Commit Graph

108 Commits

Author SHA1 Message Date
Chris Wilson 8d90dfd5ce drm/i915: Convert wait_for(I915_READ(reg)) to intel_wait_for_register()
By using the out-of-line intel_wait_for_register() not only do we can
efficiency from using the hybrid wait_for() contained within, but we
avoid code bloat from the numerous inlined loops, in total (all patches):

   text    data     bss     dec     hex filename
1078551    4557     416 1083524  108884 drivers/gpu/drm/i915/i915.ko
1070775    4557     416 1075748  106a24 drivers/gpu/drm/i915/i915.ko

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1467297225-21379-38-git-send-email-chris@chris-wilson.co.uk
2016-06-30 15:42:21 +01:00
Paulo Zanoni 80788a0fbb drm/i915/fbc: sanitize i915.enable_fbc during FBC init
The DDX driver changes its behavior depending on the value it reads
from i915.enable_fbc, so sanitize the value in order to allow it to
know what's going on. It uses this in order to choose the defaults for
the TearFree option. Before this patch, it would read -1 and always
assume that FBC was disabled, so it wouldn't force TearFree.

v2: Extract intel_sanitize_fbc_option() (Chris).
v3: Rebase.

Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1460574069-14005-1-git-send-email-paulo.r.zanoni@intel.com
2016-06-20 17:47:30 -03:00
Paulo Zanoni ab28a5474a drm/i915/fbc: update busy_bits even for GTT and flip flushes
We ignore ORIGIN_GTT because the hardware tracking can recognize GTT
writes and take care of them. We also ignore ORIGIN_FLIP because we
deal with flips without relying on the frontbuffer tracking
infrastructure. On the other hand, a flush is a flush and means we're
good to go, so we need to update busy_bits in order to reflect that,
even if we're not going to do anything else about it.

How to reproduce the bug fixed by this patch:
 - boot SKL up to the desktop environment
 - stop the display manager
 - run any of the igt/kms_frontbuffer_tracking/*fbc*onoff* subtests
 - the tests will fail

The steps above will create the right conditions for us to lose track
of busy_bits. If you, for example, run the full set of FBC tests, the
onoff subtests will succeed.

Also notice that the "bug" is that we'll just keep FBC disabled on
cases where it could be enabled, so it's not something the users can
perceive, it just affects power consumption numbers on properly
configured machines.

Testcase: igt/kms_frontbuffer_tracking/*fbc*onoff* (see above)
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1459804638-3588-2-git-send-email-paulo.r.zanoni@intel.com
2016-06-20 17:47:26 -03:00
Lyude c7f7e2feff drm/i915/fbc: Disable on HSW by default for now
>From https://bugs.freedesktop.org/show_bug.cgi?id=96461 :

This was kind of a difficult bug to track down. If you're using a
Haswell system running GNOME and you have fbc completely enabled and
working, playing videos can result in video artifacts. Steps to
reproduce:

- Run GNOME
- Ensure FBC is enabled and active
- Download a movie, I used the ogg version of Big Buck Bunny for this
- Run `gst-launch-1.0 filesrc location='some_movie.ogg' ! decodebin !
  glimagesink` in a terminal
- Watch for about over a minute, you'll see small horizontal lines go
  down the screen.

For the time being, disable FBC for Haswell by default.

Stefan Richter reported kernel freezes (no video artifacts) when fbc
is on.  (E3-1245 v3 with HD P4600; openbox and some KDE and LXDE
applications, thread begins at https://lkml.org/lkml/2016/4/26/813).
We also got reports from Steven Honeyman on openbox+roxterm.

v2 (From Paulo):
  - Add extra information to the commit message
  - Add Fixes tag
  - Rebase

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=96461
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=96464
Fixes: a98ee79317 ("drm/i915/fbc: enable FBC by default on HSW and BDW")
Cc: stable@vger.kernel.org
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Lyude <cpaul@redhat.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1465487895-7401-1-git-send-email-cpaul@redhat.com
2016-06-20 17:47:22 -03:00
Maarten Lankhorst faf68d9256 Reapply "drm/i915: Pass atomic states to fbc update, functions."
The patch was reverted as part of the original nonblocking commit
support, but is required for any kind of nonblocking commit.

This is required to let fbc updates run async. It has a lot of
checks whether certain locks are taken, which can be removed when
the relevant states are passed in as pointers.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1463490484-19540-17-git-send-email-maarten.lankhorst@linux.intel.com
Reviewed-by: Patrik Jakobsson <patrik.jakobsson@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/28208c38-8738-abdf-0cce-8d8f266b9c28@linux.intel.com
2016-06-16 14:28:35 +02:00
Daniel Vetter 2e7a5701c9 drm/doc: Appease sphinx
Mostly this is unexpected indents. But really it's just a
demonstration for my patch, all these issues have been found&fixed
using the correct source file and line number support I just added.
All line numbers have been perfectly accurate.

One issue looked a bit fishy in intel_lrc.c, where I don't quite grok
what sphinx is unhappy about. But since that file looks like it has
never seen a proper kernel-doc parser I figured better to fix in a
separate path.

v2: Use fancy new &drm_device->struct_mutex linking (Jani).

