Commit Graph

334 Commits

Author SHA1 Message Date
Tvrtko Ursulin fe14d5f4e5 drm/i915: Infrastructure for supporting different GGTT views per object
Things like reliable GGTT mappings and mirrored 2d-on-3d display will need
to map objects into the same address space multiple times.

Added a GGTT view concept and linked it with the VMA to distinguish between
multiple instances per address space.

New objects and GEM functions which do not take this new view as a parameter
assume the default of zero (I915_GGTT_VIEW_NORMAL) which preserves the
previous behaviour.

This now means that objects can have multiple VMA entries so the code which
assumed there will only be one also had to be modified.

Alternative GGTT views are supposed to borrow DMA addresses from obj->pages
which is DMA mapped on first VMA instantiation and unmapped on the last one
going away.

v2:
    * Removed per view special casing in i915_gem_ggtt_prepare /
      finish_object in favour of creating and destroying DMA mappings
      on first VMA instantiation and last VMA destruction. (Daniel Vetter)
    * Simplified i915_vma_unbind which does not need to count the GGTT views.
      (Daniel Vetter)
    * Also moved obj->map_and_fenceable reset under the same check.
    * Checkpatch cleanups.

v3:
    * Only retire objects once the last VMA is unbound.

v4:
    * Keep scatter-gather table for alternative views persistent for the
      lifetime of the VMA.
    * Propagate binding errors to callers and handle appropriately.

v5:
    * Explicitly look for normal GGTT view in i915_gem_obj_bound to align
      usage in i915_gem_object_ggtt_unpin. (Michel Thierry)
    * Change to single if statement in i915_gem_obj_to_ggtt. (Michel Thierry)
    * Removed stray semi-colon in i915_gem_object_set_cache_level.

For: VIZ-4544
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Michel Thierry <michel.thierry@intel.com>
[danvet: Drop hunk from i915_gem_shrink since it's just prettification
but upsets a __must_check warning.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-12-15 11:25:04 +01:00
Daniel Vetter 8f0e2b9d95 drm/i915: Move golden context init into ->init_context
Similar to a patch from Thomas Daniel for lrc contexts. This keeps
both sides somewhat in sync and should make Dave Gordon happy.

Note that both the wa and the golden context init code suffer a bit
from an inssuficient split into driver load and hw init code. Which
means we have a bunch of tests all over the place to check whether the
one-time initialization has been done already or not.

All that one-tim code should be moved into the one-time ring setup
code, but that's work for later.

Cc: Dave Gordon <david.s.gordon@intel.com>
Cc: Thomas Daniel <thomas.daniel@intel.com>
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>
2014-12-08 15:19:02 +01:00
Thomas Daniel e7778be1ea drm/i915: Fix startup failure in LRC mode after recent init changes
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>
2014-12-03 09:35:30 +01:00
John Harrison 41c5241555 drm/i915: Remove the now redundant 'obj->ring'
The ring member of the object structure was always updated with the
last_read_seqno member. Thus with the conversion to last_read_req, obj->ring is
now a direct copy of obj->last_read_req->ring. This makes it somewhat redundant
and potentially misleading (especially as there was no comment to explain its
purpose).

This checkin removes the redundant field. Many uses were simply testing for
non-null to see if the object is active on the GPU. Some of these have been
converted to check 'obj->active' instead. Others (where the last_read_req is
about to be used anyway) have been changed to check obj->last_read_req. The rest
simply pull the ring out from the request structure and proceed as before.

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>
2014-12-03 09:35:23 +01:00
Michel Thierry 771b9a5324 drm/i915: Initialize workarounds in logical ring mode too
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>
2014-11-14 10:29:25 +01:00
Daniele Ceraolo Spurio 198c974d7e drm/i915: Add tracepoints to track a vm during its lifetime
- ppgtt init/release: these tracepoints are useful for observing the
  creation and destruction of Full PPGTTs.

- ctx create/free: we can use the ctx_free trace in combination with the
  ppgtt_release one to be sure that the ppgtt doesn't stay alive for too
  long after the ctx is destroyed. ctx_create is there for simmetry

- switch_mm: important point in the lifetime of the vm

v4: add DOC information
v5: pull the DOC in drm.tmpl
v6: clean ppgtt init/release traces + add ctx create/free and switch_mm
    tracepoints (Chris)
v7: drop execlist_submit_context tracepoint

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-11-14 10:29:13 +01:00
Tvrtko Ursulin aff437667b drm/i915: Move flags describing VMA mappings into the VMA
If these flags are on the object level it will be more difficult to allow
for multiple VMAs per object.

v2: Simplification and cleanup after code review comments (Chris Wilson).

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>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-11-04 14:04:51 +01:00
Arun Siluvery 86d7f23842 drm/i915/bdw: Apply workarounds in render ring init function
For BDW workarounds are currently initialized in init_clock_gating() but
they are lost during reset, suspend/resume etc; this patch moves the WAs
that are part of register state context to render ring init fn otherwise
default context ends up with incorrect values as they don't get initialized
until init_clock_gating fn.

v2: Add workarounds to golden render state
This method has its own issues, first of all this is different for
each gen and it is generated using a tool so adding new workaround
and mainitaining them across gens is not a straightforward process.

v3: Use LRIs to emit these workarounds (Ville)
Instead of modifying the golden render state the same LRIs are
emitted from within the driver.

v4: Use abstract name when exporting gen specific routines (Chris)

For: VIZ-4092
Signed-off-by: Arun Siluvery <arun.siluvery@linux.intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-09-03 11:04:42 +02:00
Thomas Daniel ecdb5fd861 drm/i915/bdw: Don't execute context reset and switch with Execlists
These two functions make no sense in an Logical Ring Context & Execlists
world.

v2: We got rid of lrc_enabled and centralized everything in the sanitized
i915.enable_execlists instead.

Signed-off-by: Oscar Mateo <oscar.mateo@intel.com>

v3: Rebased.  Corrected a typo in comment for i915_switch_context and
added a comment that it should not be called in execlist mode. Added
WARN_ON if i915_switch_context is called in execlist mode. Moved check
for execlist mode out of i915_switch_context and into callers. Added
comment in context_reset explaining why nothing is done in execlist
mode.

Signed-off-by: Thomas Daniel <thomas.daniel@intel.com>
[danvet: Simplify the patch subject so I can understand it.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-09-03 11:04:17 +02:00
Ben Widawsky e80f14b6d3 drm/i915: Don't save/restore RS when not used
v2: fix conflict on rebase.

Cc: Kenneth Graunke <kenneth@whitecape.org>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-09-03 11:03:53 +02:00
McAulay, Alistair 6689c167ae drm/i915: Rework GPU reset sequence to match driver load & thaw
This patch is to address Daniels concerns over different code during reset:

http://lists.freedesktop.org/archives/intel-gfx/2014-June/047758.html

"The reason for aiming as hard as possible to use the exact same code for
driver load, gpu reset and runtime pm/system resume is that we've simply
seen too many bugs due to slight variations and unintended omissions."

Tested using igt drv_hangman.

V2: Cleaner way of preventing check_wedge returning -EAGAIN
V3: Clean the last_context during reset, to ensure do_switch() does the MI_SET_CONTEXT. As per review.
Signed-off-by: McAulay, Alistair <alistair.mcaulay@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
[danvet: Rebase over ctx->ppgtt rework and extend the comment in
check_wedge a bit.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-09-03 10:54:09 +02:00
Daniel Vetter d624d86e1e drm/i915: Drop create_vm argument to i915_gem_create_context
Now that all the flow is streamlined the rule is simple: We create
a new ppgtt for a new context when we have full ppgtt enabled.

Reviewed-by: Michel Thierry <michel.thierry@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-08-13 14:23:33 +02:00
Daniel Vetter ae6c480692 drm/i915: Only track real ppgtt for a context
There's a bit a confusion since we track the global gtt,
the aliasing and real ppgtt in the ctx->vm pointer. And not
all callers really bother to check for the different cases and just
presume that it points to a real ppgtt.

Now looking closely we don't actually need ->vm to always point at an
address space - the only place that cares actually has fixup code
already to decide whether to look at the per-proces or the global
address space.

So switch to just tracking the ppgtt directly and ditch all the
extraneous code.

v2: Fixup the ppgtt debugfs file to not oops on a NULL ctx->ppgtt.
Also drop the early exit - without aliasing ppgtt we want to dump all
the ppgtts of the contexts if we have full ppgtt.

v3: Actually git add the compile fix.

Reviewed-by: Michel Thierry <michel.thierry@intel.com>
Cc: "Thierry, Michel" <michel.thierry@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
OTC-Jira: VIZ-3724
[danvet: Resolve conflicts with execlist patches while applying.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-08-13 14:23:33 +02:00
Daniel Vetter fa76da3499 drm/i915: Initialize the aliasing ppgtt as part of global gtt
Stuffing this into the context setup code doesn't make a lot of sense.
Also reusing the real ppgtt setup code makes even less sense since the
aliasing ppgtt isn't a real address space. Leaving all that stuff
unitialized will make sure that we catch any abusers promptly.

This is also a prep work to clean up the context->ppgtt link.

v2: Fix up the logic fail, I've fumbled it so badly to completely
disable ppgtt on gen6. Spotted by Ville and Michel. Also move around
the pde write into the gen6 init function, since otherwise it won't
work at all.

v3: Only initialize the aliasing ppgtt when we actually enable it.

Cc: "Thierry, Michel" <michel.thierry@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Michel Thierry <michel.thierry@intel.com>
[danvet: Squash in fixup from Fengguang Wu.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-08-13 14:23:32 +02:00
Daniel Vetter 82460d9724 drm/i915: Rework ppgtt init to no require an aliasing ppgtt
Currently we abuse the aliasing ppgtt to set up the ppgtt support in
general. Which is a bit backwards since with full ppgtt we don't ever
need the aliasing ppgtt.

So untangle this and separate the ppgtt init from the aliasing
ppgtt. While at it drag it out of the context enabling (which just
does a switch to the default context).

Note that we still have the differentiation between synchronous and
asynchronous ppgtt setup, but that will soon vanish. So also correctly
wire up the return value handling to be prepared for when ->switch_mm
drops the synchronous parameter and could start to fail.

Reviewed-by: Michel Thierry <michel.thierry@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-08-13 14:23:31 +02:00
Daniel Vetter 4d884705da drm/i915: Track file_priv, not ctx in the ppgtt structure
Hardware contexts reference a ppgtt, not the other way round. And the
only user of this (in debugfs) actually only cares about which file
the ppgtt is associated with. So give it what it wants.

While at it give the ppgtt create function a proper name&place.

Reviewed-by: Michel Thierry <michel.thierry@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-08-13 14:23:28 +02:00
Daniel Vetter ee960be7bb drm/i915: Some cleanups for the ppgtt lifetime handling
So when reviewing Michel's patch I've noticed a few things and cleaned
them up:
- The early checks in ppgtt_release are now redundant: The inactive
  list should always be empty now, so we can ditch these checks. Even
  for the aliasing ppgtt (though that's a different confusion) since
  we tear that down after all the objects are gone.
- The ppgtt handling functions are splattered all over. Consolidate
  them in i915_gem_gtt.c, give them OCD prefixes and add wrappers for
  get/put.
- There was a bit a confusion in ppgtt_release about whether it cares
  about the active or inactive list. It should care about them both,
  so augment the WARNINGs to check for both.

There's still create_vm_for_ctx left to do, put that is blocked on the
removal of ppgtt->ctx. Once that's done we can rename it to
i915_ppgtt_create and move it to its siblings for handling ppgtts.

v2: Move the ppgtt checks into the inline get/put functions as
suggested by Chris.

v3: Inline the now redundant ppgtt local variable.

Cc: Michel Thierry <michel.thierry@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Michel Thierry <michel.thierry@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-08-12 15:24:04 +02:00
Michel Thierry b9d06dd9d1 drm/i915: vma/ppgtt lifetime rules
VMAs should take a reference of the address space they use.

