Commit Graph

247 Commits

Author SHA1 Message Date
Tvrtko Ursulin
f4e2deceb6 drm/i915: Fix premature LRC unpin in GuC mode
In GuC mode LRC pinning lifetime depends exclusively on the
request liftime. Since that is terminated by the seqno update
that opens up a race condition between GPU finishing writing
out the context image and the driver unpinning the LRC.

To extend the LRC lifetime we will employ a similar approach
to what legacy ringbuffer submission does.

We will start tracking the last submitted context per engine
and keep it pinned until it is replaced by another one.

Note that the driver unload path is a bit fragile and could
benefit greatly from efforts to unify the legacy and exec
list submission code paths.

At the moment i915_gem_context_fini has special casing for the
two which are potentialy not needed, and also depends on
i915_gem_cleanup_ringbuffer running before itself.

v2:
 * Move pinning into engine->emit_request and actually fix
   the reference/unreference logic. (Chris Wilson)

 * ring->dev can be NULL on driver unload so use a different
   route towards it.

v3:
 * Rebase.
 * Handle the reset path. (Chris Wilson)
 * Exclude default context from the pinning - it is impossible
   to get it right before default context special casing in
   general is eliminated.

v4:
 * Rebased & moved context tracking to
   intel_logical_ring_advance_and_submit.

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Issue: VIZ-4277
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Nick Hoath <nicholas.hoath@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1453976997-25424-1-git-send-email-tvrtko.ursulin@linux.intel.com
2016-01-28 17:23:15 +00:00
Tvrtko Ursulin
321fe304f1 drm/i915: Make LRC pinning own a reference to the context
Will simplify the following fix and sounds logical.

v2: Add some whitespace to separate logic better. (Chris Wilson)

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Nick Hoath <nicholas.hoath@intel.com>
2016-01-28 17:23:15 +00:00
Tvrtko Ursulin
e5292823c1 drm/i915: Make LRC (un)pinning work on context and engine
Previously intel_lr_context_(un)pin were operating on requests
which is in conflict with their names.

If we make them take a context and an engine, it makes the names
make more sense and it also makes future fixes possible.

v2: Rebase for default_context/kernel_context change.

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Nick Hoath <nicholas.hoath@intel.com>
2016-01-28 17:23:15 +00:00
Alex Dai
397097b026 drm/i915/guc: Decouple GuC engine id from ring id
Previously GuC uses ring id as engine id because of same definition.
But this is not true since this commit:

commit de1add3605
Author: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Date:   Fri Jan 15 15:12:50 2016 +0000

    drm/i915: Decouple execbuf uAPI from internal implementation

Added GuC engine id into GuC interface to decouple it from ring id used
by driver.

v2: Keep ring name print out in debugfs; using for_each_ring() where
    possible to keep driver consistent. (Chris W.)

Signed-off-by: Alex Dai <yu.dai@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1453579094-29860-1-git-send-email-yu.dai@intel.com
2016-01-25 10:56:30 +00:00
Tvrtko Ursulin
77b04a0428 drm/i915: More use of the cached LRC state
Since:

commit 82352e908a
Author: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Date:   Fri Jan 15 17:12:45 2016 +0000

    drm/i915: Cache LRC state page in the context

and:

commit 0eb973d31d
Author: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Date:   Fri Jan 15 15:10:28 2016 +0000

    drm/i915: Cache ringbuffer GTT VMA

We can also remove the ring buffer start updates on every
context update since the address will not change for the
duration of the LRC pin.

For GuC we can remove the update altogether because it
only cares about the ring buffer start.

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Alex Dai <yu.dai@intel.com>
Cc: Dave Gordon <david.s.gordon@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/1453466567-33369-1-git-send-email-tvrtko.ursulin@linux.intel.com
2016-01-25 10:55:19 +00:00
Chris Wilson
426960bed3 drm/i915: Seal busy-ioctl uABI and prevent leaking of internal ids
Tvrtko was looking through the execbuffer-ioctl and noticed that the
uABI was tightly coupled to our internal engine identifiers. Close
inspection also revealed that we leak those internal engine identifiers
through the busy-ioctl, and those internal identifiers already do not
match the user identifiers. Fortuitiously, there is only one user of the
set of busy rings from the busy-ioctl, and they only wish to choose
between the RENDER and the BLT engines.

Let's fix the userspace ABI while we still can.

v2: Update the uAPI documentation to explain the identifiers.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Testcase: igt/gem_busy
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1452876706-21620-1-git-send-email-chris@chris-wilson.co.uk
2016-01-21 11:00:35 +00:00
Chris Wilson
7c17d37737 drm/i915: Use ordered seqno write interrupt generation on gen8+ execlists
Broadwell and later currently use the same unordered command sequence to
update the seqno in the HWS status page and then assert the user
interrupt. We should apply the w/a from legacy (where we do an mmio
read to delay the seqno read after the interrupt), but this is not
enough to enforce coherent seqno visibilty on Skylake. Rather than
search for the proper post-interrupt seqno barrier, use a strongly
ordered command sequence to write the seqno, then assert the user
interrupt from the ring.

v2: Move around the wa tail dwords to avoid adding duplicate code.

v3: Add references, comments on workarounds and bit5 check.