Cc: Jani Nikula <jani.nikula@intel.com>
Cc: linux-doc@vger.kernel.org
Cc: Jonathan Corbet <corbet@lwn.net>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
2016-06-02 16:25:20 +02:00
Daniel Vetter e42aeef123 drm/i915: Revert async unpin and nonblocking atomic commit
This reverts the following patches:

d55dbd06bb drm/i915: Allow nonblocking update of pageflips.
15c86bdb76 drm/i915: Check for unpin correctness.
95c2ccdc82 Reapply "drm/i915: Avoid stalling on pending flips for legacy cursor updates"
a6747b7304 drm/i915: Make unpin async.
03f476e1fc drm/i915: Prepare connectors for nonblocking checks.
2099deffef drm/i915: Pass atomic states to fbc update functions.
ee7171af72 drm/i915: Remove reset_counter from intel_crtc.
2ee004f7c5 drm/i915: Remove queue_flip pointer.
b8d2afae55 drm/i915: Remove use_mmio_flip kernel parameter.
8dd634d922 drm/i915: Remove cs based page flip support.
143f73b3bf drm/i915: Rework intel_crtc_page_flip to be almost atomic, v3.
84fc494b64 drm/i915: Add the exclusive fence to plane_state.
6885843ae1 drm/i915: Convert flip_work to a list.
aa420ddd8e drm/i915: Allow mmio updates on all platforms, v2.
afee4d8707 Revert "drm/i915: Avoid stalling on pending flips for legacy cursor updates"

"drm/i915: Allow nonblocking update of pageflips" should have been
split up, misses a proper commit message and seems to cause issues in
the legacy page_flip path as demonstrated by kms_flip.

"drm/i915: Make unpin async" doesn't handle the unthrottled cursor
updates correctly, leading to an apparent pin count leak. This is
caught by the WARN_ON in i915_gem_object_do_pin which screams if we
have more than DRM_I915_GEM_OBJECT_MAX_PIN_COUNT pins.

Unfortuantely we can't just revert these two because this patch series
came with a built-in bisect breakage in the form of temporarily
removing the unthrottled cursor update hack for legacy cursor ioctl.
Therefore there's no other option than to revert the entire pile :(

There's one tiny conflict in intel_drv.h due to other patches, nothing
serious.

Normally I'd wait a bit longer with doing a maintainer revert, but
since the minimal set of patches we need to revert (due to the bisect
breakage) is so big, time is running out fast. And very soon
(especially after a few attempts at fixing issues) it'll be really
hard to revert things cleanly.

Lessons learned:
- Not a good idea to rush the review (done by someone fairly new to
  the area) and not make sure domain experts had a chance to read it.

- Patches should be properly split up. I only looked at the two
  patches that should be reverted in detail, but both look like the
  mix up different things in one patch.

- Patches really should have proper commit messages. Especially when
  doing more than one thing, and especially when touching critical and
  tricky core code.

- Building a patch series and r-b stamping it when it has a built-in
  bisect breakage is not a good idea.

- I also think we need to stop building up technical debt by
  postponing atomic igt testcases even longer. I think it's clear that
  there's enough corner cases in this beast that we really need to
  have the testcases _before_ the next step lands.

(cherry picked from commit 5a21b6650a
from drm-intel-next-queeud)

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Patrik Jakobsson <patrik.jakobsson@linux.intel.com>
Cc: John Harrison <John.C.Harrison@Intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Acked-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Acked-by: Dave Airlie <airlied@redhat.com>
Acked-by: Jani Nikula <jani.nikula@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
2016-06-01 09:46:46 +02:00
Maarten Lankhorst 2099deffef drm/i915: Pass atomic states to fbc update functions.
This is required to let fbc updates run async. It has a lot of
checks whether certain locks are taken, which can be removed when
the relevant states are passed in as pointers.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1463490484-19540-17-git-send-email-maarten.lankhorst@linux.intel.com
Reviewed-by: Patrik Jakobsson <patrik.jakobsson@linux.intel.com>
2016-05-19 14:38:52 +02:00
Tvrtko Ursulin ac657f6461 drm/i915: Introduce IS_GEN macro
To be used for more efficient Gen range checking.

v2: Remove spurious chunk. (Chris Wilson)
v3: Rebase.
v4: Renamed from INTEL_GEN_RANGE and added GEN_FOREVER.

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> (v3)
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Dave Gordon <david.s.gordon@intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1462874228-6601-1-git-send-email-tvrtko.ursulin@linux.intel.com
2016-05-11 12:27:28 +01:00
Chris Wilson c033666a94 drm/i915: Store a i915 backpointer from engine, and use it
text	   data	    bss	    dec	    hex	filename
6309351	3578714	 696320	10584385	 a18141	vmlinux
6308391	3578714	 696320	10583425	 a17d81	vmlinux

Almost 1KiB of code reduction.

v2: More s/INTEL_INFO()->gen/INTEL_GEN()/ and IS_GENx() conversions

   text	   data	    bss	    dec	    hex	filename
6304579	3578778	 696320	10579677	 a16edd	vmlinux
6303427	3578778	 696320	10578525	 a16a5d	vmlinux

Now over 1KiB!