Now, when the fd is closed, it will release the ref that the context was
holding, but it will still be referenced by any vmas that are still
active.

ppgtt_release() should then only be called when the last thing referencing
it releases the ref, and it can just call the base cleanup and free the
ppgtt.

Note that with this we will extend the lifetime of ppgtts which
contain shared objects. But all the non-shared objects will get
removed as soon as they drop of the active list and for the shared
ones the shrinker can eventually reap them. Since we currently can't
evict ppgtt pagetables either I don't think that temporary leak is
important.

Signed-off-by: Michel Thierry <michel.thierry@intel.com>
[danvet: Add note about potential ppgtt leak with this approach.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-08-12 15:22:26 +02:00
Oscar Mateo 48d823878d drm/i915/bdw: Generic logical ring init and cleanup
Allocate and populate the default LRC for every ring, call
gen-specific init/cleanup, init/fini the command parser and
set the status page (now inside the LRC object). These are
things all engines/rings have in common.

Stopping the ring before cleanup and initializing the seqnos
is left as a TODO task (we need more infrastructure in place
before we can achieve this).

v2: Check the ringbuffer backing obj for ring_is_initialized,
instead of the context backing obj (similar, but not exactly
the same).

Signed-off-by: Oscar Mateo <oscar.mateo@intel.com>
Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-08-11 16:55:17 +02:00
Oscar Mateo ec3e9963a6 drm/i915/bdw: Deferred creation of user-created LRCs
The backing objects and ringbuffers for contexts created via open
fd are actually empty until the user starts sending execbuffers to
them. At that point, we allocate & populate them. We do this because,
at create time, we really don't know which engine is going to be used
with the context later on (and we don't want to waste memory on
objects that we might never use).

v2: As contexts created via ioctl can only be used with the render
ring, we have enough information to allocate & populate them right
away.

v3: Defer the creation always, even with ioctl-created contexts, as
requested by Daniel Vetter.

Signed-off-by: Oscar Mateo <oscar.mateo@intel.com>
Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-08-11 16:25:58 +02:00
Oscar Mateo 8c8579176a drm/i915/bdw: A bit more advanced LR context alloc/free
Now that we have the ability to allocate our own context backing objects
and we have multiplexed one of them per engine inside the context structs,
we can finally allocate and free them correctly.

Regarding the context size, reading the register to calculate the sizes
can work, I think, however the docs are very clear about the actual
context sizes on GEN8, so just hardcode that and use it.

v2: Rebased on top of the Full PPGTT series. It is important to notice
that at this point we have one global default context per engine, all
of them using the aliasing PPGTT (as opposed to the single global
default context we have with legacy HW contexts).

v3:
- Go back to one single global default context, this time with multiple
  backing objects inside.
- Use different context sizes for non-render engines, as suggested by
  Damien (still hardcoded, since the information about the context size
  registers in the BSpec is, well, *lacking*).
- Render ctx size is 20 (or 19) pages, but not 21 (caught by Damien).
- Move default context backing object creation to intel_init_ring (so
  that we don't waste memory in rings that might not get initialized).

v4:
- Reuse the HW legacy context init/fini.
- Create a separate free function.
- Rename the functions with an intel_ preffix.

v5: Several rebases to account for the changes in the previous patches.

Signed-off-by: Ben Widawsky <ben@bwidawsk.net> (v1)
Signed-off-by: Oscar Mateo <oscar.mateo@intel.com>
Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-08-11 16:08:18 +02:00
Oscar Mateo ede7d42bae drm/i915/bdw: Initialization for Logical Ring Contexts
For the moment this is just a placeholder, but it shows one of the
main differences between the good ol' HW contexts and the shiny
new Logical Ring Contexts: LR contexts allocate  and free their
own backing objects. Another difference is that the allocation is
deferred (as the create function name suggests), but that does not
happen in this patch yet, because for the moment we are only dealing
with the default context.

Early in the series we had our own gen8_gem_context_init/fini
functions, but the truth is they now look almost the same as the
legacy hw context init/fini functions. We can always split them
later if this ceases to be the case.

Also, we do not fall back to legacy ringbuffers when logical ring
context initialization fails (not very likely to happen and, even
if it does, hw contexts would probably fail as well).

v2: Daniel says "explain, do not showcase".

Signed-off-by: Oscar Mateo <oscar.mateo@intel.com>
Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
[danvet: s/BUG_ON/WARN_ON/.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-08-11 16:04:11 +02:00
Ben Widawsky 2f29579131 drm/i915: Reorder ctx unref on ppgtt cleanup
The comment [which was mine] is wrong. The context object can never be
bound in a PPGTT because it is only capable of living in the Global GTT.
So, remove the comment, and reorder the unref. What's nice about the
latter is it keeps the context object alive past the PPGTT. This makes
the destroy ordering symmetric with the creation ordering.

Create:
1. Create context
2. Create PPGTT

Destroy:
1. Destroy PPGTT
2. Destroy context

As far as I know, this does not fix a bug. The code previously kept the
context data structure, only the object was gone. As the code was,
nothing tried to use the object after this point.

NOTE: If in the future we have cases where the PPGTT can/should outlive
the context (which doesn't occur today, but the code permits it), this
ordering does not matter. Even if this occurs, as it stands now, we do
not expect that to be the normal case, and having this order makes
debugging a bit easier if we're tracking object lifetimes for the
context vs ppgtt

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
[danvet: Resolve conflict with Oscar's execlist prep patches.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-07-23 07:05:39 +02:00
Oscar Mateo 821d66dd7c drm/i915: Emphasize that ctx->id is merely a user handle
This is an Execlists preparatory patch, since they make context ID become an
overloaded term:

- In the software, it was used to distinguish which context userspace was
  trying to use.
- In the BSpec, the term is used to describe the 20-bits long field the
  hardware uses to it to discriminate the contexts that are submitted to
  the ELSP and inform the driver about their current status (via Context
  Switch Interrupts and Context Status Buffers).

Initially, I tried to make the different meanings converge, but it proved
impossible:

- The software ctx->id is per-filp, while the hardware one needs to be
  globally unique.
- Also, we multiplex several backing states objects per intel_context,
  and all of them need unique HW IDs.
- I tried adding a per-filp ID and then composing the HW context ID as:
  ctx->id + file_priv->id + ring->id, but the fact that the hardware only
  uses 20-bits means we have to artificially limit the number of filps or
  contexts the userspace can create.

The ctx->user_handle renaming bits are done with this Cocci patch (plus
manual frobbing of the struct declaration):

    @@
    struct intel_context c;
    @@
    - (c).id
    + c.user_handle

    @@
    struct intel_context *c;
    @@
    - (c)->id
    + c->user_handle

Also, while we are at it, s/DEFAULT_CONTEXT_ID/DEFAULT_CONTEXT_HANDLE and
change the type to unsigned 32 bits.

v2: s/handle/user_handle and change the type to uint32_t as suggested by
Chris Wilson.

Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org> (v1)
Signed-off-by: Oscar Mateo <oscar.mateo@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-07-08 12:30:41 +02:00
Oscar Mateo ea0c76f8c3 drm/i915: Emphasize that ctx->obj & ctx->is_initialized refer to the legacy rcs ctx
We have already advanced that Logical Ring Contexts have their own kind
of backing objects, but everything will be better explained in the Execlists
series. For now, suffice it to say that the current backing object is only
ever used with the render ring, so we're making this fact more explicit
(which is a good reason on its own).

As for the is_initialized flag, we only use to signify that the render state
has been initialized (a.k.a. golden context, a.k.a. null context). It doesn't
mean anything for the other engines, so make that distinction obvious.

Done with the following Coccinelle patch (plus manual frobbing of the struct):

    @@
    struct intel_context c;
    @@
    - (c).obj
    + c.legacy_hw_ctx.rcs_state

    @@
    struct intel_context *c;
    @@
    - (c)->obj
    + c->legacy_hw_ctx.rcs_state

    @@
    struct intel_context c;
    @@
    - (c).is_initialized
    + c.legacy_hw_ctx.initialized

    @@
    struct intel_context *c;
    @@
    - (c)->is_initialized
    + c->legacy_hw_ctx.initialized

This Execlists prep-work patch has been suggested by Chris Wilson and Daniel
Vetter separately.

Initially, it was two separate patches:
drm/i915: Rename ctx->obj to ctx->rcs_state
drm/i915: Make it obvious that ctx->id is merely a user handle

Signed-off-by: Oscar Mateo <oscar.mateo@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
[danvet: s/id/is_initialized/ to fix the subject and resolve a
conflict in i915_gem_context_reset. Also introduce a new lctx local
variable to avoid overtly long lines.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-07-08 12:30:35 +02:00
Oscar Mateo aa0c13daad drm/i915: Extract context backing object allocation
This is preparatory work for Execlists: we plan to use it later to
allocate our own context objects (since Logical Ring Contexts do
not have the same kind of backing objects).

No functional changes.

Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Oscar Mateo <oscar.mateo@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-07-08 12:30:31 +02:00
Ville Syrjälä 4bfad3ddc8 drm/i915: Unpin last_context at reset
We're forgetting to unpin the last_context from the ggtt at GPU reset
time. This leads to the vma pin_count leaking at every reset if the
last context wasn't the ring default context. Further use of the same
context will trigger the pin_count check in i915_gem_object_pin() and
userspace will be faced with EBUSY as a result.

This plaques kms_flip rather badly since it performs lots of resets,
and every fd has its own default context these days.

Fix the problem by properly unpinning the last context at reset.

This regression seems to back to

commit acce9ffa48
Author: Ben Widawsky <ben@bwidawsk.net>
Date:   Fri Dec 6 14:11:03 2013 -0800

   drm/i915: Better reset handling for contexts

Testcase: igt/gem_ctx_exec/reset-pin-leak
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-07-07 17:21:56 +02:00
Daniel Vetter f1615bbe9b Linux 3.16-rc4
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Merge tag 'v3.16-rc4' into drm-intel-next-queued

Due to Dave's vacation drm-next hasn't opened yet for 3.17 so I
couldn't move my drm-intel-next queue forward yet like I usually do.
Just pull in the latest upstream -rc to unblock patch merging - I
don't want to needlessly rebase my current patch pile really and void
all the testing we've done already.

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-07-07 10:17:56 +02:00
Chris Wilson 967ab6b177 drm/i915: Only mark the ctx as initialised after a SET_CONTEXT operation
Fallout from

commit 46470fc932
Author: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Date:   Wed May 21 19:01:06 2014 +0300

    drm/i915: Add null state batch to active list

undid the earlier fix of only marking the ctx as initialised after it is
saved by the hardware during a SET_CONTEXT operation:

commit ad1d219974
Author: Ben Widawsky <benjamin.widawsky@intel.com>
Date:   Sat Dec 28 13:31:49 2013 -0800

    drm/i915: set ctx->initialized only after RCS

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Damien Lespiau <damien.lespiau@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Cc: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
[Jani: add reference to the earlier fix in the commit messsage.]
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
2014-06-24 14:48:41 +03:00
Oscar Mateo 14d8ec544f drm/i915: Remove ctx->last_ring
The original comment that introduced it said:

commit 0009e46cd5
Author: Ben Widawsky <ben@bwidawsk.net>
Date:   Fri Dec 6 14:11:02 2013 -0800

    drm/i915: Track which ring a context ran on

    Previously we dropped the association of a context to a ring. It is
    however very important to know which ring a context ran on (we could
    have reused the other member, but I was nitpicky).

    This is very important when we switch address spaces, which unlike
    context objects, do change per ring.

    As an example, if we have:

            RCS   BCS
    ctx            A
    ctx      A
    ctx      B
    ctx            B

    Without tracking the last ring B ran on, we wouldn't know to switch the
    address space on BCS in the last row.

But this is not really true, because we are already checking to != from (with
"from" being = ring->last_context) and that should be enough to make sure we
switch to the right address space.

We would have a problem if we switched the context object for every ring (since
then we would fail to do it in some situations) but we only switch it for the
render ring, so we don't care.

Signed-off-by: Oscar Mateo <oscar.mateo@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-06-18 21:42:42 +02:00
Oscar Mateo f83d6518a1 drm/i915: Kill private_default_ctx off
It's barely alive now anyway, so give it the "coup de grâce".