References: https://bugs.freedesktop.org/show_bug.cgi?id=93693
Testcase: igt/gem_ring_sync_loop #skl
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1453297415-17793-1-git-send-email-mika.kuoppala@intel.com
2016-01-21 11:53:09 +02:00
Dave Gordon
e28e404c3e drm/i915: tidy up a few leftovers
There are a few bits of code which the transformations implemented by
the previous patch reveal to be suboptimal, once the notion of a per-
ring default context has gone away. So this tidies up the leftovers.

It could have been squashed into the previous patch, but that would have
made that patch less clearly a simple transformation. In particular, any
change which alters the code block structure or indentation has been
deferred into this separate patch, because such things tend to make
diffs more difficult to read.

v4:	Rebased

Signed-off-by: Dave Gordon <david.s.gordon@intel.com>
Reviewed-by: Nick Hoath <nicholas.hoath@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1453230175-19330-4-git-send-email-david.s.gordon@intel.com
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2016-01-21 09:21:29 +01:00
Dave Gordon
ed54c1a1d1 drm/i915: abolish separate per-ring default_context pointers
Now that we've eliminated a lot of uses of ring->default_context,
we can eliminate the pointer itself.

All the engines share the same default intel_context, so we can just
keep a single reference to it in the dev_priv structure rather than one
in each of the engine[] elements. This make refcounting more sensible
too, as we now have a refcount of one for the one pointer, rather than
a refcount of one but multiple pointers.

From an idea by Chris Wilson.

v2:	transform an extra instance of ring->default_context introduced by
    42f1cae8c drm/i915: Restore inhibiting the load of the default context
    That patch's commentary includes:
	v2: Mark the global default context as uninitialized on GPU reset so
	    that the context-local workarounds are reloaded upon re-enabling
    The code implementing that now also benefits from the replacement of
    the multiple (per-ring) pointers to the default context with a single
    pointer to the unique kernel context.

v4:	Rebased, remove underused local (Nick Hoath)

Signed-off-by: Dave Gordon <david.s.gordon@intel.com>
Reviewed-by: Nick Hoath <nicholas.hoath@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/1453230175-19330-3-git-send-email-david.s.gordon@intel.com
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2016-01-21 09:21:29 +01:00
Dave Gordon
2682708839 drm/i915: simplify allocation of driver-internal requests
There are a number of places where the driver needs a request, but isn't
working on behalf of any specific user or in a specific context. At
present, we associate them with the per-engine default context. A future
patch will abolish those per-engine context pointers; but we can already
eliminate a lot of the references to them, just by making the allocator
allow NULL as a shorthand for "an appropriate context for this ring",
which will mean that the callers don't need to know anything about how
the "appropriate context" is found (e.g. per-ring vs per-device, etc).

So this patch renames the existing i915_gem_request_alloc(), and makes
it local (static inline), and replaces it with a wrapper that provides
a default if the context is NULL, and also has a nicer calling
convention (doesn't require a pointer to an output parameter). Then we
change all callers to use the new convention:
OLD:
	err = i915_gem_request_alloc(ring, user_ctx, &req);
	if (err) ...
NEW:
	req = i915_gem_request_alloc(ring, user_ctx);
	if (IS_ERR(req)) ...
OLD:
	err = i915_gem_request_alloc(ring, ring->default_context, &req);
	if (err) ...
NEW:
	req = i915_gem_request_alloc(ring, NULL);
	if (IS_ERR(req)) ...

v4:	Rebased

Signed-off-by: Dave Gordon <david.s.gordon@intel.com>
Reviewed-by: Nick Hoath <nicholas.hoath@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1453230175-19330-2-git-send-email-david.s.gordon@intel.com
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2016-01-21 09:21:29 +01:00
Tvrtko Ursulin
82352e908a drm/i915: Cache LRC state page in the context
LRC lifetime is well defined so we can cache the page pointing
to the object backing store in the context in order to avoid
walking over the object SG page list from the interrupt context
without the big lock held.

v2: Also cache the mapping. (Chris Wilson)
v3: Unmap on the error path.
v4: No need to cache the page. (Chris Wilson)
v5: No need to dirty the page on unpin. (Chris Wilson)
v6: kmap() cannot fail and use kmap_to_page to simplify unpin.
    (Chris Wilson)

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Dave Gordon <david.s.gordon@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/1452877965-32042-1-git-send-email-tvrtko.ursulin@linux.intel.com
2016-01-18 09:58:44 +00:00
Tvrtko Ursulin
0eb973d31d drm/i915: Cache ringbuffer GTT VMA
Purpose is to avoid calling i915_gem_obj_ggtt_offset from the
interrupt context without the big lock held.

v2: Renamed gtt_start to gtt_offset. (Daniel Vetter)
v3: Cache the VMA instead of address. (Chris Wilson)

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/1452870629-13830-2-git-send-email-tvrtko.ursulin@linux.intel.com
2016-01-18 09:58:40 +00:00
Tvrtko Ursulin
ca82580c9c drm/i915: Do not call API requiring struct_mutex where it is not available
LRC code was calling GEM API like i915_gem_obj_ggtt_offset from
places where the struct_mutex cannot be grabbed (irq handlers).