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1462545621-30125-3-git-send-email-chris@chris-wilson.co.uk
2016-05-09 13:41:24 +01:00
Joonas Lahtinen 72e96d6450 drm/i915: Refer to GGTT {,VM} consistently
Refer to the GGTT VM consistently as "ggtt->base" instead of just "ggtt",
"vm" or indirectly through other variables like "dev_priv->ggtt.base"
to avoid confusion with the i915_ggtt object itself and PPGTT VMs.

Refer to the GGTT as "ggtt" instead of indirectly through chaining.

As a bonus gets rid of the long-standing i915_obj_to_ggtt vs.
i915_gem_obj_to_ggtt conflict, due to removal of i915_obj_to_ggtt!

v2:
- Added some more after grepping sources with Chris

v3:
- Refer to GGTT VM through ggtt->base consistently instead of ggtt_vm
  (Chris)

v4:
- Convert all dev_priv->ggtt->foo accesses to ggtt->foo.

v5:
- Make patch checker happy

Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
2016-03-31 17:55:43 +03:00
Joonas Lahtinen 62106b4f6b drm/i915: Rename dev_priv->gtt to dev_priv->ggtt
Refer to Global GTT consistently as GGTT, thus rename dev_priv->gtt
to dev_priv->ggtt and struct i915_gtt to struct i915_ggtt.

Fix a couple of whitespace problems while at it.

v2:
- Fix a typo in commit message.

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
2016-03-18 15:18:15 +02:00
Paulo Zanoni a98ee79317 drm/i915/fbc: enable FBC by default on HSW and BDW
These platforms should be fine now.

FBC can allow very significant power savings for screen-on idle
systems, but it is worth mentioning that a lot of people won't get
significant power savings by enabling this feature because they may
have something else preventing the system from getting into the
deepest sleep states. Examples may include a hungry wifi device or a
max_performance SATA link power management policy. You can check your
PC state residencies on the powertop "Idle stats" tab. I recommend
trying to run "sudo powertop --auto-tune" and then seeing if the
residencies improve.

Oh, and in case you - the person reading this commit message - found
this commit through git bisect, please do the following:
 - Check your dmesg and see if there are error messages mentioning
   underruns around the time your problem started happening.
 - Download intel-gpu-tools, compile it, and run:
   $ sudo ./tests/kms_frontbuffer_tracking --run-subtest '*fbc-*' 2>&1 | tee fbc.txt
   Then send us the fbc.txt file, especially if you get a failure.
   This will really maximize your chances of getting the bug fixed
   quickly.
 - Try to find a reliable way to reproduce the problem, and tell us.
 - Boot with drm.debug=0xe, reproduce the problem, then send us the
   dmesg file.

v2: Don't enable by default on SKL.

Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1455655643-2535-1-git-send-email-paulo.r.zanoni@intel.com
2016-02-19 18:06:16 -02:00
Paulo Zanoni 5375ce9f38 drm/i915/fbc: set fbc->active from the new activation functions
Now that we have top-level gen-independent hw_activate and
hw_deactivate functions, set fbc->active directly from them, removing
the duplicated code.

Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1454101060-23198-3-git-send-email-paulo.r.zanoni@intel.com
2016-02-04 14:18:22 -02:00
Paulo Zanoni 8c40074cb2 drm/i915/fbc: unexport the HW level activation functions
The recent introduction of a new caller of dev_priv->fbc.deactivate()
is a good example of why we need unexport those functions. Anything
outside intel_fbc.c should only call the functions exported by
intel_fbc.c, so in order to enforce that, kill the function pointers
stored inside dev_priv->fbc and replace them with functions that can't
be called from outside intel_fbc.c.

This should make it much harder for new code to call these functions
from outside intel_fbc.c.

Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1454101060-23198-2-git-send-email-paulo.r.zanoni@intel.com
2016-02-04 14:17:45 -02:00
Paulo Zanoni e35be23f31 drm/i915/fbc: refactor some small functions called only once
The FBC fixes we've been doing in the last months required a lot of
refactor, so functions that were once big and called from different
spots are now small and called only once. IMHO now it's better to just
move the contents of these functions to their only callers since this
reduces the number of indirections while reading the code.

While at it, also improve the related comments a little bit.

Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1453210558-7875-26-git-send-email-paulo.r.zanoni@intel.com
2016-01-29 18:21:10 -02:00
Paulo Zanoni 9b42281f9d drm/i915/fbc: don't store/check a pointer to the FB
We already make sure we run intel_fbc_update_update during modesets
and page flips, and this function takes care of deactivating FBC, so
it shouldn't be possible for us to reach the condition we check at
intel_fbc_work_fn. So instead of grabbing framebuffer references and
adding a lot of code to track when we need to free them, just don't
track anything at all since we shouldn't need to.

v2: Rebase.

Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1453210558-7875-25-git-send-email-paulo.r.zanoni@intel.com
2016-01-29 18:20:39 -02:00
Paulo Zanoni b20d27526c drm/i915/fbc: don't store the fb_id on reg_params
We don't actually use fb_id anywhere. We already compare all
parameters that matter to the hardware: pixel format, stride,
fence_reg and ggtt_offset. The ID shouldn't make a difference.

Besides, we already update the FBC data at every modeset/flip, so this
can't change behind our backs.

Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1453210558-7875-23-git-send-email-paulo.r.zanoni@intel.com
2016-01-29 18:18:28 -02:00
Paulo Zanoni 913a3a6aca drm/i915/fbc: don't print no_fbc_reason to dmesg
Our dmesg messages started being misleading after we converted to the
enable+activate model: we always print "Disabling FBC", even when
we're just deactivating it. So, for example, when I boot my machine
and do "dmesg | grep -i fbc", I see:
  [drm:intel_fbc_enable] Enabling FBC on pipe A
  [drm:set_no_fbc_reason] Disabling FBC: framebuffer not tiled or fenced
but then, if I read the debugfs file, I will see:
  $ sudo cat i915_fbc_status
  FBC enabled
  Compressing: yes
so we can conclude that dmesg is misleading, since FBC is actually
enabled. What happened is that we deactivated FBC due to fbcon not
being tiled, but when we silently reactivated it when the display
manager started. We don't print activation messages since there may be
way too many of these operations per second during normal desktop
usage.

One possible solution would be to change set_no_fbc_reason to
correctly differentiate between disable and deactivation, but we
removed support from printing activation/deactivation messages in the
past because they were too frequent. So instead of doing this, let's
just not print anything on dmesg, and leave the debugfs file if the
user needs to investigate something. We already print when we enable
and disable FBC anyway on a given pipe, so this should already help
triaging bugs.

Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1453210558-7875-22-git-send-email-paulo.r.zanoni@intel.com
2016-01-29 18:18:16 -02:00
Paulo Zanoni 5bc40472de drm/i915/fbc: don't try to deactivate FBC if it's not enabled
During FBC invalidation, don't call intel_fbc_deactivate if it's not
enabled. This doesn't fix any bug, but helps making the interface
saner.

Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1453210558-7875-21-git-send-email-paulo.r.zanoni@intel.com
2016-01-29 18:17:56 -02:00
Paulo Zanoni 49227c4ae3 drm/i915/fbc: make FBC work with fastboot
Move intel_fbc_enable to a place where it is called regardless of the
"modeset" variable, and make sure intel_fbc_enable can be called
multiple times without intel_fbc_disable being called.

Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1453210558-7875-20-git-send-email-paulo.r.zanoni@intel.com
2016-01-29 18:17:36 -02:00
Paulo Zanoni 58f9c0bc55 drm/i915/fbc: move intel_fbc_{enable, disable} call one level up
Instead of duplicating the calls for every platform, let's just put
them in the correct places inside intel_atomic_commit. This will also
make it easier for us to move the enable call in order to support
fasbtoot.

Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1453210558-7875-19-git-send-email-paulo.r.zanoni@intel.com
2016-01-29 18:17:19 -02:00
Paulo Zanoni f51be2e0e3 drm/i915/fbc: choose the new FBC CRTC during atomic check
This opens the possibility of implementing nicer schemes to choose the
CRTC, such as checking the amount of stolen memory available, or
choosing the best pipe on platforms that don't die FBC to pipe or
plane A.

This code was written for another refactor that I ended up discarding,
so I don't actually need it, but I figured this patch would be an
improvement on its own so I kept it on the series.

Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1453210558-7875-18-git-send-email-paulo.r.zanoni@intel.com
2016-01-29 18:16:45 -02:00
Paulo Zanoni 010cf73d46 drm/i915/fbc: rewrite the multiple_pipes_ok() code for locking
Older FBC platforms have this restriction where FBC can't be enabled
if multiple pipes are enabled. In the current code, we disable FBC
before the second pipe becomes visible.

One of the problems with this code is that the current
multiple_pipes_ok() implementation just iterates through all CRTCs
looking at their states, but it doesn't make sure that the state
locks are grabbed. It also can't just grab the locks for every CRTC
since this would kill one of the biggest advantages of atomic
modesetting.

After the recent FBC changes, we now have the appropriate locks for
the given CRTC, so we can just try to maintain the state of each CRTC
and update it once intel_fbc_pre_update is called.

As a last note, I don't have gen 2/3 machines to test this code. My
current plan is to enable FBC on just the newer platforms, so this
patch is just an attempt to get the gen 2/3 code at least looking
sane, so if one day someone decide to fix FBC on these platforms, they
may have less work to do.

Not-tested-by: Paulo Zanoni <paulo.r.zanoni@intel.com> (only on HSW+)
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1453210558-7875-16-git-send-email-paulo.r.zanoni@intel.com
2016-01-29 18:15:56 -02:00
Paulo Zanoni 65c7600f07 drm/i915/fbc: make sure we cancel the work function at fbc_disable
Just to be sure nothing will survive a module unload. We need to do
this after the unlock in order to make sure the function won't get
stuck trying to grab the lock we already own while we wait for it to
finish.

Reported-by: Reported-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1453210558-7875-15-git-send-email-paulo.r.zanoni@intel.com
2016-01-29 18:15:43 -02:00
Paulo Zanoni c937ab3e58 drm/i915/fbc: rename the FBC disable functions
Instead of:
 - intel_fbc_disable_crtc(crtc)
 - intel_fbc_disable(dev_priv)
we now have:
 - intel_fbc_disable(crtc)
 - intel_fbc_global_disable(dev_priv)

This is because all the other functions that take a CRTC are called
 - intel_fbc_something(crtc)
Instead of:
 - intel_fbc_something_crtc(crtc)

And I also hope that the word "global" is going to help make it more
explicit that "global" is the unusual case, not the opposite.

