drm/i915/dp: Restore PPS HW state from the encoder resume hook

Similarly to the previous patch, initialize the PPS from the DP
encoder's resume hook. Note that as opposed to LVDS we can't do this
during encoder enabling, since we need the PPS for DP detection as well.
The PPS init code is now the same for init and resume, so factor out a
new intel_dp_pps_init() helper for this.

v2:
- Factor out intel_dp_pps_init() (Ville).

Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470827254-21954-4-git-send-email-imre.deak@intel.com

drm/i915/lvds: Restore initial HW state during encoder enabling

Atm the LVDS encoder depends on the PPS HW context being saved/restored
from generic suspend/resume code. Since the PPS is specific to the LVDS
and eDP encoders a cleaner way is to reinitialize it during encoder
enabling, so do this here for LVDS. Follow-up patches will init the PPS
for the eDP encoder similarly and remove the suspend/resume time save /
restore.

v2:
- Apply BSpec +1 offset and use DIV_ROUND_UP() when programming the
power cycle delay. (Ville)
v3: (Ville)
- Fix +1 vs. round-up order.
- s/reset_on_powerdown/powerdown_on_reset/

Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470827254-21954-3-git-send-email-imre.deak@intel.com

drm/i915: Merge TARGET_POWER_ON and PANEL_POWER_ON flag definitions

These two flags mean the same thing, so remove the duplication.

Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470827254-21954-2-git-send-email-imre.deak@intel.com

drm/i915: Merge the PPS register definitions

The PPS registers are pretty much the same everywhere, the differences
being:
- Register fields appearing, disappearing from one platform to the
  next: panel-reset-on-powerdown, backlight-on, panel-port,
  register-unlock
- Different register base addresses
- Different number of PPS instances: 2 on VLV/CHV/BXT, 1 everywhere
  else.

We can merge the separate set of PPS definitions by extending the PPS
instance argument to all platforms and using instance 0 on platforms
with a single instance. This means we'll need to calculate the register
addresses dynamically based on the given platform and PPS instance.

v2:
- Simplify if ladder in intel_pps_get_registers(). (Ville)

Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470827254-21954-1-git-send-email-imre.deak@intel.com

drm/i915/guc: re-optimise i915_guc_client layout

As we're tweaking the GuC-related code in debugfs, we can
drop the no-longer-used 'q_fail' and repack the structure.

Signed-off-by: Dave Gordon <david.s.gordon@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

drm/i915/guc: use for_each_engine_id() where appropriate

Now that host structures are indexed by host engine-id rather than
guc_id, we can usefully convert some for_each_engine() loops to use
for_each_engine_id() and avoid multiple dereferences of engine->id.

Also a few related tweaks to cache structure members locally wherever
they're used more than once or twice, hopefully eliminating memory
references.

Signed-off-by: Dave Gordon <david.s.gordon@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

drm/i915/guc: add engine mask to GuC client & pass to GuC

The Context Descriptor passed by the kernel to the GuC contains a field
specifying which engine(s) the context will use. Historically, this was
always set to "all of them", but if we had a separate client for each
engine, we could be more precise, and set only the bit for the engine
that the client was associated with. So this patch enables this usage,
in preparation for having multiple clients, though at this point there
is still only a single client used for all supported engines.

Signed-off-by: Dave Gordon <david.s.gordon@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

drm/i915/guc: refactor guc_init_doorbell_hw()

We have essentially the same code in each of two different
loops, so we can refactor it into a little helper function.

This also reduces the amount of work done during startup,
as we now only reprogram h/w found to be in a state other
than that expected, and so avoid the overhead of setting
doorbell registers to the state they're already in.

Signed-off-by: Dave Gordon <david.s.gordon@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

drm/i915/guc: doorbell reset should avoid used doorbells

guc_init_doorbell_hw() borrows the (currently single) GuC client to use
in reinitialising ALL the doorbell registers (as the hardware doesn't
reset them when the GuC is reset). As a prerequisite for accommodating
multiple clients, it should only reset doorbells that are supposed to be
disabled, avoiding those that are marked as in use by any client.

Signed-off-by: Dave Gordon <david.s.gordon@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

drm/i915: Use RCU to annotate and enforce protection for breadcrumb's bh

The bottom-half we use for processing the breadcrumb interrupt is a
task, which is an RCU protected struct. When accessing this struct, we
need to be holding the RCU read lock to prevent it disappearing beneath
us. We can use the RCU annotation to mark our irq_seqno_bh pointer as
being under RCU guard and then use the RCU accessors to both provide
correct ordering of access through the pointer.

Most notably, this fixes the access from hard irq context to use the RCU
read lock, which both Daniel and Tvrtko complained about.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1470761272-1245-3-git-send-email-chris@chris-wilson.co.uk

drm/i915: Move missed interrupt detection from hangcheck to breadcrumbs

In commit 2529d57050af ("drm/i915: Drop racy markup of missed-irqs from
idle-worker") the racy detection of missed interrupts was removed when
we went idle. This however opened up the issue that the stuck waiters
were not being reported, causing a test case failure. If we move the
stuck waiter detection out of hangcheck and into the breadcrumb
mechanims (i.e. the waiter) itself, we can avoid this issue entirely.
This leaves hangcheck looking for a stuck GPU (inspecting for request
advancement and HEAD motion), and breadcrumbs looking for a stuck
waiter - hopefully make both easier to understand by their segregation.

v2: Reduce the error message as we now run independently of hangcheck,
and the hanging batch used by igt also counts as a stuck waiter causing
extra warnings in dmesg.
v3: Move the breadcrumb's hangcheck kickstart to the first missed wait.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=97104
Fixes: 2529d57050af (waiter"drm/i915: Drop racy markup of missed-irqs...")
Testcase: igt/drv_missed_irq
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470761272-1245-2-git-send-email-chris@chris-wilson.co.uk

drm/i915: Always mark the writer as also a read for busy ioctl

One of the few guarantees we want the busy ioctl to provide is that the
reported busy writer is included in the set of busy read engines. This
should be provided by the ordering of setting and retiring the active
trackers, but we can do better by explicitly setting the busy read
engine flag for the last writer.

v2: More comments inside __busy_write_id() to explain why both fields
are set.