Signed-off-by: Oscar Mateo <oscar.mateo@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-05-22 23:44:44 +02:00
Oscar Mateo 273497e5cd drm/i915: s/i915_hw_context/intel_context
Up until now, contexts had one (and only one) backing object that was
used by the hardware to save/restore render ring contexts (via the
MI_SET_CONTEXT command). Other rings did not have or need this, so
our i915_hw_context struct had a 1:1 relationship with a a real HW
context.

With Logical Ring Contexts and Execlists, this is not possible anymore:
all rings need a backing object, and it cannot be reused. To prepare
for that, rename our contexts to the more generic term intel_context.

No functional changes.

Signed-off-by: Oscar Mateo <oscar.mateo@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-05-22 23:41:17 +02:00
Oscar Mateo a4872ba6d0 drm/i915: s/intel_ring_buffer/intel_engine_cs
In the upcoming patches we plan to break the correlation between
engine command streamers (a.k.a. rings) and ringbuffers, so it
makes sense to refactor the code and make the change obvious.

No functional changes.

Signed-off-by: Oscar Mateo <oscar.mateo@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-05-22 23:01:05 +02:00
Mika Kuoppala 46470fc932 drm/i915: Add null state batch to active list
for proper refcounting to take place as we use
i915_add_request() for it.

i915_add_request() also takes the context for the request
from ring->last_context so move the null state batch
submission after the ring context has been set.

v2: we need to check for correct ring now (Ville Syrjälä)
v3: no need to expose i915_gem_move_object_to_active (Chris Wilson)
v4: cargoculted vma/active/inactive error handling removed (Chris Wilson)

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-05-22 14:10:37 +02:00
Ville Syrjälä b3f797ac49 drm/i915/chv: Add some workaround notes
We implement the following workarounds:
* WaDisableAsyncFlipPerfMode:chv
* WaProgramMiArbOnOffAroundMiSetContext:chv

v2: Drop WaDisableSemaphoreAndSyncFlipWait note

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-05-20 15:20:05 +02:00
Chris Wilson d3b448d991 drm/i915: Only unpin the default ctx object if it exists
Since commit 691e6415c8
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date:   Wed Apr 9 09:07:36 2014 +0100

    drm/i915: Always use kref tracking for all contexts.

we have contexts everywhere, and so we must be careful to distinguish
fake contexts, which do not have an associated bo, and real ones, which
do. In particular, we now need to be careful not to dereference NULL
pointers.

This is one such example, as the commit highlighted above failed to move
the unpinning of the default ctx object into the real-context-only
branch.

Reported-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=78792
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Ben Widawsky <benjamin.widawsky@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-05-16 21:41:12 +02:00
Mika Kuoppala 9d0a6fa6c5 drm/i915: add render state initialization
HW guys say that it is not a cool idea to let device
go into rc6 without proper 3d pipeline state.

For each new uninitialized context, generate a
valid null render state to be run on context
creation.

This patch introduces a skeleton with empty states.

v2: - No need to vmap (Chris Wilson)
    - use .c files for state (Daniel Vetter)
    - no need to flush as i915_add_request does it
    - remove parameter for batch alloc size
    - don't wait for the init (Ben Widawsky)

v3: - move to cpu/gpu (Chris Wilson)

Tested-by: Kristen Carlson Accardi <kristen@linux.intel.com> (v1)
Tested-by: Oscar Mateo <oscar.mateo@intel.com>
Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-05-14 19:16:13 +02:00
Dave Airlie 885ac04ab3 Merge tag 'drm-intel-next-2014-04-16' of git://anongit.freedesktop.org/drm-intel into drm-next
drm-intel-next-2014-04-16:
- vlv infoframe fixes from Jesse
- dsi/mipi fixes from Shobhit
- gen8 pageflip fixes for LRI/SRM from Damien
- cmd parser fixes from Brad Volkin
- some prep patches for CHV, DRRS, ...
- and tons of little things all over
drm-intel-next-2014-04-04:
- cmd parser for gen7 but only in enforcing and not yet granting mode - the
  batch copying stuff is still missing. Also performance is a bit ... rough
  (Brad Volkin + OACONTROL fix from Ken).
- deprecate UMS harder (i.e. CONFIG_BROKEN)
- interrupt rework from Paulo Zanoni
- runtime PM support for bdw and snb, again from Paulo
- a pile of refactorings from various people all over the place to prep for new
  stuff (irq reworks, power domain polish, ...)

drm-intel-next-2014-04-04:
- cmd parser for gen7 but only in enforcing and not yet granting mode - the
  batch copying stuff is still missing. Also performance is a bit ... rough
  (Brad Volkin + OACONTROL fix from Ken).
- deprecate UMS harder (i.e. CONFIG_BROKEN)
- interrupt rework from Paulo Zanoni
- runtime PM support for bdw and snb, again from Paulo
- a pile of refactorings from various people all over the place to prep for new
  stuff (irq reworks, power domain polish, ...)

Conflicts:
	drivers/gpu/drm/i915/i915_gem_context.c
2014-05-01 09:11:37 +10:00
Chris Wilson 691e6415c8 drm/i915: Always use kref tracking for all contexts.
If we always initialize kref for the context, even if we are using fake
contexts for hangstats when there is no hw support, we can forgo the
dance to dereference the ctx->obj and inspect whether we are permitted
to use kref inside i915_gem_context_reference() and _unreference().

My ulterior motive here is to improve the debugging of a use-after-free
of ctx->obj. This patch avoids the dereference here and instead forces
the assertion checks associated with kref.

v2: Refactor the fake contexts to being even more like the real
contexts, so that there is much less duplicated and special case code.

v3: Tweaks.
v4: Tweaks, minor.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=76671
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Tested-by: lu hua <huax.lu@intel.com>
Cc: Ben Widawsky <benjamin.widawsky@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
[Jani: tiny change to backport to drm-intel-fixes.]
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
2014-04-11 13:29:51 +03:00
Ville Syrjälä ad2ac08bf3 drm/i915: Make contexts non-snooped on non-LLC platforms
We don't do CPU access to GPU contexts so making the GPU access snoop
the CPU caches seems silly, and potentially expensive.

v2: Use !IS_VALLEYVIEW instead of HAS_LLC as this is really
    about what the PTEs can represent.
    Add a comment clarifying the situation.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-04-09 14:37:10 +02:00
Ben Widawsky 057f6a8ad7 drm/i915: Invariably invalidate before ctx switch
We have been setting the bit which was originally BIOS dependent since:
commit f05bb0c7b6
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date:   Sun Jan 20 16:33:32 2013 +0000

    drm/i915: GFX_MODE Flush TLB Invalidate Mode must be '1' for scanline waits

Therefore, we do not need to try to figure it out dynamically and we can
just always invalidate the TLBs.

It's a partial revert of:
commit 12b0286f49
Author: Ben Widawsky <ben@bwidawsk.net>
Date:   Mon Jun 4 14:42:50 2012 -0700

    drm/i915: possibly invalidate TLB before context switch

The original commit attempted to only invalidate when necessary
(very much a relic from the old days). Now, we can just always invalidate.

I guess the old TODO still exists. Since we seem to have abandoned ILK
contexts however, there isn't much point in even remembering.

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-04-03 11:41:39 +02:00
Ville Syrjälä 64bed78820 drm/i915: Implement WaProgramMiArbOnOffAroundMiSetContext:bdw
BSpec seems to tell us we need the MI_ARB_ON_OFF w/a around
MI_SET_CONTEXT on gen8.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-04-02 09:11:22 +02:00
Chris Wilson 6313c20490 drm/i915: Per-process stats work better when evaluated per-process
The idea of printing objects used by each process is to judge how each
process is using them. This means that we need to evaluate whether the
object is bound for that particular process, rather than just whether it
is bound into the global GTT.

v2: Restore the non-full-ppgtt path for simplicity as we may not even
    create vma with older hardware.

v3: Tweak handling of global entries and default context entries.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Ben Widawsky <benjamin.widawsky@intel.com>
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-03-20 15:09:21 +01:00
Mika Kuoppala a95f6a0070 drm/i915: Switch to fake context on older gens
We used to have per file descriptor hang stats for the
i915_get_reset_stats_ioctl() and for default context banning.

commit 0eea67eb26
Author: Ben Widawsky <ben@bwidawsk.net>
Date:   Fri Dec 6 14:11:19 2013 -0800

    drm/i915: Create a per file_priv default context

made having separate hangstats in file_private redundant
as i915_hw_context already contained hangstats. So

commit c482972a08
Author: Ben Widawsky <benjamin.widawsky@intel.com>
Date:   Fri Dec 6 14:11:20 2013 -0800

    drm/i915: Piggy back hangstats off of contexts

consolidated the hangstats and enabled further improvements.

commit 44e2c0705a
Author: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Date:   Thu Jan 30 16:01:15 2014 +0200

    drm/i915: Use i915_hw_context to set reset stats

tried to reap full benefits of consolidation but fell short
as we never 'switch' to the fake private context on gens
that don't have hw_contexts, so request->ctx remained NULL
on those.

Fix this by 'switching' to fake context so that when
request is submitted to ring, proper context gets assigned
to it.

Testcase: igt/drv_hangman
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=76055
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-03-18 16:31:35 +01:00
Damien Lespiau 96a6f0f1db drm/i915: Fix i915_switch_context() argument name in kerneldoc
While reading some code, out of boredom, stumbled on a tiny tiny fix.

Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-03-05 21:30:41 +01:00
Ben Widawsky b18b6bde30 drm/i915/bdw: Free PPGTT struct
GEN8 never freed the PPGTT struct. As GEN8 doesn't use full PPGTT, the
leak is small and only found on a module reload. ie. I don't think this
needs to go to stable.

v2: The very naive, kfree in gen8 ppgtt cleanup, is subject to a double
free on PPGTT initialization failure. (Spotted by Imre). Instead this
patch pulls the ppgtt struct freeing out of the cleanup and leaves it to
the allocators/callers or the one doing the last kref_put as in standard
convention

Reported-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-03-04 15:53:58 +01:00
Ben Widawsky 321f2ada91 drm/i915: Move ppgtt_release out of the header
At one time it was expected to be called in multiple places by kref_put.
At the current time however, it is all contained within
i915_gem_context.c.

This patch makes an upcoming required addition a bit nicer since it too
doesn't need to be defined in a header file.

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-03-04 15:52:15 +01:00
Thierry Reding d4d5be6192 drm/i915: Remove dead code
The i915 driver sets DRIVER_GEM unconditionally, so testing for the
feature will always fail.

Signed-off-by: Thierry Reding <treding@nvidia.com>
[danvet: Fix up conflicts.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-03-04 09:56:48 +01:00
Daniel Vetter 1ec9e26dda drm/i915: Consolidate binding parameters into flags
Anything more than just one bool parameter is just a pain to read,
symbolic constants are much better.

Split out from Chris' vma-binding rework patch.

v2: Undo the behaviour change in object_pin that Chris spotted.

v3: Split out misplaced hunk to handle set_cache_level errors,
spotted by Jani.

v4: Keep the current over-zealous binding logic in the execbuffer code
working with a quick hack while the overall binding code gets shuffled
around.

v5: Reorder the PIN_ flags for more natural patch splitup.

v6: Pull out the PIN_GLOBAL split-up again.

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Ben Widawsky <benjamin.widawsky@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-02-14 14:16:58 +01:00
Mika Kuoppala 7f76b23aae drm/i915: check for oom when allocating private_default_ctx
Found with smatch

Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-02-04 12:10:26 +01:00
Mika Kuoppala 3fac8978f5 drm/i915: Tune down debug output when context is banned
If we have stopped rings then we know that test is running
so no need for spam. In addition, only spam when default
context gets banned.

v2: - make sure default context ban gets shown (Chris)
    - use helper for checking for default context, everywhere (Chris)

v3: - dont be quiet when debug is set (Ben, Daniel)

Reference: https://bugs.freedesktop.org/show_bug.cgi?id=73652
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-01-30 17:25:38 +01:00
Ben Widawsky c5dc5cecf8 drm/i915: Create a USES_PPGTT macro
There are cases where we want to know if there is a full, or aliased
PPGTT. Currently, in fact the only distinction we ever need to make is
when we're using full PPGTT.