To avoid that this patch caches some interesting bits and values
in the engine and context structures.

Some usages are also removed where they are not needed like a
few asserts which are either impossible or have been checked
already during engine initialization.

Side benefit is also that interrupt handlers and command
submission stop evaluating invariant conditionals, like what
Gen we are running on, on every interrupt and every command
submitted.

This patch deals with logical ring context id and descriptors
while subsequent patches will deal with the remaining issues.

v2:
 * Cache the VMA instead of the address. (Chris Wilson)
 * Incorporate Dave Gordon's good comments and function name.

v3:
 * Extract ctx descriptor template to a function and group
   functions dealing with ctx descriptor & co together near
   top of the file. (Dave Gordon)

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Dave Gordon <david.s.gordon@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1452870629-13830-1-git-send-email-tvrtko.ursulin@linux.intel.com
2016-01-18 09:58:36 +00:00
Francisco Jerez
965fd602a6 drm/i915: Make sure DC writes are coherent on flush.
We need to set the DC FLUSH PIPE_CONTROL bit on Gen7+ to guarantee
that writes performed via the HDC are visible in memory.  Fixes an
intermittent failure in a Piglit test that writes to a BO from a
shader using GL atomic counters (implemented as HDC untyped atomics)
and then expects the memory to read back the same value after mapping
it on the CPU.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=91298
Tested-by: Mark Janes <mark.a.janes@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Francisco Jerez <currojerez@riseup.net>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1452740379-3194-1-git-send-email-currojerez@riseup.net
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
2016-01-15 11:33:52 +02:00
Tvrtko Ursulin
ec8a9776cc drm/i915: Fix bsd2 ring name
Chris Wilson noticed the "bds2" typo.

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/1452619956-27014-3-git-send-email-tvrtko.ursulin@linux.intel.com
2016-01-13 10:02:52 +00:00
Tvrtko Ursulin
d9f3af96c2 drm/i915: Compact logical ring interrupt initialization
Identically to vfuncs interrupt mask initialization can also be
compacted for more readable code.

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/1452619956-27014-2-git-send-email-tvrtko.ursulin@linux.intel.com
2016-01-13 10:02:36 +00:00
Tvrtko Ursulin
c9cacf9349 drm/i915: Extract vfunc setup from logical ring initializers
Majority of them was duplicated code and only render ring
currently overrides some of them. We can save some lines of
code and also take away the confusion on why bsd2 did not
do the seqno coherency workaround. (VCS2 ring does not exist
on platforms where workaround is needed but that was not
documented in the code.)

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/1452619956-27014-1-git-send-email-tvrtko.ursulin@linux.intel.com
2016-01-13 10:02:05 +00:00
Tvrtko Ursulin
7eb08a25a4 drm/i915/bdw+: Replace list_del+list_add_tail with list_move_tail
Same effect for slightly less source code and resulting binary.

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1452521321-4032-2-git-send-email-tvrtko.ursulin@linux.intel.com
2016-01-12 10:30:40 +00:00
Boyer, Wayne
cd7feaaad6 drm/i915: Don't warn if the workaround list is empty part 2.
Extend the same reasoning as in the patch listed below.  It's not an
error for the workaround list to be empty if no workarounds are needed.

    commit 02235808b6
    Author: Francisco Jerez <currojerez@riseup.net>
    Date:   Wed Oct 7 14:44:01 2015 +0300
        drm/i915: Don't warn if the workaround list is empty.

Signed-off-by: Wayne Boyer <wayne.boyer@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1452129330-3484-2-git-send-email-rodrigo.vivi@intel.com
2016-01-08 10:14:30 -08:00
Ben Widawsky
91a4103206 drm/i915: Extract CSB status read
This is a useful thing to have around as a function because the mechanism may
change in the future.

There is a net increase in LOC here, and it will continue to be the case on GEN8
and GEN9 - but future GENs may have an alternate mechanism for doing this.

Signed-off-by: Ben Widawsky <benjamin.widawsky@intel.com>
Reviewed-by: Michel Thierry <michel.thierry@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1452018609-10142-4-git-send-email-benjamin.widawsky@intel.com
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2016-01-07 15:34:41 +01:00
Ben Widawsky
f764a8b146 drm/i915: Change WARN to ERROR in CSB count
There is no point in emitting a WARN since the backtrace will always be the
same. Errors have actually become easier to spot given the large number of WARNs
which exist today in modesetting paths.

