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716 commits

Author SHA1 Message Date
Chris Wilson f9c513e9d6 drm/i915: Always call fence-lost prior to removing the fence
There is a minute window for a race between put-fence removing the fence
and for a new transaction by an external party on the GTT mmap. That is
we must zap the mmap prior to removing the fence and not afterwards.

Fixes regression from
commit 61050808bb
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date:   Tue Apr 17 15:31:31 2012 +0100

    drm/i915: Refactor put_fence() to use the common fence writing routine

v2: Remember the fence to remove with a local variable (gcc)

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-03-26 20:16:18 +01:00
Imre Deak 90797e6d1e drm/i915: create compact dma scatter lists for gem objects
So far we created a sparse dma scatter list for gem objects, where each
scatter list entry represented only a single page. In the future we'll
have to handle compact scatter lists too where each entry can consist of
multiple pages, for example for objects imported through PRIME.

The previous patches have already fixed up all other places where the
i915 driver _walked_ these lists. Here we have the corresponding fix to
_create_ compact lists. It's not a performance or memory footprint
improvement, but it helps to better exercise the new logic.

Reference: http://www.spinics.net/lists/dri-devel/msg33917.html
Signed-off-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-03-23 12:17:09 +01:00
Imre Deak 67d5a50c04 drm/i915: handle walking compact dma scatter lists
So far the assumption was that each dma scatter list entry contains only
a single page. This might not hold in the future, when we'll introduce
compact scatter lists, so prepare for this everywhere in the i915 code
where we walk such a list.

We'll fix the place _creating_ these lists separately in the next patch
to help the reviewing/bisectability.

Reference: http://www.spinics.net/lists/dri-devel/msg33917.html
Signed-off-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-03-23 12:16:36 +01:00
Daniel Vetter 0d4a42f6bd Linux 3.9-rc3
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Merge tag 'v3.9-rc3' into drm-intel-next-queued

Backmerge so that I can merge Imre Deak's coalesced sg entries fixes,
which depend upon the new for_each_sg_page introduce in

commit a321e91b6d
Author: Imre Deak <imre.deak@intel.com>
Date:   Wed Feb 27 17:02:56 2013 -0800

    lib/scatterlist: add simple page iterator

The merge itself is just two trivial conflicts:

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-03-19 09:47:30 +01:00
Jesse Barnes d62b4892f3 drm/i915: allow force wake at init time on VLV v2
We need to set the 'allow force wake' bit to enable forcewake handling
later on.

v2: split from clock gating patch (Jani)
    check for allowwakeack (Ville)

Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-03-19 09:38:32 +01:00
Ville Syrjälä 2bb4629add drm/i915: Add to_user_ptr()
to_user_ptr() simply casts a pointer passed as u64 from user space
to void __user * correctly. Using this lets us get rid of all the
tiresome casts.

The idea came from Chris Wilson <chris@chris-wilson.co.uk>.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-03-03 19:49:11 +01:00
Linus Torvalds d895cb1af1 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs pile (part one) from Al Viro:
 "Assorted stuff - cleaning namei.c up a bit, fixing ->d_name/->d_parent
  locking violations, etc.

  The most visible changes here are death of FS_REVAL_DOT (replaced with
  "has ->d_weak_revalidate()") and a new helper getting from struct file
  to inode.  Some bits of preparation to xattr method interface changes.

  Misc patches by various people sent this cycle *and* ocfs2 fixes from
  several cycles ago that should've been upstream right then.

  PS: the next vfs pile will be xattr stuff."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (46 commits)
  saner proc_get_inode() calling conventions
  proc: avoid extra pde_put() in proc_fill_super()
  fs: change return values from -EACCES to -EPERM
  fs/exec.c: make bprm_mm_init() static
  ocfs2/dlm: use GFP_ATOMIC inside a spin_lock
  ocfs2: fix possible use-after-free with AIO
  ocfs2: Fix oops in ocfs2_fast_symlink_readpage() code path
  get_empty_filp()/alloc_file() leave both ->f_pos and ->f_version zero
  target: writev() on single-element vector is pointless
  export kernel_write(), convert open-coded instances
  fs: encode_fh: return FILEID_INVALID if invalid fid_type
  kill f_vfsmnt
  vfs: kill FS_REVAL_DOT by adding a d_weak_revalidate dentry op
  nfsd: handle vfs_getattr errors in acl protocol
  switch vfs_getattr() to struct path
  default SET_PERSONALITY() in linux/elf.h
  ceph: prepopulate inodes only when request is aborted
  d_hash_and_lookup(): export, switch open-coded instances
  9p: switch v9fs_set_create_acl() to inode+fid, do it before d_instantiate()
  9p: split dropping the acls from v9fs_set_create_acl()
  ...
2013-02-26 20:16:07 -08:00
Al Viro 496ad9aa8e new helper: file_inode(file)
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-22 23:31:31 -05:00
Daniel Vetter eb32e4584d drm/i915: Use HAS_L3_GPU_CACHE in i915_gem_l3_remap
Yet another remnant ... this might explain why l3 remapping didn't
really work on HSW.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=57441
Spotted-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: stable@vger.kernel.org
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-02-20 00:21:47 +01:00
Imre Deak 769ce4643b drm/i915: don't clflush gem objects in stolen memory
As explained by Chris Wilson gem objects in stolen memory are always
coherent with the GPU so we don't need to ever flush the CPU caches for
these.

