Updated a couple of trace points to use the now cached request pointer rather
than extracting it from the ring.
For: VIZ-5115
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Reviewed-by: Tomas Elf <tomas.elf@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The alloc_request() function does not actually return the newly allocated
request. Instead, it must be pulled from ring->outstanding_lazy_request. This
patch fixes this so that code can create a request and start using it knowing
exactly which request it actually owns.
v2: Updated for new i915_gem_request_alloc() scheme.
For: VIZ-5115
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Reviewed-by: Tomas Elf <tomas.elf@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Shrunk the parameter list of i915_gem_execbuffer_retire_commands() to a single
structure as everything it requires is available in the execbuff_params object.
For: VIZ-5115
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Reviewed-by: Tomas Elf <tomas.elf@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The do_execbuf() function takes quite a few parameters. The actual set of
parameters is going to change with the conversion to passing requests around.
Further, it is due to grow massively with the arrival of the GPU scheduler.
This patch simplifies the prototype by passing a parameter structure instead.
Changing the parameter set in the future is then simply a matter of
adding/removing items to the structure.
Note that the structure does not contain absolutely everything that is passed
in. This is because the intention is to use this structure more extensively
later in this patch series and more especially in the GPU scheduler that is
coming soon. The latter requires hanging on to the structure as the final
hardware submission can be delayed until long after the execbuf IOCTL has
returned to user land. Thus it is unsafe to put anything in the structure that
is local to the IOCTL call itself - such as the 'args' parameter. All entries
must be copies of data or pointers to structures that are reference counted in
some way and guaranteed to exist for the duration of the batch buffer's life.
v2: Rebased to newer tree and updated for changes to the command parser.
Specifically, a code shuffle has required saving the batch start address in the
params structure.
For: VIZ-5115
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Reviewed-by: Tomas Elf <tomas.elf@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
In execlist mode, the context object pointer is written in to the request
structure (and reference counted) at the point of request creation. In legacy
mode, this only happens inside i915_add_request().
This patch updates the legacy code path to match the execlist version. This
allows all the intermediate code between request creation and request submission
to get at the context object given only a request structure. Thus negating the
need to pass context pointers here, there and everywhere.
v2: Moved the context reference so it does not need to be undone if the
get_seqno() fails.
v3: Fixed execlist mode always hitting a warning about invalid last_contexts
(which don't exist in execlist mode).
v4: Updated for new i915_gem_request_alloc() scheme.
For: VIZ-5115
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Reviewed-by: Tomas Elf <tomas.elf@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The i915_add_request() function is called to keep track of work that has been
written to the ring buffer. It adds epilogue commands to track progress (seqno
updates and such), moves the request structure onto the right list and other
such house keeping tasks. However, the work itself has already been written to
the ring and will get executed whether or not the add request call succeeds. So
no matter what goes wrong, there isn't a whole lot of point in failing the call.
At the moment, this is fine(ish). If the add request does bail early on and not
do the housekeeping, the request will still float around in the
ring->outstanding_lazy_request field and be picked up next time. It means
multiple pieces of work will be tagged as the same request and driver can't
actually wait for the first piece of work until something else has been
submitted. But it all sort of hangs together.
This patch series is all about removing the OLR and guaranteeing that each piece
of work gets its own personal request. That means that there is no more
'hoovering up of forgotten requests'. If the request does not get tracked then
it will be leaked. Thus the add request call _must_ not fail. The previous patch
should have already ensured that it _will_ not fail by removing the potential
for running out of ring space. This patch enforces the rule by actually removing
the early exit paths and the return code.
Note that if something does manage to fail and the epilogue commands don't get
written to the ring, the driver will still hang together. The request will be
added to the tracking lists. And as in the old case, any subsequent work will
generate a new seqno which will suffice for marking the old one as complete.
v2: Improved WARNings (Tomas Elf review request).
For: VIZ-5115
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Reviewed-by: Tomas Elf <tomas.elf@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
It is a bad idea for i915_add_request() to fail. The work will already have been
send to the ring and will be processed, but there will not be any tracking or
management of that work.
The only way the add request call can fail is if it can't write its epilogue
commands to the ring (cache flushing, seqno updates, interrupt signalling). The
reasons for that are mostly down to running out of ring buffer space and the
problems associated with trying to get some more. This patch prevents that
situation from happening in the first place.
When a request is created, it marks sufficient space as reserved for the
epilogue commands. Thus guaranteeing that by the time the epilogue is written,
there will be plenty of space for it. Note that a ring_begin() call is required
to actually reserve the space (and do any potential waiting). However, that is
not currently done at request creation time. This is because the ring_begin()
code can allocate a request. Hence calling begin() from the request allocation
code would lead to infinite recursion! Later patches in this series remove the
need for begin() to do the allocate. At that point, it becomes safe for the
allocate to call begin() and really reserve the space.
Until then, there is a potential for insufficient space to be available at the
point of calling i915_add_request(). However, that would only be in the case
where the request was created and immediately submitted without ever calling
ring_begin() and adding any work to that request. Which should never happen. And
even if it does, and if that request happens to fall down the tiny window of
opportunity for failing due to being out of ring space then does it really
matter because the request wasn't doing anything in the first place?
v2: Updated the 'reserved space too small' warning to include the offending
sizes. Added a 'cancel' operation to clean up when a request is abandoned. Added
re-initialisation of tracking state after a buffer wrap to keep the sanity
checks accurate.
v3: Incremented the reserved size to accommodate Ironlake (after finally
managing to run on an ILK system). Also fixed missing wrap code in LRC mode.
v4: Added extra comment and removed duplicate WARN (feedback from Tomas).
For: VIZ-5115
CC: Tomas Elf <tomas.elf@intel.com>
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
In Indirect context w/a batch buffer,
+WaFlushCoherentL3CacheLinesAtContextSwitch:bdw
v2: Add LRI commands to set/reset bit that invalidates coherent lines,
update WA to include programming restrictions and exclude CHV as
it is not required (Ville)
v3: Avoid unnecessary read when it can be done by reading register once (Chris).
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Dave Gordon <david.s.gordon@intel.com>
Signed-off-by: Rafael Barbalho <rafael.barbalho@intel.com>
Signed-off-by: Arun Siluvery <arun.siluvery@linux.intel.com>
Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
In Indirect and Per context w/a batch buffer,
+WaDisableCtxRestoreArbitration
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Dave Gordon <david.s.gordon@intel.com>
Signed-off-by: Rafael Barbalho <rafael.barbalho@intel.com>
Signed-off-by: Arun Siluvery <arun.siluvery@linux.intel.com>
Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Some of the WA applied using WA batch buffers perform writes to scratch page.
In the current flow WA are initialized before scratch obj is allocated.
This patch reorders intel_init_pipe_control() to have a valid scratch obj
before we initialize WA.
v2: Check for valid scratch page before initializing WA as some of them
perform writes to it.