Fixes: 3fdc13c7a3cb ("drm/i915: Remove (struct_mutex) locking for busy-ioctl")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470762505-12799-1-git-send-email-chris@chris-wilson.co.uk
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drm: avoid "possible bad bitmask?" warning

Recent versions of gcc say this:

include/drm/i915_drm.h:96:34: warning: result of ‘65535 << 20’
requires 37 bits to represent, but ‘int’ only has 32 bits
[-Wshift-overflow=]

Reported-by: David Binderman <linuxdev.baldrick@gmail.com>
Signed-off-by: Dave Gordon <david.s.gordon@intel.com>
Cc: Dave Airlie <airlied@gmail.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1470764110-23855-1-git-send-email-david.s.gordon@intel.com

drm/i915: Correct typo for __i915_gem_active_get_rcu in a comment

I mistyped and added an extra _request_ to __i915_gem_active_get_rcu()
Also, the same happened to another comment for i915_gem_active_get_rcu()

Reported-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470758602-1338-1-git-send-email-chris@chris-wilson.co.uk

drm/i915: Use the g4x+ approach on gen2 for handling display stuff around GPU reset

We don't have GPU reset support for gen2, which means the display
hardware is unaffected when a GPU hang is handled. However as the ring
has in fact stopped, any flips still in the ring will never complete,
and thus the display base address updates will never happen. So we
really need to fix that up manually just like we do on g4x+.

In fact, let's just use intel_has_gpu_reset() instead of IS_GEN2()
since that'll also handle cases where someone would disable the GPU
reset support on gen3/4 for whatever reason.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470428910-12125-5-git-send-email-ville.syrjala@linux.intel.com
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drm/i915: Introduce gpu_reset_clobbers_display()

Factor out the "does the GPU reset clobber the display?" check into a
small helper.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470428910-12125-4-git-send-email-ville.syrjala@linux.intel.com
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drm/i915: Add a way to test the modeset done during gpu reset, v3.

Add force_reset_modeset_test as a parameter to force the modeset path during gpu reset.
This allows a IGT test to set the knob and trigger a hang to force the gpu reset,
even on platforms that wouldn't otherwise require it.

Changes since v1:
- Split out fix to separate commit.
Changes since v2:
- This commit is purely about force_reset_modeset_test now.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Testcase: drv_hangman.reset-with-forced-modeset
Tested-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470428910-12125-3-git-send-email-ville.syrjala@linux.intel.com
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>

drm/i915: Fix modeset handling during gpu reset, v5.

This function would call drm_modeset_lock_all, while the suspend/resume
functions already have their own locking. Fix this by factoring out
__intel_display_resume, and calling the atomic helpers for duplicating
atomic state and disabling all crtc's during suspend.

Changes since v1:
- Deal with -EDEADLK right after lock_all and clean up calls
  to hw readout.
- Always take all modeset locks so updates during gpu reset are blocked.
Changes since v2:
- Fix deadlock in intel_update_primary_planes.
- Move WARN_ON(EDEADLK) to __intel_display_resume.
- pctx -> ctx
- only call __intel_display_resume on success in intel_display_resume.
Changes since v3:
- Rebase on top of dev_priv -> dev change.
- Use drm_modeset_lock_all_ctx instead of drm_modeset_lock_all.
Changes since v4 [by vsyrjala]:
- Deal with skip_intermediate_wm
- Update comment w.r.t. mode_config.mutex vs. ->detect()
- Rebase due to INTEL_GEN() etc.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Fixes: e2c8b8701e2d ("drm/i915: Use atomic helpers for suspend, v2.")
Cc: stable@vger.kernel.org
Tested-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470428910-12125-2-git-send-email-ville.syrjala@linux.intel.com

drm/i915: Don't mark PCH underrun reporting as disabled for transcoder B/C on LPT-H

Marking PCH transcoder FIFO underrun reporting as disabled for
transcoder B/C on LPT-H will block us from enabling the south error
interrupt. So let's only mark transcoder A underrun reporting as
disabled initially.

This is a little tricky to hit since you need a machine with LPT-H, and
the BIOS must enable either pipe B or C at boot. Then i915 would mark
the "transcoder B/C" underrun reporting as disabled and never enable it
again, meaning south interrupts would never get enabled either. The only
other interrupt in there is actually the poison interrupt which, if we
could ever trigger it, would just result in a little error in dmesg.

Here's the resulting change in SDEIMR on my HSW when I boot it with
multiple displays attached:
- (0x000c4004): 0xf115ffff
+ (0x000c4004): 0xf114ffff

My previous attempt [1] tried to fix this a little differently, but
Daniel requested I do this instead.

[1] https://lists.freedesktop.org/archives/intel-gfx/2015-November/081420.html

Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470416417-15021-1-git-send-email-ville.syrjala@linux.intel.com
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drm/i915: Add some curly braces

intel_enable_pipe() looks rather confusing when one side doesn't have
the curly braces, and the other one does. And what's even worse,
there's another if-else inside the braceless side. Let's put braces
around it to make it clear which branch goes where.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470418894-1249-1-git-send-email-ville.syrjala@linux.intel.com
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>

drm/i915: Do not overwrite the request with zero on reallocation

When using RCU lookup for the request, commit 0eafec6d3244 ("drm/i915:
Enable lockless lookup of request tracking via RCU"), we acknowledge that
we may race with another thread that could have reallocated the request.
In order for the first thread not to blow up, the second thread must not
clear the request completed before overwriting it. In the RCU lookup, we
allow for the engine/seqno to be replaced but we do not allow for it to
be zeroed.

The choice we make is to either add extra checking to the RCU lookup, or
embrace the inherent races (as intended). It is more complicated as we
need to manually clear everything we depend upon being zero initialised,
but we benefit from not emiting the memset() to clear the entire
frequently allocated structure (that memset turns up in throughput
profiles). And at the same time, the lookup remains flexible for future
adjustments.

v2: Old style LRC requires another variable to be initialize. (The
danger inherent in not zeroing everything.)
v3: request->batch also needs to be cleared
v4: signaling.tsk is no long used unset, but pid still exists

Fixes: 0eafec6d3244 ("drm/i915: Enable lockless lookup of request...")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: "Goel, Akash" <akash.goel@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1470731014-6894-2-git-send-email-chris@chris-wilson.co.uk

drm/i915: Add smp_rmb() to busy ioctl's RCU dance

In the debate as to whether the second read of active->request is
ordered after the dependent reads of the first read of active->request,
just give in and throw a smp_rmb() in there so that ordering of loads is
assured.

v2: Explain the manual smp_rmb()

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1470731014-6894-1-git-send-email-chris@chris-wilson.co.uk

drm/i915: Don't check for idleness before retiring after a GPU hang

When we force the cleanup after a GPU hang, we want to retire all
requests, or else we may leak them if truly wedged (and the GPU never
advances again). Converting to the active request helpers had the issue
of doing the check against busyness before reporting the request, so if
we claim the GPU had hung but this engine hadn't we could potential skip
the request cleanup - triggering the self-check BUG.