Signed-off-by: Ben Widawsky <benjamin.widawsky@intel.com>
Reviewed-by: Michel Thierry <michel.thierry@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1452018609-10142-3-git-send-email-benjamin.widawsky@intel.com
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2016-01-07 15:34:41 +01:00
Ben Widawsky
5590a5f0af drm/i915: Cleanup some of the CSB handling
I think this patch is a worthwhile cleanup even if it might look only marginally
useful. It gets more useful in upcoming patches and for handling of future GEN
platforms.

The only non-mechanical part of this is the removal of the extra & operation on
the ring->next_context_status_buffer. This is safe because right above this, we
already did a modulus operation.

Signed-off-by: Ben Widawsky <benjamin.widawsky@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1452018609-10142-2-git-send-email-benjamin.widawsky@intel.com
Reviewed-by: Michel Thierry <michel.thierry@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2016-01-07 15:34:41 +01:00
Dave Gordon
c5d46ee206 drm/i915: add kerneldoc for intel_lr_context_size()
This function was recently renamed & exposed, so now it gets documented

Signed-off-by: Dave Gordon <david.s.gordon@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1451996493-16079-1-git-send-email-david.s.gordon@intel.com
2016-01-05 16:14:33 +01:00
Dave Gordon
95a66f7e71 drm/i915/guc: Expose (intel)_lr_context_size()
The GuC code needs to know the size of a logical context, so we
expose get_lr_context_size(), renaming it intel_lr_context__size()
to fit the naming conventions for nonstatic functions.

For: VIZ-2021
Signed-off-by: Dave Gordon <david.s.gordon@intel.com>
Signed-off-by: Alex Dai <yu.dai@intel.com>
Reviewed-by: Dave Gordon <david.s.gordon@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1450468812-4882-2-git-send-email-yu.dai@intel.com
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2016-01-05 11:33:34 +01:00
Alex Dai
a7e02199ae drm/i915/guc: Move GuC wq_check_space to alloc_request_extras
Split GuC work queue space checking from submission and move it to
ring_alloc_request_extras. The reason is that failure in later
i915_add_request() won't be handled. In the case timeout happens,
driver can return early in order to handle the error.

v1: Move wq_reserve_space to ring_reserve_space
v2: Move wq_reserve_space to alloc_request_extras (Chris Wilson)
v3: The work queue head pointer is cached by driver now. So we can
    quickly return if space is available.
    s/reserve/check/g (Dave Gordon)
v4: Update cached wq head after ring doorbell; check wq space before
    ring doorbell in case unexpected error happens; call wq space
    check only when GuC submission is enabled. (Dave Gordon)

Signed-off-by: Alex Dai <yu.dai@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1450295155-10050-1-git-send-email-yu.dai@intel.com
Reviewed-by: Dave Gordon <david.s.gordon@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2016-01-05 11:07:32 +01:00
Ben Widawsky
eba51190f3 drm/i915: Fix whitespace (trivial)
Signed-off-by: Ben Widawsky <benjamin.widawsky@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1451427643-7266-1-git-send-email-benjamin.widawsky@intel.com
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
2015-12-30 11:19:50 +02:00
Ben Widawsky
1a5a9ce70f drm/i915: Limit VF cache invalidate workaround usage to gen9
It is unclear if this is even required on BXT.

v2: Make sure to set the default value to false. Uncertain how my compiler
doesn't complain with v1.

Cc: Imre Deak <imre.deak@intel.com>
Signed-off-by: Ben Widawsky <benjamin.widawsky@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1450374597-7021-1-git-send-email-benjamin.widawsky@intel.com
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-12-21 13:05:36 +01:00
Dave Gordon
033908aed5 drm/i915: mark GEM object pages dirty when mapped & written by the CPU
In various places, a single page of a (regular) GEM object is mapped into
CPU address space and updated. In each such case, either the page or the
the object should be marked dirty, to ensure that the modifications are
not discarded if the object is evicted under memory pressure.

The typical sequence is:
	va = kmap_atomic(i915_gem_object_get_page(obj, pageno));
	*(va+offset) = ...
	kunmap_atomic(va);

Here we introduce i915_gem_object_get_dirty_page(), which performs the
same operation as i915_gem_object_get_page() but with the side-effect
of marking the returned page dirty in the pagecache.  This will ensure
that if the object is subsequently evicted (due to memory pressure),
the changes are written to backing store rather than discarded.

Note that it works only for regular (shmfs-backed) GEM objects, but (at
least for now) those are the only ones that are updated in this way --
the objects in question are contexts and batchbuffers, which are always
shmfs-backed.

Separate patches deal with the cases where whole objects are (or may
be) dirtied.

v3: Mark two more pages dirty in the page-boundary-crossing
    cases of the execbuffer relocation code [Chris Wilson]

Signed-off-by: Dave Gordon <david.s.gordon@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/1449773486-30822-2-git-send-email-david.s.gordon@intel.com
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-12-11 18:11:53 +01:00
Dave Gordon
b0366a54b4 drm/i915: intel_ring_initialized() must be simple and inline
Based on Chris Wilson's patch from 6 months ago, rebased and adapted.