This fixes a breakage - at least with the compact sg patches applied -
during the resume/restore gtt mappings path, when we tried to clflush an
FB object in stolen memory, but since stolen objects don't have backing
pages we passed an invalid page pointer to drm_clflush_page().

Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-02-20 00:21:43 +01:00
Ben Widawsky 4fc7c971c3 drm/i915: Extract ring init from hw_init
The ring initialization will differ a bit in upcoming generations, and
this split will prepare the code for what's needed.

This patch also fixes a bug introduced in:
commit 9943393195
Author: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Date:   Tue Jan 22 14:12:17 2013 +0200

    drm/i915: use gem_set_seqno() on hardware init

After doing the extraction, the bad error handling became obvious.  I
acknowledge that this should be two patches, but it's a pretty
small/trivial patch. If requested, I can certainly do the fix as a
distinct patch.

v2: Should be cleanup blt, not init blt on failure (Chris)

v3: Forgot to git add on v2

Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-02-15 10:30:39 +01:00
Dave Airlie cd17ef4114 Merge tag 'drm-intel-next-2013-02-01' of git://people.freedesktop.org/~danvet/drm-intel into drm-next
Daniel writes:
"Probably the last feature pull for 3.9, there's some fixes outstanding
thought that I'd like to sneak in. And maybe 3.8 takes a bit longer ...
Anyway, highlights of this pull:
- Kill the horrible IS_DISPLAYREG hack to handle the mmio offset movements
  on vlv, big thanks to Ville.
- Dynamic power well support for Haswell, shaves away a bit when only
  using the eDP port on pipe A (Paulo). Plus unclaimed register fixes
  uncovered by this.
- Clarifications of the gpu hang/reset state transitions, hopefully fixing
  a few spurious -EIO deaths in userspace.
- Haswell ELD fixes.
- Some more (pp)gtt cleanups from Ben.
- A few smaller things all over.

Plus all the stuff from the previous rather small pull request:
- Broadcast RBG improvements and reduced color range fixes from Ville.
- Ben is on a "kill legacy gtt code for good" spree, first pile of patches
  included.
- No-relocs and bo lut improvements for faster execbuf from Chris.
- Some refactorings from Imre."

* tag 'drm-intel-next-2013-02-01' of git://people.freedesktop.org/~danvet/drm-intel: (101 commits)
  GPU/i915: Fix acpi_bus_get_device() check in drivers/gpu/drm/i915/intel_opregion.c
  drm/i915: Set the SR01 "screen off" bit in i915_redisable_vga() too
  drm/i915: Kill IS_DISPLAYREG()
  drm/i915: Introduce i915_vgacntrl_reg()
  drm/i915: gen6_gmch_remove can be static
  drm/i915: dynamic Haswell display power well support
  drm/i915: check the power down well on assert_pipe()
  drm/i915: don't send DP "idle" pattern before "normal" on HSW PORT_A
  drm/i915: don't run hsw power well code on !hsw
  drm/i915: kill cargo-culted locking from power well code
  drm/i915: Only run idle processing from i915_gem_retire_requests_worker
  drm/i915: Fix CAGF for HSW
  drm/i915: Reclaim GTT space for failed PPGTT
  drm/i915: remove intel_gtt structure
  drm/i915: Add probe and remove to the gtt ops
  drm/i915: extract hw ppgtt setup/cleanup code
  drm/i915: pte_encode is gen6+
  drm/i915: vfuncs for ppgtt
  drm/i915: vfuncs for gtt_clear_range/insert_entries
  drm/i915: Error state should print /sys/kernel/debug
  ...
2013-02-08 11:08:10 +10:00
Chris Wilson 725a5b5402 drm/i915: Only run idle processing from i915_gem_retire_requests_worker
When adding the fb idle detection to mark-inactive, it was forgotten
that userspace can drive the processing of retire-requests. We assumed
that it would be principally driven by the retire requests worker,
running once every second whilst active and so we would get the deferred
timer for free. Instead we spend too many CPU cycles reclocking the LVDS
preventing real work from being done.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reported-and-tested-by: Alexander Lam <lambchop468@gmail.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=58843
Cc: stable@vger.kernel.org
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-01-31 11:50:09 +01:00
Mika Kuoppala 9943393195 drm/i915: use gem_set_seqno() on hardware init
When machine was rebooted or module was reloaded,
gem_hw_init() set last_seqno to be identical to next_seqno.
This lead to situation that waits for first ever request
always passed immediately regardless if it was actually
executed.

Use gem_set_seqno() to be consistent how hw is
initialized on init, wrap and on resume.

Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-01-22 13:52:26 +01:00
Daniel Vetter f69061bedd drm/i915: create a race-free reset detection
With the previous patch the state transition handling of the reset
code itself is now (hopefully) race free and solid. But that still
leaves out everyone else - with the various lock-free wait paths
we have there's the possibility that the reset happens between the
point where we read the seqno we should wait on and the actual wait.

And if __wait_seqno then never sees the RESET_IN_PROGRESS state, we'll
happily wait for a seqno which will in all likelyhood never signal.

In practice this is not a big problem since the X server gets
constantly interrupted, and can then submit more work (hopefully) to
unblock everyone else: As soon as a new seqno write lands, all waiters
will unblock. But running the i-g-t reset testcase ZZ_hangman can
expose this race, especially on slower hw with fewer cpu cores.

Now looking forward to ARB_robustness and friends that's not the best
possible behaviour, hence this patch adds a reset_counter to be able
to detect any reset, even if a given thread never observed the
in-progress state.

The important part is to correctly order things:
- The write side needs to increment the counter after any seqno gets
  reset.  Hence we need to do that at the end of the reset work, and
  again wake everyone up. We also need to place a barrier in between
  any possible seqno changes and the counter increment, since any
  unlock operations only guarantee that nothing leaks out, but not
  that at later load operation gets moved ahead.
- On the read side we need to ensure that no reset can sneak in and
  invalidate the seqno. In all cases we can use the one-sided barrier
  that unlock operations guarantee (of the lock protecting the
  respective seqno/ring pair) to ensure correct ordering. Hence it is
  sufficient to place the atomic read before the mutex/spin_unlock and
  no additional barriers are required.

The end-result of all this is that we need to wake up everyone twice
in a reset operation:
- First, before the reset starts, to get any lockholders of the locks,
  so that the reset can proceed.
- Second, after the reset is completed, to allow waiters to properly
  and reliably detect the reset condition and bail out.

I admit that this entire reset_counter thing smells a bit like
overkill, but I think it's justified since it makes it really explicit
what the bail-out condition is. And we need a reset counter anyway to
implement ARB_robustness, and imo with finer-grained locking on the
horizont this is the most resilient scheme I could think of.

v2: Drop spurious change in the wait_for_error EXIT_COND - we only
need to wait until we leave the reset-in-progress wedged state.

v3: Don't play tricks with barriers in the throttle ioctl, the
spin_unlock is barrier enough.

I've also considered using a little helper to grab the current
reset_counter, but then decided that hiding the atomic_read isn't a
great idea, since having it explicitly show up in the code is a nice
remainder to reviews to check the memory barriers.

v4: Add a comment to explain why we need to fall through in
__wait_seqno in the end variable assignments.

v5: Review from Damien:
- s/smb/smp/ in a comment
- don't increment the reset counter after we've set it to WEDGED. Now
  we (again) properly wedge the gpu when the reset fails.

Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-01-21 19:53:54 +01:00
Dave Airlie 735dc0d1e2 Merge branch 'drm-kms-locking' of git://people.freedesktop.org/~danvet/drm-intel into drm-next
The aim of this locking rework is that ioctls which a compositor should be
might call for every frame (set_cursor, page_flip, addfb, rmfb and
getfb/create_handle) should not be able to block on kms background
activities like output detection. And since each EDID read takes about
25ms (in the best case), that always means we'll drop at least one frame.

The solution is to add per-crtc locking for these ioctls, and restrict
background activities to only use the global lock. Change-the-world type
of events (modeset, dpms, ...) need to grab all locks.

Two tricky parts arose in the conversion:
- A lot of current code assumes that a kms fb object can't disappear while
  holding the global lock, since the current code serializes fb
  destruction with it. Hence proper lifetime management using the already
  created refcounting for fbs need to be instantiated for all ioctls and
  interfaces/users.

- The rmfb ioctl removes the to-be-deleted fb from all active users. But
  unconditionally taking the global kms lock to do so introduces an
  unacceptable potential stall point. And obviously changing the userspace
  abi isn't on the table, either. Hence this conversion opportunistically
  checks whether the rmfb ioctl holds the very last reference, which
  guarantees that the fb isn't in active use on any crtc or plane (thanks
  to the conversion to the new lifetime rules using proper refcounting).
  Only if this is not the case will the code go through the slowpath and
  grab all modeset locks. Sane compositors will never hit this path and so
  avoid the stall, but userspace relying on these semantics will also not
  break.

All these cases are exercised by the newly added subtests for the i-g-t
kms_flip, tested on a machine where a full detect cycle takes around 100
ms.  It works, and no frames are dropped any more with these patches
applied.  kms_flip also contains a special case to exercise the
above-describe rmfb slowpath.