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Dave Gordon <david.s.gordon@intel.com>
Signed-off-by: Michel Thierry <michel.thierry@intel.com>
Signed-off-by: Arun Siluvery <arun.siluvery@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Some of the WA are to be applied during context save but before restore and
some at the end of context save/restore but before executing the instructions
in the ring, WA batch buffers are created for this purpose and these WA cannot
be applied using normal means. Each context has two registers to load the
offsets of these batch buffers. If they are non-zero, HW understands that it
need to execute these batches.
v1: In this version two separate ring_buffer objects were used to load WA
instructions for indirect and per context batch buffers and they were part
of every context.
v2: Chris suggested to include additional page in context and use it to load
these WA instead of creating separate objects. This will simplify lot of things
as we need not explicity pin/unpin them. Thomas Daniel further pointed that GuC
is planning to use a similar setup to share data between GuC and driver and
WA batch buffers can probably share that page. However after discussions with
Dave who is implementing GuC changes, he suggested to use an independent page
for the reasons - GuC area might grow and these WA are initialized only once and
are not changed afterwards so we can share them share across all contexts.
The page is updated with WA during render ring init. This has an advantage of
not adding more special cases to default_context.
We don't know upfront the number of WA we will applying using these batch buffers.
For this reason the size was fixed earlier but it is not a good idea. To fix this,
the functions that load instructions are modified to report the no of commands
inserted and the size is now calculated after the batch is updated. A macro is
introduced to add commands to these batch buffers which also checks for overflow
and returns error.
We have a full page dedicated for these WA so that should be sufficient for
good number of WA, anything more means we have major issues.
The list for Gen8 is small, same for Gen9 also, maybe few more gets added
going forward but not close to filling entire page. Chris suggested a two-pass
approach but we agreed to go with single page setup as it is a one-off routine
and simpler code wins.
One additional option is offset field which is helpful if we would like to
have multiple batches at different offsets within the page and select them
based on some criteria. This is not a requirement at this point but could
help in future (Dave).
Chris provided some helpful macros and suggestions which further simplified
the code, they will also help in reducing code duplication when WA for
other Gen are added. Add detailed comments explaining restrictions.
Use do {} while(0) for wa_ctx_emit() macro.
(Many thanks to Chris, Dave and Thomas for their reviews and inputs)
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Dave Gordon <david.s.gordon@intel.com>
Signed-off-by: Rafael Barbalho <rafael.barbalho@intel.com>
Signed-off-by: Arun Siluvery <arun.siluvery@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
After GPU reset, HW is losing the address of HWS page in the register.
The page itself is valid except that HW is not aware of its location.
[ 64.368623] [drm:gen8_init_common_ring [i915]] *ERROR* HWS Page address = 0x00000000
[ 64.368655] [drm:gen8_init_common_ring [i915]] *ERROR* HWS Page address = 0x00000000
[ 64.368681] [drm:gen8_init_common_ring [i915]] *ERROR* HWS Page address = 0x00000000
[ 64.368704] [drm:gen8_init_common_ring [i915]] *ERROR* HWS Page address = 0x00000000
This patch reloads this value into the register during ring init.
Signed-off-by: Arun Siluvery <arun.siluvery@linux.intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
commit 53292cdb06 ("drm/i915: Workaround
to avoid lite restore with HEAD==TAIL") added a check for req0 != null
which is unnecessary.
The only way req0 could be null is if the list was empty, and this is
already addressed at the beginning of execlists_context_unqueue().
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Michel Thierry <michel.thierry@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This trims a little overhead from the common case of not needing to
synchronize between rings.
v2: execlists is special and likes to duplicate code.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Currently, we only track the last request globally across all engines.
This prevents us from issuing concurrent read requests on e.g. the RCS
and BCS engines (or more likely the render and media engines). Without
semaphores, we incur costly stalls as we synchronise between rings -
greatly impacting the current performance of Broadwell versus Haswell in
certain workloads (like video decode). With the introduction of
reference counted requests, it is much easier to track the last request
per ring, as well as the last global write request so that we can
optimise inter-engine read read requests (as well as better optimise
certain CPU waits).
v2: Fix inverted readonly condition for nonblocking waits.
v3: Handle non-continguous engine array after waits
v4: Rebase, tidy, rewrite ring list debugging
v5: Use obj->active as a bitfield, it looks cool
v6: Micro-optimise, mostly involving moving code around
v7: Fix retire-requests-upto for execlists (and multiple rq->ringbuf)
v8: Rebase
v9: Refactor i915_gem_object_sync() to allow the compiler to better
optimise it.
Benchmark: igt/gem_read_read_speed
hsw:gt3e (with semaphores):
Before: Time to read-read 1024k: 275.794µs
After: Time to read-read 1024k: 123.260µs
hsw:gt3e (w/o semaphores):
Before: Time to read-read 1024k: 230.433µs
After: Time to read-read 1024k: 124.593µs
bdw-u (w/o semaphores): Before After
Time to read-read 1x1: 26.274µs 10.350µs
Time to read-read 128x128: 40.097µs 21.366µs
Time to read-read 256x256: 77.087µs 42.608µs
Time to read-read 512x512: 281.999µs 181.155µs
Time to read-read 1024x1024: 1196.141µs 1118.223µs
Time to read-read 2048x2048: 5639.072µs 5225.837µs
Time to read-read 4096x4096: 22401.662µs 21137.067µs
Time to read-read 8192x8192: 89617.735µs 85637.681µs
Testcase: igt/gem_concurrent_blit (read-read and friends)
Cc: Lionel Landwerlin <lionel.g.landwerlin@linux.intel.com>
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> [v8]
[danvet: s/\<rq\>/req/g]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
If an batch ends while the IRQs are not turned on the notification can
go missing and the GPU can hang. So generate a warning in this case.
Signed-off-by: Peter Antoine <peter.antoine@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
We switched from calling i915_gem_alloc_context_obj() to calling
i915_gem_alloc_object() so the error handling needs to be updated to
check for NULL instead of IS_ERR().
Fixes: 149c86e74f ('drm/i915: Allocate context objects from stolen')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
drm-intel-next-2015-04-23:
- dither support for ns2501 dvo (Thomas Richter)
- some polish for the gtt code and fixes to finally enable the cmd parser on hsw
- first pile of bxt stage 1 enabling (too many different people to list ...)
- more psr fixes from Rodrigo
- skl rotation support from Chandra
- more atomic work from Ander and Matt
- pile of cleanups and micro-ops for execlist from Chris
drm-intel-next-2015-04-10:
- cdclk handling cleanup and fixes from Ville
- more prep patches for olr removal from John Harrison
- gmbus pin naming rework from Jani (prep for bxt)
- remove ->new_config from Ander (more atomic conversion work)
- rps (boost) tuning and unification with byt/bsw from Chris
- cmd parser batch bool tuning from Chris
- gen8 dynamic pte allocation (Michel Thierry, based on work from Ben Widawsky)
- execlist tuning (not yet all of it) from Chris
- add drm_plane_from_index (Chandra)
- various small things all over
* tag 'drm-intel-next-2015-04-23-fixed' of git://anongit.freedesktop.org/drm-intel: (204 commits)
drm/i915/gtt: Allocate va range only if vma is not bound
drm/i915: Enable cmd parser to do secure batch promotion for aliasing ppgtt
drm/i915: fix intel_prepare_ddi
drm/i915: factor out ddi_get_encoder_port
drm/i915/hdmi: check port in ibx_infoframe_enabled
drm/i915/hdmi: fix vlv infoframe port check
drm/i915: Silence compiler warning in dvo
drm/i915: Update DRIVER_DATE to 20150423
drm/i915: Enable dithering on NatSemi DVO2501 for Fujitsu S6010
rm/i915: Move i915_get_ggtt_vma_pages into ggtt_bind_vma
drm/i915: Don't try to outsmart gcc in i915_gem_gtt.c
drm/i915: Unduplicate i915_ggtt_unbind/bind_vma
drm/i915: Move ppgtt_bind/unbind around
drm/i915: move i915_gem_restore_gtt_mappings around
drm/i915: Fix up the vma aliasing ppgtt binding
drm/i915: Remove misleading comment around bind_to_vm
drm/i915: Don't use atomics for pg_dirty_rings
drm/i915: Don't look at pg_dirty_rings for aliasing ppgtt
drm/i915/skl: Support Y tiling in MMIO flips
drm/i915: Fixup kerneldoc for struct intel_context
...
