changed.

v2: Add a Theory of Operation spiel.
v3: Fall back to slow relocations in preparation for flushing userptrs.
v4: Document struct members, factor out eb_validate_vma(), add a few
more comments to explain some magic and hide other magic behind macros.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>

If we write a relocation into the buffer, we require our own implicit
synchronisation added after the start of the execbuf, outside of the
user's control. As we may end up clflushing, or doing the patch itself
on the GPU, asynchronously we need to look at the implicit serialisation
on obj->resv and hence need to disable EXEC_OBJECT_ASYNC for this
object.

If the user does trigger a stall for relocations, we make sure the stall
is complete enough so that the batch is not submitted before we complete
those relocations.

Fixes: 77ae9957 ("drm/i915: Enable userspace to opt-out of implicit fencing")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Jason Ekstrand <jason@jlekstrand.net>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>

We can simplify our tracking of pending writes in an execbuf to the
single bit in the vma->exec_entry->flags, but that requires the
relocation function knowing the object's vma. Pass it along.

Note we have only been using a single bit to track flushing since

commit cc889e0f
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date:   Wed Jun 13 20:45:19 2012 +0200

    drm/i915: disable flushing_list/gpu_write_list

unconditionally flushed all render caches before the breadcrumb and

commit 6ac42f41
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date:   Sat Jul 21 12:25:01 2012 +0200

    drm/i915: Replace the complex flushing logic with simple invalidate/flush all

did away with the explicit GPU domain tracking. This was then codified
into the ABI with NO_RELOC in

commit ed5982e6
Author: Daniel Vetter <daniel.vetter@ffwll.ch> # Oi! Patch stealer!
Date:   Thu Jan 17 22:23:36 2013 +0100

    drm/i915: Allow userspace to hint that the relocations were known
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>

The advent of full-ppgtt lead to an extra indirection between the object
and its binding. That extra indirection has a noticeable impact on how
fast we can convert from the user handles to our internal vma for
execbuffer. In order to bypass the extra indirection, we use a
resizable hashtable to jump from the object to the per-ctx vma.
rhashtable was considered but we don't need the online resizing feature
and the extra complexity proved to undermine its usefulness. Instead, we
simply reallocate the hastable on demand in a background task and
serialize it before iterating.

In non-full-ppgtt modes, multiple files and multiple contexts can share
the same vma. This leads to having multiple possible handle->vma links,
so we only use the first to establish the fast path. The majority of
buffers are not shared and so we should still be able to realise
speedups with multiple clients.

v2: Prettier names, more magic.
v3: Many style tweaks, most notably hiding the misuse of execobj[].rsvd2
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>

The default context is always supported (as it contains the global
hangcheck stats) and the contexts for hangcheck are not limited
to any ring.

This was dropped in 2013 because it was supposed to have been included
with Ben's full-ppgtt patch set. It never landed and the bug remains.

References: https://bugs.freedesktop.org/show_bug.cgi?id=65845
Link: http://patchwork.freedesktop.org/patch/msgid/1372175222-27622-1-git-send-email-mika.kuoppala@intel.comSigned-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170616132849.29597-1-chris@chris-wilson.co.uk

For ease of use (i.e. avoiding a few checks and function calls), store
the object's cache coherency next to the cache is dirty bit.

Specifically this patch aims to reduce the frequency of no-op calls to
i915_gem_object_clflush() to counter-act the increase of such calls for
GPU only objects in the previous patch.

v2: Replace cache_dirty & ~cache_coherent with cache_dirty &&
!cache_coherent as gcc generates much better code for the latter
(Tvrtko)
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Dongwon Kim <dongwon.kim@intel.com>
Cc: Matt Roper <matthew.d.roper@intel.com>
Tested-by: Dongwon Kim <dongwon.kim@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170616105455.16977-1-chris@chris-wilson.co.ukReviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

Currently, we only mark the CPU cache as dirty if we skip a clflush.
This leads to some confusion where we have to ask if the object is in
the write domain or missed a clflush. If we always mark the cache as
dirty, this becomes a much simply question to answer.