Fixes: dcff85c8443e ("drm/i915: Enable i915_gem_wait_for_idle() ...")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1470728222-10243-3-git-send-email-chris@chris-wilson.co.uk

drm/i915: Wrap the protected active RCU dereference in a helper

As we do the lockdep protected RCU lookup in a couple of places,
refactor that code to a common helper i915_gem_active_raw().

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1470728222-10243-2-git-send-email-chris@chris-wilson.co.uk

drm/i915: Remove unused i915_gem_active_peek_rcu()

This was originally introduced to be used by the busy-ioctl, but in the
end busy ioctl performed a different dance. Since there are no users,
and no likely users, remove an unwanted chunk of the API.

Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1470728222-10243-1-git-send-email-chris@chris-wilson.co.uk
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drm/i915: Update DRIVER_DATE to 20160808

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

drm/i915: fix aliasing_ppgtt leak

In i915_ggtt_cleanup_hw we need to remember to free aliasing_ppgtt. This
fixes the following kmemleak message:

unreferenced object 0xffff880213cca000 (size 8192):
  comm "modprobe", pid 1298, jiffies 4294745402 (age 703.930s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<ffffffff817c808e>] kmemleak_alloc+0x4e/0xb0
    [<ffffffff8121f9c2>] kmem_cache_alloc_trace+0x142/0x1d0
    [<ffffffffa06d11ef>] i915_gem_init_ggtt+0x10f/0x210 [i915]
    [<ffffffffa06d71bb>] i915_gem_init+0x5b/0xd0 [i915]
    [<ffffffffa069749a>] i915_driver_load+0x97a/0x1460 [i915]
    [<ffffffffa06a26ef>] i915_pci_probe+0x4f/0x70 [i915]
    [<ffffffff81423015>] local_pci_probe+0x45/0xa0
    [<ffffffff81424463>] pci_device_probe+0x103/0x150
    [<ffffffff81515e6c>] driver_probe_device+0x22c/0x440
    [<ffffffff81516151>] __driver_attach+0xd1/0xf0
    [<ffffffff8151379c>] bus_for_each_dev+0x6c/0xc0
    [<ffffffff8151555e>] driver_attach+0x1e/0x20
    [<ffffffff81514fa3>] bus_add_driver+0x1c3/0x280
    [<ffffffff81516aa0>] driver_register+0x60/0xe0
    [<ffffffff8142297c>] __pci_register_driver+0x4c/0x50
    [<ffffffffa013605b>] 0xffffffffa013605b

Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Fixes: b18b6bde300e ("drm/i915/bdw: Free PPGTT struct")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1470420280-21417-1-git-send-email-matthew.auld@intel.com

drm/i915: Update comment before i915_spin_request

~jiffie and a few usecs is 3 orders of magnitude different. A bit
much. This was changed in

commit ca5b721e238226af1d767103ac852aeb8e4c0764
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date:   Fri Dec 11 11:32:58 2015 +0000

    drm/i915: Limit the busy wait on requests to 5us not 10ms!

But probably missed the comment since the change was non-local to the
comment.

v2: Polish comment more (Chris).

Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470413484-23775-1-git-send-email-daniel.vetter@ffwll.ch

drm/i915: Use drm official vblank_no_hw_counter callback.

No functional change. Instead of defining a new empty function
let's use what is available on drm.

It gets cleaner, and easy to read, and understand.

Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>

drm/i915: Fix copy_to_user usage for pipe_crc

Copy to user return the number of bytes it couldn't write
and zero on success. So any number different than 0 should
be considered a fault, not only when it doesn't write
the full size.

v2: fixed the inverted logic. (Ville)

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

Revert "drm/i915: Track active streams also for DP SST"

This reverts commit f64425a82bdb5c3d7e09ba765716da88a9b00eec.

active_streams will get totally out of whack with SST unless we
sync up with the hw state at readout, obviously! We don't yet
do that, so now the WARNs fire all the time. Let's revert :(

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470413142-26402-1-git-send-email-ville.syrjala@linux.intel.com
References: https://bugs.freedesktop.org/show_bug.cgi?id=95472#c14
Acked-by: Chris Wilson <chris@chris-wilson.co.uk>

drm/i915: fix WaInsertDummyPushConstPs

As pointed out by Chris Harris, we are using the wrong WA name, it
should in fact be WaToEnableHwFixForPushConstHWBug, also it should be
applied from C0 onwards for both BXT and KBL.

Fixes: 7b9005cd45f3 ("drm/i915: Add WaInsertDummyPushConstP for bxt and kbl")
Cc: Chris Harris <chris.harris@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Reported-by: Chris Harris <chris.harris@intel.com>
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Reviewed-by: Arun Siluvery <arun.siluvery@linux.intel.com>
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470127013-29653-1-git-send-email-matthew.auld@intel.com

drm/i915: Assert that the request hasn't been retired

With all callers now not playing tricks with dropping the struct_mutex
between waiting and retiring, we can assert that the request is ready to
be retired.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470388464-28458-19-git-send-email-chris@chris-wilson.co.uk

drm/i915: Repack fence tiling mode and stride into a single integer

In the previous commit, we moved the obj->tiling_mode out of a bitfield
and into its own integer so that we could safely use READ_ONCE(). Let us
now repair some of that damage by sharing the tiling_mode with its
companion, the fence stride.

v2: New magic

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470388464-28458-18-git-send-email-chris@chris-wilson.co.uk

drm/i915: Document and reject invalid tiling modes

Through the GTT interface to the fence registers, we can only handle
linear, X and Y tiling. The more esoteric tiling patterns are ignored.
Document that the tiling ABI only supports upto Y tiling, and reject any
attempts to set a tiling mode other than NONE, X or Y.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470388464-28458-17-git-send-email-chris@chris-wilson.co.uk

drm/i915: Remove locking for get_tiling

Since we are not concerned with userspace racing itself with set-tiling
(the order is indeterminant even if we take a lock), then we can safely
read back the single obj->tiling_mode and do the static lookup of
swizzle mode without having to take a lock.

get-tiling is reasonably frequent due to the back-channel passing around
of tiling parameters in DRI2/DRI3.

v2: Make tiling_mode a full unsigned int so that we can trivially use it
with READ_ONCE(). Separating it out into manual control over the flags
field was too noisy for a simple patch. Note that we could use the lower
bits of obj->stride for the tiling mode.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470388464-28458-16-git-send-email-chris@chris-wilson.co.uk

drm/i915: Remove pinned check from madvise ioctl

We don't need to incur the overhead of checking whether the object is
pinned prior to changing its madvise. If the object is pinned, the
madvise will not take effect until it is unpinned and so we cannot free
the pages being pointed at by hardware. Marking a pinned object with
allocated pages as DONTNEED will not trigger any undue warnings. The check
is therefore superfluous, and by removing it we can remove a linear walk
over all the vma the object has.