The current implementation of intel_ring_initialized() is too heavyweight;
it's a non-inlined function that chases several levels of pointers. This
wouldn't matter too much if it were rarely called, but it's used inside
the iterator test of for_each_ring() and is therefore called quite
frequently. So let's make it simple and inline ...

The idea here is to use ring->dev as an indicator showing which engines
have been initialised and are therefore to be included in iterations that
use for_each_ring(). This allows us to avoid multiple memory references
and a (non-inlined) function call on each iteration of each such loop.

	Fixes regression from
	commit 48d823878d
	Author: Oscar Mateo <oscar.mateo@intel.com>
	Date:   Thu Jul 24 17:04:23 2014 +0100

	    drm/i915/bdw: Generic logical ring init and cleanup

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Dave Gordon <david.s.gordon@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1449586956-32360-2-git-send-email-david.s.gordon@intel.com
2015-12-10 14:14:36 +01:00
Daniel Vetter
af3302b907 Revert "drm/i915: Extend LRC pinning to cover GPU context writeback"
This reverts commit 6d65ba943a.

Mika Kuoppala traced down a use-after-free crash in module unload to
this commit, because ring->last_context is leaked beyond when the
context gets destroyed. Mika submitted a quick fix to patch that up in
the context destruction code, but that's too much of a hack.

The right fix is instead for the ring to hold a full reference onto
it's last context, like we do for legacy contexts.

Since this is causing a regression in BAT it gets reverted before we
can close this.

Cc: Nick Hoath <nicholas.hoath@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: David Gordon <david.s.gordon@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Alex Dai <yu.dai@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=93248
Acked-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
2015-12-04 17:34:40 +01:00
Nick Hoath
6d65ba943a drm/i915: Extend LRC pinning to cover GPU context writeback
Use the first retired request on a new context to unpin
the old context. This ensures that the hw context remains
bound until it has been written back to by the GPU.
Now that the context is pinned until later in the request/context
lifecycle, it no longer needs to be pinned from context_queue to
retire_requests.
This fixes an issue with GuC submission where the GPU might not
have finished writing back the context before it is unpinned. This
results in a GPU hang.

v2: Moved the new pin to cover GuC submission (Alex Dai)
    Moved the new unpin to request_retire to fix coverage leak
v3: Added switch to default context if freeing a still pinned
    context just in case the hw was actually still using it
v4: Unwrapped context unpin to allow calling without a request
v5: Only create a switch to idle context if the ring doesn't
    already have a request pending on it (Alex Dai)
    Rename unsaved to dirty to avoid double negatives (Dave Gordon)
    Changed _no_req postfix to __ prefix for consistency (Dave Gordon)
    Split out per engine cleanup from context_free as it
    was getting unwieldy
    Corrected locking (Dave Gordon)
v6: Removed some bikeshedding (Mika Kuoppala)
    Added explanation of the GuC hang that this fixes (Daniel Vetter)
v7: Removed extra per request pinning from ring reset code (Alex Dai)
    Added forced ring unpin/clean in error case in context free (Alex Dai)

Signed-off-by: Nick Hoath <nicholas.hoath@intel.com>
Issue: VIZ-4277
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: David Gordon <david.s.gordon@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Alex Dai <yu.dai@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Alex Dai <yu.dai@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-12-03 15:11:55 +01:00
Daniel Vetter
92907cbbef Linux 4.4-rc2
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Merge tag 'v4.4-rc2' into drm-intel-next-queued

Linux 4.4-rc2

Backmerge to get at

commit 1b0e3a049e
Author: Imre Deak <imre.deak@intel.com>
Date:   Thu Nov 5 23:04:11 2015 +0200

    drm/i915/skl: disable display side power well support for now

so that we can proplery re-eanble skl power wells in -next.

Conflicts are just adjacent lines changed, except for intel_fbdev.c
where we need to interleave the changs. Nothing nefarious.

Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
2015-11-23 09:04:05 +01:00
Arun Siluvery
fb1a21114f Revert "drm/i915: Initialize HWS page address after GPU reset"
This reverts commit 2e5356da37.

It is now redundant as it is already covered in below commit which introduced
the changes to reuse initialization of resources in resume/reset path.

commit e84fe80337
Author: Nick Hoath <nicholas.hoath@intel.com>
Date:   Fri Sep 11 12:53:46 2015 +0100

    drm/i915: Split alloc from init for lrc

lrc_setup_hardware_status_page() in the same function gen8_init_common_ring()
takes care of this.

Cc: Nick Hoath <nicholas.hoath@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Arun Siluvery <arun.siluvery@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1447951664-9347-1-git-send-email-arun.siluvery@linux.intel.com
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-11-19 17:51:16 +01:00
Ville Syrjälä
f0f59a00a1 drm/i915: Type safe register read/write
Make I915_READ and I915_WRITE more type safe by wrapping the register
offset in a struct. This should eliminate most of the fumbles we've had
with misplaced parens.

This only takes care of normal mmio registers. We could extend the idea
to other register types and define each with its own struct. That way
you wouldn't be able to accidentally pass the wrong thing to a specific
register access function.