The goal remains to do as few clflushes as required and to do them as
late as possible, in the hope of deferring the work to a kthread and not
block the caller (e.g. execbuf, flips).

v2: Always call clflush before GPU execution when the cache_dirty flag
is set. This may cause some extra work on llc systems that migrate dirty
buffers back and forth - but we do try to limit that by only setting
cache_dirty at the end of the gpu sequence.

v3: Always mark the cache as dirty upon a level change, as we need to
invalidate any stale cachelines due to external writes.
Reported-by: Dongwon Kim <dongwon.kim@intel.com>
Fixes: a6a7cc4b ("drm/i915: Always flush the dirty CPU cache when pinning the scanout")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Dongwon Kim <dongwon.kim@intel.com>
Cc: Matt Roper <matthew.d.roper@intel.com>
Tested-by: Dongwon Kim <dongwon.kim@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170615123850.26843-1-chris@chris-wilson.co.ukReviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

i915_vma_destroy() is now not used outside of i915_vma.c so we can
remove the export and make the function static.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170616123508.12673-1-chris@chris-wilson.co.ukReviewed-by: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>

Attach the tv_format property to the SDVO connector instead of passing
a '0' in place of the pointer to the property. This got broken when
the SDVO connector properties were converted to atomic.

We can thank sparse for catching this:
drivers/gpu/drm/i915/intel_sdvo.c:2742:75: warning: Using plain integer as NULL pointer

Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Fixes: 630d30a4 ("drm/i915: Convert intel_sdvo connector properties to atomic.")
Link: http://patchwork.freedesktop.org/patch/msgid/20170615172308.10121-1-ville.syrjala@linux.intel.comReviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>

gvt-next-2017-06-08

First gvt-next pull for 4.13:
- optimization for per-VM mmio save/restore (Changbin)
- optimization for mmio hash table (Changbin)
- scheduler optimization with event (Ping)
- vGPU reset refinement (Fred)
- other misc refactor and cleanups, etc.
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170608093547.bjgs436e3iokrzdm@zhen-hp.sh.intel.com

This reverts commit bb9d85f6.

New ddb allocation algorithm is a show stopper on my SKL system.

Besides not be able to get external DP 4k@60 (through USB type C),
It fully hang my screen when unplugging the USB type C.

Bugzilla: https://patchwork.freedesktop.org/patch/161571/
Fixes: bb9d85f6 ("drm/i915/skl: New ddb allocation algorithm")
Cc: Mahesh Kumar <mahesh1.kumar@intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1497376350-3400-1-git-send-email-rodrigo.vivi@intel.com

As per BSEPC, if device ready bit is '0' in enable IO sequence
then its a cold boot/reset scenario eg: S3/S4 resume. If cold boot
scenario detected in enable IO, then prepare port immediately.
In normal boot scenario, prepare port after glk_dsi_device_ready().
Without cold boot sequence enabled, features like S3/S4 doesn't work.
Signed-off-by: Madhav Chauhan <madhav.chauhan@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1497340095-5877-2-git-send-email-madhav.chauhan@intel.com

This patch divides glk_dsi_device_ready() function into
two part. First part will program LP wake and MIPI DSI mode
to MIPI_CTRL reg using newly defined function glk_dsi_enable_io().
glk_dsi_enable_io() will be called from intel_dsi_pre_enable.
Second part will do remaining device ready activities using
the existing function glk_dsi_device_ready().
Signed-off-by: Madhav Chauhan <madhav.chauhan@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1497340095-5877-1-git-send-email-madhav.chauhan@intel.com

Maarten and Ville noticed that we are enabling backlight via DP aux very
early in the modeset_init path via the intel_dp_aux_setup_backlight()
function, since commit e7156c83 ("drm/i915: Add Backlight Control using
DPCD for eDP connectors (v9)"). Looks like all we need to do during
_setup_backlight() is read the current brightness state instead of
modifying it.

v2: Rewrote commit message.