* 'drm-kms-locking' of git://people.freedesktop.org/~danvet/drm-intel: (335 commits)
  drm/fb_helper: check whether fbcon is bound
  drm/doc: updates for new framebuffer lifetime rules
  drm: don't hold crtc mutexes for connector ->detect callbacks
  drm: only grab the crtc lock for pageflips
  drm: optimize drm_framebuffer_remove
  drm/vmwgfx: add proper framebuffer refcounting
  drm/i915: dump refcount into framebuffer debugfs file
  drm: refcounting for crtc framebuffers
  drm: refcounting for sprite framebuffers
  drm: fb refcounting for dirtyfb_ioctl
  drm: don't take modeset locks in getfb ioctl
  drm: push modeset_lock_all into ->fb_create driver callbacks
  drm: nest modeset locks within fpriv->fbs_lock
  drm: reference framebuffers which are on the idr
  drm: revamp framebuffer cleanup interfaces
  drm: create drm_framebuffer_lookup
  drm: revamp locking around fb creation/destruction
  drm: only take the crtc lock for ->cursor_move
  drm: only take the crtc lock for ->cursor_set
  drm: add per-crtc locks
  ...
2013-01-21 07:44:58 +10:00
Chris Wilson 97c809fd9c drm/i915: Only apply the mb() when flushing the GTT domain during a finish
Now that we seem to have brought order to the GTT barriers, the last one
to review is the terminal barrier before we unbind the buffer from the
GTT. This needs to only be performed if the buffer still resides in the
GTT domain, and so we can skip some needless barriers otherwise.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-01-20 13:11:17 +01:00
Chris Wilson d0a57789d5 drm/i915: Only insert the mb() before updating the fence parameter
With a fence, we only need to insert a memory barrier around the actual
fence alteration for CPU accesses through the GTT. Performing the
barrier in flush-fence was inserting unnecessary and expensive barriers
for never fenced objects.

Note removing the barriers from flush-fence, which was effectively a
barrier before every direct access through the GTT, revealed that we
where missing a barrier before the first access through the GTT. Lack of
that barrier was sufficient to cause GPU hangs.

v2: Add a couple more comments to explain the new barriers

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-01-20 13:11:16 +01:00
Daniel Vetter 1f83fee08d drm/i915: clear up wedged transitions
We have two important transitions of the wedged state in the current
code:

- 0 -> 1: This means a hang has been detected, and signals to everyone
  that they please get of any locks, so that the reset work item can
  do its job.

- 1 -> 0: The reset handler has completed.

Now the last transition mixes up two states: "Reset completed and
successful" and "Reset failed". To distinguish these two we do some
tricks with the reset completion, but I simply could not convince
myself that this doesn't race under odd circumstances.

Hence split this up, and add a new terminal state indicating that the
hw is gone for good.

Also add explicit #defines for both states, update comments.

v2: Split out the reset handling bugfix for the throttle ioctl.

v3: s/tmp/wedged/ sugested by Chris Wilson. Also fixup up a rebase
error which prevented this patch from actually compiling.

v4: To unify the wedged state with the reset counter, keep the
reset-in-progress state just as a flag. The terminally-wedged state is
now denoted with a big number.

v5: Add a comment to the reset_counter special values explaining that
WEDGED & RESET_IN_PROGRESS needs to be true for the code to be
correct.

v6: Fixup logic errors introduced with the wedged+reset_counter
unification. Since WEDGED implies reset-in-progress (in a way we're
terminally stuck in the dead-but-reset-not-completed state), we need
ensure that we check for this everywhere. The specific bug was in
wait_for_error, which would simply have timed out.

v7: Extract an inline i915_reset_in_progress helper to make the code
more readable. Also annote the reset-in-progress case with an
unlikely, to help the compiler optimize the fastpath. Do the same for
the terminally wedged case with i915_terminally_wedged.

Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-01-20 13:11:16 +01:00
Daniel Vetter 308887aad1 drm/i915: fix reset handling in the throttle ioctl
While auditing the code I've noticed one place (the throttle ioctl)
which does not yet wait for the reset handler to complete and doesn't
properly decode the wedge state into -EAGAIN/-EIO. Fix this up by
calling the right helpers. This might explain the oddball "my
compositor just died in a successfull gpu reset" reports. Or maybe not, since
current mesa doesn't use this ioctl to throttle command submission.

The throttle ioctl doesn't take the struct_mutex, so to avoid busy-looping
with -EAGAIN while a reset is in process, check for errors first and wait
for the handler to complete if a reset is pending by calling
i915_gem_wait_for_error.

Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-01-20 13:11:15 +01:00
Daniel Vetter 33196dedda drm/i915: move wedged to the other gpu error handling stuff
And to make Ben Widawsky happier, use the gpu_error instead of
the entire device as the argument in some functions.

Drop the outdated comment on ->wedged for now, a follow-up patch will
change the semantics and add a proper comment again.

Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-01-20 13:11:15 +01:00
Daniel Vetter 99584db33b drm/i915: extract hangcheck/reset/error_state state into substruct
This has been sprinkled all over the place in dev_priv. I think
it'd be good to also move all the code into a separate file like
i915_gem_error.c, but that's for another patch.

Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-01-20 13:11:14 +01:00
Ben Widawsky 93d187993b drm/i915: Remove use of gtt_mappable_entries
Mappable_end, ie. size is almost always what you want as opposed to the
number of entries. Since we already have that information, we can scrap
the number of entries and only calculate it when needed.