Conflicts:
drivers/gpu/drm/i915/i915_drv.c
WaIdleLiteRestore is an execlists-only workaround, and requires the driver
to ensure that any context always has HEAD!=TAIL when attempting lite
restore.
Add two extra MI_NOOP instructions at the end of each request, but keep
the requests tail pointing before the MI_NOOPs. We may not need to
executed them, and this is why request->tail is sampled before adding
these extra instructions.
If we submit a context to the ELSP which has previously been submitted,
move the tail pointer past the MI_NOOPs. This ensures HEAD!=TAIL.
v2: Move overallocation to gen8_emit_request, and added note about
sampling request->tail in commit message (Chris).
v3: Remove redundant request->tail assignment in __i915_add_request, in
lrc mode this is already set in execlists_context_queue.
Do not add wa implementation details inside gem (Chris).
v4: Apply the wa whenever the req has been resubmitted and update
comment (Chris).
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Thomas Daniel <thomas.daniel@intel.com>
Signed-off-by: Michel Thierry <michel.thierry@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Separate topic branch for bxt didn't work out since we needed to
refactor the gmbus code a bit to make it look decent. So backmerge.
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
On GEN9+ per specification a NULL PIPE_CONTROL needs to be emitted
before any PIPE_CONTROL command with the VS_INVALIDATE flag set.
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Nick Hoath <nicholas.hoath@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
After commit d7b9ca2f7a
("drm/i915: Remove request->uniq")
dev_priv is no longer needed.
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Michel Thierry <michel.thierry@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
As we never expose context objects directly to userspace, we can forgo
allocating a first-class GEM object for them and prefer to use the
limited resource of reserved/stolen memory for them. Note this means
that their initial contents are undefined.
However, a downside of using stolen objects for execlists is that we
cannot access the physical address directly (thanks MCH!) which prevents
their use.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
We already assign a unique identifier to every request: seqno. That
someone felt like adding a second one without even mentioning why and
tweaking ABI smells very fishy.
Fixes regression from
commit b3a38998f0
Author: Nick Hoath <nicholas.hoath@intel.com>
Date: Thu Feb 19 16:30:47 2015 +0000
drm/i915: Fix a use after free, and unbalanced refcounting
v2: Rebase
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Nick Hoath <nicholas.hoath@intel.com>
Cc: Thomas Daniel <thomas.daniel@intel.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Jani Nikula <jani.nikula@intel.com>
[danvet: Fixup because different merge order.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This eliminates six needless spin lock/unlock pairs when writing out
ELSP.
v2: Respin with my preferred colour.
v3: Mostly back to the original colour
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> [v1]
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
After the removal of DRI1, all access to the rings are through requests
and so we can always be sure that there is a request to wait upon to
free up available space. The fallback code only existed so that we could
quiesce the GPU following unmediated access by DRI1.
v2: Rebase
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
When we submit a request to the GPU, we first take the rpm wakelock, and
only release it once the GPU has been idle for a small period of time
after all requests have been complete. This means that we are sure no
new interrupt can arrive whilst we do not hold the rpm wakelock and so
can drop the individual get/put around every single request inside
execlists.
Note: to close one potential issue we should mark the GPU as busy
earlier in __i915_add_request.
To elaborate: The issue is that we emit the irq signalling sequence
before we grab the rpm reference, which means we could miss the
resulting interrupt (since that's not set up when suspended). The only
bad side effect is a missed interrupt, gt mmio writes automatically
wake up the hw itself. But otoh we have an umbrella rpm reference for
the entirety of execbuf, as long as that's there we're covered.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
[danvet: Explain a bit more about the add_request issue, which after
some irc chatting with Chris turns out to not be an issue really.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
We can use the simpler spinlock form to disable interrupts as we are
always outside of an irq/softirq handler.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This finishes off the dynamic page tables allocations, in the legacy 3
level style that already exists. Most everything has already been setup
to this point, the patch finishes off the enabling by setting the
appropriate function pointers.
In LRC mode, contexts need to know the PDPs when they are populated. With
dynamic page table allocations, these PDPs may not exist yet. Check if
PDPs have been allocated and use the scratch page if they do not exist yet.
Before submission, update the PDPs in the logic ring context as PDPs
have been allocated.
v2: Update aliasing/true ppgtt allocate/teardown/clear functions for
gen 6 & 7.
v3: Rebase.
v4: Remove BUG() from ppgtt_unbind_vma, but keep checking that either
teardown_va_range or clear_range functions exist (Daniel).
v5: Similar to gen6, in init, gen8_ppgtt_clear_range call is only needed
for aliasing ppgtt. Zombie tracking was originally added for teardown
function and is no longer required.
v6: Update err_out case in gen8_alloc_va_range (missed from lastest
rebase).
v7: Rebase after s/page_tables/page_table/.
v8: Updated scratch_pt check after scratch flag was removed in previous
patch.
v9: Note that lrc mode needs to be updated to support init state without
any PDP.
v10: Unmap correct page_table in gen8_alloc_va_range's error case, clean-up
gen8_aliasing_ppgtt_init (remove duplicated map), and initialize PTs
during page table allocation.
v11: Squashed LRC enabling commit, otherwise LRC mode would be left broken
until it was updated to handle the init case without any PDP.
v12: Do not overallocate new_pts bitmap, make alloc_gen8_temp_bitmaps
static and don't abuse of inline functions. (Mika)
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Michel Thierry <michel.thierry@intel.com> (v2+)
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
When we do dynamic page table allocations for gen8, we'll need to have
more control over how and when we map page tables, similar to gen6.
In particular, DMA mappings for page directories/tables occur at allocation
time.
This patch adds the functionality and calls it at init, which should
have no functional change.
The PDPEs are still a special case for now. We'll need a function for
that in the future as well.
v2: Handle renamed unmap_and_free_page functions.
v3: Updated after teardown_va logic was removed.
v4: Rebase after s/page_tables/page_table/.
v5: No longer allocate all PDPs in GEN8+ systems with less than 4GB of
memory, and update populate_lr_context to handle this new case (proper
tracking will be added later in the patch series).
v6: Assign lrc page directory pointer addresses using a macro. (Mika)
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Michel Thierry <michel.thierry@intel.com> (v2+)
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
I woke up one morning and found 50k objects sitting in the batch pool
and every search seemed to iterate the entire list... Painting the
screen in oils would provide a more fluid display.
One issue with the current design is that we only check for retirements
on the current ring when preparing to submit a new batch. This means
that we can have thousands of "active" batches on another ring that we
have to walk over. The simplest way to avoid that is to split the pools
per ring and then our LRU execution ordering will also ensure that the
inactive buffers remain at the front.
v2: execlists still requires duplicate code.
v3: execlists requires more duplicate code
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
According to Spec this is a reserved bit for Gen9+ and should not be set.