This patch is simply to promote readability and clarify for the
confusing existing usage where "aliasing" meant aliasing and full.

v2: Remove USES_ALIASING_PPGTT since there are currently no cases where
we need to check if we're using aliasing, but not full PPGTT. (Daniel)

Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-01-28 09:13:50 +01:00
Ville Syrjälä 2b7e8082b2 drm/i915: We implement WaMiSetContext_Hang
WaMiSetContext_Hang tells us that a MI_NOOP must follow MI_SET_CONTEXT.

The other thing WaMiSetContext_Hang seems to say is that URB_FENCE isn't
allowed to straddle two cachelines. But we don't issue those from the
kernel so we don't care.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-01-27 17:16:45 +01:00
Chris Wilson 42c3b603da drm/i915: Always pin the default context
Through a twisty and circuituous path it is possible to currently trick
the code into creating a default context and forgetting to pin it
immediately into the GGTT. (This requires a system using contexts without
an aliasing ppgtt, which is currently restricted to Baytrails machines
manually specifying a module parameter to force enable contexts, or
on Sandybridge and later that manually disable the aliasing ppgtt.) The
consequence is that during module unload we attempt to unpin the default
context twice and encounter a BUG remonstrating that we attempt to unpin
an unbound object.

[  161.002869] Kernel BUG at f84861f8 [verbose debug info unavailable]
[  161.002875] invalid opcode: 0000 [#1] SMP
[  161.002882] Modules linked in: coretemp kvm_intel kvm crc32_pclmul aesni_intel aes_i586 xts lrw gf128mul ablk_helper cryptd hid_sensor_accel_3d hid_sensor_gyro_3d hid_sensor_magn_3d hid_sensor_trigger industrialio_triggered_buffer kfifo_buf industrialio hid_sensor_iio_common snd_hda_codec_hdmi snd_hda_codec_realtek snd_hda_intel snd_hda_codec snd_hwdep snd_pcm snd_page_alloc snd_seq_midi snd_seq_midi_event dm_multipath scsi_dh asix ppdev usbnet snd_rawmidi mii hid_sensor_hub microcode snd_seq rfcomm bnep snd_seq_device bluetooth snd_timer snd parport_pc binfmt_misc soundcore dw_dmac_pci dw_dmac_core mac_hid lp parport dm_mirror dm_region_hash dm_log hid_generic usbhid hid i915(O-) drm_kms_helper(O) igb dca ptp pps_core i2c_algo_bit drm(O) ahci libahci video
[  161.002991] CPU: 0 PID: 2114 Comm: rmmod Tainted: G        W  O 3.13.0-rc8+ #2
[  161.002997] Hardware name: NEXCOM VTC1010/Aptio CRB, BIOS 5.6.5 09/24/2013
[  161.003004] task: dbdd6800 ti: dbe0e000 task.ti: dbe0e000
[  161.003010] EIP: 0060:[<f84861f8>] EFLAGS: 00010246 CPU: 0
[  161.003044] EIP is at i915_gem_object_ggtt_unpin+0x88/0x90 [i915]
[  161.003050] EAX: dfce3840 EBX: 00000000 ECX: dfafd690 EDX: dfce3874
[  161.003056] ESI: c0086b40 EDI: df962e00 EBP: dbe0fe1c ESP: dbe0fe0c
[  161.003062]  DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068
[  161.003068] CR0: 8005003b CR2: b7718000 CR3: 1bec0000 CR4: 001007f0
[  161.003076] Stack:
[  161.003081]  00afc014 00000004 c0086b40 dfafc000 dbe0fe38 f8487e5a dfaa5400 c0086b40
[  161.003099]  dfafc000 dfaa5400 dfaa5414 dbe0fe58 f84741aa 00000000 f89c34b9 dfaa5414
[  161.003117]  dfaa5400 dfaa5400 f644b000 dbe0fe6c f89a5443 dfaa5400 f8505000 f644b000
[  161.003134] Call Trace:
[  161.003169]  [<f8487e5a>] i915_gem_context_fini+0xba/0x1c0 [i915]
[  161.003202]  [<f84741aa>] i915_driver_unload+0x1fa/0x2f0 [i915]
[  161.003232]  [<f89a5443>] drm_dev_unregister+0x23/0x90 [drm]
[  161.003259]  [<f89a54ed>] drm_put_dev+0x3d/0x70 [drm]
[  161.003294]  [<f8470615>] i915_pci_remove+0x15/0x20 [i915]
[  161.003306]  [<c1338a6f>] pci_device_remove+0x2f/0xa0
[  161.003317]  [<c140c871>] __device_release_driver+0x61/0xc0
[  161.003328]  [<c140d12f>] driver_detach+0x8f/0xa0
[  161.003341]  [<c140c54f>] bus_remove_driver+0x4f/0xc0
[  161.003353]  [<c140d708>] driver_unregister+0x28/0x60
[  161.003362]  [<c10cee42>] ? stop_cpus+0x32/0x40
[  161.003372]  [<c10bd510>] ? module_refcount+0x90/0x90
[  161.003383]  [<c13378c5>] pci_unregister_driver+0x15/0x60
[  161.003413]  [<f89a739f>] drm_pci_exit+0x9f/0xb0 [drm]
[  161.003458]  [<f84e624a>] i915_exit+0x1b/0x1d [i915]
[  161.003468]  [<c10bf8a8>] SyS_delete_module+0x158/0x1f0
[  161.003480]  [<c1173d5d>] ? ____fput+0xd/0x10
[  161.003488]  [<c106f0fe>] ? task_work_run+0x7e/0xb0
[  161.003499]  [<c165a68d>] sysenter_do_call+0x12/0x28
[  161.003505] Code: 0f b6 4d f3 8d 51 0f 83 e1 f0 83 e2 0f 09 d1 84 d2 88 48 54 75 07 80 a7 91 00 00 00 7f 83 c4 04 5b 5e 5f 5d c3 8d b6 00 00 00 00 <0f> 0b 8d b6 00 00 00 00 55 89 e5 57 56 53 83 ec 64 3e 8d 74 26
[  161.003586] EIP: [<f84861f8>] i915_gem_object_ggtt_unpin+0x88/0x90 [i915] SS:ESP 0068:dbe0fe0c

v2: Rename the local variable (is_default_ctx) to avoid confusion with
the function is_default_ctx(). And correct Jesse's email address.

Reported-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=73985
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Ben Widawsky <benjamin.widawsky@intel.com>
Tested-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: Ben Widawsky <benjamin.widawsky@intel.com>
[danvet: Fix up the rebase fail from my first attempt, thankfully
pointed out by Ville.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-01-27 17:16:10 +01:00
Ben Widawsky ad1d219974 drm/i915: set ctx->initialized only after RCS
The initialized flag is used to specify a context has been initialized
and it's context is safe to load, ie. the 3d state is setup properly.
With full PPGTT, we emit the address space loads during context switch
and this currently marks a context as initialized. With full PPGTT
patches, if a client first emits a batch to !RCS, then later, RCS, the
code will mistake the context as initialized and try to reload an
uninitialized context.

1. context 1 blit // context marked as initialized, but isn't
2. context 1 render // loads random state from step 2

It is really easy to hit this with a planned upcoming patch which makes
default context reuse possible.

NOTE: This should only effect full PPGTT branches, ie. current
drm-intel-nightly.

Thanks to Chris for helping me track this down.

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
[danvet: Simplify the failure scenario in the commit message according
to Chris' review a bit.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-01-10 08:21:51 +01:00
Ben Widawsky c2cf2416ca drm/i915/bdw: Return -ENONENT on default ctx destroy
This was an accidental "ABI" change introduced during PPGTT:

commit 0eea67eb26
Author: Ben Widawsky <ben@bwidawsk.net>
Date:   Fri Dec 6 14:11:19 2013 -0800

    drm/i915: Create a per file_priv default context

The failure test application actually tests the return type. The other
option is to simply change the test.

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-01-10 08:21:50 +01:00
Ben Widawsky 72ad5c45f0 drm/i915/ppgtt: Fix ioctl errno for "no such context"
Without this fix the ioctls silently succeeded (but actually did
nothing).

It makes all the code which calls into this function way too confusing.

v2: Fix destroy IOCTL as well

v3: Clarify the other two callers of i915_gem_context_get() to never
check for NULL. (Mika)

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=72903
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Testcase: igt/gem_ctx_exec/basic
[danvet: Fix up the commit message and actually bother to mention the
testcase this fixes.]
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-01-07 08:50:11 +01:00
Ben Widawsky 7e0d96bc03 drm/i915: Use multiple VMs -- the point of no return
As with processes which run on the CPU, the goal of multiple VMs is to
provide process isolation. Specific to GEN, there is also the ability to
map more objects per process (2GB each instead of 2Gb-2k total).

For the most part, all the pipes have been laid, and all we need to do
is remove asserts and actually start changing address spaces with the
context switch. Since prior to this we've converted the setting of the
page tables to a streamed version, this is quite easy.

One important thing to point out (since it'd been hotly contested) is
that with this patch, every context created will have it's own address
space (provided the HW can do it).

v2: Disable BDW on rebase

NOTE: I tried to make this commit as small as possible. I needed one
place where I could "turn everything on" and that is here. It could be
split into finer commits, but I didn't really see much point.

Cc: Eric Anholt <eric@anholt.net>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-12-18 16:24:52 +01:00
Daniel Vetter 3d7f0f9dcc Merge commit drm-intel-fixes into topic/ppgtt
I need the tricky do_switch fix before I can merge the final piece of
the ppgtt enabling puzzle. Otherwise the conflict will be a real pain
to resolve since the do_switch hunk from -fixes must be placed at the
exact right place within a hunk in the next patch.

Conflicts:
	drivers/gpu/drm/i915/i915_gem_context.c
	drivers/gpu/drm/i915/i915_gem_execbuffer.c
	drivers/gpu/drm/i915/intel_display.c

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-12-18 16:23:37 +01:00
Ben Widawsky 41bde5535a drm/i915: Get context early in execbuf
We need to have the address space when reserving space for the objects.
Since the address space and context are tied together, and reserve
occurs before context switch (for good reason), we must lookup our
context earlier in the process.

This leaves some room for optimizations where we no longer need to use
ctx_id in certain places. This will be addressed in a subsequent patch.

Important tricky bit:
Because slow relocations during execbuffer drop struct_mutex

Perhaps it would be best to acquire the reference when we get the
context, but I'll save that for another day (note I have written the
patch before, and I found the changes required to be uglier than this).

Note that since we currently access everything via context id, and not
the data structure this is fine, though not desirable. The next change
attempts to get the context only once via the context ID idr lookup, and
as such, the following can happen:

CTX-A is created, refcount = 1
CTX-A execbuf, mutex dropped
close IOCTL called on CTX-A, refcount = 0
CTX-A resumes in execbuf.

v2: Rebased on top of
commit b6359918b8
Author: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Date:   Wed Oct 30 15:44:16 2013 +0200

    drm/i915: add i915_get_reset_stats_ioctl

v3: Rebased on top of
commit 25b3dfc87b
Author: Mika Westerberg <mika.westerberg@linux.intel.com>
Date:   Tue Nov 12 11:57:30 2013 +0200

Author: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Date:   Tue Nov 26 16:14:33 2013 +0200

    drm/i915: check context reset stats before relocations

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-12-18 15:52:42 +01:00
Ben Widawsky c482972a08 drm/i915: Piggy back hangstats off of contexts
To simplify the codepaths somewhat, we can simply always create a
context. Contexts already keep hangstat information. This prevents us
from having to differentiate at other parts in the code.

There is allocation overhead, but it should not be measurable.