Still despite it being an overzealous check, that error code is part of
the current ABI and so we must proceed with caution.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470388464-28458-15-git-send-email-chris@chris-wilson.co.uk

drm/i915: Reduce locking inside swfinish ioctl

We only need to take the struct_mutex if the object is pinned to the
display engine and so requires checking for clflush. (The race with
userspace pinning the object to a framebuffer is irrelevant.)

v2: Use access once for compiler hints (or not as it is a bitfield)
v3: READ_ONCE, obj->pin_display is not a bitfield anymore
v4: Don't be creative with goto.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470388464-28458-14-git-send-email-chris@chris-wilson.co.uk

drm/i915: Remove (struct_mutex) locking for busy-ioctl

By applying the same logic as for wait-ioctl, we can query whether a
request has completed without holding struct_mutex. The biggest impact
system-wide is removing the flush_active and the contention that causes.

Testcase: igt/gem_busy
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Akash Goel <akash.goel@intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470388464-28458-13-git-send-email-chris@chris-wilson.co.uk

drm/i915: Remove (struct_mutex) locking for wait-ioctl

With a bit of care (and leniency) we can iterate over the object and
wait for previous rendering to complete with judicial use of atomic
reference counting. The ABI requires us to ensure that an active object
is eventually flushed (like the busy-ioctl) which is guaranteed by our
management of requests (i.e. everything that is submitted to hardware is
flushed in the same request). All we have to do is ensure that we can
detect when the requests are complete for reporting when the object is
idle (without triggering ETIME), locklessly - this is handled by
i915_gem_active_wait_unlocked().

The impact of this is actually quite small - the return to userspace
following the wait was already lockless and so we don't see much gain in
latency improvement upon completing the wait. What we do achieve here is
completing an already finished wait without hitting the struct_mutex,
our hold is quite short and so we are typically just a victim of
contention rather than a cause - but it is still one less contention
point!

v2: Break up a long line.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470388464-28458-12-git-send-email-chris@chris-wilson.co.uk

drm/i915: Do a nonblocking wait first in pread/pwrite

If we try and read or write to an active request, we first must wait
upon the GPU completing that request. Let's do that without holding the
mutex (and so allow someone else to access the GPU whilst we wait). Upon
completion, we will acquire the mutex and only then start the operation
(i.e. we do not rely on state from before the initial wait).

v2: Repaint the goto labels
v3: Move the tracepoints back to the start of the ioctls

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470388464-28458-11-git-send-email-chris@chris-wilson.co.uk

drm/i915: Remove unused no-shrinker-steal

After removing the user of this wart, we can remove the wart entirely.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470388464-28458-10-git-send-email-chris@chris-wilson.co.uk

drm/i915: Tidy generation of the GTT mmap offset

If we make the observation that mmap-offsets are only released when we
free an object, we can then deduce that the shrinker only creates free
space in the mmap arena indirectly by flushing the request list and
freeing expired objects. If we combine this with the lockless
vma-manager and lockless idling, we can avoid taking our big struct_mutex
until we need to actually free the requests.

One side-effect is that we defer the madvise checking until we need the
pages (i.e. the fault handler). This brings us into line with the other
delayed checks (and madvise in general).

v2: s/ret/err/ and use if (!err) rather than if (ret == 0)

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470388464-28458-9-git-send-email-chris@chris-wilson.co.uk

drm/i915/shrinker: Wait before acquiring struct_mutex under oom

We can now wait for the GPU (all engines) to become idle without
requiring the struct_mutex. Inside the shrinker, we need to currently
take the struct_mutex in order to purge objects and to purge the objects
we need the GPU to be idle - causing a stall whilst we hold the
struct_mutex. We can hide most of that stall by performing the wait
before taking the struct_mutex and only doing essential waits for
new rendering on objects to be freed.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470388464-28458-8-git-send-email-chris@chris-wilson.co.uk

drm/i915: Simplify do_idling() (Ironlake vt-d w/a)

Now that we pass along the expected interruptible nature for the
wait-for-idle, we do not need to modify the global
i915->mm.interruptible for this single call. (Only the immediate call to
i915_gem_wait_for_idle() takes the interruptible status as the other
action, dma_map_sg(), is independent of i915.ko)

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470388464-28458-7-git-send-email-chris@chris-wilson.co.uk

drm/i915: Enable i915_gem_wait_for_idle() without holding struct_mutex

The principal motivation for this was to try and eliminate the
struct_mutex from i915_gem_suspend - but we still need to hold the mutex
current for the i915_gem_context_lost(). (The issue there is that there
may be an indirect lockdep cycle between cpu_hotplug (i.e. suspend) and
struct_mutex via the stop_machine().) For the moment, enabling last
request tracking for the engine, allows us to do busyness checking and
waiting without requiring the struct_mutex - which is useful in its own
right.

As a side-effect of having a robust means for tracking engine busyness,
we can replace our other busyness heuristic, that of comparing against
the last submitted seqno. For paranoid reasons, we have a semi-ordered
check of that seqno inside the hangchecker, which we can now improve to
an ordered check of the engine's busyness (removing a locked xchg in the
process).

v2: Pass along "bool interruptible" as being unlocked we cannot rely on
i915->mm.interruptible being stable or even under our control.
v3: Replace check Ironlake i915_gpu_busy() with the common precalculated value

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470388464-28458-6-git-send-email-chris@chris-wilson.co.uk

drm/i915: Remove forced stop ring on suspend/unload

Before suspending (or unloading), we would first wait upon all rendering
to be completed and then disable the rings. This later step is a remanent
from DRI1 days when we did not use request tracking for all operations
upon the ring. Now that we are sure we are waiting upon the very last
operation by the engine, we can forgo clobbering the ring registers,
though we do keep the assert that the engine is indeed idle before
sleeping.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470388464-28458-5-git-send-email-chris@chris-wilson.co.uk

drm/i915/userptr: Remove superfluous interruptible=false on waiting

Inside the kthread context, we can't be interrupted by signals so
touching the mm.interruptible flag is pointless and wait-request now
consumes EIO itself.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470388464-28458-4-git-send-email-chris@chris-wilson.co.uk

drm/i915: Convert non-blocking userptr waits for requests over to using RCU

We can completely avoid taking the struct_mutex around the non-blocking
waits by switching over to the RCU request management (trading the mutex
for a RCU read lock and some complex atomic operations). The improvement
is that we gain further contention reduction, and overall the code
become simpler due to the reduced mutex dancing.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470388464-28458-3-git-send-email-chris@chris-wilson.co.uk

drm/i915: Convert non-blocking waits for requests over to using RCU

We can completely avoid taking the struct_mutex around the non-blocking
waits by switching over to the RCU request management (trading the mutex
for a RCU read lock and some complex atomic operations). The improvement
is that we gain further contention reduction, and overall the code
become simpler due to the reduced mutex dancing.