If gtt_start is !0, this will have slightly different behavior. This
difference can only occur in DRI1, and exists when we try to kick out
the firmware fb. The new code seems like a bugfix to me.

The other case where we've changed the behavior is during init we check
the mappable region against our current known upper and lower limits
(64MB, and 512MB). This now matches the comment, and makes things more
convenient after removing gtt_mappable_entries.

Also worth noting is the setting of mappable_end is taken out of setup
because we do it earlier now in the DRI2 case and therefore need to add
that tiny hunk to support the DRI1 IOCTL.

v2: Move up mappable end to before legacy AGP init

v3: Add the dev_priv inclusion here from previous rebase error in patch
5

Reviewed-by: Rodrigo Vivi <rodrigo.vivi@gmail.com> (v2)
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
[danvet: squash in fix for a printk format flag mismatch warning.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-01-20 13:09:20 +01:00
Ben Widawsky 5d4545aef5 drm/i915: Create a gtt structure
The purpose of the gtt structure is to help isolate our gtt specific
properties from the rest of the code (in doing so it help us finish the
isolation from the AGP connection).

The following members are pulled out (and renamed):
gtt_start
gtt_total
gtt_mappable_end
gtt_mappable
gtt_base_addr
gsm

The gtt structure will serve as a nice place to put gen specific gtt
routines in upcoming patches. As far as what else I feel belongs in this
structure: it is meant to encapsulate the GTT's physical properties.
This is why I've not added fields which track various drm_mm properties,
or things like gtt_mtrr (which is itself a pretty transient field).

Reviewed-by: Rodrigo Vivi <rodrigo.vivi@gmail.com>
[Ben modified commit messages]
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-01-17 22:33:56 +01:00
Chris Wilson 43e28f092b drm/i915: Bail if we attempt to allocate pages for a purged object
Move the existing checking inside bind_to_gtt() to the more appropriate
layer in order to prevent recreation of the pages after they have been
explicitly truncated.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-01-17 22:07:59 +01:00
Chris Wilson dd624afd53 drm/i915: Add a debug interface to forcibly evict and shrink our object caches
As a means to investigate some bad system behaviour related to the
purging of the active, inactive and unbound lists, it is useful to be
able to manually control when those lists should be cleared.

v2: use _safe list iterators as we kick objects from the list as we
walk.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
[danvet: Add a small comment explaining why we don't need to check and
wait for gpu resets, acked by Chris on irc.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-01-17 22:07:57 +01:00
Imre Deak 0fa8779651 drm/i915: use gtt_get_size() instead of open coding it
Signed-off-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-01-17 22:07:56 +01:00
Imre Deak 56c844e539 drm/i915: merge {i965, sandybridge}_write_fence_reg()
The two functions are rather similar, so merge them.

Signed-off-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-01-17 22:07:55 +01:00
Imre Deak d865110cc2 drm/i915: merge get_gtt_alignment/get_unfenced_gtt_alignment()
The two functions are rather similar, so merge them.

Signed-off-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-01-17 22:07:54 +01:00
Dave Airlie b5cc6c0387 Merge tag 'drm-intel-next-2012-12-21' of git://people.freedesktop.org/~danvet/drm-intel into drm-next
Daniel writes:
- seqno wrap fixes and debug infrastructure from Mika Kuoppala and Chris
  Wilson
- some leftover kill-agp on gen6+ patches from Ben
- hotplug improvements from Damien
- clear fb when allocated from stolen, avoids dirt on the fbcon (Chris)
- Stolen mem support from Chris Wilson, one of the many steps to get to
  real fastboot support.
- Some DDI code cleanups from Paulo.
- Some refactorings around lvds and dp code.
- some random little bits&pieces

* tag 'drm-intel-next-2012-12-21' of git://people.freedesktop.org/~danvet/drm-intel: (93 commits)
  drm/i915: Return the real error code from intel_set_mode()
  drm/i915: Make GSM void
  drm/i915: Move GSM mapping into dev_priv
  drm/i915: Move even more gtt code to i915_gem_gtt
  drm/i915: Make next_seqno debugs entry to use i915_gem_set_seqno
  drm/i915: Introduce i915_gem_set_seqno()
  drm/i915: Always clear semaphore mboxes on seqno wrap
  drm/i915: Initialize hardware semaphore state on ring init
  drm/i915: Introduce ring set_seqno
  drm/i915: Missed conversion to gtt_pte_t
  drm/i915: Bug on unsupported swizzled platforms
  drm/i915: BUG() if fences are used on unsupported platform
  drm/i915: fixup overlay stolen memory leak
  drm/i915: clean up PIPECONF bpc #defines
  drm/i915: add intel_dp_set_signal_levels
  drm/i915: remove leftover display.update_wm assignment
  drm/i915: check for the PCH when setting pch_transcoder
  drm/i915: Clear the stolen fb before enabling
  drm/i915: Access to snooped system memory through the GTT is incoherent
  drm/i915: Remove stale comment about intel_dp_detect()
  ...