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-12-18 15:51:58 +01:00
Ben Widawsky 0eea67eb26 drm/i915: Create a per file_priv default context
Every file will get it's own context, and we use this context instead of
the default context. The default context still exists for future
shrinker usage as well as reset handling.

v2: Updated to address Mika's recent context guilty changes
Some more changes around this come up in later patches as well.

v3: Use a fake context to avoid allocation for the !HAS_HW_CONTEXT case.
I've tried the alternatives. This looks the best to me.
Removed hangstat stuff from v2 - for a separate patch
Demote failed PPGTT set to DRM_DEBUG_DRIVER since it can now be invoked
easily from userspace.

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-12-18 15:44:29 +01:00
Ben Widawsky bdf4fd7ea0 drm/i915: Do aliasing PPGTT init with contexts
We have a default context which suits the aliasing PPGTT well. Tie them
together so it looks like any other context/PPGTT pair. This makes the
code cleaner as it won't have to special case aliasing as often.

The patch has one slightly tricky part in the default context creation
function. In the future (and on aliased setup) we create a new VM for a
context (potentially). However, if we have aliasing PPGTT, which occurs
at this point in time for all platforms GEN6+, we can simply manage the
refcounting to allow things to behave as normal. Now is a good time to
recall that the aliasing_ppgtt doesn't have a real VM, it uses the GGTT
drm_mm.

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-12-18 15:32:14 +01:00
Ben Widawsky c7c48dfdff drm/i915: Add VM to context
Pretty straightforward so far except for the bit about the refcounting.
The PPGTT will potentially be shared amongst multiple contexts. Because
contexts themselves have a refcounted lifecycle, the easiest way to
manage this will be to refcount the PPGTT. To acheive this, we piggy
back off of the existing context refcount, and will increment and
decrement the PPGTT refcount with context creation, and destruction.

To put it more clearly, if context A, and context B both use PPGTT 0, we
can't free the PPGTT until both A, and B are destroyed.

Note that because the PPGTT is permanently pinned (for now), it really
just matters for the PPGTT destruction, as opposed to making space under
memory pressure.

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-12-18 15:31:20 +01:00
Ben Widawsky a45d0f6a7f drm/i915: Generalize default context setup
The plan to to make every file descriptor have a default context. To
accommodate this, generalize out default context setup function so it
can be used at file open time.

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-12-18 15:27:56 +01:00
Ben Widawsky 2fa48d8d4a drm/i915: Split context enabling from init
We **need** to do this for exactly 1 reason, because we want to embed a
PPGTT into the context, but we don't want to special case the default
context.

To achieve that, we must be able to initialize contexts after the GTT is
setup (so we can allocate and pin the default context's BO), but before
the PPGTT and rings are initialized. This is because, currently, context
initialization requires ring usage. We don't have rings until after the
GTT is setup. If we split the enabling part of context initialization,
the part requiring the ringbuffer, we can untangle this, and then later
embed the PPGTT

Incidentally this allows us to also adhere to the original design of
context init/fini in future patches: they were only ever meant to be
called at driver load and unload.

v2: Move hw_contexts_disabled test in i915_gem_context_enable() (Chris)

v3: BUG_ON after checking for disabled contexts. Or else it blows up pre
gen6 (Ben)

v4: Forward port
Modified enable for each ring, since that patch is earlier in the series
Dropped ring arg from create_default_context so it can be used by others

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-12-18 15:27:55 +01:00
Ben Widawsky acce9ffa48 drm/i915: Better reset handling for contexts
This patch adds to changes for contexts on reset:
Sets last context to default - this will prevent the context switch
happening after a reset. That switch is not possible because the
rings are hung during reset and context switch requires reset. This
behavior will need to be reworked in the future, but this is what we
want for now.

In the future, we'll also want to reset the guilty context to
uninitialized. We should wait for ARB_Robustness related code to land
for that.

This is somewhat for paranoia.  Because we really don't know what the
GPU was doing when it hung, or the state it was in (mid context write,
for example), later restoring the context is a bad idea. By setting the
flag to not initialized, the next load of that context will not restore
the state, and thus on the subsequent switch away from the context will
overwrite the old data.

NOTE: This code needs a fixup when we actually have multiple VMs. The
issue that can occur is inactive objects in a VM will need to be
destroyed before the last context unref. This can now happen via the
fake switch introduced in this patch (and it other ways in the future)

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-12-18 15:27:54 +01:00
Ben Widawsky 0009e46cd5 drm/i915: Track which ring a context ran on
Previously we dropped the association of a context to a ring. It is
however very important to know which ring a context ran on (we could
have reused the other member, but I was nitpicky).

This is very important when we switch address spaces, which unlike
context objects, do change per ring.

As an example, if we have:

        RCS   BCS
ctx            A
ctx      A
ctx      B
ctx            B

Without tracking the last ring B ran on, we wouldn't know to switch the
address space on BCS in the last row.

As a result, we no longer need to track which ring a context "belongs"
to, as it never really made much sense anyway.

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-12-18 15:27:54 +01:00
Ben Widawsky 67e3d2979b drm/i915: Permit contexts on all rings
If we want to use contexts in more abstract terms (specifically with
PPGTT in mind), we need to allow them to be specified for any ring.

Since the upcoming patches will bring about the use of multiple address
spaces, and each ring needs to have an address space programmed (which
we intend to do at context switch time), we can no longer only use RCS.

With multiple rings having a last context, we must now unreference these
contexts.

NOTE: This commit requires an update to intel-gpu-tools to make it not
fail.

v2: Rebased with some logical conflicts.
Squashed in the context fini refcount patch

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-12-18 15:27:53 +01:00
Ben Widawsky b731d33d05 drm/i915: relax context alignment
With the introduction of contexts per fd in the future, one can easily
envision more contexts being used. We do not have an easy remedy to
reduce the space requirements of the contexts, we can make things
slightly better by using less stringent alignments on later hardware.

Ville: Since I can almost predict you'll point this out. I can no longer
find the docs which specify the 64k requirement on certain gen6 SKUs. If
you'd like to change that too, be my guest.

CC: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-12-18 15:27:52 +01:00
Ben Widawsky e422b888eb drm/i915: Add a context open function
We'll be doing a bit more stuff with each file, so having our own open
function should make things clean.

This also allows us to easily add conditionals for stuff we don't want
to do when we don't have HW contexts.

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-12-18 15:27:51 +01:00
Ben Widawsky 6f65e29aca drm/i915: Create bind/unbind abstraction for VMAs
To sum up what goes on here, we abstract the vma binding, similarly to
the previous object binding. This helps for distinguishing legacy
binding, versus modern binding. To keep the code churn as minimal as
possible, I am leaving in insert_entries(). It serves as the per
platform pte writing basically. bind_vma and insert_entries do share a
lot of similarities, and I did have designs to combine the two, but as
mentioned already... too much churn in an already massive patchset.

What follows are the 3 commits which existed discretely in the original
submissions. Upon rebasing on Broadwell support, it became clear that
separation was not good, and only made for more error prone code. Below
are the 3 commit messages with all their history.

drm/i915: Add bind/unbind object functions to VMA
drm/i915: Use the new vm [un]bind functions
drm/i915: reduce vm->insert_entries() usage

drm/i915: Add bind/unbind object functions to VMA

As we plumb the code with more VM information, it has become more
obvious that the easiest way to deal with bind and unbind is to simply
put the function pointers in the vm, and let those choose the correct
way to handle the page table updates. This change allows many places in
the code to simply be vm->bind, and not have to worry about
distinguishing PPGTT vs GGTT.

Notice that this patch has no impact on functionality. I've decided to
save the actual change until the next patch because I think it's easier
to review that way. I'm happy to squash the two, or let Daniel do it on
merge.

v2:
Make ggtt handle the quirky aliasing ppgtt
Add flags to bind object to support above
Don't ever call bind/unbind directly for PPGTT until we have real, full
PPGTT (use NULLs to assert this)
Make sure we rebind the ggtt if there already is a ggtt binding.  This
happens on set cache levels.
Use VMA for bind/unbind (Daniel, Ben)

v3: Reorganize ggtt_vma_bind to be more concise and easier to read
(Ville). Change logic in unbind to only unbind ggtt when there is a
global mapping, and to remove a redundant check if the aliasing ppgtt
exists.

v4: Make the bind function a bit smarter about the cache levels to avoid
unnecessary multiple remaps. "I accept it is a wart, I think unifying
the pin_vma / bind_vma could be unified later" (Chris)
Removed the git notes, and put version info here. (Daniel)

v5: Update the comment to not suck (Chris)

v6:
Move bind/unbind to the VMA. It makes more sense in the VMA structure
(always has, but I was previously lazy). With this change, it will allow
us to keep a distinct insert_entries.

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>

drm/i915: Use the new vm [un]bind functions

Building on the last patch which created the new function pointers in
the VM for bind/unbind, here we actually put those new function pointers
to use.

Split out as a separate patch to aid in review. I'm fine with squashing
into the previous patch if people request it.

v2: Updated to address the smart ggtt which can do aliasing as needed
Make sure we bind to global gtt when mappable and fenceable. I thought
we could get away without this initialy, but we cannot.

v3: Make the global GTT binding explicitly use the ggtt VM for
bind_vma(). While at it, use the new ggtt_vma helper (Chris)

At this point the original mailing list thread diverges. ie.

v4^:
use target_obj instead of obj for gen6 relocate_entry
vma->bind_vma() can be called safely during pin. So simply do that
instead of the complicated conditionals.
Don't restore PPGTT bound objects on resume path
Bug fix in resume path for globally bound Bos
Properly handle secure dispatch
Rebased on vma bind/unbind conversion

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>

drm/i915: reduce vm->insert_entries() usage

FKA: drm/i915: eliminate vm->insert_entries()

With bind/unbind function pointers in place, we no longer need
insert_entries. We could, and want, to remove clear_range, however it's
not totally easy at this point. Since it's used in a couple of place
still that don't only deal in objects: setup, ppgtt init, and restore
gtt mappings.

v2: Don't actually remove insert_entries, just limit its usage. It will
be useful when we introduce gen8. It will always be called from the vma
bind/unbind.

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> (v1)
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-12-18 15:27:50 +01:00
Ben Widawsky d7f46fc4e7 drm/i915: Make pin count per VMA
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-12-18 15:27:49 +01:00
Daniel Vetter acc240d41e drm/i915: Fix use-after-free in do_switch
So apparently under ridiculous amounts of memory pressure we can get
into trouble in do_switch when we try to move the old hw context
backing storage object onto the active lists.

With list debugging enabled that usually results in us chasing a
poisoned pointer - which means we've hit upon a vma that has been
removed from all lrus with list_del (and then deallocated, so it's a
real use-after free).

Ian Lister has done some great callchain chasing and noticed that we
can reenter do_switch:

i915_gem_do_execbuffer()

i915_switch_context()

do_switch()
   from = ring->last_context;
   i915_gem_object_pin()

      i915_gem_object_bind_to_gtt()
         ret = drm_mm_insert_node_in_range_generic();
         // If the above call fails then it will try i915_gem_evict_something()
         // If that fails it will call i915_gem_evict_everything() ...
	 i915_gem_evict_everything()
	    i915_gpu_idle()
	       i915_switch_context(DEFAULT_CONTEXT)

Like with everything else where the shrinker or eviction code can
invalidate pointers we need to reload relevant state.

Note that there's no need to recheck whether a context switch is still
required because:

- Doing a switch to the same context is harmless (besides wasting a
  bit of energy).

- This can only happen with the default context. But since that one's
  pinned we'll never call down into evict_everything under normal
  circumstances. Note that there's a little driver bringup fun
  involved namely that we could recourse into do_switch for the
  initial switch. Atm we're fine since we assign the context pointer
  only after the call to do_switch at driver load or resume time. And
  in the gpu reset case we skip the entire setup sequence (which might
  be a bug on its own, but definitely not this one here).

Cc'ing stable since apparently ChromeOS guys are seeing this in the
wild (and not just on artificial stress tests), see the reference.