The gpio_reg setup is probably the ugliest thing left. But I figure I'd
just leave it for now, and wait for some divine inspiration to strike
before making it nice.

As for the generated code, it's actually a bit better sometimes. Eg.
looking at i915_irq_handler(), we can see the following change:
  lea    0x70024(%rdx,%rax,1),%r9d
  mov    $0x1,%edx
- movslq %r9d,%r9
- mov    %r9,%rsi
- mov    %r9,-0x58(%rbp)
- callq  *0xd8(%rbx)
+ mov    %r9d,%esi
+ mov    %r9d,-0x48(%rbp)
 callq  *0xd8(%rbx)

So previously gcc thought the register offset might be signed and
decided to sign extend it, just in case. The rest appears to be
mostly just minor shuffling of instructions.

v2: i915_mmio_reg_{offset,equal,valid}() helpers added
    s/_REG/_MMIO/ in the register defines
    mo more switch statements left to worry about
    ring_emit stuff got sorted in a prep patch
    cmd parser, lrc context and w/a batch buildup also in prep patch
    vgpu stuff cleaned up and moved to a prep patch
    all other unrelated changes split out
v3: Rebased due to BXT DSI/BLC, MOCS, etc.
v4: Rebased due to churn, s/i915_mmio_reg_t/i915_reg_t/

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/1447853606-2751-1-git-send-email-ville.syrjala@linux.intel.com
2015-11-18 15:39:11 +02:00
Ville Syrjälä
0d925ea023 drm/i915: Wrap context LRI init in a macro
We set up a load of LRIs in the logical ring context. Wrap that stuff
in a macro to avoid typos with position of each reg/value pair in the
context. This also makes it easier to make the register defines type
safe.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1446672017-24497-24-git-send-email-ville.syrjala@linux.intel.com
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
2015-11-18 14:35:39 +02:00
Ville Syrjälä
35dc3f97a6 drm/i915: Give names to more ring registers
The logical render context population has a bunch of raw ring register
offsets. Use the names we have for them, and in cases where we we don't,
give them names.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1446672017-24497-23-git-send-email-ville.syrjala@linux.intel.com
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
2015-11-18 14:35:36 +02:00
Ville Syrjälä
9244a81701 drm/i915: Wrap ASSIGN_CTX_{PDP,PM4L} in do {} while(0)
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1446672017-24497-22-git-send-email-ville.syrjala@linux.intel.com
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
2015-11-18 14:35:32 +02:00
Ville Syrjälä
8f40db776a drm/i915: Add wa_ctx_emit_reg()
Add a helper for emitting register offsets (for LRI/SRM) into the w/a
batch buffer.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1446672017-24497-21-git-send-email-ville.syrjala@linux.intel.com
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
2015-11-18 14:35:28 +02:00
Ville Syrjälä
f92a916220 drm/i915: Add functions to emit register offsets to the ring
When register type safety happens, we can't just try to emit the
register itself to the ring. Instead we'll need to extract the
offset from it first. Add some convenience functions that will do
that.

v2: Convert MOCS setup too

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1446672017-24497-20-git-send-email-ville.syrjala@linux.intel.com
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
2015-11-18 14:35:24 +02:00
Linus Torvalds
3e82806b97 Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux
Pull drm updates from Dave Airlie:
 "I Was Almost Tempted To Capitalise Every Word, but then I decided I
  couldn't read it myself!

  I've also got one pull request for the sti driver outstanding.  It
  relied on a commit in Greg's tree and I didn't find out in time, that
  commit is in your tree now so I might send that along once this is
  merged.

  I also had the accidental misfortune to have access to a Skylake on my
  desk for a few days, and I've had to encourage Intel to try harder,
  which seems to be happening now.

  Here is the main drm-next pull request for 4.4.

  Highlights:

  New driver:
        vc4 driver for the Rasberry Pi VPU.
        (From Eric Anholt at Broadcom.)

  Core:
        Atomic fbdev support
        Atomic helpers for runtime pm
        dp/aux i2c STATUS_UPDATE handling
        struct_mutex usage cleanups.
        Generic of probing support.

  Documentation:
        Kerneldoc for VGA switcheroo code.
        Rename to gpu instead of drm to reflect scope.

  i915:
        Skylake GuC firmware fixes
        HPD A support
        VBT backlight fallbacks
        Fastboot by default for some systems
        FBC work
        BXT/SKL workarounds
        Skylake deeper sleep state fixes

  amdgpu:
        Enable GPU scheduler by default
        New atombios opcodes
        GPUVM debugging options
        Stoney support.
        Fencing cleanups.

  radeon:
        More efficient CS checking

  nouveau:
        gk20a instance memory handling improvements.
        Improved PGOB detection and GK107 support
        Kepler GDDR5 PLL statbility improvement
        G8x/GT2xx reclock improvements
        new userspace API compatiblity fixes.

  virtio-gpu:
        Add 3D support - qemu 2.5 has it merged for it's gtk backend.