v2: Move i915_gem_fault tracepoint back to the start of the function,
before the unlocked wait.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470388464-28458-2-git-send-email-chris@chris-wilson.co.uk

drm/i915: Introduce i915_gem_active_wait_unlocked()

It is useful to be able to wait on pending rendering without grabbing
the struct_mutex. We can do this by using the i915_gem_active_get_rcu()
primitive to acquire a reference to the pending request without
requiring struct_mutex, just the RCU read lock, and then call
i915_wait_request().

v2: Rebase onto new i915_gem_active_get_unlocked() semantics that take
the RCU read lock on behalf of the caller.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470388464-28458-1-git-send-email-chris@chris-wilson.co.uk

Merge remote-tracking branch 'airlied/drm-next' into drm-intel-next-queued

Backmerge the 4.8 pull request state from Dave - conflicts were
getting out of hand, and Chris has some patches which outright don't
apply without everything merged together again.

Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>

drm/i915: Fix iboost setting for SKL Y/U DP DDI buffer translation entry 2

The spec was recently fixed to have the correct iboost setting for the
SKL Y/U DP DDI buffer translation table entry 2. Update our tables
to match.

Cc: David Weinehall <david.weinehall@linux.intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470140517-13011-1-git-send-email-ville.syrjala@linux.intel.com
Cc: stable@vger.kernel.org
Reviewed-by: David Weinehall <david.weinehall@linux.intel.com>

drm/i915/gen9: Give one extra block per line for SKL plane WM calculations

The bspec was updated a couple weeks ago to add an extra block per line
to plane watermark calculations for linear pixel formats.

Bspec update 115327 description:
  "Gen9+ - Updated the plane blocks per line calculation for linear
  cases. Adds +1 for all linear cases to handle the non-block aligned
  stride cases."

Cc: Lyude <cpaul@redhat.com>
Cc: drm-intel-fixes@lists.freedesktop.org
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470344880-27394-1-git-send-email-matthew.d.roper@intel.com
Reviewed-by: Lyude <cpaul@redhat.com>

drm/i915: Export our request as a dma-buf fence on the reservation object

If the GEM objects being rendered with in this request have been
exported via dma-buf to a third party, hook ourselves into the dma-buf
reservation object so that the third party can serialise with our
rendering via the dma-buf fences.

Testcase: igt/prime_busy
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1470324762-2545-26-git-send-email-chris@chris-wilson.co.uk

drm/i915: Enable lockless lookup of request tracking via RCU

If we enable RCU for the requests (providing a grace period where we can
inspect a "dead" request before it is freed), we can allow callers to
carefully perform lockless lookup of an active request.

However, by enabling deferred freeing of requests, we can potentially
hog a lot of memory when dealing with tens of thousands of requests per
second - with a quick insertion of a synchronize_rcu() inside our
shrinker callback, that issue disappears.

v2: Currently, it is our responsibility to handle reclaim i.e. to avoid
hogging memory with the delayed slab frees. At the moment, we wait for a
grace period in the shrinker, and block for all RCU callbacks on oom.
Suggested alternatives focus on flushing our RCU callback when we have a
certain number of outstanding request frees, and blocking on that flush
after a second high watermark. (So rather than wait for the system to
run out of memory, we stop issuing requests - both are nondeterministic.)

Paul E. McKenney wrote:

Another approach is synchronize_rcu() after some largish number of
requests.  The advantage of this approach is that it throttles the
production of callbacks at the source.  The corresponding disadvantage
is that it slows things up.

Another approach is to use call_rcu(), but if the previous call_rcu()
is still in flight, block waiting for it.  Yet another approach is
the get_state_synchronize_rcu() / cond_synchronize_rcu() pair.  The
idea is to do something like this:

        cond_synchronize_rcu(cookie);
        cookie = get_state_synchronize_rcu();

You would of course do an initial get_state_synchronize_rcu() to
get things going.  This would not block unless there was less than
one grace period's worth of time between invocations.  But this
assumes a busy system, where there is almost always a grace period
in flight.  But you can make that happen as follows:

        cond_synchronize_rcu(cookie);
        cookie = get_state_synchronize_rcu();
        call_rcu(&my_rcu_head, noop_function);

Note that you need additional code to make sure that the old callback
has completed before doing a new one.  Setting and clearing a flag
with appropriate memory ordering control suffices (e.g,. smp_load_acquire()
and smp_store_release()).

v3: More comments on compiler and processor order of operations within
the RCU lookup and discover we can use rcu_access_pointer() here instead.

v4: Wrap i915_gem_active_get_rcu() to take the rcu_read_lock itself.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: "Goel, Akash" <akash.goel@intel.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1470324762-2545-25-git-send-email-chris@chris-wilson.co.uk

drm/i915: Move i915_gem_object_wait_rendering()

Just move it earlier so that we can use the companion nonblocking
version in a couple of more callsites without having to add a forward
declaration.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470324762-2545-24-git-send-email-chris@chris-wilson.co.uk

drm/i915: Move obj->active:5 to obj->flags

We are motivated to avoid using a bitfield for obj->active for a couple
of reasons. Firstly, we wish to document our lockless read of obj->active
using READ_ONCE inside i915_gem_busy_ioctl() and that requires an
integral type (i.e. not a bitfield). Secondly, gcc produces abysmal code
when presented with a bitfield and that shows up high on the profiles of
request tracking (mainly due to excess memory traffic as it converts
the bitfield to a register and back and generates frequent AGI in the
process).

v2: BIT, break up a long line in compute the other engines, new paint
for i915_gem_object_is_active (now i915_gem_object_get_active).