Note that in upstream code doesn't calle evict_everything directly
from evict_something, that's an extension in this product branch. But
we can still hit upon this bug (and apparently we do, see the linked
backtraces). I've noticed this while trying to construct a testcase
for this bug and utterly failed to provoke it. It looks like we need
to driver the system squarly into the lowmem wall and provoke the
shrinker to evict the context object by doing the last-ditch
evict_everything call.

Aside: There's currently no means to get a badly-fragmenting hw
context object away from a bad spot in the upstream code. We should
fix this by at least adding some code to evict_something to handle hw
contexts.

References: https://code.google.com/p/chromium/issues/detail?id=248191
Reported-by: Ian Lister <ian.lister@intel.com>
Cc: Ian Lister <ian.lister@intel.com>
Cc: stable@vger.kernel.org
Cc: Ben Widawsky <benjamin.widawsky@intel.com>
Cc: Stéphane Marchesin <marcheu@chromium.org>
Cc: Bloomfield, Jon <jon.bloomfield@intel.com>
Tested-by: Rafael Barbalho <rafael.barbalho@intel.com>
Reviewed-by: Ian Lister <ian.lister@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-12-06 13:09:11 +01:00
Chris Wilson 0d1430a3f4 drm/i915: Hold mutex across i915_gem_release
Inorder to serialise the closing of the file descriptor and its
subsequent release of client requests with i915_gem_free_request(), we
need to hold the struct_mutex in i915_gem_release(). Failing to do so
has the potential to trigger an OOPS, later with a use-after-free.

Testcase: igt/gem_close_race
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=70874
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=71029
Reported-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-12-04 16:57:02 +01:00
Ben Widawsky 2f88542607 drm/i915: Remove defunct ctx switch comments
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-11-26 10:12:16 +01:00
Daniel Vetter c09cd6e969 Merge branch 'backlight-rework' into drm-intel-next-queued
Pull in Jani's backlight rework branch. This was merged through a
separate branch to be able to sort out the Broadwell conflicts
properly before pulling it into the main development branch.

Conflicts:
	drivers/gpu/drm/i915/intel_display.c

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-11-15 10:02:39 +01:00
Ben Widawsky 8897644a6d drm/i915/bdw: HW context support
BDW context sizes varies a bit.

v2: Squash in fixup for the hw context size from Ben.

Signed-off-by: Ben Widawsky <ben@bwidawsk.net> (v1)
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-11-08 18:09:37 +01:00
Ben Widawsky 8245be3139 drm/i915: Require HW contexts (when possible)
v2: Fixed the botched locking on init_hw failure in i915_reset (Ville)
Call cleanup_ringbuffer on failed context create in init_hw (Ville)

v3: Add dev argument ti clean_ringbuffer

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-11-07 09:35:44 +01:00
Ben Widawsky 71b76d004f drm/i915: cleanup context fini
I had this lying around from he original PPGTT series, and thought we
might try to get it in by itself.

With the introduction of context refcounting we never explicitly
ref/unref the backing object. As such, the previous fix was a bit wonky.

Aside from fixing the above, this patch also puts us in good shape for
an upcoming patch which allows a failure to occur in between
context_init and the first do_switch.

CC: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-10-16 11:08:30 +02:00
Ben Widawsky e2d05a8b1e drm/i915: Convert active API to VMA
Even though we track object activity and not VMA, because we have the
active_list be based on the VM, it makes the most sense to use VMAs in
the APIs.

NOTE: Daniel intends to eventually rip out active/inactive LRUs, but for
now, leave them be.

v2: Remove leftover hunk from the previous patch which didn't keep
i915_gem_object_move_to_active. That patch had to rely on the ring to
get the dev instead of the obj. (Chris)

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-10-01 07:45:21 +02:00
Ben Widawsky 3ccfd19dea drm/i915: Do remaps for all contexts
On both Ivybridge and Haswell, row remapping information is saved and
restored with context. This means, we never actually properly supported
the l3 remapping because our sysfs interface is asynchronous (and not
tied to any context), and the known faulty HW would be reused by the
next context to run.

Not that due to the asynchronous nature of the sysfs entry, there is no
point modifying the registers for the existing context. Instead we set a
flag for all contexts to load the correct remapping information on the
next run. Interested clients can use debugfs to determine whether or not
the row has been remapped.

One could propose at this point that we just do the remapping in the
kernel. I guess since we have to maintain the sysfs interface anyway,
I'm not sure how useful it is, and I do like keeping the policy in
userspace; (it wasn't my original decision to make the
interface the way it is, so I'm not attached).

v2: Force a context switch when we have a remap on the next switch.
(Ville)
Don't let userspace use the interface with disabled contexts.

v3: Don't force a context switch, just let it nop
Improper context slice remap initialization, 1<<1 instead of 1<<i, but I
rewrote it to avoid a second round of confusion.
Error print moved to error path (All Ville)
Added a comment on why the slice remap initialization happens.

CC: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-09-19 20:39:56 +02:00
Ben Widawsky a33afea5ff drm/i915: Keep a list of all contexts
I have implemented this patch before without creating a separate list
(I'm having trouble finding the links, but the messages ids are:
<1364942743-6041-2-git-send-email-ben@bwidawsk.net>
<1365118914-15753-9-git-send-email-ben@bwidawsk.net>)

However, the code is much simpler to just use a list and it makes the
code from the next patch a lot more pretty.

As you'll see in the next patch, the reason for this is to be able to
specify when a context needs to get L3 remapping. More details there.

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-09-19 20:39:43 +02:00
Damien Lespiau 508842a036 drm/i915: It's its!
Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Acked-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-09-04 17:34:54 +02:00
Chris Wilson c0321e2c5a drm/i915: Do not add an interrupt for a context switch
We use the request to ensure we hold a reference to the context for the
duration that it remains in use by the ring. Each request only holds a
reference to the current context, hence we emit a request after
switching contexts with the final reference to the old context. However,
the extra interrupt caused by that request is not useful (no timing
critical function will wait for the context object), instead the overhead
of servicing the IRQ shows up in some (lightweight) benchmarks. In order
to keep the useful property of using the request to manage the context
lifetime, we want to add a dummy request that is associated with the
interrupt from the subsequent real request following the batch.

The extra interrupt was added as a side-effect of using
i915_add_request() in

commit 112522f678
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date:   Thu May 2 16:48:07 2013 +0300

    drm/i915: put context upon switching

v2: Daniel convinced me that the request here was solely for context
lifetime tracking and that we have the active ref to keep the object
alive whilst the MI_SET_CONTEXT. So the only concern then is which
context should get the blame for MI_SET_CONTEXT failing. The old scheme
added a request for the old context so that any hang upto and including
the switch away would mark the old context as guilty. Now any hang here
implicates the new context. However since we have already gone through a
complete flush with the last context in its last request, and all that
lies in no-man's-land is an invalidate flush and the MI_SET_CONTEXT, we
should be safe in not unduly placing blame on the new context.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Ben Widawsky <ben@bwidawsk.net>
Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-09-04 17:34:53 +02:00
Ben Widawsky ca191b1313 drm/i915: mm_list is per VMA
formerly: "drm/i915: Create VMAs (part 5) - move mm_list"

The mm_list is used for the active/inactive LRUs. Since those LRUs are
per address space, the link should be per VMx .

Because we'll only ever have 1 VMA before this point, it's not incorrect
to defer this change until this point in the patch series, and doing it
here makes the change much easier to understand.

Shamelessly manipulated out of Daniel:
"active/inactive stuff is used by eviction when we run out of address
space, so needs to be per-vma and per-address space. Bound/unbound otoh
is used by the shrinker which only cares about the amount of memory used
and not one bit about in which address space this memory is all used in.
Of course to actual kick out an object we need to unbind it from every
address space, but for that we have the per-object list of vmas."

v2: only bump GGTT LRU in i915_gem_object_set_to_gtt_domain (Chris)

v3: Moved earlier in the series

v4: Add dropped message from v3

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
[danvet: Frob patch to apply and use vma->node.size directly as
discused with Ben. Also drop a needles BUG_ON before move_to_inactive,
the function itself has the same check.]
[danvet 2nd: Rebase on top of the lost "drm/i915: Cleanup more of VMA
in destroy", specifically unlink the vma from the mm_list in
vma_unbind (to keep it symmetric with bind_to_vm) instead of
vma_destroy.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-08-08 14:06:58 +02:00
Chris Wilson 350ec881d9 drm/i915: Rename I915_CACHE_MLC_LLC to L3_LLC for Ivybridge
MLC_LLC was never validated for Sandybridge and was superseded by a new
level of cacheing for the GPU in Ivybridge. Update our names to be
consistent with usage, and in the process stop setting the unwanted bit
on Sandybridge.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
[danvet: s/BUG/WARN_ON(1) bikeshed.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-08-06 16:35:30 +02:00
Ben Widawsky c37e220461 drm/i915: Add VM to pin
To verbalize it, one can say, "pin an object into the given address
space." The semantics of pinning remain the same otherwise.

Certain objects will always have to be bound into the global GTT.
Therefore, global GTT is a special case, and keep a special interface
around for it (i915_gem_obj_ggtt_pin).

v2: s/i915_gem_ggtt_pin/i915_gem_obj_ggtt_pin

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-08-05 19:04:09 +02:00
Chris Wilson 11fa338404 drm/i915: Fix retrieval of hangcheck stats
The default context is always supported (as it contains the global
hangcheck stats) and the contexts for hangcheck are not limited
to any ring.

References: https://bugs.freedesktop.org/show_bug.cgi?id=65845
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-07-16 10:40:25 +02:00
Ben Widawsky f343c5f647 drm/i915: Getter/setter for object attributes
Soon we want to gut a lot of our existing assumptions how many address
spaces an object can live in, and in doing so, embed the drm_mm_node in
the object (and later the VMA).

It's possible in the future we'll want to add more getter/setter
methods, but for now this is enough to enable the VMAs.

v2: Reworked commit message (Ben)
Added comments to the main functions (Ben)
sed -i "s/i915_gem_obj_set_color/i915_gem_obj_ggtt_set_color/" drivers/gpu/drm/i915/*.[ch]
sed -i "s/i915_gem_obj_bound/i915_gem_obj_ggtt_bound/" drivers/gpu/drm/i915/*.[ch]
sed -i "s/i915_gem_obj_size/i915_gem_obj_ggtt_size/" drivers/gpu/drm/i915/*.[ch]
sed -i "s/i915_gem_obj_offset/i915_gem_obj_ggtt_offset/" drivers/gpu/drm/i915/*.[ch]
(Daniel)

v3: Rebased on new reserve_node patch
Changed DRM_DEBUG_KMS to actually work (will need fixing later)

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-07-08 22:04:34 +02:00
Ben Widawsky a0de80a0e0 drm/i915: Fix context sizes on HSW
With updates to the spec, we can actually see the context layout, and
how many dwords are allocated. That table suggests we need 70720 bytes
per HW context. Rounded up, this is 18 pages. Looking at what lives
after the current 4 pages we use, I can't see too much important (mostly
it's d3d related), but there are a couple of things which look scary. I
am hopeful this can explain some of our odd HSW failures.

v2: Make the context only 17 pages. The power context space isn't used
ever, and execlists aren't used in our driver, making the actual total
66944 bytes.

v3: Add a comment to the code. (Jesse & Paulo)

Reported-by: "Azad, Vinit" <vinit.azad@intel.com>
Cc: stable@vger.kernel.org
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-07-01 11:14:54 +02:00
Mika Kuoppala 0025c0772d drm/i915: change i915_add_request to macro
Only execbuffer needed all the parameters on i915_add_request().
By putting __i915_add_request behind macro, all current callsites
become cleaner. Following patch will introduce a new parameter
for __i915_add_request. With this patch, only the relevant callsite
will reflect the change making commit smaller and easier to understand.

v2: _i915_add_request as function name (Chris Wilson)

v3: change name __i915_add_request and fix ordering of params (Ben Widawsky)

Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-06-13 17:42:15 +02:00
Mika Kuoppala c0bb617a70 drm/i915: add i915_gem_context_get_hang_stats()
To get context hang statistics for specified context,
add i915_gem_context_get_hang_stats().