  msm:
        Initial msm88896 (snapdragon 8200)

  exynos:
        HDMI cleanups
        Enable mixer driver byt default
        Add DECON-TV support

  vmwgfx:
        Move to using memremap + fixes.

  rcar-du:
        Add support for R8A7793/4 DU

  armada:
        Remove support for non-component mode
        Improved plane handling
        Power savings while in DPMS off.

  tda998x:
        Remove unused slave encoder support
        Use more HDMI helpers
        Fix EDID read handling

  dwhdmi:
        Interlace video mode support for ipu-v3/dw_hdmi
        Hotplug state fixes
        Audio driver integration

  imx:
        More color formats support.

  tegra:
        Minor fixes/improvements"

[ Merge fixup: remove unused variable 'dev' that had all uses removed in
  commit 4e270f0880: "drm/gem: Drop struct_mutex requirement from
  drm_gem_mmap_obj" ]

* 'drm-next' of git://people.freedesktop.org/~airlied/linux: (764 commits)
  drm/vmwgfx: Relax irq locking somewhat
  drm/vmwgfx: Properly flush cursor updates and page-flips
  drm/i915/skl: disable display side power well support for now
  drm/i915: Extend DSL readout fix to BDW and SKL.
  drm/i915: Do graphics device reset under forcewake
  drm/i915: Skip fence installation for objects with rotated views (v4)
  vga_switcheroo: Drop client power state VGA_SWITCHEROO_INIT
  drm/amdgpu: group together common fence implementation
  drm/amdgpu: remove AMDGPU_FENCE_OWNER_MOVE
  drm/amdgpu: remove now unused fence functions
  drm/amdgpu: fix fence fallback check
  drm/amdgpu: fix stoping the scheduler timeout
  drm/amdgpu: cleanup on error in amdgpu_cs_ioctl()
  drm/i915: Fix locking around GuC firmware load
  drm/amdgpu: update Fiji's Golden setting
  drm/amdgpu: update Fiji's rev id
  drm/amdgpu: extract common code in vi_common_early_init
  drm/amd/scheduler: don't oops on failure to load
  drm/amdgpu: don't oops on failure to load (v2)
  drm/amdgpu: don't VT switch on suspend
  ...
2015-11-10 09:33:06 -08:00
Tim Gore
cbdc12a9fc drm/i915: make A0 wa's applied to A1
Since A1 chips use the same GPU as A0, they need all the
same wa's in the i915 driver. Update some conditionals
to do this.

Signed-off-by: Tim Gore <tim.gore@intel.com>
Reviewed-by: Arun Siluvery <arun.siluvery@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1445856538-5417-1-git-send-email-tim.gore@intel.com
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
2015-10-29 15:39:15 +02:00
Chris Wilson
608c1a526c drm/i915: Recover all available ringbuffer space following reset
Having flushed all requests from all queues, we know that all
ringbuffers must now be empty. However, since we do not reclaim
all space when retiring the request (to prevent HEADs colliding
with rapid ringbuffer wraparound) the amount of available space
on each ringbuffer upon reset is less than when we start. Do one
more pass over all the ringbuffers to reset the available space

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Cc: Arun Siluvery <arun.siluvery@linux.intel.com>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Cc: Dave Gordon <david.s.gordon@intel.com>
2015-10-28 17:10:31 +00:00
Jani Nikula
e87a005d90 drm/i915: add helpers for platform specific revision id range checks
Revision checks are almost always accompanied by a platform check. (The
exceptions are platform specific code.) Add helpers to check for a
platform and a revision range: IS_SKL_REVID() and IS_BXT_REVID(). In
most places this simplifies and clarifies the code. It will be obvious
that revid macros are used for the correct platform.

This should make it easier to find all the revision checks for
workarounds for each platform, and make it easier to remove them once we
drop support for early hardware revisions.

This should also make it easier to differentiate between Skylake and
Kabylake revision checks when Kabylake support is added.

v2: rebase

Acked-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1445343722-3312-3-git-send-email-jani.nikula@intel.com
2015-10-21 11:25:01 +03:00
Jani Nikula
fffda3f4fb drm/i915/bxt: add revision id for A1 stepping and use it
Prefer inclusive ranges for revision checks rather than "below B0". Per
specs A2 is not used, so revid <= A1 matches revid < B0.