Change-Id: I0215fb7057b94139b7a2f90ecc7a0201c0c93ad4
Signed-off-by: Arun Siluvery <arun.siluvery@linux.intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The legacy and LRC code paths have an almost identical procedure for waiting for
space in the ring buffer. They both search for a request in the free list that
will advance the tail to a point where sufficient space is available. They then
wait for that request, retire it and recalculate the free space value.
Unfortunately, a bug in the LRC side meant that the resulting free space might
not be as large as expected and indeed, might not be sufficient. This is because
it was testing against the value of request->tail not request->postfix. Whereas,
when a request is retired, ringbuf->tail is updated to req->postfix not
req->tail.
Another significant difference between the two is that the LRC one did not trust
the wait for request to work! It redid the is there enough space available test
and would fail the call if insufficient. Whereas, the legacy version just said
'return 0' - it assumed the preceeding code works. This difference meant that
the LRC version still worked even with the bug - it just fell back to the
polling wait path.
For: VIZ-5115
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Reviewed-by: Thomas Daniel <thomas.daniel@intel.com>
Reviewed-by: Tomas Elf <tomas.elf@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The request allocation code is largely duplicated between legacy mode and
execlist mode. The actual difference between the two versions of the code is
pretty minimal.
This patch moves the common code out into a separate function. This is then
called by the execution specific version prior to setting up the one different
value.
For: VIZ-5190
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Reviewed-by: Tomas Elf <tomas.elf@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The only usage of intel_logical_ring_begin() is within intel_lrc.c so it can be
made static. To avoid a forward declaration at the top of the file, it and bunch
of other functions have been shuffled upwards.
For: VIZ-5115
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Reviewed-by: Tomas Elf <tomas.elf@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
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Merge tag 'v4.0-rc3' into drm-next
Linux 4.0-rc3 backmerge to fix two i915 conflicts, and get
some mainline bug fixes needed for my testing box
Conflicts:
drivers/gpu/drm/i915/i915_drv.h
drivers/gpu/drm/i915/intel_display.c
- Y tiling support for scanout from Tvrtko&Damien
- Remove more UMS support
- some small prep patches for OLR removal from John Harrison
- first few patches for dynamic pagetable allocation from Ben Widawsky, rebased
by tons of other people
- DRRS support patches (Sonika&Vandana)
- fbc patches from Paulo
- make sure our vblank callbacks aren't called when the pipes are off
- various patches all over
* tag 'drm-intel-next-2015-02-27' of git://anongit.freedesktop.org/drm-intel: (61 commits)
drm/i915: Update DRIVER_DATE to 20150227
drm/i915: Clarify obj->map_and_fenceable
drm/i915/skl: Allow Y (and Yf) frame buffer creation
drm/i915/skl: Update watermarks for Y tiling
drm/i915/skl: Updated watermark programming
drm/i915/skl: Adjust get_plane_config() to support Yb/Yf tiling
drm/i915/skl: Teach pin_and_fence_fb_obj() about Y tiling constraints
drm/i915/skl: Adjust intel_fb_align_height() for Yb/Yf tiling
drm/i915/skl: Allow scanning out Y and Yf fbs
drm/i915/skl: Add new displayable tiling formats
drm/i915: Remove DRIVER_MODESET checks from modeset code
drm/i915: Remove regfile code&data for UMS suspend/resume
drm/i915: Remove DRIVER_MODESET checks from gem code
drm/i915: Remove DRIVER_MODESET checks in the gpu reset code
drm/i915: Remove DRIVER_MODESET checks from suspend/resume code
drm/i915: Remove DRIVER_MODESET checks in load/unload/close code
drm/i915: fix a printk format
drm/i915: Add media rc6 residency file to sysfs
drm/i915: Add missing description to parameter in alloc_pt_range
drm/i915: Removed the read of RP_STATE_CAP from sysfs/debugfs functions
...
- use the atomic helpers for plane_upate/disable hooks (Matt Roper)
- refactor the initial plane config code (Damien)
- ppgtt prep patches for dynamic pagetable alloc (Ben Widawsky, reworked and
rebased by a lot of other people)
- framebuffer modifier support from Tvrtko Ursulin, drm core code from Rob Clark
- piles of workaround patches for skl from Damien and Nick Hoath
- vGPU support for xengt on the client side (Yu Zhang)
- and the usual smaller things all over
* tag 'drm-intel-next-2015-02-14' of git://anongit.freedesktop.org/drm-intel: (88 commits)
drm/i915: Update DRIVER_DATE to 20150214
drm/i915: Remove references to previously removed UMS config option
drm/i915/skl: Use a LRI for WaDisableDgMirrorFixInHalfSliceChicken5
drm/i915/skl: Fix always true comparison in a revision id check
drm/i915/skl: Implement WaEnableLbsSlaRetryTimerDecrement
drm/i915/skl: Implement WaSetDisablePixMaskCammingAndRhwoInCommonSliceChicken
drm/i915: Add process identifier to requests
drm/i915/skl: Implement WaBarrierPerformanceFixDisable
drm/i915/skl: Implement WaCcsTlbPrefetchDisable:skl
drm/i915/skl: Implement WaDisableChickenBitTSGBarrierAckForFFSliceCS
drm/i915/skl: Implement WaDisableHDCInvalidation
drm/i915/skl: Implement WaDisableLSQCROPERFforOCL
drm/i915/skl: Implement WaDisablePartialResolveInVc
drm/i915/skl: Introduce a SKL specific init_workarounds()
drm/i915/skl: Document that we implement WaRsClearFWBitsAtReset
drm/i915/skl: Implement WaSetGAPSunitClckGateDisable
drm/i915/skl: Make the init clock gating function skylake specific
drm/i915/skl: Provide a gen9 specific init_render_ring()
drm/i915/skl: Document the WM read latency W/A with its name
drm/i915/skl: Also detect eDRAM on SKL
...
In execlist mode, the ringbuf is a function of the ring and context whereas in
legacy mode, it is derived from the ring alone. Thus the calculation required to
determine the ringbuf pointer from the ring (and context) also needs to test
execlist mode or not. This is messy.
Further, the request structure holds a pointer to both the ring and the context
for which it was created. Thus, given a request, it is possible to derive the
ringbuf in either legacy or execlist mode. Hence it is necessary to pass just
the request in to all the low level functions rather than some combination of
request, ring, context and ringbuf. However, rather than recalculating it each
time, it is much simpler to just cache the ringbuf pointer in the request
structure itself.
Caching the pointer means the calculation is done once at request creation time
and all further code and simply read it directly from the request structure.
OTC-Jira: VIZ-5115
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
[danvet: Drop contentless comment in lrc alloc request entirely. And
spelling fix in the commit message.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
There is a trace point in the legacy execbuffer execution path that is missing
from the execlist path. Trace points are extremely useful for debugging and are
used by various automated validation tests. Hence, this patch adds the missing
trace point back in.
OTC-Jira: VIZ-5115
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
There is a flags word that is passed through the execbuffer code path all the
way from initial decoding of the user parameters down to the very final dispatch
buffer call. It is simply called 'flags'. Unfortuantely, there are many other
flags words floating around in the same blocks of code. Even more once the GPU
scheduler arrives.