Cc: Ville Syrjala <ville.syrjala@linux.intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Yetunde Adebisi <yetundex.adebisi@intel.com>
Signed-off-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Tested-by: Puthikorn Voravootivat <puthik@chromium.org>
Fixes: e7156c83 ("drm/i915: Add Backlight Control using DPCD for eDP connectors (v9)")
Link: http://patchwork.freedesktop.org/patch/msgid/1497384239-2965-1-git-send-email-dhinakaran.pandiyan@intel.comSigned-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>

The function cnl_ddi_dp_set_dpll_hw_state does not need to be in global
scope, so make it static.

Cleans up sparse warning:
"symbol 'cnl_ddi_dp_set_dpll_hw_state' was not declared. Should it
 be static?"
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170613134751.29196-1-colin.king@canonical.comReviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>

With 830 the only thing needing pipe quirks, we can just drop the quirk
defines and replace the checks with IS_I830() checks.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170601143619.27840-8-ville.syrjala@linux.intel.comAcked-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>

The pipe A force quirk shouldn't needed except on 830. So let's nuke it
for the IBM Thinkpad T60 945 machines. This quirk pre-dates
KMS so it's usefulness is doubtful at best now.

The original bug report [1] describes the symptoms as "system hang on
closing T60 panel lid", and we already dropped a similar quirk for
another 945 machine in
commit 736a69ca ("drm/i915: Drop PIPE-A quirk for 945GSE HP Mini")
so I'm hopeful we can drop this one as well.

The quirk was added into xf86-video-intel in
commit 08903abe4dc0 ("Add pipe a force enable quirk for Lenovo T60")

[1] https://bugs.freedesktop.org/show_bug.cgi?id=16494Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170601143619.27840-7-ville.syrjala@linux.intel.comAcked-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>

The pipe A force quirk shouldn't needed except on 830. So let's nuke it
for the Toshiba Protege R-205/S-209 945 machines. This quirk pre-dates
KMS so it's usefulness is doubtful at best now.

Unfortunately the original bug report [1] isn't very helpful since it
doesn't describe the symptoms. And the commit message in xf86-video-intel
commit ecdb5963ef68 ("Add pipe A force enable quirk for Toshiba Portege R205-S209")
is not much help either.

However, if we assume the problem was the typical "closing the lid
hangs the box" type of thing, we already nuked the quirk for another
945 machine in
commit 736a69ca ("drm/i915: Drop PIPE-A quirk for 945GSE HP Mini")
and so I hope we can drop this one as well.

[1] https://bugs.freedesktop.org/show_bug.cgi?id=14944Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170601143619.27840-6-ville.syrjala@linux.intel.comAcked-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>

830 more or less requires both pipes and DPLLs to remain on as long
as either pipe is needed. However, when neither pipe is actually needed,
we can save a bit of power by turning everything off. To do that we add
a new "power well" that turns both pipes and DPLLs on and off in the
right order. Seems to save ~50mW on my Fujitsu-Siemens Lifebook S6010.

This also avoids having to abuse the load detection to force pipe A on
at init time. That was never very robust, and it only worked for one
pipe, whereas 830 really needs both pipes enabled. As a bonus the 830
pipe quirk is now a bit more isolated from the rest of the mode setting
infrastructure, which should mean that it's much less likely someone
will accidentally break it in the future. The extra cost is of course
slight code duplication, but that seems like a worthwile tradeoff here.

v2; s/BIT/BIT_ULL/
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170601143619.27840-5-ville.syrjala@linux.intel.comAcked-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>

The magic "enable the  DPLL three times" sequence feels like it
deserves a loop.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170601143619.27840-4-ville.syrjala@linux.intel.comReviewed-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>

If intel_crtc_disable_noatomic() were to ever get called during resume
we'd end up deadlocking since resume has its own acqcuire_ctx but
intel_crtc_disable_noatomic() still tries to use the
mode_config.acquire_ctx. Pass down the correct acquire ctx from the top.