Conflicts:
	drivers/gpu/drm/i915/intel_display.c
2013-01-17 20:34:08 +10:00
Daniel Vetter 93927ca52a drm/i915: Revert shrinker changes from "Track unbound pages"
This partially reverts

commit 6c085a728c
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date:   Mon Aug 20 11:40:46 2012 +0200

    drm/i915: Track unbound pages

Closer inspection of that patch revealed a bunch of unrelated changes
in the shrinker:
- The shrinker count is now in pages instead of objects.
- For counting the shrinkable objects the old code only looked at the
  inactive list, the new code looks at all bounds objects (including
  pinned ones). That is obviously in addition to the new unbound list.
- The shrinker cound is no longer scaled with
  sysctl_vfs_cache_pressure. Note though that with the default tuning
  value of vfs_cache_pressue = 100 this doesn't affect the shrinker
  behaviour.
- When actually shrinking objects, the old code first dropped
  purgeable objects, then normal (inactive) objects. Only then did it,
  in a last-ditch effort idle the gpu and evict everything. The new
  code omits the intermediate step of evicting normal inactive
  objects.

Safe for the first change, which seems benign, and the shrinker count
scaling, which is a bit a different story, the endresult of all these
changes is that the shrinker is _much_ more likely to fall back to the
last-ditch resort of idling the gpu and evicting everything.  The old
code could only do that if something else evicted lots of objects
meanwhile (since without any other changes the nr_to_scan will be
smaller than the object count).

Reverting the vfs_cache_pressure behaviour itself is a bit bogus: Only
dentry/inode object caches should scale their shrinker counts with
vfs_cache_pressure. Originally I've had that change reverted, too. But
Chris Wilson insisted that it's too bogus and shouldn't again see the
light of day.

Hence revert all these other changes and restore the old shrinker
behaviour, with the minor adjustment that we now first scan the
unbound list, then the inactive list for each object category
(purgeable or normal).

A similar patch has been tested by a few people affected by the gen4/5
hangs which started to appear in 3.7, which some people bisected to
the "drm/i915: Track unbound pages" commit. But just disabling the
unbound logic alone didn't change things at all.

Note that this patch doesn't fix the referenced bugs, it only hides
the underlying bug(s) well enough to restore pre-3.7 behaviour. The
key to achieve that is to massively reduce the likelyhood of going
into a full gpu stall and evicting everything.

v2: Reword commit message a bit, taking Chris Wilson's comment into
account.

v3: On Chris Wilson's insistency, do not reinstate the rather bogus
vfs_cache_pressure change.

Tested-by: Greg KH <gregkh@linuxfoundation.org>
Tested-by: Dave Kleikamp <dave.kleikamp@oracle.com>
References: https://bugs.freedesktop.org/show_bug.cgi?id=55984
References: https://bugs.freedesktop.org/show_bug.cgi?id=57122
References: https://bugs.freedesktop.org/show_bug.cgi?id=56916
References: https://bugs.freedesktop.org/show_bug.cgi?id=57136
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: stable@vger.kernel.org
Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-01-10 18:02:44 +01:00
Chris Wilson 93be8788e6 drm/i915; Only increment the user-pin-count after successfully pinning the bo
As along the error path we do not correct the user pin-count for the
failure, we may end up with userspace believing that it has a pinned
object at offset 0 (when interrupted by a signal for example).

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-01-07 10:30:53 +01:00
Dave Airlie 8be0e5c427 Merge branch 'drm-intel-fixes' of git://people.freedesktop.org/~danvet/drm-intel into drm-next
Some fixes for 3.8:
- Watermark fixups from Chris Wilson (4 pieces).
- 2 snb workarounds, seem to be recently added to our internal DB.
- workaround for the infamous i830/i845 hang, seems now finally solid!
  Based on Chris' fix for SNA, now also for UXA/mesa&old SNA.
- Some more fixlets for shrinker-pulls-the-rug issues (Chris&me).
- Fix dma-buf flags when exporting (you).
- Disable the VGA plane if it's enabled on lid open - similar fix in
  spirit to the one I've sent you last weeek, BIOS' really like to mess
  with the display when closing the lid (awesome debug work from Krzysztof
  Mazur).

* 'drm-intel-fixes' of git://people.freedesktop.org/~danvet/drm-intel:
  drm/i915: disable shrinker lock stealing for create_mmap_offset
  drm/i915: optionally disable shrinker lock stealing
  drm/i915: fix flags in dma buf exporting
  i915: ensure that VGA plane is disabled
  drm/i915: Preallocate the drm_mm_node prior to manipulating the GTT drm_mm manager
  drm: Export routines for inserting preallocated nodes into the mm manager
  drm/i915: don't disable disconnected outputs
  drm/i915: Implement workaround for broken CS tlb on i830/845
  drm/i915: Implement WaSetupGtModeTdRowDispatch
  drm/i915: Implement WaDisableHiZPlanesWhenMSAAEnabled
  drm/i915: Prefer CRTC 'active' rather than 'enabled' during WM computations
  drm/i915: Clear self-refresh watermarks when disabled
  drm/i915: Double the cursor self-refresh latency on Valleyview
  drm/i915: Fixup cursor latency used for IVB lp3 watermarks
2012-12-30 13:54:12 +10:00
Ben Widawsky d7e5008f7c drm/i915: Move even more gtt code to i915_gem_gtt
This really should have been part of the kill agp series.