This patch makes it more obvious exactly which flags word is which by renaming
'flags' to 'dispatch_flags'. Note that the bit definitions for this flags word
already have an 'I915_DISPATCH_' prefix on them and so are not quite so
ambiguous.
OTC-Jira: VIZ-1587
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
[danvet: Resolve conflict with Chris' rework of the bb parsing.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
As we move toward dynamic page table allocation, it becomes much easier
to manage our data structures if break do things less coarsely by
breaking up all of our actions into individual tasks. This makes the
code easier to write, read, and verify.
Aside from the dissection of the allocation functions, the patch
statically allocates the page table structures without a page directory.
This remains the same for all platforms,
The patch itself should not have much functional difference. The primary
noticeable difference is the fact that page tables are no longer
allocated, but rather statically declared as part of the page directory.
This has non-zero overhead, but things gain additional complexity as a
result.
This patch exists for a few reasons:
1. Splitting out the functions allows easily combining GEN6 and GEN8
code. Page tables have no difference based on GEN8. As we'll see in a
future patch when we add the DMA mappings to the allocations, it
requires only one small change to make work, and error handling should
just fall into place.
2. Unless we always want to allocate all page tables under a given PDE,
we'll have to eventually break this up into an array of pointers (or
pointer to pointer).
3. Having the discrete functions is easier to review, and understand.
All allocations and frees now take place in just a couple of locations.
Reviewing, and catching leaks should be easy.
4. Less important: the GFP flags are confined to one location, which
makes playing around with such things trivial.
v2: Updated commit message to explain why this patch exists
v3: For lrc, s/pdp.page_directory[i].daddr/pdp.page_directory[i]->daddr/
v4: Renamed free_pt/pd_single functions to unmap_and_free_pt/pd (Daniel)
v5: Added additional safety checks in gen8 clear/free/unmap.
v6: Use WARN_ON and return -EINVAL in alloc_pt_range (Mika).
v7: Make err_out loop symmetrical to the way we allocate in
alloc_pt_range. Also s/page_tables/page_table and correct commit
message (Mika)
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Michel Thierry <michel.thierry@intel.com> (v3+)
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Move the remaining members over to the new page table structures.
This can be squashed with the previous commit if desire. The reasoning
is the same as that patch. I simply felt it is easier to review if split.
v2: In lrc: s/ppgtt->pd_dma_addr[i]/ppgtt->pdp.page_directory[i].daddr/
v3: Rebase.
v4: Rebased after s/page_tables/page_table/.
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Michel Thierry <michel.thierry@intel.com> (v2+)
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
When converting from implicitly tracked execlist queue items to ref counted
requests, not all frees of requests were replaced with unrefs, and extraneous
refs/unrefs of contexts were added.
Correct the unbalanced refcount & replace the frees.
Remove a noisy warning when hitting the request creation path.
drm_i915_gem_request and intel_context are both kref reference counted
structures. Upon allocation, drm_i915_gem_request's ref count should be
bumped using kref_init. When a context is assigned to the request,
the context's reference count should be bumped using i915_gem_context_reference.
i915_gem_request_reference will reduce the context reference count when
the request is freed.
Problem introduced in
commit 6d3d8274bc
Author: Nick Hoath <nicholas.hoath@intel.com>
AuthorDate: Thu Jan 15 13:10:39 2015 +0000
drm/i915: Subsume intel_ctx_submit_request in to drm_i915_gem_request
v2: Added comments explaining how the ctx pointer and the request object should
be ref-counted. Removed noisy warning.
v3: Cleaned up the language used in the commit & the header
description (Thanks David Gordon)
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=88652
Signed-off-by: Nick Hoath <nicholas.hoath@intel.com>
Reviewed-by: Thomas Daniel <thomas.daniel@intel.com>
Reviewed-by: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Work was getting left behind in LRC contexts during reset. This causes a hang
if the GPU is reset when HEAD==TAIL because the context's ringbuffer head and
tail don't get reset and retiring a request doesn't alter them, so the ring
still appears full.
Added a function intel_lr_context_reset() to reset head and tail on a LRC and
its ringbuffer.
Call intel_lr_context_reset() for each context in i915_gem_context_reset() when
in execlists mode.
Testcase: igt/pm_rps --run-subtest reset #bdw
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=88096
Signed-off-by: Thomas Daniel <thomas.daniel@intel.com>
Reviewed-by: Dave Gordon <david.s.gordon@intel.com>
[danvet: Flatten control flow in the lrc reset code a notch.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
On Gen9 the render power gating can leave slice/subslice/EU in
a partially enabled state. We must make an explicit request for
full SSEU enablement through the Render Power Clock State
register when resuming render work. This register is save/
restored in the logical ring context image for execlist
submission mode. Initialize its value in each LRC image to
request full enablement according to the device SSEU config.
Thanks to Sharma Ankitprasad and Akash Goel for highlighting the
issue and proposing the initial fix on which this patch is based.
v2: Adjusted the names of the power gating support flags to fit
update of an earlier patch.
Signed-off-by: Jeff McGee <jeff.mcgee@intel.com>
Reviewed-by: "Akash Goel <akash.goel@intel.com>"
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
WaDisableAsyncFlipPerfMode isn't listed for SKL and
INSTPM_FORCE_ORDERING is MBZ so let's make a gen9 specific render init
function.
Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Reviewed-by: Nick Hoath <nicholas.hoath@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This function is only used in intel_lrc.c, so restrict it to that file. The
function was moved around to avoid a forward declaration and group it with its
user.
Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This function is only used in intel_lrc.c, so restrict it to that file. The
function was moved around to avoid a forward declaration and group it with its
user.
Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This patch introduces 2 bit definitions of context save/restore
control register.
Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
Suggested-by: Dave Gordon <david.s.gordon@intel.com>
Cc: Dave Gordon <david.s.gordon@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This looked like an odd regression from
commit ec5cc0f9b0
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date: Thu Jun 12 10:28:55 2014 +0100
drm/i915: Restrict GPU boost to the RCS engine
but in reality it undercovered a much older coherency bug. The issue that
boosting the GPU frequency on the BCS ring was masking was that we could
wake the CPU up after completion of a BCS batch and inspect memory prior
to the write cache being fully evicted. In order to serialise the
breadcrumb interrupt (and so ensure that the CPU's view of memory is
coherent) we need to perform a post-sync operation in the MI_FLUSH_DW.
v2: Fix all the MI_FLUSH_DW (bsd plus the duplication in execlists).
Also fix the invalidate_domains mask in gen8_emit_flush() for ring !=
VCS.
Testcase: gpuX-rcs-gpu-read-after-write
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: stable@vger.kernel.org
Acked-by: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Remove request from list before unreferencing it, in case it's actually
the only reference. (Found by Tvrtko Ursulin)
This issue has been most likely introduced in
commit 6d3d8274bc
Author: Nick Hoath <nicholas.hoath@intel.com>
Date: Thu Jan 15 13:10:39 2015 +0000
drm/i915: Subsume intel_ctx_submit_request in to drm_i915_gem_request
Signed-off-by: Nick Hoath <nicholas.hoath@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
We increase it when we pin, so for the casual reader
rename it to cause less confusion.