Cc: stable@vger.kernel.org
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Fixes: e2c8b870 ("drm/i915: Use atomic helpers for suspend, v2.")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170601143619.27840-3-ville.syrjala@linux.intel.comReviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>

Pass down the correct acquire context to the pipe A quirk load detect
hack during display resume. Avoids deadlocking the entire thing.

Cc: stable@vger.kernel.org
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Fixes: e2c8b870 ("drm/i915: Use atomic helpers for suspend, v2.")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170601143619.27840-2-ville.syrjala@linux.intel.comReviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>

Currently the vma has one link member that is used for both holding its
place in the execbuf reservation list, and in any eviction list. This
dual property is quite tricky and error prone.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170615081435.17699-3-chris@chris-wilson.co.uk

This has the benefit of not requiring us to manipulate the
vma->exec_link list when tearing down the execbuffer, and is a
marginally cheaper test to detect the user error.
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/20170615081435.17699-2-chris@chris-wilson.co.uk

Combine the two slightly overlapping parameter structures we pass around
the execbuffer routines into one.
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/20170615081435.17699-1-chris@chris-wilson.co.uk

Add OA support for Geminilake (pretty much identical to Broxton), and
also add the associated OA configurations.
Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Link: http://patchwork.freedesktop.org/patch/msgid/20170613112309.4088-2-lionel.g.landwerlin@intel.com

Add OA support for Kabylake (pretty much identical to Skylake), and
also add the associated OA configurations.
Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>

Add macros to detect GT2/GT3 skus so we can apply the proper OA
configuration later.
Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>

In earlier iterations of the i915-perf driver we had a number of
callbacks/hooks from other parts of the i915 driver to e.g. notify us
when a legacy context was pinned and these could run asynchronously with
respect to the stream file operations and might also run in atomic
context.

dev_priv->perf.hook_lock had been for serialising access to state needed
within these callbacks, but as the code has evolved some of the hooks
have gone away or are implemented to avoid needing to lock any state.

The remaining use of this lock was actually redundant considering how
the gen7 oacontrol state used to be updated as part of a context pin
hook.
Signed-off-by: Robert Bragg <robert@sixbynine.org>
Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>

An oa_exponent_to_ns() utility and per-gen timebase constants where
recently removed when updating the tail pointer race condition WA, and
this restores those so we can update the _PROP_OA_EXPONENT validation
done in read_properties_unlocked() to not assume we have a 12.5MHz
timebase as we did for Haswell.

Accordingly the oa_sample_rate_hard_limit value that's referenced by
proc_dointvec_minmax defining the absolute limit for the OA sampling
frequency is now initialized to (timestamp_frequency / 2) instead of the
6.25MHz constant for Haswell.

v2:
    Specify frequency of 19.2MHz for BXT (Ville)
    Initialize oa_sample_rate_hard_limit per-gen too (Lionel)
Signed-off-by: Robert Bragg <robert@sixbynine.org>
Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>

These are auto generated from an XML description of metric sets,
currently maintained in gputop, ref:

 https://github.com/rib/gputop
 > gputop-data/oa-*.xml
 > scripts/i915-perf-kernelgen.py

 $ make -C gputop-data -f Makefile.xml
Signed-off-by: Robert Bragg <robert@sixbynine.org>
Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>

Enables access to OA unit metrics for BDW, CHV, SKL and BXT which all
share (more-or-less) the same OA unit design.

Of particular note in comparison to Haswell: some OA unit HW config
state has become per-context state and as a consequence it is somewhat
more complicated to manage synchronous state changes from the cpu while
there's no guarantee of what context (if any) is currently actively
running on the gpu.

The periodic sampling frequency which can be particularly useful for
system-wide analysis (as opposed to command stream synchronised
MI_REPORT_PERF_COUNT commands) is perhaps the most surprising state to
have become per-context save and restored (while the OABUFFER
destination is still a shared, system-wide resource).

This support for gen8+ takes care to consider a number of timing
challenges involved in synchronously updating per-context state
primarily by programming all config state from the cpu and updating all
current and saved contexts synchronously while the OA unit is still
disabled.