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-12-20 16:27:35 +01:00
Daniel Vetter da494d7ca5 drm/i915: disable shrinker lock stealing for create_mmap_offset
The mmap offset structure is not part of the drm/i915 code, but
provided by gem helpers. To avoid leaky abstractions (by either
depending upon implementation details of said helper wrt to
preallocations, or reimplementing it in our code and so fuzzing
around in internal details of that helpr) simply disable
the shrinker lock stealing accross calls into the helper functions.

This should fix igt/gem_tiled_swapping.

v2: Fix cleanup path confusion bemoaned by Chris Wilson.

Reported-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-12-20 14:57:35 +01:00
Daniel Vetter 677feac291 drm/i915: optionally disable shrinker lock stealing
commit 5774506f15
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date:   Wed Nov 21 13:04:04 2012 +0000

    drm/i915: Borrow our struct_mutex for the direct reclaim

added a nice trick to steal the struct_mutex lock in the shrinker if
it's the current task holding it. But this also caused the requirement
that every place which allocates memory needs to be careful about the
gem state of objects, since the shrinker could have pulled the rug out
from under it. We've usually solved this by carefully preallocating
things or ensure that buffers are pinned already.

But the shrinker also reaps mmap offset, so allocating those needs to
be careful, too. Now that code has been factored out into some common
helpers, so either we have fragile code depending upon the common
helper not doing something we don't want it to do. Or we need to
reimplement the mmap offset creation and so also leak implementation
details into our code.

Since this all results in leaky abstraction, cop out by disabling the
lock borrowing trick while calling down into the helpers. That way our
craziness is nicely confined to files in drm/i915.

v2: Split out the change to create_mmap_offset as request by Chris Wilson.

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-12-20 14:56:04 +01:00
Mika Kuoppala fca26bb453 drm/i915: Introduce i915_gem_set_seqno()
This function can be used to set the driver's next_seqno
to arbitrary value.

i915_gem_set_seqno() will idle the gpu, retire outstanding
requests, clear the semaphore mailboxes and set the hardware
status page's seqno index.

Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-12-19 11:25:10 +01:00
Mika Kuoppala ba1a7067c0 drm/i915: Always clear semaphore mboxes on seqno wrap
In preparation for setting the seqno to arbitrary value on init or
through debugfs. We need to always clear the semaphores and set the
hws page seqno index by calling intel_ring_init_seqno().

v2: rewrote the commit message as suggested by Chris Wilson.

Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-12-19 11:17:41 +01:00
Mika Kuoppala f7e98ad4d4 drm/i915: Initialize hardware semaphore state on ring init
Hardware status page needs to have proper seqno set
as our initial seqno can be arbitrary. If initial seqno is close
to wrap boundary on init and i915_seqno_passed() (31bit space)
refers to hw status page which contains zero, errorneous result
will be returned.

v2: clear mboxes and set hws page directly instead of going
through rings. Suggested by Chris Wilson.

v3: hws needs to be updated for all gens. Noticed by Chris
Wilson.

References: https://bugs.freedesktop.org/show_bug.cgi?id=58230
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-12-19 11:17:01 +01:00
Ben Widawsky 8782e26c0c drm/i915: Bug on unsupported swizzled platforms
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-12-18 22:31:23 +01:00
Ben Widawsky 7dbf9d6e0f drm/i915: BUG() if fences are used on unsupported platform
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-12-18 22:29:55 +01:00
Chris Wilson dc9dd7a20f drm/i915: Preallocate the drm_mm_node prior to manipulating the GTT drm_mm manager
As we may reap neighbouring objects in order to free up pages for
allocations, we need to be careful not to allocate in the middle of the
drm_mm manager. To accomplish this, we can simply allocate the
drm_mm_node up front and then use the combined search & insert
drm_mm routines, reducing our code footprint in the process.

Fixes (partially) i-g-t/gem_tiled_swapping

Reported-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
[danvet: Again fixup atomic bikeshed.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-12-18 22:02:29 +01:00
Linus Torvalds 3c2e81ef34 Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux
Pull DRM updates from Dave Airlie:
 "This is the one and only next pull for 3.8, we had a regression we
  found last week, so I was waiting for that to resolve itself, and I
  ended up with some Intel fixes on top as well.