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470324762-2545-23-git-send-email-chris@chris-wilson.co.uk

drm/i915: Use dev_priv consistently through the intel_frontbuffer interface

Rather than a mismash of struct drm_device *dev and struct
drm_i915_private *dev_priv being used freely within a function, be
consistent and only pass along dev_priv.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470324762-2545-22-git-send-email-chris@chris-wilson.co.uk

drm/i915: Use atomics to manipulate obj->frontbuffer_bits

The individual bits inside obj->frontbuffer_bits are protected by each
plane->mutex, but the whole bitfield may be accessed by multiple KMS
operations simultaneously and so the RMW need to be under atomics.
However, for updating the single field we do not need to mandate that it
be under the struct_mutex, one more step towards its removal as the de
facto BKL.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470324762-2545-21-git-send-email-chris@chris-wilson.co.uk

drm/i915: Make fb_tracking.lock a spinlock

We only need a very lightweight mechanism here as the locking is only
used for co-ordinating a bitfield.

v2: Move the cheap unlikely tests into the caller
v3: Move the kerneldoc into the header (now separated out into
intel_fronbuffer.h for better kerneldoc and readability)

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtien <joonas.lahtinen@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1470324762-2545-20-git-send-email-chris@chris-wilson.co.uk

drm/i915: Separate intel_frontbuffer into its own header

In view of adding inline functions into the intel_frontbuffer section,
we first split the header into its own file so that we can integrate it
more easily with kerneldoc.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1470324762-2545-19-git-send-email-chris@chris-wilson.co.uk

drm/i915: Remove highly confusing i915_gem_obj_ggtt_pin()

Since i915_gem_obj_ggtt_pin() is an idiom breaking curry function for
i915_gem_object_ggtt_pin(), spare us the confusion and remove it.
Removing it now simplifies later patches to change the i915_vma_pin()
(and friends) interface.

v2: Add a redundant GEM_BUG_ON(!view) to
i915_gem_obj_lookup_or_create_ggtt_vma()

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470324762-2545-18-git-send-email-chris@chris-wilson.co.uk

drm/i915: Make i915_vma_pin() small and inline

Not only is i915_vma_pin() called for every single object on every single
execbuf, it is usually a simple increment as the VMA is already bound for
execution by the GPU. Rearrange the tests for unbound and pin_count
overflow so that we can do the increment and test very cheaply and
compact enough to inline the operation into execbuf. The trick used is
to note that we can check for an overflow bit (keeping space available
for it inside the flags) at the same time as checking the binding bits.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470324762-2545-17-git-send-email-chris@chris-wilson.co.uk

drm/i915: Combine all i915_vma bitfields into a single set of flags

In preparation to perform some magic to speed up i915_vma_pin(), which
is among the hottest of hot paths in execbuf, refactor all the bitfields
accessed by i915_vma_pin() into a single unified set of flags.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470324762-2545-16-git-send-email-chris@chris-wilson.co.uk

drm/i915: Start passing around i915_vma from execbuffer

During execbuffer we look up the i915_vma in order to reserve them in
the VM. However, we then do a double lookup of the vma in order to then
pin them, all because we lack the necessary interfaces to operate on
i915_vma - so introduce i915_vma_pin()!

v2: Tidy parameter lists to remove one level of redirection in the hot
path.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470324762-2545-15-git-send-email-chris@chris-wilson.co.uk

drm/i915: Wrap vma->pin_count accessors with small inline helpers

In the next few patches, the VMA pinning API is overhauled and to reduce
the churn we pull out the update to the accessors into a prep patch.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470324762-2545-14-git-send-email-chris@chris-wilson.co.uk

drm/i915: Record allocated vma size

Tracking the size of the VMA as allocated allows us to dramatically
reduce the complexity of later functions (like inserting the VMA in to
the drm_mm range manager).

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470324762-2545-13-git-send-email-chris@chris-wilson.co.uk

drm/i915: Update i915_gem_get_ggtt_size/_alignment to use drm_i915_private

For consistency, internal functions should take drm_i915_private rather
than drm_device. Now that we are subclassing drm_device, there are no
more size wins, but being consistent is its own blessing.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470324762-2545-12-git-send-email-chris@chris-wilson.co.uk

drm/i915: Update the GGTT size/alignment query functions

In order to be consistent with other address space functions, we want to
pass around 64-bit sizes, even though all known global GTT are limited
to 4GiB. Similarly, we are trying to be consistent in using the _ggtt_
nomenclature when referring to the special global GTT.

v2: Update docs to consistently state "global GTT".

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470324762-2545-11-git-send-email-chris@chris-wilson.co.uk

drm/i915: Convert 4096 alignment request to 0 for drm_mm allocations

As we always allocate in chunks of 4096 (that being both the PAGE_SIZE
and our own GTT_PAGE_SIZE), we know that all results from the drm_mm are
aligned to at least 4096. The drm_mm allocator itself is optimised for
alignment == 0, and so by converting alignments of 4096 to 0 we can
satisfy our own requirements and still hit the faster path.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470324762-2545-10-git-send-email-chris@chris-wilson.co.uk

drm/i915: Split insertion/binding of an object into the VM

Split the insertion into the address space's range manager and binding
of that object into the GTT to simplify the code flow when pinning a
VMA.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470324762-2545-9-git-send-email-chris@chris-wilson.co.uk

drm/i915: Reduce WARN(i915_gem_valid_gtt_space) to a debug-only check

i915_gem_valid_gtt_space() is used after inserting the VMA to double
check the list - the location should have been chosen to pass all the
restrictions.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470324762-2545-8-git-send-email-chris@chris-wilson.co.uk

drm/i915: Pad GTT views of exec objects up to user specified size

Our GPUs impose certain requirements upon buffers that depend upon how
exactly they are used. Typically this is expressed as that they require
a larger surface than would be naively computed by pitch * height.
Normally such requirements are hidden away in the userspace driver, but
when we accept pointers from strangers and later impose extra conditions
on them, the original client allocator has no idea about the
monstrosities in the GPU and we require the userspace driver to inform
the kernel how many padding pages are required beyond the client
allocation.

v2: Long time, no see
v3: Try an anonymous union for uapi struct compatibility

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470324762-2545-7-git-send-email-chris@chris-wilson.co.uk

drm/i915: Fix up vma alignment to be u64

This is not the full fix, as we are required to percolate the u64 nature
down through the drm_mm stack, but this is required now to prevent
explosions due to mismatch between execbuf (eb_vma_misplaced) and vma
binding (i915_vma_misplaced) - and reduces the risk of spurious changes
as we adjust the vma interface in the next patches.

v2: long long casts not required for u64 printk (%llx)

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470324762-2545-6-git-send-email-chris@chris-wilson.co.uk

drm/i915: Remove i915_gem_execbuffer_retire_commands()