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Thomas Daniel <thomas.daniel@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
We pin when we submit to execlist queue. Balance
the pinning when the submitted queue is cleaned on reset.
Cc: Dave Gordon <david.s.gordon@intel.com>
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Thomas Daniel <thomas.daniel@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
We have multiple forcewake domains now on recent gens. Change the
function naming to reflect this.
v2: More verbose names (Chris)
v3: Rebase
v4: Rebase
v5: Add documentation for forcewake_get/put
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Deepak S <deepak.s@linux.intel.com> (v2)
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
On user forcewake access, assert that runtime pm reference is held.
Fix and cleanup the callsites accordingly.
v2: Remove intel_runtime_pm_get() rebasehap (Deepak)
v3: use drivers own runtime state tracking as pm_runtime_active()
will return wrong results when we are in resume callchain (Mika)
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Deepak S <deepak.s@linux.intel.com> (v2)
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Move all remaining elements that were unique to execlists queue items
in to the associated request.
Issue: VIZ-4274
v2: Rebase. Fixed issue of overzealous freeing of request.
v3: Removed re-addition of cleanup work queue (found by Daniel Vetter)
v4: Rebase.
v5: Actual removal of intel_ctx_submit_request. Update both tail and postfix
pointer in __i915_add_request (found by Thomas Daniel)
v6: Removed unrelated changes
Signed-off-by: Nick Hoath <nicholas.hoath@intel.com>
Reviewed-by: Thomas Daniel <thomas.daniel@intel.com>
[danvet: Reformat comment with strange linebreaks.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The first pass implementation of execlists required a backpointer to the context to be held
in the intel_ringbuffer. However the context pointer is available higher in the call stack.
Remove the backpointer from the ring buffer structure and instead pass it down through the
call stack.
v2: Integrate this changeset with the removal of duplicate request/execlist queue item members.
v3: Rebase
v4: Rebase. Remove passing of context when the request is passed.
Signed-off-by: Nick Hoath <nicholas.hoath@intel.com>
Reviewed-by: Thomas Daniel <thomas.daniel@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Where there were duplicate variables for the tail, context and ring (engine)
in the gem request and the execlist queue item, use the one from the request
and remove the duplicate from the execlist queue item.
Issue: VIZ-4274
v1: Rebase
v2: Fixed build issues. Keep separate postfix & tail pointers as these are
used in different ways. Reinserted missing full tail pointer update.
Signed-off-by: Nick Hoath <nicholas.hoath@intel.com>
Reviewed-by: Thomas Daniel <thomas.daniel@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Add a reference and pointer from the execlist queue item to the associated
gem request. For execlist requests that don't have a request, create one
as a placeholder.
Issue: VIZ-4274
v1: Rebase after upstream of "Replace seqno values with request structures" patchset.
Signed-off-by: Nick Hoath <nicholas.hoath@intel.com>
Reviewed-by: Thomas Daniel <thomas.daniel@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
A previous commit enabled execlists by default:
commit 27401d126b ("drm/i915/bdw: Enable execlists by default where supported")
This allowed routine testing of execlists which exposed a regression when
resuming from suspend. The cause was tracked down the to recent changes to the
ring init sequence:
commit 35a57ffbb1 ("drm/i915: Only init engines once")
During a suspend/resume cycle the hardware Context Status Buffer write pointer
is reset. However since the recent changes to the init sequence the software CSB
read pointer is no longer reset. This means that context status events are not
handled correctly and new contexts are not written to the ELSP, resulting in an
apparent GPU hang.
Pending further changes to the ring init code, just move the
ring->next_context_status_buffer initialization into gen8_init_common_ring to
fix this regression.
v2: Moved init into gen8_init_common_ring rather than context_enable after
feedback from Daniel Vetter. Updated commit msg to reflect this and also cite
commits related to the regression. Fixed bz link to correct bug.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=88096
Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Dave Gordon <david.s.gordon@intel.com>
Signed-off-by: Thomas Daniel <thomas.daniel@intel.com>
Reviewed-by: Dave Gordon <david.s.gordon@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Otherwise, new platforms without workarounds will hit this warning for
every new context created.
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Michel Thierry <michel.thierry@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Execlist support in the i915 driver is now considered good enough for the
feature to be enabled by default on Gen8 and later and routinely tested.
Adjusted i915 parameters structure initialization to reflect this and updated
the comment in intel_sanitize_enable_execlists().
There's still work to do before we can let the wider massive onto it,
but there's still time left before the 3.20 cutoff.
v2: Update the MODULE_PARM_DESC too.
Issue: VIZ-2020
Signed-off-by: Thomas Daniel <thomas.daniel@intel.com>
[danvet: Add note that there's still some work left to do.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
We consistently use the _irq_handler postfix for functions called in
hardirq context. Especially when it's a non-static function hardirq is
a crazy enough calling context to warrant this level of ocd. So rename
it.
Cc: Thomas Daniel <thomas.daniel@intel.com>
Reviewed-by: Thomas Daniel <thomas.daniel@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
For debugging purposes, it is useful to be able to uniquely identify a given
request structure as it works its way through the system. This becomes
especially tricky once the seqno value is lazily allocated as then the request
has nothing but its pointer to identify it for much of its life.
Change-Id: Ie76b2268b940467f4cdf5a4ba6f5a54cbb96445d
For: VIZ-4377
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Reviewed-by: Thomas Daniel <Thomas.Daniel@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
There is a general theory that kzmalloc is better/safer than kmalloc, especially
for interesting data structures. This change updates the request structure
allocation to be zero filled.
This also fixes crashes in the reset code. Quoting Mika's patch:
"Clean the request structure on alloc. Otherwise we might end up
referencing uninitialized fields. This is apparent when we try to
cleanup the preallocated request on ring reset, before any request has
been submitted to the ring. The request->ctx is foobar and we end up
freeing the foobarness."
Note that this fixes a regression introduced in
commit 9eba5d4a1d
Author: John Harrison <John.C.Harrison@Intel.com>
Date: Mon Nov 24 18:49:23 2014 +0000
drm/i915: Ensure OLS & PLR are always in sync
References: https://bugs.freedesktop.org/show_bug.cgi?id=86959
References: https://bugs.freedesktop.org/show_bug.cgi?id=86962
References: https://bugs.freedesktop.org/show_bug.cgi?id=86992
Change-Id: I68715ef758025fab8db763941ef63bf60d7031e2
For: VIZ-4377
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Reviewed-by: Thomas Daniel <Thomas.Daniel@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
MI_STORE_DWORD_IMM length has been the same ever since gen4. Rename
the define to avoid potential confusion if someone tries to use this
on pre-gen8.
Also correct the comment on MI_MEM_VIRTUAL bit. It's present on 945,g33
and 965 only.
Cc: Oscar Mateo <oscar.mateo@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
[danvet: Add USE_GGTT define for g4x+ too.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
A previous commit introduced engine init changes:
commit 372ee59699d9 ("drm/i915: Only init engines once")
This broke execlists as intel_lr_context_render_state_init was trying to emit
commands to the RCS for the default context before the ring->init_hw was called.
Made a new gen8_init_rcs_context function and assign in to render ring
init_context. Moved call to intel_logical_ring_workarounds_emit into
gen8_init_rcs_context to maintain previous functionality.
Moved call to render_state_init from lr_context_deferred_create into
gen8_init_rcs_context, and modified deferred_create to call ring->init_context
for non-default contexts.