Reported-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1453210558-7875-14-git-send-email-paulo.r.zanoni@intel.com
2016-01-29 18:13:33 -02:00
Paulo Zanoni 60eb2cc71c drm/i915/fbc: unexport intel_fbc_deactivate
With the addition and usage of intel_fbc_pre_update,
intel_fbc_deactivate is not used anymore outside intel_fbc.c, so kill
the exported function and rename __intel_fbc_deactivate.

Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1453210558-7875-13-git-send-email-paulo.r.zanoni@intel.com
2016-01-29 18:12:49 -02:00
Paulo Zanoni 1eb52238a5 drm/i915/fbc: fix the FBC state checking code
We'll now call intel_fbc_pre_update instead of intel_fbc_deactivate
during atomic commits. This will continue to guarantee that we
deactivate FBC and it will also update the state checking structures
at the correct time. Then, later, at the point where we were calling
intel_fbc_update, we'll only need to call intel_fbc_post_update.

Also add the proper warnings in case we don't have the appropriate
locks. Daniel mentioned the warnings will have to be removed for async
commits, but let's keep them here while we can.

Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1453210558-7875-12-git-send-email-paulo.r.zanoni@intel.com
2016-01-29 18:12:07 -02:00
Paulo Zanoni 212890cfcd drm/i915/fbc: split intel_fbc_update into pre and post update
So now pre_update will be responsible for unconditionally deactivating
FBC and updating the state cache, while post_update will be
responsible for checking if it can be enabled, then enabling it.

This is one more step into proper locking.

Notice that intel_fbc_flush now calls post_update directly. The FBC
flush can only happen for drawing operations - since we explicitly
ignore the flips -, so the FBC state is not expected to have changed
at this point. With this we can just run post_update, which will make
sure we won't deactivate+reactivate FBC as would be the case now if we
called pre_update + post_update.

Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1453210558-7875-11-git-send-email-paulo.r.zanoni@intel.com
2016-01-29 18:11:48 -02:00
Paulo Zanoni aaf78d276b drm/i915/fbc: introduce struct intel_fbc_state_cache
Per the new atomic locking rules, we need to cache the CRTC, plane and
FB state structures we use so we can access them later without needing
more locks. So do this.

Notice that there are some pieces of the FBC code that look at things
that are only computed during the modeset, so we can't just can't
precompute whether FBC can be activated during the update_state_cache
stage. We may be able to do this later.

Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1453210558-7875-10-git-send-email-paulo.r.zanoni@intel.com
2016-01-29 18:11:09 -02:00
Paulo Zanoni 261fe99ac2 drm/i915/fbc: don't flush for operations on the wrong frontbuffer
If frontbuffer_bits doesn't match the current frontbuffer, there's no
reason to recompress or update FBC.

There was a plan to make the FBC test suite catch this type of
problem, but it never got implemented due to being low priority.

While at it, also implement Ville's suggestion and use
plane->frontbuffer_bit instead of INTEL_FRONTBUFFER_PRIMARY.

Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1453210558-7875-8-git-send-email-paulo.r.zanoni@intel.com
2016-01-29 18:10:38 -02:00
Paulo Zanoni 0dd81544c9 drm/i915/fbc: don't use the frontbuffer tracking subsystem for flips
Before this patch, page flips would call intel_frontbuffer_flip() and
intel_frontbuffer_flip_complete(), which would call intel_fbc_flush(),
which would call intel_fbc_update(). The problem is that drawing
operations also trigger intel_fbc_flush() calls, so it's not
guaranteed that we have the CRTC and FB locks grabbed when
intel_fbc_flush() happens, since the call trace may come from the
rendering path.

We're trying to make the FBC code grab the appropriate CRTC/FB locks,
so split the drawing and the flipping logic in order to achieve that
in later patches. So now the frontbuffer tracking code is just going
to be used for frontbuffer drawing, and intel_fbc_update() is going to
be used directly for actual page flips.

As a note, we don't need to call intel_fbc_flip() during the two
places where we call intel_frontbuffer_flip() since in one of them we
already have an intel_fbc_update() call, and in the other we have the
planes disabled.

Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1453210558-7875-7-git-send-email-paulo.r.zanoni@intel.com
2016-01-29 18:10:20 -02:00
Paulo Zanoni ab34a7e8b5 drm/i915/fbc: replace frequent dev_priv->fbc.x with fbc->x
We say "dev_priv->fbc.something" way too many times in our code while
we could be saying just "fbc->something" with a previous declaration
of fbc. This has been bothering me for a while but I didn't want to
patch it since I wanted to fix the real problems first. But as I add
more code I keep thinking about it, especially since it makes the code
easier to read and it can make us fit 80 columns easier, so let's just
do the change now.

While at it, also rename from i915_fbc to intel_fbc because the whole
FBC code uses intel_fbc.

v2: Rebase after the work_fn changes.

Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1453406763-10400-1-git-send-email-paulo.r.zanoni@intel.com
2016-01-29 18:09:37 -02:00
Paulo Zanoni b183b3f143 drm/i915/fbc: introduce struct intel_fbc_reg_params
The early return inside __intel_fbc_update does not completely check
all the parameters that affect the FBC register values. For example,
we currently lack looking at crtc->adjusted_y (for the fence Y offset)
and all the parameters that affect the CFB size (for i8xx).