For arb-robustness, every context needs to have its own
hang statistics tracking. Added function will return
the user specified context statistics or in case of
default context, statistics from drm_i915_file_private.

v2: handle default context inside get_reset_state

v3: return struct pointer instead of passing it in as param
    (Chris Wilson)

Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-06-13 17:42:15 +02:00
Ben Widawsky bb0364130f drm/i915: context debug messages
Add some debug messages to help figure out what goes wrong on context
initialization.

Later in the PPGTT series, I ended up having a lot of failures after
reset. In many cases it was extra difficult to debug because I hadn't
even realized that contexts failed to reinitialize after reset (again an
artifact of some later patches).

This fairly benign patch does help debug some potential issues which
arise later.

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-05-31 20:53:58 +02:00
Damien Lespiau 8693a82487 drm/i915: Add references to some workaround we implement
We did not mention the workaround name when implementing those. This
should help us track what we already implement.

Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-05-10 21:56:34 +02:00
Ben Widawsky 186507e9e8 drm/i915: Assert mutex_is_locked on context lookup
Because our context refcounting doesn't grab a ref at lookup time, it is
unsafe to do so without the lock.

NOTE: We don't have an easy way to put the assertion in the lookup
function which is where this really belongs. Context switching is good
enough because it actually asserts even more correctness by protecting
the default_context.

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
[danvet: s/BUG/WARN/]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-05-06 11:30:29 +02:00
Chris Wilson 112522f678 drm/i915: put context upon switching
In order to be notified of when the context and all of its associated
objects is idle (for if the context maps to a ppgtt) we need a callback
from the retire handler. We can arrange this by using the kref_get/put
of the context for request tracking and by inserting a request to
demarque the switch away from the old context.

[Ben: fixed minor error to patch compile, AND s/last_context/from/]
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-05-06 11:20:48 +02:00
Mika Kuoppala 168f836602 drm/i915: unreference default context on module unload
Before module unload is called, gpu_idle() will switch
to default context. This will increment ref count of base
object as the default context is 'running' on module unload
time. Unreference the drm object so that when context
is freed, base object is freed as well.

v2: added comment to explain the refcounts (Ben Widawsky)

Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-05-03 18:19:56 +02:00
Mika Kuoppala dce3271b1e drm/i915: reference count for i915_hw_contexts
Enabling PPGTT and also the need to track which context was guilty of
gpu hang (arb robustness enabling) have put pressure for struct i915_hw_context
to be more than just a placeholder for hw context state.

In order to track object lifetime properly in a multi peer usage, add reference
counting for i915_hw_context.

v2: track i915_hw_context pointers instead of using ctx_ids
(from Chris Wilson)

v3 (Ben): Get rid of do_release() and handle refcounting more compactly.
(recommended by Chis)

v4: kref_* put inside static inlines (Daniel Vetter)
remove code duplication on freeing context (Chris Wilson)

v5: idr_remove and ctx->file_priv = NULL in destroy ioctl (Chris)
This actually will cause a problem if one destroys a context and later
refers to the idea of the context (multiple contexts may have the same
id, but only 1 will exist in the idr).

v6: Strip out the request related stuff. Reworded commit message.
Got rid of do_destroy and introduced i915_gem_context_release_handle,
suggested by Chris Wilson.

v7: idr_remove can't be called inside idr_for_each (Chris Wilson)

Signed-off-by: Ben Widawsky <ben@bwidawsk.net> (v5)
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com> (v7)
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
[danvet: Squash sob lines, the patch ping-ponged between Ben and Mika
a bit ...]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-04-30 23:40:13 +02:00
Chris Wilson 4615d4c9e2 drm/i915: Use MLC (l3$) for context objects
Enabling context support increases SwapBuffers latency by about 20%
(measured on an i7-3720qm). We can offset that loss slightly by enabling
faster caching for the contexts. As they are not backed by any
particular cache (such as the sampler or render caches) our only option
is to select the generic mid-level cache. This reduces the latency of
the swap by about 5%.

Oddly this effect can be observed running smokin-guns on IVB at
1280x1024:
Using BLT copies for swaps: 151.67 fps
Using Render copies for swaps (unpatched):  141.70 fps
With contexts disabled: 150.23 fps
With contexts in L3$: 150.77 fps

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Ben Widawsky <ben@bwidawsk.net>
Cc: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-04-18 09:43:11 +02:00
Tejun Heo c8c470afe3 drm/i915: convert to idr_alloc()
Convert to the much saner new idr interface.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: David Airlie <airlied@linux.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-27 19:10:16 -08:00
Ben Widawsky f73f760725 drm/i915/ctx: Remove bad invariant
It's not that the assertion is incorrect, but rather that we can call
do_destroy early in loading, and we will falsely BUG().

Since contexts have been in for a while now, and in the internal APIs
are pretty stable, it should be fairly safe to remove this.

v2: Remove unused dev_priv, and dev

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-02-15 10:30:40 +01:00
Ben Widawsky 07ea0d85ac drm/i915: Clarify HW context size logic
This was a rebase error from when the patches originally landed. Since
the context size is unsigned, there is also no use in checking if it's
less than 0.

The existing code is not really wrong, but it's not simple as it should
be.

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-02-15 10:30:36 +01:00
Chris Wilson 9d7730914f drm/i915: Preallocate next seqno before touching the ring
Based on the work by Mika Kuoppala, we realised that we need to handle
seqno wraparound prior to committing our changes to the ring. The most
obvious point then is to grab the seqno inside intel_ring_begin(), and
then to reuse that seqno for all ring operations until the next request.
As intel_ring_begin() can fail, the callers must already be prepared to
handle such failure and so we can safely add further checks.

This patch looks like it should be split up into the interface
changes and the tweaks to move seqno wrapping from the execbuffer into
the core seqno increment. However, I found no easy way to break it into
incremental steps without introducing further broken behaviour.

v2: Mika found a silly mistake and a subtle error in the existing code;
inside i915_gem_retire_requests() we were resetting the sync_seqno of
the target ring based on the seqno from this ring - which are only
related by the order of their allocation, not retirement. Hence we were
applying the optimisation that the rings were synchronised too early,
fortunately the only real casualty there is the handling of seqno
wrapping.

v3: Do not forget to reset the sync_seqno upon module reinitialisation,
ala resume.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=863861
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com> [v2]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-11-29 11:43:52 +01:00
Ben Widawsky f94982b002 drm/i915: Allocate the proper size for contexts.
Whoops. This was fixed previously, but not sure how it got lost. It's
not needed for -fixes or stable because at the moment
drm_i915_file_private is way bigger than i915_hw_context (by 120 bytes
on my 64b build).

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-11-11 23:51:47 +01:00
Dave Airlie 1f31c69dac Merge branch 'drm-intel-fixes' of git://people.freedesktop.org/~danvet/drm-intel into drm-next
Daniel writes:

Bigger -fixes pile, mostly because I've included Ajax' DP dongle stuff,
as discussed on irc. Otherwise just small things:
- regression fix to finally make 6bpc auto-dither on dp work (Jani)
- reinstate an snb ctx w/a that accidentally got lost in a rework (Chris)
- fixup the DP train sequence, logic-goof-up uncovered by Coverty (Chris)
- fix set_caching locking (Ben)
- fix spurious segfault on con-current gtt mmap faulting (Dimitry and Mika)
- some pageflip correctness fixes (still hunting down some issues, but
  these are the worst offenders of confused code that we've tracked down
  thus far) from Chris and me
- fixup swizzling settings on vlv (Jesse)
- gt_mode w/a from Ben added, fixes snb gt1 rc6+hw ctx hangs.

* 'drm-intel-fixes' of git://people.freedesktop.org/~danvet/drm-intel:
  drm/i915: Fix GT_MODE default value
  drm/i915: don't frob the vblank ts in finish_page_flip
  drm/i915: call drm_handle_vblank before finish_page_flip
  drm/i915: print warning if vmi915_gem_fault error is not handled
  drm/i915: EBUSY status handling added to i915_gem_fault().
  drm/i915: Try harder to complete DP training pattern 1
  drm/i915: set swizzling to none on VLV
  drm/dp: Make sink count DP 1.2 aware
  drm/dp: Document DP spec versions for various DPCD registers
  drm/i915/dp: Be smarter about connection sense for branch devices
  drm/i915/dp: Fetch downstream port info if needed during DPCD fetch
  drm/dp: Update DPCD defines
  drm: Export drm_probe_ddc()
  drm/i915: Flush the pending flips on the CRTC before modification
  drm/i915: Actually invalidate the TLB for the SandyBridge HW contexts w/a
  drm/i915: Fix set_caching locking
  drm/i915: use adjusted_mode instead of mode for checking the 6bpc force flag
2012-10-07 21:13:54 +10:00
Linus Torvalds 612a9aab56 Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux
Pull drm merge (part 1) from Dave Airlie:
 "So first of all my tree and uapi stuff has a conflict mess, its my
  fault as the nouveau stuff didn't hit -next as were trying to rebase
  regressions out of it before we merged.

  Highlights:
   - SH mobile modesetting driver and associated helpers
   - some DRM core documentation
   - i915 modesetting rework, haswell hdmi, haswell and vlv fixes, write
     combined pte writing, ilk rc6 support,
   - nouveau: major driver rework into a hw core driver, makes features
     like SLI a lot saner to implement,
   - psb: add eDP/DP support for Cedarview
   - radeon: 2 layer page tables, async VM pte updates, better PLL
     selection for > 2 screens, better ACPI interactions

  The rest is general grab bag of fixes.

  So why part 1? well I have the exynos pull req which came in a bit
  late but was waiting for me to do something they shouldn't have and it
  looks fairly safe, and David Howells has some more header cleanups
  he'd like me to pull, that seem like a good idea, but I'd like to get
  this merge out of the way so -next dosen't get blocked."

Tons of conflicts mostly due to silly include line changes, but mostly
mindless.  A few other small semantic conflicts too, noted from Dave's
pre-merged branch.

* 'drm-next' of git://people.freedesktop.org/~airlied/linux: (447 commits)
  drm/nv98/crypt: fix fuc build with latest envyas
  drm/nouveau/devinit: fixup various issues with subdev ctor/init ordering
  drm/nv41/vm: fix and enable use of "real" pciegart
  drm/nv44/vm: fix and enable use of "real" pciegart
  drm/nv04/dmaobj: fixup vm target handling in preparation for nv4x pcie
  drm/nouveau: store supported dma mask in vmmgr
  drm/nvc0/ibus: initial implementation of subdev
  drm/nouveau/therm: add support for fan-control modes
  drm/nouveau/hwmon: rename pwm0* to pmw1* to follow hwmon's rules
  drm/nouveau/therm: calculate the pwm divisor on nv50+
  drm/nouveau/fan: rewrite the fan tachometer driver to get more precision, faster
  drm/nouveau/therm: move thermal-related functions to the therm subdev
  drm/nouveau/bios: parse the pwm divisor from the perf table
  drm/nouveau/therm: use the EXTDEV table to detect i2c monitoring devices
  drm/nouveau/therm: rework thermal table parsing
  drm/nouveau/gpio: expose the PWM/TOGGLE parameter found in the gpio vbios table
  drm/nouveau: fix pm initialization order
  drm/nouveau/bios: check that fixed tvdac gpio data is valid before using it
  drm/nouveau: log channel debug/error messages from client object rather than drm client
  drm/nouveau: have drm debugging macros build on top of core macros
  ...
2012-10-03 23:29:23 -07:00
David Howells 760285e7e7 UAPI: (Scripted) Convert #include "..." to #include <path/...> in drivers/gpu/
Convert #include "..." to #include <path/...> in drivers/gpu/.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Dave Airlie <airlied@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Dave Jones <davej@redhat.com>
2012-10-02 18:01:07 +01:00
Chris Wilson ac82ea2e97 drm/i915: Actually invalidate the TLB for the SandyBridge HW contexts w/a
A side-effect of commit 7d54a90428
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date:   Fri Aug 10 10:18:10 2012 +0100

    drm/i915: Apply post-sync write for pipe control invalidates

was that only a request to emit invalidate flush would result in the
TLB being invalidated (since it requires synchronisation and so incurs a
performance penalty). However, the stated w/a for hardware contexts is
that the TLBs must be invalidated prior to a MI_SET_CONTEXT, yet the w/a
itself did not request the TLBs to be invalidated...