Modified i915_gem_context_enable to call ring->init_context for the default
context.
So init_context will now always be called when the hw is ready - in
i915_gem_context_enable for the default context and in lr_context_deferred_create
for other contexts.
Signed-off-by: Thomas Daniel <thomas.daniel@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Now that sanity prevails and we have the clean split between software
init and starting the engines we can drop all the "have we allocate
this struct already?" nonsense.
Execlist code could benefit quite a bit more still, but that's for
another patch.
Reviewed-by: Dave Gordon <david.s.gordon@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
We can do this.
And now there's finally the clean split between software setup and
hardware setup I kinda wanted since multi-ring support was merged
aeons ago. It only took almost 5 years.
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Reviewed-by: Dave Gordon <david.s.gordon@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
With this all the ->init_hw hooks really only set up hw state needed
to start the ring, all the software state setup and memory/buffer
allocations happen beforehand.
v2: We need to call intel_init_pipe_control after the ring init since
otherwise engine->dev is NULL and it falls over. Currently that's
now after the hw ring is enabled but a) we'll be fine as long as no
one submits a batch b) this will change soon.
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Reviewed-by: Dave Gordon <david.s.gordon@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This is (mostly, some exceptions that need fixing) the hw setup
function which starts the ring. And not the function which allocates
all the resources.
Make this clear by giving it a better name.
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Reviewed-by: Dave Gordon <david.s.gordon@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
There are numerous places in the code where the driver's idea of
how much space is left in a ring is updated using the driver's
latest notions of the positions of 'head' and 'tail' for the ring.
Among them are some that update one or both of these values before
(re)doing the calculation. In particular, there are four different
places in the code where 'last_retired_head' is copied to 'head'
and then set to -1; and two of these do not have a guard to check
that it has actually been updated since last time it was consumed,
leaving the possibility that the dummy -1 can be transferred from
'last_retired_head' to 'head', causing the space calculation to
produce 'impossible' results (previously seen on Android/VLV).
This code therefore consolidates all the calculation and updating of
these values, such that there is only one place where the ring space
is updated, and it ALWAYS uses (and consumes) 'last_retired_head' if
(and ONLY if) it has been updated since the last call.
Signed-off-by: Dave Gordon <david.s.gordon@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
It makes a lot more sense (and makes future seqno -> request conversion patches
simpler) to fill in the 'ring' field of the request structure at the point of
creation rather than submission. Given that the request structure is assigned by
ring specific code and thus is locked to a ring from the start, there really is
no reason to defer this assignment.
For: VIZ-4377
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Reviewed-by: Thomas Daniel <Thomas.Daniel@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
There is no longer any need to retrieve a seqno value from an i915_add_request()
call. The calling code already knows which request structure is being processed
(it can only be ring->OLR). And as the request itself is now used in preference
to the basic seqno value, the latter is now redundant in this situation.
For: VIZ-4377
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Reviewed-by: Thomas Daniel <Thomas.Daniel@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Updated i915_wait_seqno() to take a request structure instead of a seqno value
and renamed it accordingly. Internally, it just pulls the seqno out of the
request and calls on to __wait_seqno() as before. However, all the code further
up the stack is now simplified as it can just pass the request object straight
through without having to peek inside.
For: VIZ-4377
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Reviewed-by: Thomas Daniel <Thomas.Daniel@intel.com>
[danvet: Squash in hunk from an earlier patch which was rebased
wrongly.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The OLS value is now obsolete. Exactly the same value is guarateed to be always
available as PLR->seqno. Thus it is safe to remove the OLS completely. And also
to rename the PLR to OLR to keep the 'outstanding lazy ...' naming convention
valid.
For: VIZ-4377
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Reviewed-by: Thomas Daniel <Thomas.Daniel@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The plan is to use request structures everywhere that seqno values were
previously used. This means saving pointers to structures in places that used to
be simple integers. In turn, that means that the target structure now needs much
more stringent lifetime tracking. That is, it must not be freed while some other
random object still holds a pointer to it.
To achieve this tracking, a reference count needs to be added. Whenever a
pointer to the structure is saved away, the count must be incremented and the
free must only occur when all references have been released.
For: VIZ-4377
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Reviewed-by: Thomas Daniel <Thomas.Daniel@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The aim is to replace seqno values with request structures. A step along the way
is to switch to using the PLR in preference to the OLS. That requires the PLR to
only be valid when and only when the OLS is also valid. I.e., the two must be
kept in lock step. Then, code which was using the OLS can be safely switched
over to using the PLR instead.
For: VIZ-4377
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Reviewed-by: Thomas Daniel <Thomas.Daniel@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The logical ring code was updating the software ring 'head' value
by reading the hardware 'HEAD' register. In LRC mode, this is not
valid as the hardware is not necessarily executing the same context
that is being processed by the software. Thus reading the h/w HEAD
could put an unrelated (undefined, effectively random) value into
the s/w 'head' -- A Bad Thing for the free space calculations.
Signed-off-by: Dave Gordon <david.s.gordon@intel.com>
Reviewed-by: Deepak S <deepak.s@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The request queue is per-engine, and may therefore contain requests
from several different contexts/ringbuffers. In determining which
request to wait for, this function should only consider requests
from the ringbuffer that it's checking for space, and ignore any
that it finds that belong to other contexts.
Signed-off-by: Dave Gordon <david.s.gordon@intel.com>
Reviewed-by: Deepak S <deepak.s@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Same as with the context, pinning to GGTT regardless is harmful (it
badly fragments the GGTT and can even exhaust it).
Unfortunately, this case is also more complex than the previous one
because we need to map and access the ringbuffer in several places
along the execbuffer path (and we cannot make do by leaving the
default ringbuffer pinned, as before). Also, the context object
itself contains a pointer to the ringbuffer address that we have to
keep updated if we are going to allow the ringbuffer to move around.
v2: Same as with the context pinning, we cannot really do it during
an interrupt. Also, pin the default ringbuffers objects regardless
(makes error capture a lot easier).
v3: Rebased. Take a pin reference of the ringbuffer for each item
in the execlist request queue because the hardware may still be using
the ringbuffer after the MI_USER_INTERRUPT to notify the seqno update
is executed. The ringbuffer must remain pinned until the context save
is complete. No longer pin and unpin ringbuffer in
populate_lr_context() - this transient address is meaningless and the
pinning can cause a sleep while atomic.
v4: Moved ringbuffer pin and unpin into the lr_context_pin functions.
Downgraded pinning check BUG_ONs to WARN_ONs.
v5: Reinstated WARN_ONs for unexpected execlist states. Removed unused
variable.
Issue: VIZ-4277
Signed-off-by: Oscar Mateo <oscar.mateo@intel.com>
Signed-off-by: Thomas Daniel <thomas.daniel@intel.com>
Reviewed-by: Akash Goel <akash.goels@gmail.com>
Reviewed-by: Deepak S<deepak.s@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Up until now, we have pinned every logical ring context backing object
during creation, and left it pinned until destruction. This made my life
easier, but it's a harmful thing to do, because we cause fragmentation
of the GGTT (and, eventually, we would run out of space).