Instead of just adding the missing parameters to the check and hoping
that any changes to the fbc_activate functions also come with a
matching change to the __intel_fbc_update check, introduce a new
structure where we store these parameters and use the structure at the
fbc_activate function. Of course, it's still possible to access
everything from dev_priv in those functions, but IMHO the new code
will be harder to break.

v2: Rebase.

Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1453210558-7875-5-git-send-email-paulo.r.zanoni@intel.com
2016-01-29 18:08:38 -02:00
Paulo Zanoni 44a8a25708 drm/i915/fbc: extract intel_fbc_can_enable()
Make our enable/activate checking model more explicit, especially
since we now have intel_fbc_can_activate().

Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1453210558-7875-4-git-send-email-paulo.r.zanoni@intel.com
2016-01-29 18:08:25 -02:00
Paulo Zanoni 615b40d7e4 drm/i915/fbc: extract intel_fbc_can_activate()
Extract all the code that checks if the FBC configuration is valid to
its own function, making __intel_fbc_update() much simpler.

Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1453210558-7875-3-git-send-email-paulo.r.zanoni@intel.com
2016-01-29 18:07:38 -02:00
Paulo Zanoni ca18d51d77 drm/i915/fbc: wait for a vblank instead of 50ms when enabling
Instead of waiting for 50ms, just wait until the next vblank, since
it's the minimum requirement. The whole infrastructure of FBC is based
on vblanks, so waiting for X vblanks instead of X milliseconds sounds
like the correct way to go. Besides, 50ms may be less than a vblank on
super slow modes that may or may not exist.

There are some small improvements in PC state residency (due to the
fact that we're now using 16ms for the common modes instead of 50ms),
but the biggest advantage is still the correctness of being
vblank-based instead of time-based.

v2:
  - Rebase after changing the patch order.
  - Update the commit message.
v3:
  - Fix bogus vblank_get() instead of vblank_count() (Ville).
  - Don't forget to call drm_crtc_vblank_{get,put} (Chris, Ville)
  - Adjust the performance details on the commit message.
v4:
  - Don't grab the FBC mutex just to grab the vblank (Maarten)

Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1453406585-10233-1-git-send-email-paulo.r.zanoni@intel.com
2016-01-29 18:07:08 -02:00
Paulo Zanoni ee7d6cfa4b drm/i915: only recompress FBC after flushing a drawing operation
There's no need to stop and restart FBC, which is quite expensive as
we have to revalidate the CRTC state. After flushing a drawing
operation we know the CRTC state hasn't changed, so a nuke
(recompress) should be fine.

v2: Make it simpler (Chris).
v3: Rewrite the patch again due to patch order changes.
v4: Rewrite commit message (Chris).

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/
2015-12-03 11:38:11 -02:00
Paulo Zanoni 820bcabbf0 drm/i915: get rid of FBC {,de}activation messages
When running Cinnamon I see way too many pairs of these messages: many
per second. Get rid of them as they're just telling us FBC is working
as expected. We already have the messages for enable/disable, so we
don't really need messages for activation/deactivation.

v2: Rebase after changing the patch order.

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/
2015-12-03 11:37:28 -02:00
Paulo Zanoni 559d913583 drm/i915: kill fbc.uncompressed_size
Directly call intel_fbc_calculate_cfb_size() in the only place that
actually needs it, and use the proper check before removing the stolen
node. IMHO, this change makes our code easier to understand.

v2: Use drm_mm_node_allocated() (Chris).

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/
2015-12-03 11:36:42 -02:00
Paulo Zanoni 128d735606 drm/i915: use a single intel_fbc_work struct
This was already on my TODO list, and was requested both by Chris and
Ville, for different reasons. The advantages are avoiding a frequent
malloc/free pair, and the locality of having the work structure
embedded in dev_priv. The maximum used memory is also smaller since
previously we could have multiple allocated intel_fbc_work structs at
the same time, and now we'll always have a single one - the one
embedded on dev_priv. Of course, we're now using a little more memory
on the cases where there's nothing scheduled.

The biggest challenge here is to keep everything synchronized the way
it was before.

Currently, when we try to activate FBC, we allocate a new
intel_fbc_work structure. Then later when we conclude we must delay
the FBC activation a little more, we allocate a new intel_fbc_work
struct, and then adjust dev_priv->fbc.fbc_work to point to the new
struct. So when the old work runs - at intel_fbc_work_fn() - it will
check that dev_priv->fbc.fbc_work points to something else, so it does
nothing. Everything is also protected by fbc.lock.

Just cancelling the old delayed work doesn't work because we might
just cancel it after the work function already started to run, but
while it is still waiting to grab fbc.lock. That's why we use the
"dev_priv->fbc.fbc_work == work" check described in the paragraph
above.

So now that we have a single work struct we have to introduce a new
way to synchronize everything. So we're making the work function a
normal work instead of a delayed work, and it will be responsible for
sleeping the appropriate amount of time itself. This way, after it
wakes up it can grab the lock, ask "were we delayed or cancelled?" and
then go back to sleep, enable FBC or give up.

v2:
  - Spelling fixes.
  - Rebase after changing the patch order.
  - Fix ms/jiffies confusion.