Note this w/a does not prevent the hard system hang I experience when
using hw contexts (with rc6 enabled) on SNB GT1.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-10-02 10:28:18 +02:00
Chris Wilson 86a1ee26bb drm/i915: Only pwrite through the GTT if there is space in the aperture
Avoid stalling and waiting for the GPU by checking to see if there is
sufficient inactive space in the aperture for us to bind the buffer
prior to writing through the GTT. If there is inadequate space we will
have to stall waiting for the GPU, and incur overheads moving objects
about. Instead, only incur the clflush overhead on the target object by
writing through shmem.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-08-24 02:03:33 +02:00
Devendra Naga e47e9ad918 drm/i915: remove unused variable
the following warning was produced,

drivers/gpu/drm/i915/i915_gem_context.c: In function ‘i915_switch_context’:
drivers/gpu/drm/i915/i915_gem_context.c:454:6: warning: unused variable ‘ret’ [-Wunused-variable]

fix up by removing it

Signed-off-by: Devendra Naga <devendra.aaru@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-08-05 22:39:53 +02:00
Ben Widawsky 2e4291e0bc drm/i915: Add contexts for HSW
Basic context support on HSW is no different than previous generations.
The size of the context object changes, but that's about it.

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-07-25 18:23:56 +02:00
Chris Wilson 9a3b530455 drm/i915: Cleanup context switching through do_switch()
When bug hunting, I found the interface to do_switch() overly
complicated and I believe festered the earlier bug. This aims to make
the code a little clearer.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-07-25 18:23:45 +02:00
Dan Carpenter be636387f8 drm/i915: dereferencing an error pointer
We need to check that "ctx" is a valid pointer before dereferencing it.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-07-25 10:39:58 +02:00
Chris Wilson b259b31206 drm/i915: fix invalid reference handling of the default ctx obj
Otherwise we end up trying to unpin a freed object and BUG.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-07-25 10:39:58 +02:00
Chris Wilson d3373a241b drm/i915: Flush the context object from the CPU caches upon switching
The issue is that we stale data in the CPU caches, when we come to
swap-out the object, the CPU may short-circuit the reads from those
cacheline and so corrupt the context object.

Secondary, leaving the context object as being marked in the CPU write
domain whilst on the GPU active list is a bad idea and will throw
warnings later.

Note: Thanks to calling set_to_gtt_domain with write = false and not
setting any gpu write domain when putting a context object onto the
active list (when we switch away from it) the set_to_gtt_domain call
won't block.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
[danvet: Added a note to the commit message and a comment in the code
to explain the clever non-blocking trick.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-07-25 10:39:57 +02:00
Ben Widawsky 4f91dd6f27 drm/i915/context/: s/CTX/CXT
*sigh* the docs had it spelled wrong, corrected it, and then proceeded
to re-do the original error. The original code preserved this history,
and this patch attempts to keep in sync with the current docs.

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-07-20 12:21:35 +02:00
Ben Widawsky 146937e582 drm/i915: linuxify create_hw_context()
Daniel complained about this on initial review, but he graciously moved
the patches forward. As promised, I am delivering the desired cleanup
now.

Hopefully I didn't screw the trivial patch up ;-)

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-06-29 19:43:59 +02:00
Daniel Vetter 5fa8be65e9 drm/i915: return -ENODEV if hw context are not supported
Otherwise userspace has no way to figure this out.

Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-06-20 11:19:20 +02:00
Daniel Vetter 73c273eb75 drm/i915: simplify context_idr_cleanup
The idr code already passes us the pointer associated with that id, so
no need to look it up again. Also, we'll kill the idr right away, so
there's no issue with leaving these dangling pointers behind - the
current code does the same.

v2: Also drop the file argument, spotted by Ben Widawsky.

Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-06-20 11:16:48 +02:00
Daniel Vetter 6f4c45c12c drm/i915/context: shut up compiler
It found some unused variables.

Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-06-20 11:16:28 +02:00
Daniel Vetter 0d32601376 drm/i915: return -ENOENT if the context doesn't exist
This is our customary "no such object" errno, not -EINVAL.

Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-06-20 11:16:08 +02:00
Daniel Vetter df12c6d5ec drm/i915: initialize the context idr unconditionally
It doesn't hurt and it at least prevents us from OOPSing left and
right at quite a few places. This also allows us to simplify the code
a bit by folding the only line of context_open into the callsite.

We obviuosly also need to run the cleanup code unconditionally, too.

Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-06-20 11:15:37 +02:00
Daniel Vetter 55a6662837 drm/i915: fix module unload after context merge
commit 8e96d9c4d9
Author: Ben Widawsky <ben@bwidawsk.net>
Date:   Mon Jun 4 14:42:56 2012 -0700

    drm/i915: reset the GPU on context fini

broke module unload because it reset the gpu before we've stopped
touching it. Later on in the unload sequence the ringbuffer code
complained that the gpu would idle properly (because intel_gpu_reset
only resets the hw and not our sw state).

v2: Reorder things so that we reset the gpu _before_ we release the
backing storage of the default context.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=51183
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-06-20 10:06:29 +02:00
Ben Widawsky e158c5aa17 drm/i915: disable contexts on old HW
This got dropped as a result of the last round of comments. I didn't
test it on unsupported HW (which this is likely the case).

Note that this prevents hw context from blowing up on any pre-gen6 hw.

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=51142
[danvet: Added note and buglink.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-06-18 10:01:08 +02:00
Ben Widawsky 8e96d9c4d9 drm/i915: reset the GPU on context fini
It's the only way we know how to make the GPU actually forget about the
default context.

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
2012-06-14 17:36:21 +02:00
Ben Widawsky 846248136d drm/i915/context: create & destroy ioctls
Add the interfaces to allow user space to create and destroy contexts.
Contexts are destroyed automatically if the file descriptor for the dri
device is closed.

Following convention as usual here causes checkpatch warnings.

v2: with is_initialized, no longer need to init at create
drop the context switch on create (daniel)

v3: Use interruptible lock (Chris)
return -ENODEV in !GEM case (Chris)

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
2012-06-14 17:36:20 +02:00
Ben Widawsky dfabbcb4f6 drm/i915: use the default context
With the code to do HW context switches in place have the driver load the
default context for the render ring when the driver loads.

The default context will be an ever present context that is available to
switch to at any time for the given ring.

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
2012-06-14 17:36:19 +02:00
Ben Widawsky 12b0286f49 drm/i915: possibly invalidate TLB before context switch
From http://intellinuxgraphics.org/documentation/SNB/IHD_OS_Vol1_Part3.pdf

[DevSNB] If Flush TLB invalidation Mode is enabled it's the driver's
responsibility to invalidate the TLBs at least once after the previous
context switch after any GTT mappings changed (including new GTT
entries).  This can be done by a pipelined PIPE_CONTROL with TLB inv bit
set immediately before MI_SET_CONTEXT.

On GEN7 the invalidation mode is explicitly set, but this appears to be
lacking for GEN6. Since I don't know the history on this, I've decided
to dynamically read the value at ring init time, and use that value
throughout.

v2: better comment (daniel)

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
2012-06-14 17:36:19 +02:00
Ben Widawsky e37ec39b18 drm/i915: Ivybridge MI_ARB_ON_OFF context w/a
The workaround itself applies to gen7 only (according to the docs) and
as Eric Anholt points out shouldn't be required since we don't use HW
scheduling features, and therefore arbitration. Though since it is a
small, and simple addition, and we don't really understand the issue,
just do it.

FWIW, I eventually want to play with some of the arbitration stuff, and
I'd hate to forget about this.

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
2012-06-14 17:36:18 +02:00
Daniel Vetter 3af7b8572f drm/i915: ensure context objects are bound to the global gtt
This way round we don't introduce and ugly layering violations and use
the interface as I planned to use it.

Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-06-14 17:36:17 +02:00
Ben Widawsky e055684168 drm/i915: context switch implementation
Implement the context switch code as well as the interfaces to do the
context switch. This patch also doesn't match 1:1 with the RFC patches.
The main difference is that from Daniel's responses the last context
object is now stored instead of the last context. This aids in allows us
to free the context data structure, and context object independently.

There is room for optimization: this code will pin the context object
until the next context is active. The optimal way to do it is to
actually pin the object, move it to the active list, do the context
switch, and then unpin it. This allows the eviction code to actually
evict the context object if needed.

The context switch code is missing workarounds, they will be implemented
in future patches.

v2: actually do obj->dirty=1 in switch (daniel)
Modified comment around above
Remove flags to context switch (daniel)
Move mi_set_context code to i915_gem_context.c (daniel)
Remove seqno , use lazy request instead (daniel)

v3: use i915_gem_request_next_seqno instead of
      outstanding_lazy_request (Daniel)
remove id's from trace events (Daniel)
Put the context BO in the instruction domain (Daniel)
Don't unref the BO is context switch fails (Chris)

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
2012-06-14 17:36:17 +02:00
Ben Widawsky 40521054fd drm/i915: context basic create & destroy
Invent an abstraction for a hw context which is passed around through
the core functions. The main bit a hw context holds is the buffer object
which backs the context. The rest of the members are just helper
functions. Specifically the ring member, which could likely go away if
we decide to never implement whatever other hw context support exists.

Of note here is the introduction of the 64k alignment constraint for the
BO. If contexts become heavily used, we should consider tweaking this
down to 4k. Until the contexts are merged and tested a bit though, I
think 64k is a nice start (based on docs).

Since we don't yet switch contexts, there is really not much complexity
here. Creation/destruction works pretty much as one would expect. An idr
is used to generate the context id numbers which are unique per file
descriptor.

v2: add DRM_DEBUG_DRIVERS to distinguish ENOMEM failures (ben)
convert a BUG_ON to WARN_ON, default destruction is still fatal (ben)

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
2012-06-14 17:36:16 +02:00
Ben Widawsky 254f965c39 drm/i915: preliminary context support
Very basic code for context setup/destruction in the driver.

Adds the file i915_gem_context.c This file implements HW context
support. On gen5+ a HW context consists of an opaque GPU object which is
referenced at times of context saves and restores.  With RC6 enabled,
the context is also referenced as the GPU enters and exists from RC6
(GPU has it's own internal power context, except on gen5).  Though
something like a context does exist for the media ring, the code only
supports contexts for the render ring.

In software, there is a distinction between contexts created by the
user, and the default HW context. The default HW context is used by GPU
clients that do not request setup of their own hardware context. The
default context's state is never restored to help prevent programming
errors. This would happen if a client ran and piggy-backed off another
clients GPU state.  The default context only exists to give the GPU some
offset to load as the current to invoke a save of the context we
actually care about. In fact, the code could likely be constructed,
albeit in a more complicated fashion, to never use the default context,
though that limits the driver's ability to swap out, and/or destroy
other contexts.

All other contexts are created as a request by the GPU client. These
contexts store GPU state, and thus allow GPU clients to not re-emit
state (and potentially query certain state) at any time. The kernel
driver makes certain that the appropriate commands are inserted.

There are 4 entry points into the contexts, init, fini, open, close.
The names are self-explanatory except that init can be called during
reset, and also during pm thaw/resume. As we expect our context to be
preserved across these events, we do not reinitialize in this case.

As Adam Jackson pointed out, The cutoff of 1MB where a HW context is
considered too big is arbitrary. The reason for this is even though
context sizes are increasing with every generation, they have yet to
eclipse even 32k. If we somehow read back way more than that, it
probably means BIOS has done something strange, or we're running on a
platform that wasn't designed for this.

v2: rename load/unload to init/fini (daniel)
remove ILK support for get_size() (indirectly daniel)
add HAS_HW_CONTEXTS macro to clarify supported platforms (daniel)
added comments (Ben)

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
2012-06-14 17:36:16 +02:00