The driver intentionally avoids depending on command streamer
programming to update OA state considering the lack of synchronization
between the automatic loading of OACTXCONTROL state (that includes the
periodic sampling state and enable state) on context restore and the
parsing of any general purpose BB the driver can control. I.e. this
implementation is careful to avoid the possibility of a context restore
temporarily enabling any out-of-date periodic sampling state. In
addition to the risk of transiently-out-of-date state being loaded
automatically; there are also internal HW latencies involved in the
loading of MUX configurations which would be difficult to account for
from the command streamer (and we only want to enable the unit when once
the MUX configuration is complete).

Since the Gen8+ OA unit design no longer supports clock gating the unit
off for a single given context (which effectively stopped any progress
of counters while any other context was running) and instead supports
tagging OA reports with a context ID for filtering on the CPU, it means
we can no longer hide the system-wide progress of counters from a
non-privileged application only interested in metrics for its own
context. Although we could theoretically try and subtract the progress
of other contexts before forwarding reports via read() we aren't in a
position to filter reports captured via MI_REPORT_PERF_COUNT commands.
As a result, for Gen8+, we always require the
dev.i915.perf_stream_paranoid to be unset for any access to OA metrics
if not root.

v5: Drain submitted requests when enabling metric set to ensure no
    lite-restore erases the context image we just updated (Lionel)

v6: In addition to drain, switch to kernel context & update all
    context in place (Chris)

v7: Add missing mutex_unlock() if switching to kernel context fails
    (Matthew)

v8: Simplify OA period/flex-eu-counters programming by using the
    batchbuffer instead of modifying ctx-image (Lionel)

v9: Back to updating the context image (due to erroneous testing,
    batchbuffer programming the OA unit doesn't actually work)
    (Lionel)
    Pin context before updating context image (Chris)
    Drop MMIO programming now that we switch to a kernel context with
    right values in initial context image (Chris)

v10: Just pin_map the contexts we want to modify or let the
     configuration happen on first use (Chris)

v11: Update kernel context OA config through the batchbuffer rather
     than on the fly ctx-image update (Lionel)

v12: Rework OA context registers update again by swithing away from
     user contexts and reconfiguring the kernel context through the
     batchbuffer and updating all the other contexts' context image.
     Also take care to lock slice/subslice configuration when OA is
     on. (Lionel)

v13: Request rpcs updates on all engine when updating the OA config
     (Lionel)

v14: Drop any kind of rpcs management now that we monitor sseu
     configuration changes in a later patch (Lionel)
     Remove usleep after programming the NOA configs on Gen8+, this
     doesn't seem to be needed (Lionel)

v15: Respect coding style for block comments (Chris)

v16: Add missing i915_add_request() in case we fail to emit OA
     configuration (Matthew)
Signed-off-by: Robert Bragg <robert@sixbynine.org>
Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com> \o/
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>

Adds a static OA unit, MUX, B Counter + Flex EU configurations for basic
render metrics on Broadwell, Cherryview, Skylake and Broxton. These are
auto generated from an XML description of metric sets, currently
maintained in gputop, ref:

 https://github.com/rib/gputop
 > gputop-data/oa-*.xml
 > scripts/i915-perf-kernelgen.py

 $ make -C gputop-data -f Makefile.xml WHITELIST=RenderBasic

v2: add newlines to debug messages + fix comment (Matthew Auld)
Signed-off-by: Robert Bragg <robert@sixbynine.org>
Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>

Gen8+ might have mux configurations per slices/subslices. Depending on
whether slices/subslices have been fused off, only part of the
configuration needs to be applied. This change reworks the mux
configurations query mechanism to allow more than one set of registers
to be programmed.

v2: s/n_mux_regs/n_mux_configs/ (Matthew)
Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>

Assuming a uniform mask across all slices, this enables userspace to
determine the specific sub slices can be enabled. This information is
required, for example, to be able to analyse some OA counter reports
where the counter configuration depends on the HW sub slice
configuration.
Signed-off-by: Robert Bragg <robert@sixbynine.org>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>