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> (v1)
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/
2015-12-03 11:35:58 -02:00
Paulo Zanoni e6cd6dc104 drm/i915: check for FBC planes in the same place as the pipes
This moves the pre-gen4 check from update() to enable(). The HAS_DDI
in the original code is not needed since only gen 2/3 have the plane
swapping code.

v2: Rebase.
v3: Extract fbc_on_plane_a_only() (Chris).

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/
2015-12-03 11:35:34 -02:00
Paulo Zanoni c5ecd4691c drm/i915: alloc/free the FBC CFB during enable/disable
One of the problems with the current code is that it frees the CFB and
releases its drm_mm node as soon as we flip FBC's enable bit. This is
bad because after we disable FBC the hardware may still use the CFB
for the rest of the frame, so in theory we should only release the
drm_mm node one frame after we disable FBC. Otherwise, a stolen memory
allocation done right after an FBC disable may result in either
corrupted memory for the new owner of that memory region or corrupted
screen/underruns in case the new owner changes it while the hardware
is still reading it. This case is not exactly easy to reproduce since
we currently don't do a lot of stolen memory allocations, but I see
patches on the mailing list trying to expose stolen memory to user
space, so races will be possible.

I thought about three different approaches to solve this, and they all
have downsides.

The first approach would be to simply use multiple drm_mm nodes and
freeing the unused ones only after a frame has passed. The problem
with this approach is that since stolen memory is rather small,
there's a risk we just won't be able to allocate a new CFB from stolen
if the previous one was not freed yet. This could happen in case we
quickly disable FBC from pipe A and decide to enable it on pipe B, or
just if we change pipe A's fb stride while FBC is enabled.

The second approach would be similar to the first one, but maintaining
a single drm_mm node and keeping track of when it can be reused. This
would remove the disadvantage of not having enough space for two
nodes, but would create the new problem where we may not be able to
enable FBC at the point intel_fbc_update() is called, so we would have
to add more code to retry updating FBC after the time has passed. And
that can quickly get too complex since we can get invalidate, flush,
disable and other calls in the middle of the wait.

Both solutions above - and also the current code - have the problem
that we unnecessarily free+realloc FBC during invalidate+flush
operations even if the CFB size doesn't change.

The third option would be to move the allocation/deallocation to
enable/disable. This makes sure that the pipe is always disabled when
we allocate/deallocate the CFB, so there's no risk that the FBC
hardware may read or write to the memory right after it is freed from
drm_mm. The downside is that it is possible for user space to change
the buffer stride without triggering a disable/enable - only
deactivate/activate -, so we'll have to handle this case somehow - see
igt's kms_frontbuffer_tracking test, fbc-stridechange subtest. It
could be possible to implement a way to free+alloc the CFB during said
stride change, but it would involve a lot of book-keeping - exactly as
mentioned above - just for on case, so for now I'll keep it simple and
just deactivate FBC. Besides, we may not even need to disable FBC
since we do CFB over-allocation.

Note from Chris: "Starting a fullscreen client that covers a single
monitor in a multi-monitor setup will trigger a change in stride on
one of the CRTCs (the monitors will be flipped independently).". It
shouldn't be a huge problem if we lose FBC on multi-monitor setups
since these setups already have problems reaching deep PC states
anyway.

v2: Rebase after changing the patch order.
v3:
  - Remove references to the stride change case being "uncommon" and
    paste Chris' example.
  - Rebase after a change in a previous patch.

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/
2015-12-03 11:35:04 -02:00
Paulo Zanoni d029bcad6e drm/i915: introduce intel_fbc_{enable,disable}
The goal is to call FBC enable/disable only once per modeset, while
activate/deactivate/update will be called multiple times.

The enable() function will be responsible for deciding if a CRTC will
have FBC on it and then it will "lock" FBC on this CRTC: it won't be
possible to change FBC's CRTC until disable(). With this, all checks
and resource acquisition that only need to be done once per modeset
can be moved from update() to enable(). And then the update(),
activate() and deactivate() code will also get simpler since they
won't need to worry about the CRTC being changed.

The disable() function will do the reverse operation of enable(). One
of its features is that it should only be called while the pipe is
already off. This guarantees that FBC is stopped and nothing is
using the CFB.

With this, the activate() and deactivate() functions just start and
temporarily stop FBC. They are the ones touching the hardware enable
bit, so HW state reflects dev_priv->crtc.active.

The last function remaining is update(). A lot of times I thought
about renaming update() to activate() or try_to_activate() since it's
called when we want to activate FBC. The thing is that update() may
not only decide to activate FBC, but also deactivate or keep it on the
same state, so I'll leave this name for now.

Moving code to enable() and disable() will also help in case we decide
to move FBC to pipe_config or something else later.

The current patch only puts the very basic code on enable() and
disable(). The next commits will take care of moving more stuff from
update() to the new functions.

v2:
  - Rebase.
  - Improve commit message (Chris).
v3: Rebase after changing the patch order.
v4: Rebase again after upstream changes.