This patch makes the pinning on-demand: the backing objects of the two
contexts that are written to the ELSP are pinned right before submission
and unpinned once the hardware is done with them. The only context that
is still pinned regardless is the global default one, so that the HWS can
still be accessed in the same way (ring->status_page).
v2: In the early version of this patch, we were pinning the context as
we put it into the ELSP: on the one hand, this is very efficient because
only a maximum two contexts are pinned at any given time, but on the other
hand, we cannot really pin in interrupt time :(
v3: Use a mutex rather than atomic_t to protect pin count to avoid races.
Do not unpin default context in free_request.
v4: Break out pin and unpin into functions. Fix style problems reported
by checkpatch
v5: Remove unpin_lock as all pinning and unpinning is done with the struct
mutex already locked. Add WARN_ONs to make sure this is the case in future.
Issue: VIZ-4277
Signed-off-by: Oscar Mateo <oscar.mateo@intel.com>
Signed-off-by: Thomas Daniel <thomas.daniel@intel.com>
Reviewed-by: Akash Goel <akash.goels@gmail.com>
Reviewed-by: Deepak S<deepak.s@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
No longer create a work item to clean each execlist queue item.
Instead, move retired execlist requests to a queue and clean up the
items during retire_requests.
v2: Fix legacy ring path broken during overzealous cleanup
v3: Update idle detection to take execlists queue into account
v4: Grab execlist lock when checking queue state
v5: Fix leaking requests by freeing in execlists_retire_requests.
Issue: VIZ-4274
Signed-off-by: Thomas Daniel <thomas.daniel@intel.com>
Reviewed-by: Deepak S <deepak.s@linux.intel.com>
Reviewed-by: Akash Goel <akash.goels@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
kmap never fails.
Spotted-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Arun Siluvery <arun.siluvery@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Running the driver without execlists and hence PPGTT (either aliasing or
full) isn't a supported configuration on gen9+.
Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Write and reads following the block changed use engine specific use counters
and unless that is matched here force wake use counting goes bad. Same
force wake is attempted to be taken twice which leads to at least time outs.
NOTE: Depending on feedback from hardware designers it may not be necessary
to grab force wakes on Gen9 here. But for Gen8 it is needed due to a race
between RC6 and ELSP writes.
v2: Added blitter force wake engine and made more future proof.
Added commit note.
Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The LRC increased in size on gen9. Make sure we return the right
size in get_lr_context_size()
v2. Corrected the size, should be 22 pages. I unintentionally mailed out
a test patch w/ size equaling 23 pages.
Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Michael H. Nguyen <michael.h.nguyen@intel.com>
Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Following the legacy ring submission example, update the
ring->init_context() hook to support the execlist submission mode.
v2: update to use the new workaround macros and cleanup unused code.
This takes care of both bdw and chv workarounds.
v2.1: Add missing call to init_context() during deferred context creation.
v3: Split init_context (emit) in legacy/lrc modes. For lrc, get the ringbuf
from the context (Mika/Daniel).
v4: Merge init_context interfaces back, the legacy mode only needs the ring,
but the lrc mode needs the ring and context (Mika).
Issue: VIZ-4092
Issue: GMIN-3475
Change-Id: Ie3d093b2542ab0e2a44b90460533e2f979788d6c
Cc: Deepak S <deepak.s@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Michel Thierry <michel.thierry@intel.com>
Signed-off-by: Arun Siluvery <arun.siluvery@linux.intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
[danvet: Align function paramater lists properly.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Backmerge drm-next so that I can keep merging patches. Specifically I
want:
- atomic stuff, yay!
- eld parsing patch from Jani.
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Write HWS_PGA address even in execlists mode as the global hardware status
page is still required. This address was previously uninitialized and
HWSP writes would clobber whatever buffer happened to reside at GGTT
address 0.
v2: Break out hardware status page setup into a separate function.
Issue: VIZ-2020
Signed-off-by: Thomas Daniel <thomas.daniel@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Just various stuff all over from a bunch of people. Shortlog gives a beter
overview, it's really all misc drm patches.
* tag 'topic/core-stuff-2014-11-05' of git://anongit.freedesktop.org/drm-intel:
drm/edid: add #defines and helpers for ELD
drm/dp: Add counters in the drm_dp_aux struct for I2C NACKs and DEFERs
drm: Remove compiler BUG_ON() test
drm: Fix DRM_FORCE_ON_DIGITAL use
drm/gma500: Don't destroy DRM properties in the driver
drm/i915: Don't destroy DRM properties in the driver
drm: Add a note to drm_property_create() about property lifetime
gpu: drm: Fix warning caused by a parameter description in drm_crtc.c
drm/dp-helper: Move the legacy helpers to gma500
drm/crtc: Remove duplicated ioctl code
drm/crtc: Fix two typos
gpu:drm: Fix typo in Documentation/DocBook/drm.xml
gpu: drm: drm_dp_mst_topology.c: Fix improper use of strncat
drm: drm_err: Remove unnecessary __func__ argument
drm: Implement O_NONBLOCK support on /dev/dri/cardN
execlists_submit_context() always returns 0, which is redundant.
And its name is inaccurate, since it actually submits (up to)
TWO contextS. So we rename it, change it to "void", and remove
the WARN_ON() testing its return value.
Change-Id: Ie225b0eca7754c6093c8b8bd15550b251b6feb82
Signed-off-by: Dave Gordon <david.s.gordon@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
If a ring failed to initialise for any reason then the error path would try to
clean up all rings including those that had not yet been allocated. The ring
clean up code did a check that the ring was valid before starting its work.
Unfortunately, that was after it had already dereferenced the ring to obtain a
dev_private pointer.
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This patch fix spelling typos found in drm.xml.
It is because the file is generated from comments in
source codes, I have to fix the typos within source files.
Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Yet another place that wasn't properly transformed when implementing
SOix. While at it convert the checks to WARN_ON on gen5+ (since we
don't have UMS potentially doing stupid things on those platforms).
And also add the corresponding checks to the put functions (again with
a WARN_ON) for gen5+.
v2: Drop the WARNINGS in the irq_put functions (including the existing
one for vebox), Chris convinced me that they're not that terribly
useful.
v3: Don't forget about execlist code.
Cc: Imre Deak <imre.deak@intel.com>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: "Volkin, Bradley D" <bradley.d.volkin@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
In chv, we have two power wells Render & Media. We need to use
corresponsing forcewake count. If we dont follow this we are getting
error "*ERROR*: Timed out waiting for forcewake old ack to clear" due to
multiple entry into __vlv_force_wake_get.
Signed-off-by: Deepak S <deepak.s@linux.intel.com>
Requested-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The batchbuffer that sets the render context state is submitted
in a different way, and from different places.
We needed to make both the render state preparation and free functions
outside accesible, and namespace accordingly. This mess is so that all
LR, LRC and Execlists functionality can go together in intel_lrc.c: we
can fix all of this later on, once the interfaces are clear.
v2: Create a separate ctx->rcs_initialized for the Execlists case, as
suggested by Chris Wilson.
Signed-off-by: Oscar Mateo <oscar.mateo@intel.com>
v3: Setup ring status page in lr_context_deferred_create when the
default context is being created. This means that the render state
init for the default context is no longer a special case. Execute
deferred creation of the default context at the end of
logical_ring_init to allow the render state commands to be submitted.
Fix style errors reported by checkpatch. Rebased.
Signed-off-by: Thomas Daniel <thomas.daniel@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
John Harrison