Acked-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1445343722-3312-2-git-send-email-jani.nikula@intel.com
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
2015-10-21 11:25:01 +03:00
Dave Airlie
2dd3a88ac8 Merge tag 'drm-intel-next-2015-10-10' of git://anongit.freedesktop.org/drm-intel into drm-next
- dmc fixes from Animesh (not yet all) for deeper sleep states
- piles of prep patches from Ville to make mmio functions type-safe
- more fbc work from Paulo all over
- w/a shuffling from Arun Siluvery
- first part of atomic watermark updates from Matt and Ville (later parts had to
  be dropped again unfortunately)
- lots of patches to prepare bxt dsi support ( Shashank Sharma)
- userptr fixes from Chris
- audio rate interface between i915/snd_hda plus kerneldoc (Libin Yang)
- shrinker improvements and fixes (Chris Wilson)
- lots and lots of small patches all over

* tag 'drm-intel-next-2015-10-10' of git://anongit.freedesktop.org/drm-intel: (134 commits)
  drm/i915: Update DRIVER_DATE to 20151010
  drm/i915: Partial revert of atomic watermark series
  drm/i915: Early exit from semaphore_waits_for for execlist mode.
  drm/i915: Remove wrong warning from i915_gem_context_clean
  drm/i915: Determine the stolen memory base address on gen2
  drm/i915: fix FBC buffer size checks
  drm/i915: fix CFB size calculation
  drm/i915: remove pre-atomic check from SKL update_primary_plane
  drm/i915: don't allocate fbcon from stolen memory if it's too big
  Revert "drm/i915: Call encoder hotplug for init and resume cases"
  Revert "drm/i915: Add hot_plug hook for hdmi encoder"
  drm/i915: use error path
  drm/i915/irq: Fix misspelled word register in kernel-doc
  drm/i915/irq: Fix kernel-doc warnings
  drm/i915: Hook up ring workaround writes at context creation time on Gen6-7.
  drm/i915: Don't warn if the workaround list is empty.
  drm/i915: Resurrect golden context on gen6/7
  drm/i915/chv: remove pre-production hardware workarounds
  drm/i915/snb: remove pre-production hardware workaround
  drm/i915/bxt: Set time interval unit to 0.833us
  ...
2015-10-20 09:00:01 +10:00
Dave Airlie
48f87dd146 Merge commit '06d1ee32a4d25356a710b49d5e95dbdd68bdf505' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux into drm-next
Backmerge the drm-fixes pull from Linus's tree into drm-next.

This is to fix some conflicts and make future pulls cleaner
2015-10-16 10:25:28 +10:00
Chris Wilson
40a24488f5 drm/i915: Flush pipecontrol post-sync writes
In order to flush the results from in-batch pipecontrol writes (used for
example in glQuery) before declaring the batch complete (and so declaring
the query results coherent), we need to set the FlushEnable bit in our
flushing pipecontrol. The FlushEnable bit "waits until all previous
writes of immediate data from post-sync circles are complete before
executing the next command".

I get GPU hangs on byt without flushing these writes (running ue4).
piglit has examples where the flush is required for correct rendering.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Acked-by: Daniel Vetter <daniel@ffwll.ch>
Cc: stable@vger.kernel.org
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
2015-10-13 16:54:19 +03:00
Chris Wilson
2f5945bc90 drm/i915: Kill DRI1 cliprects
Passing cliprects into the kernel for it to re-execute the batch buffer
with different CMD_DRAWRECT died out long ago. As DRI1 support has been
removed from the kernel, we can now simply reject any execbuf trying to
use this "feature".

To keep Daniel happy with the prospect of being able to reuse these
fields in the next decade, continue to ensure that current userspace is
not passing garbage in through the dead fields.

v2: Fix the cliprects_ptr check

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Dave Gordon <david.s.gordon@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-10-07 16:05:41 +02:00
Michel Thierry
dfc53c5e73 drm/i915: Consider HW CSB write pointer before resetting the sw read pointer
A previous commit resets the Context Status Buffer (CSB) read pointer in
ring init
    commit c0a03a2e4c ("drm/i915: Reset CSB read pointer in ring init")

This is generally correct, but this pointer is not reset after
suspend/resume in some platforms (cht). In this case, the driver should
read the register value instead of resetting the sw read counter to 0.
Otherwise we process old events, leading to unwanted pre-emptions or
something worse.

But in other platforms (bdw) and also during GPU reset or power up, the
CSBWP is reset to 0x7 (an invalid number), and in this case the read
pointer should be set to 5 (the interrupt code will increment this
counter one more time, and will start reading from CSB[0]).

v2: When the CSB registers are reset, the read pointer needs to be set
to 5, otherwise the first write (CSB[0]) won't be read (Mika).
Replace magic numbers with GEN8_CSB_ENTRIES (6) and GEN8_CSB_PTR_MASK
(0x07).

Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: stable@vger.kernel.org # v4.0+
Signed-off-by: Lei Shen <lei.shen@intel.com>
Signed-off-by: Deepak S <deepak.s@intel.com>
Signed-off-by: Michel Thierry <michel.thierry@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
2015-09-28 17:23:19 +03:00
Nick Hoath
cd1736ad0a drm/i915: Remove extraneous request cancel.
Remove extraneous request cancel in request allocation failure path
in intel_lr_context_deferred_alloc (Tvrtko Ursulin)

Regression from:

  commit e84fe80337
  Author: Nick Hoath <nicholas.hoath@intel.com>
  Date:   Fri Sep 11 12:53:46 2015 +0100

      drm/i915: Split alloc from init for lrc

Signed-off-by: Nick Hoath <nicholas.hoath@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-09-23 17:33:55 +02:00