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/
2015-12-03 11:34:01 -02:00
Paulo Zanoni 0e631adc1a drm/i915: introduce is_active/activate/deactivate to the FBC terminology
The long term goal is to have enable/disable as the higher level
functions and activate/deactivate as the lower level functions, just
like we do for PSR and for the CRTC. This way, we'll run enable and
disable once per modeset, while update, activate and deactivate will
be run many times. With this, we can move the checks and code that
need to run only once per modeset to enable(), making the code simpler
and possibly a little faster.

This patch is just the first step on the conversion: it starts by
converting the current low level functions from enable/disable to
activate/deactivate. This patch by itself has no benefits other than
making review and rebase easier. Please see the next patches for more
details on the conversion.

v2:
  - Rebase.
  - Improve commit message (Chris).
v3: Rebase after changing the patch order.

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/
2015-12-03 11:33:01 -02:00
Paulo Zanoni 754d113304 drm/i915: pass the crtc as an argument to intel_fbc_update()
There's no need to reevaluate the status of every single crtc when a
single crtc changes its state.

With this, we're cutting the case where due to a change in pipe B,
intel_fbc_update() is called, then intel_fbc_find_crtc() concludes FBC
should be enabled on pipe A, then it completely rechecks the state of
pipe A only to conclude FBC should remain enabled on pipe A. If any
change on pipe A triggers a need to recompute whether FBC is valid on
pipe A, then at some point someone is going to call
intel_fbc_update(PIPE_A).

The addition of intel_fbc_deactivate() is necessary so we keep track
of the previously selected CRTC when we do invalidate/flush. We're
also going to continue the enable/disable/activate/deactivate concept
in the next patches.

v2: Rebase.
v3: Rebase after changing the patch order.

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/
2015-12-03 11:32:13 -02:00
Paulo Zanoni e9c5fd26ac drm/i915: set dev_priv->fbc.crtc before scheduling the enable work
This thing where we need to get the crtc either from the work
structure or the fbc structure itself is confusing and unnecessary.
Set fbc.crtc right when scheduling the enable work so we can always
use it.

The problem is not what gets passed and how to retrieve it. The
problem is that when we're in the other parts of the code we always
have to keep in mind that if FBC is already enabled we have to get the
CRTC from place A, if FBC is scheduled we have to get the CRTC from
place B, and if it's disabled there's no CRTC. Having a single place
to retrieve the CRTC from allows us to treat the "is enabled" and "is
scheduled" cases as the same case, reducing the mistake surface. I
guess I should add this to the commit message.

Besides the immediate advantages, this is also going to make one of
the next commits much simpler. And even later, when we introduce
enable/disable + activate/deactivate, this will be even simpler as
we'll set the CRTC at enable time. So all the
activate/deactivate/update code can just look at the single CRTC
variable regardless of the current state.

v2: Improve commit message (Chris).
v3: Rebase after changing the patch order.

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/
2015-12-03 11:14:05 -02:00
Paulo Zanoni 90d5234fdb drm/i915: fix the CFB size check
In function find_compression_threshold() we try to over-allocate CFB
space in order to reduce reallocations and fragmentation, and we're
not considering that at the CFB size check. Consider it.

There is also a longer-term plan to kill
dev_priv->fbc.uncompressed_size, but this will come later.

v2: Use drm_mm_node_allocated() (Chris).

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/
2015-12-03 11:13:45 -02:00
Paulo Zanoni 5205bbe62b drm/i915: remove in_dbg_master check from intel_fbc.c
From our maintainer Daniel Vetter a few days ago:
  "Oh dear this is dead code. kdbg uses the fbcon, which always uses
  untiled, which means fbc will never be enabled. Also we have 0 users
  and 0 test coverage for kdbg on top of i915 (Jesse implemented it
  for fun years back). Imo just remove all this code."

Adding to what Daniel said: for kgdboc's KMS support,
intel_pipe_set_base_atomic() already manually disables FBC, so we
won't do the in_dbg_master() check there. This is essentially a revert
of:

commit c924b934d0
Author: Jason Wessel <jason.wessel@windriver.com>
Date:   Thu Aug 5 09:22:32 2010 -0500
    i915: when kgdb is active display compression should be off

Besides, it is not clear what is the exact problem caused by FBC, and
why other features such as PSR, DRRS, IPS and RPM are not also
checking for in_dbg_master(). IMHO we should either remove the code as
suggested by Daniel or we add some nice comments explaining why is FBC
so special.

v2: Rebase due to new patch order.

Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Link: http://patchwork.freedesktop.org/patch/msgid/1446664257-32012-13-git-send-email-paulo.r.zanoni@intel.com
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
2015-11-10 11:00:58 +01:00
Paulo Zanoni 850bfaab71 drm/i915: clarify that checking the FB stride for CFB is intentional
Daniel was looking at this code and asked about whether fb->pitches[0]
is correct, then he suggested we should a comment to make sure it is
actually intentional.

For more information on the CFB size calculation, please see the
commit message of:

commit c4ffd40908
Author: Paulo Zanoni <paulo.r.zanoni@intel.com>
Date:   Thu Oct 1 19:55:57 2015 -0300
    drm/i915: fix CFB size calculation

Requested-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1446664257-32012-12-git-send-email-paulo.r.zanoni@intel.com
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
2015-11-10 11:00:34 +01:00