  Highlights:
   - new driver: nvidia tegra 20/30/hdmi support
   - radeon: add support for previously unused DMA engines, more HDMI
     regs, eviction speeds ups and fixes
   - i915: HSW support enable, agp removal on GEN6, seqno wrapping
   - exynos: IPP subsystem support (image post proc), HDMI
   - nouveau: display class reworking, nv20->40 z compression
   - ttm: start of locking fixes, rcu usage for lookups,
   - core: documentation updates, docbook integration, monotonic clock
     usage, move from connector to object properties"

* 'drm-next' of git://people.freedesktop.org/~airlied/linux: (590 commits)
  drm/exynos: add gsc ipp driver
  drm/exynos: add rotator ipp driver
  drm/exynos: add fimc ipp driver
  drm/exynos: add iommu support for ipp
  drm/exynos: add ipp subsystem
  drm/exynos: support device tree for fimd
  radeon: fix regression with eviction since evict caching changes
  drm/radeon: add more pedantic checks in the CP DMA checker
  drm/radeon: bump version for CS ioctl support for async DMA
  drm/radeon: enable the async DMA rings in the CS ioctl
  drm/radeon: add VM CS parser support for async DMA on cayman/TN/SI
  drm/radeon/kms: add evergreen/cayman CS parser for async DMA (v2)
  drm/radeon/kms: add 6xx/7xx CS parser for async DMA (v2)
  drm/radeon: fix htile buffer size computation for command stream checker
  drm/radeon: fix fence locking in the pageflip callback
  drm/radeon: make indirect register access concurrency-safe
  drm/radeon: add W|RREG32_IDX for MM_INDEX|DATA based mmio accesss
  drm/exynos: support extended screen coordinate of fimd
  drm/exynos: fix x, y coordinates for right bottom pixel
  drm/exynos: fix fb offset calculation for plane
  ...
2012-12-17 08:26:17 -08:00
Chris Wilson eb119bd612 drm/i915: Access to snooped system memory through the GTT is incoherent
We ignore all the user requests to handle flushing to the GTT domain if
the user requests such on a snoopable bo, and as such access through the
GTT to such pages remains incoherent. The specs even warn that such
behaviour is undefined - a strong reason never to do so.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-12-17 12:28:23 +01:00
Mika Kuoppala 9e8e36879f drm/i915: Set initial seqno value close to wrap boundary
To gain confidence in the wrap handling, make it happen quite
soon after the boot.

Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-12-11 14:07:22 +01:00
Chris Wilson 107f27a5df drm/i915: Open-code i915_gpu_idle() for handling seqno wrapping
The complication is that during seqno wrapping we must be extremely
careful not to write to any ring as that will require a new seqno, and
so would recurse back into the seqno wrap handler. So we cannot call
i915_gpu_idle() as that does additional work beyond simply retiring the
current set of requests, and instead must do the minimal work ourselves
during seqno wrapping.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-12-11 14:07:03 +01:00
Mika Kuoppala f72b3435c1 drm/i915: Don't emit semaphore wait if wrap happened
If wrap just happened we need to prevent emitting waits for
pre wrap values. Detect this and emit no-ops instead.

v2: Use olr > seqno to detect wrap instead of *seqno == 0
as suggested by Chris Wilson.

v3: Use last used seqno to detect the wraparound. From
Chris Wilson

v4: Fixed unnecessary last_seqno assigment

References: https://bugs.freedesktop.org/show_bug.cgi?id=57967
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-12-11 13:32:26 +01:00
Linus Torvalds caf491916b Revert "revert "Revert "mm: remove __GFP_NO_KSWAPD""" and associated damage
This reverts commits a50915394f and
d7c3b937bd.

This is a revert of a revert of a revert.  In addition, it reverts the
even older i915 change to stop using the __GFP_NO_KSWAPD flag due to the
original commits in linux-next.

It turns out that the original patch really was bogus, and that the
original revert was the correct thing to do after all.  We thought we
had fixed the problem, and then reverted the revert, but the problem
really is fundamental: waking up kswapd simply isn't the right thing to
do, and direct reclaim sometimes simply _is_ the right thing to do.

When certain allocations fail, we simply should try some direct reclaim,
and if that fails, fail the allocation.  That's the right thing to do
for THP allocations, which can easily fail, and the GPU allocations want
to do that too.

So starting kswapd is sometimes simply wrong, and removing the flag that
said "don't start kswapd" was a mistake.  Let's hope we never revisit
this mistake again - and certainly not this many times ;)

Acked-by: Mel Gorman <mgorman@suse.de>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-10 11:03:05 -08:00
Chris Wilson e9b73c6739 drm/i915: Reduce memory pressure during shrinker by preallocating swizzle pages
On a machine with bit17 swizzling, we need to store the bit17 of the
physical page address in put-pages. This requires a memory allocation,
on average less than a page, which may be difficult to satisfy is the
request to put-pages is on behalf of the shrinker. We could allow that
allocation to pull from the reserved memory pools, but it seems much
safer to preallocate the array for tiled objects on affected machines.

v2: Export i915_gem_object_needs_bit17_swizzle() for reuse.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-12-07 01:16:15 +01:00
Mika Kuoppala 498d2ac15c drm/i915: Add intel_ring_handle_seqno wrap
If there are pre-wrap values in semaphore-mbox registers after wrap,
syncing against some after-wrap request will complete immediately.
Fix this by emitting ring commands to set mbox registers to zero
when the wrap happens.

v2: Use __intel_ring_begin to emit ring commands, from
Chris Wilson.

Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
[danvet: Add a small comment to handle_seqno_wrap.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-12-06 13:14:34 +01:00