Move the single line to the callsite as the name is now misleading, and
the purpose is solely to add the request to the execution queue. Here,
we can see that if we failed to dispatch the batch from the request, we
can forgo flushing the GPU when closing the request.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470324762-2545-5-git-send-email-chris@chris-wilson.co.uk

drm/i915: Remove request retirement before each batch

This reimplements the denial-of-service protection against igt from
commit 227f782e4667 ("drm/i915: Retire requests before creating a new
one") and transfers the stall from before each batch into get_pages().
The issue is that the stall is increasing latency between batches which
is detrimental in some cases (especially coupled with execlists) to
keeping the GPU well fed. Also we have made the observation that retiring
requests can of itself free objects (and requests) and therefore makes
a good first step when shrinking.

v2: Recycle objects prior to i915_gem_object_get_pages()
v3: Remove the reference to the ring from i915_gem_requests_ring() as it
operates on an intel_engine_cs.
v4: Since commit 9b5f4e5ed6fd ("drm/i915: Retire oldest completed request
before allocating next") we no longer need the safeguard to retire
requests before get_pages(). We no longer see the huge latencies when
hitting the shrinker between allocations.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470324762-2545-4-git-send-email-chris@chris-wilson.co.uk

drm/i915: Double check the active status on the batch pool

We should not rely on obj->active being uptodate unless we manually
flush it. Instead, we can verify that the next available batch object is
idle by looking at its last active request (and checking it for
completion).

v2: remove the struct drm_device forward declaration added in the
process of removing its necessity

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470324762-2545-3-git-send-email-chris@chris-wilson.co.uk

drm/i915: Remove surplus drm_device parameter to i915_gem_evict_something()

Eviction is VM local, so we can ignore the significance of the
drm_device in the caller, and leave it to i915_gem_evict_something() to
manage itself.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470324762-2545-2-git-send-email-chris@chris-wilson.co.uk

drm/i915: Combine loops within i915_gem_evict_something

Slight micro-optimise to produce combine loops so that gcc is able to
optimise the inner-loops concisely. Since we are reviewing the loops, we
can update the comments to describe the current state of affairs, in
particular the distinction between evicting from the global GTT (which
may contain untracked items and transient global pins) and the
per-process GTT.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470324762-2545-1-git-send-email-chris@chris-wilson.co.uk

drm/i915: Acquire audio powerwell for HD-Audio registers

On Haswell/Broadwell, the HD-Audio block is inside the HDMI/display
power well and so the sna-hda audio codec acquires the display power
well while it is operational. However, Skylake separates the powerwells
again, but yet we still need the audio powerwell to setup the registers.
(But then the hardware uses those registers even while powered off???)

Acquiring the powerwell around setting the chicken bits when setting up
the audio channel does at least silence the WARNs from touching our
registers whilst unpowered. We silence our own test cases, but maybe
there is a latent bug in using the audio channel?

v2: Grab both rpm wakelock and audio wakelock

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=96214
Fixes: 03b135cebc47 "ALSA: hda - remove dependency on i915 power well for SKL")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Libin Yang <libin.yang@intel.com>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Marius Vlad <marius.c.vlad@intel.com>
Tested-by: Hans de Goede <hdegoede@redhat.com>
Cc: stable@vger.kernel.org
Link: http://patchwork.freedesktop.org/patch/msgid/1470240540-29004-1-git-send-email-chris@chris-wilson.co.uk
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drm/i915: Don't try to ack sink irqs when there are none

My ASUS PB278 at least doesn't seem to appreciate when you try to
ack sink irqs when there are none. Results in this sort of dmesg spam
[drm:drm_dp_dpcd_access] too many retries, giving up

Let's skip the ack if there are no pending irqs. I have no clue why we
do this in two places. One of them likely should just go away. Oh, and
MST has its own sink irq handler too...

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1469717448-4297-12-git-send-email-ville.syrjala@linux.intel.com
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drm/i915: Remove useless rate_to_index() usage

No need to iterate the rates array in intel_dp_max_link_rate(). We know
the max rate will be the last entry, and we already know the size.

Cc: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Cc: Jim Bride <jim.bride@linux.intel.com>
Cc: Manasi D Navare <manasi.d.navare@intel.com>
Cc: Durgadoss R <durgadoss.r@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1469717448-4297-10-git-send-email-ville.syrjala@linux.intel.com
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drm/i915: Allow MST sinks to work even if drm_probe_ddc() fails

With HSW + Dell UP2414Q (at least) drm_probe_ddc() occasionally fails,
and then we'll assume that the entire display has been disconnected.
We don't need the EDID from the main link, so we can simply check if
the sink is MST capable, and if so treat is as connected.

v2: Skip drm_probe_ddc() entirely for MST (Daniel)

Cc: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Cc: Jim Bride <jim.bride@linux.intel.com>
Cc: Manasi D Navare <manasi.d.navare@intel.com>
Cc: Durgadoss R <durgadoss.r@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1469800276-6979-1-git-send-email-ville.syrjala@linux.intel.com

drm/i915: Track active streams also for DP SST

s/active_mst_links/active_streams/ and use it also for SST. We can then
use this information in the hpd handling to see if the link is active
or not, and thus whether we may need to retrain.

Cc: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Cc: Jim Bride <jim.bride@linux.intel.com>
Cc: Manasi D Navare <manasi.d.navare@intel.com>
Cc: Durgadoss R <durgadoss.r@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1469717448-4297-6-git-send-email-ville.syrjala@linux.intel.com
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drm/i915: Reject mixing MST and SST/HDMI on the same digital port

We can't mix MST with SST/HDMI on the same physical port, so we'll need
to reject such configurations in check_digital_port_conflicts(). Nothing
else will prevent this as MST has its fake encoders and its own connectors
so the cloning checks won't catch this.

The same digital port can be used multiple times, but only if all the
encoders involved are MST encoders, so we only want to check MST vs.
SST/HDMI, not MST vs. MST. And SST/HDMI vs. SST/HDMI we already check.

Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1469717448-4297-5-git-send-email-ville.syrjala@linux.intel.com
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drm/i915: Avoid mixing up SST and MST in DDI setup

The MST vs. SST selection should depend purely on the choice of the
connector/encoder. So don't try to determine the correct DDI mode
based on the intel_dp->is_mst, which simply tells us whether the sink
is in MST mode or not. Instead derive the information from the encoder
type. Since the link training code deals in non-fake encoders, we'll
also need to keep a second copy of that information around, which we'll
now designate as 'link_mst'.

Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1469717448-4297-4-git-send-email-ville.syrjala@linux.intel.com
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drm/i915: Read PSR caps/intermediate freqs/etc. only once on eDP

Currently we re-read a bunch of static eDP panel caps from the DPCD
over and over again. Let's do it only once to save some time and effort.

v2: Make thing less confusing with intel_edp_init_dpcd() (Chris)
    Move no_aux_handshake setup in there as well
v3: Move tps3/rate printout to intel_dp_long_pulse() so that
    we'll still get them on eDP as well

Cc: 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> (v1)
Link: http://patchwork.freedesktop.org/patch/msgid/1469800359-7087-1-git-send-email-ville.syrjala@linux.intel.com

drm/i915: Add missing rpm wakelock to GGTT pread

Joonas spotted a discrepancy between the pwrite and pread ioctls, in
that pwrite takes the rpm wakelock around its GGTT access, The wakelock
is required in order for the GTT to function. In disregard for the
current convention, we take the rpm wakelock around the access itself
rather than around the struct_mutex as the nesting is not strictly
required and such ordering will one day be fixed by explicitly noting
the barrier dependencies between the GGTT and rpm.

Fixes: b50a53715f09 ("drm/i915: Support for pread/pwrite ...")
Reported-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Ankitprasad Sharma <ankitprasad.r.sharma@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: drm-intel-fixes@lists.freedesktop.org
Link: http://patchwork.freedesktop.org/patch/msgid/1470298193-21765-1-git-send-email-chris@chris-wilson.co.uk
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>

drm/i915/fbc: FBC causes display flicker when VT-d is enabled on Skylake

Erratum SKL075: Display Flicker May Occur When Both VT-d And FBC Are Enabled

"Display flickering may occur when both FBC (Frame Buffer Compression)
and VT - d (Intel® Virtualization Technology for Directed I/O) are enabled
and in use by the display controller."

Ville found the w/a name in the database:
WaFbcTurnOffFbcWhenHyperVisorIsUsed:skl,bxt and also dug out that it
affects Broxton.

v2: Log when the quirk is applied.
v3: Ensure i915.enable_fbc is false when !HAS_FBC()
v4: Fix function name after rebase
v5: Add Broxton to the workaround

Note for backporting to stable, we need to add
  #define mkwrite_device_info(ptr) \
((struct intel_device_info *)INTEL_INFO(ptr))

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: stable@vger.kernel.org
Link: http://patchwork.freedesktop.org/patch/msgid/1470296633-20388-1-git-send-email-chris@chris-wilson.co.uk

drm/i915: Fix use of engine->index for register offset

Since commit de1add360522 ("drm/i915: Decouple execbuf uAPI from internal
implementation") the index of the engine (its engine->id) in the
internal list no longer matches the hardware id. However, in a couple of
locations we missed fixing up the difference. In this case,
RING_FAULT_REG() refers to engine->id which is now not what the register
offset actually should be. Fortunately, in both case we should be more
or less looping over 0..I915_NUM_ENGINES.

Fixes: de1add360522 ("drm/i915: Decouple execbuf uAPI from internal...")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1469643077-2523-2-git-send-email-chris@chris-wilson.co.uk
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: stable@vger.kernel.org

Revert "drm/i915: Clean up associated VMAs on context destruction"

This reverts commit e9f24d5fb7cf3628b195b18ff3ac4e37937ceeae.

The patch was only a stop-gap measure that fixed half the problem - the
leak of the fbcon when restarting X. A complete solution required
releasing the VMA when the object itself was closed rather than rely on
file/process exit. The previous patches add the VMA tracking necessary
to do close them along with the object, context or file, and so the time
has come to remove the partial fix.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470293567-10811-28-git-send-email-chris@chris-wilson.co.uk

drm/i915: Mark the context and address space as closed

When the user closes the context mark it and the dependent address space
as closed. As we use an asynchronous destruct method, this has two
purposes.  First it allows us to flag the closed context and detect
internal errors if we to create any new objects for it (as it is removed
from the user's namespace, these should be internal bugs only). And
secondly, it allows us to immediately reap stale vma.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470293567-10811-27-git-send-email-chris@chris-wilson.co.uk

drm/i915: Release vma when the handle is closed

In order to prevent a leak of the vma on shared objects, we need to
hook into the object_close callback to destroy the vma on the object for
this file. However, if we destroyed that vma immediately we may cause
unexpected application stalls as we try to unbind a busy vma - hence we
defer the unbind to when we retire the vma.

v2: Keep vma allocated until closed. This is useful for a later
optimisation, but it is required now in order to handle potential
recursion of i915_vma_unbind() by retiring itself.
v3: Comments are important.

Testcase: igt/gem_ppggtt/flink-and-close-vma-leak
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470293567-10811-26-git-send-email-chris@chris-wilson.co.uk

drm/i915: Track active vma requests

Hook the vma itself into the i915_gem_request_retire() so that we can
accurately track when a solitary vma is inactive (as opposed to having
to wait for the entire object to be idle). This improves the interaction
when using multiple contexts (with full-ppgtt) and eliminates some
frequent list walking when retiring objects after a completed request.

A side-effect is that we get an active vma reference for free. The
consequence of this is shown in the next patch...

v2: Update inline names to be consistent with
i915_gem_object_get_active()

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470293567-10811-25-git-send-email-chris@chris-wilson.co.uk

drm/i915: i915_vma_move_to_active prep patch

This patch is broken out of the next just to remove the code motion from
that patch and make it more readable. What we do here is move the
i915_vma_move_to_active() to i915_gem_execbuffer.c and put the three
stages (read, write, fenced) together so that future modifications to
active handling are all located in the same spot. The importance of this
is so that we can more simply control the order in which the requests
are place in the retirement list (i.e. control the order at which we
retire and so control the lifetimes to avoid having to hold onto
references).

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470293567-10811-24-git-send-email-chris@chris-wilson.co.uk

drm/i915: Move request list retirement to i915_gem_request.c

As the list retirement is now clean of implementation details, we can
move it closer to the request management.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470293567-10811-23-git-send-email-chris@chris-wilson.co.uk

drm/i915: Double check activity before relocations

If the object is active and we need to perform a relocation upon it, we
need to take the slow relocation path. Before we do, double check the
active requests to see if they have completed.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470293567-10811-22-git-send-email-chris@chris-wilson.co.uk

drm/i915: s/__i915_wait_request/i915_wait_request/

There is only one wait on request function now, so drop the "expert"
indication of leading __.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470293567-10811-21-git-send-email-chris@chris-wilson.co.uk

drm/i915: Disable waitboosting for a saturated engine

If the user floods the GPU with so many requests that the engine stalls
waiting for free space, don't automatically promote the GPU to maximum
frequencies. If the GPU really is saturated with work, it will migrate
to high clocks by itself, otherwise it is merely a user flooding us with
busy-work.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470293567-10811-20-git-send-email-chris@chris-wilson.co.uk