The code to handle it is broken - there's simply no code to clear CS
parser errors on gen5+. And behold, for all the other rings we also
don't enable it!

Leave the handling code itself in place just to be consistent with the
existing mess though. And in case someone feels like fixing it all up.

This has been errornously enabled in

commit 12638c57
Author: Ben Widawsky <ben@bwidawsk.net>
Date:   Tue May 28 19:22:31 2013 -0700

    drm/i915: Enable vebox interrupts

Cc: Damien Lespiau <damien.lespiau@intel.com>
Cc: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

With the simplified locking there's no reason any more to keep the
refcounts seperate.

v2: Readd the lost comment that ring->irq_refcount is protected by
dev_priv->irq_lock.
Reviewed-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Now that the rps interrupt locking isn't clearly separated (at elast
conceptually) from all the other interrupt locking having a different
lock stopped making sense: It protects much more than just the rps
workqueue it started out with. But with the addition of VECS the
separation started to blurr and resulted in some more complex locking
for the ring interrupt refcount.

With this we can (again) unifiy the ringbuffer irq refcounts without
causing a massive confusion, but that's for the next patch.

v2: Explain better why the rps.lock once made sense and why no longer,
requested by Ben.
Reviewed-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

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: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

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: NMika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Acked-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

When we reset and restart a ring, we also want to clear any existing
hangcheck.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NMika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

WaFbcNukeOn3DBlt for IVB, HSW.

According BSPec: "Workaround: Do not enable Render Command Streamer tracking for FBC.
Instead insert a LRI to address 0x50380 with data 0x00000004 after the PIPE_CONTROL that
follows each render submission."

v2: Chris noticed that flush_domains check was missing here and also suggested to do
    LRI only when fbc is enabled. To avoid do a I915_READ on every flush lets use the
    module parameter check.

v3: Adding Wa name as Damien suggested.

v4: Ville noticed VLV doesn't support fbc at all and comment came wrong from spec.

v5: Ville noticed than on blt a Cache Clean LRI should be used instead the Nuke one.

v6: Check for flush domain on blt (by Ville).
    Check for scanout dirty (by Chris).

v7: Apply proper fbc_dirty implemented by Chris.

v8: remove unused variables.

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NRodrigo Vivi <rodrigo.vivi@gmail.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Similar to a patch originally written by:

v2: Reversed the meanings of masked and enabled (Haihao)
Made non-destructive writes in case enable/disabler rps runs first
(Haihao)

v3: Reword error message (Damien)
Modify postinstall to do the right thing based on previous fixup. (Ben)

CC: Xiang, Haihao <haihao.xiang@intel.com>
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

v2: Use the correct lock to protect PM interrupt regs, this was
accidentally lost from earlier (Haihao)
Fix return types (Ben)
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The motivation here is we're going to add some new interrupt definitions
and handling outside of the GT interrupts which is all we've managed so
far (with some RPS exceptions). By consolidating the names in the future
we can make thing a bit cleaner as we don't need to define register
names twice, and we can leverage pretty decent overlap in HW registers
since ILK.

To explain briefly what is in the comments: there are two sets of
interrupt masking/enabling registers. At least so far, the definitions
of the two sets overlap. The old code setup distinct names for
interrupts in each set, ie. one for global, and one for ring. This made
things confusing when using the wrong defines in the wrong places.

rebase: Modified VLV bits

v2: Renamed GT_RENDER_MASTER to GT_RENDER_CS_MASTER (Damien)
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

It's overkill on older gens, but it's useful for newer gens.
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

v2: Add set_seqno which didn't exist before rebase (Haihao)
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NXiang, Haihao <haihao.xiang@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Historically we considered the render ring to have special flush
semantics and everything else to fall under a more general umbrella.
Probably by coincidence more than anything we decided to make the bsd
ring have the default *other* flush. As the new vebox ring exposes, the
bsd ring is actually the weird one. Doing this allows us to call
gen6_ring_flush for the vebox because calling blt_ring_flush would be
weird...

This patch should have no functional change.
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Like the other rings, the VECS supports semaphores. The semaphore stuff
is a bit wonky so this patch on it's own should be nice for review.

This patch should have no functional impact.

v2: Fix the English parts of clarification (again, register names were
right, text was reversed) (Damien)
Restore the still valid invariant. (Damien)
The bsd semaphore register should be MI_SEMAPHORE_SYNC_VVE (Damien)
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The video enhancement command streamer is a new ring on HSW which does
what it sounds like it does. This patch provides the most minimal
inception of the ring.

In order to support a new ring, we need to bump the number. The patch
may look trivial to the untrained eye, but bumping the number of rings
is a bit scary. As such the patch is not terribly useful by itself, but
a pretty nice place to find issues during a bisection.
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This replaces the existing MBOX update code with a more generalized
calculation for emitting mbox updates. We also create a sentinel for
doing the updates so we can more abstractly deal with the rings.

When doing MBOX updates the code must be aware of the /other/ rings.
Until now the platforms which supported semaphores had a fixed number of
rings and so it made sense for the code to be very specialized
(hardcoded).

The patch does contain a functional change, but should have no
behavioral changes.
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Semaphores are tied very closely to the rings in the GPU. Trivial patch
adds comments to the existing code so that when we add new rings we can
include comments there as well. It also helps distinguish the ring to
semaphore mailbox interactions by using the ringname in the semaphore
data structures.

This patch should have no functional impact.

v2: The English parts (as opposed to register names) of the comments
were reversed. (Damien)
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Fix to return -ENOMEM in the kmap() error handling case
instead of 0, as done elsewhere in this function.
Signed-off-by: NWei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Instead of relying in acthd, track ring seqno progression
to detect if ring has hung.

v2: put hangcheck stuff inside struct (Chris Wilson)

v3: initialize hangcheck.seqno (Ben Widawsky)
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We did not mention the workaround name when implementing those. This
should help us track what we already implement.
Signed-off-by: NDamien Lespiau <damien.lespiau@intel.com>
Reviewed-by: NImre Deak <imre.deak@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The bit controlling whether PIPE_CONTROL DW/QW write targets
the global GTT or PPGTT moved moved from DW 2 bit 2 to
DW 1 bit 24 on IVB.

I verified on IVB that the fix is in fact effective. Without the fix
none of the scratch writes actually landed in the pipe control page.
With the fix the writes show up correctly.

v2: move PIPE_CONTROL_GLOBAL_GTT_IVB setup to where other flags are set
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We already print the HWS addresses during init, so do the same for the
pipe control page. Reduces guesswork when looking at hex addresses
later.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

On SNB, if bit 13 of GFX_MODE, Flush TLB Invalidate Mode, is not set to 1,
the hardware can not program the scanline values. Those scanline values
then control when the signal is sent from the display engine to the render
ring for MI_WAIT_FOR_EVENTs. Note setting this bit means that TLB
invalidations must be performed explicitly through the appropriate bits
being set in PIPE_CONTROL.

References: https://bugzilla.kernel.org/show_bug.cgi?id=52311Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: stable@vger.kernel.org
Reviewed-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This is a required workarounds for all products, especially on gen6+
where it causes the command streamer to fail to parse instructions
following a WAIT_FOR_EVENT. We use WAIT_FOR_EVENT for synchronising
between the GPU and the display engines, and so this bit being unset may
cause hangs.

References: https://bugzilla.kernel.org/show_bug.cgi?id=52311Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: stable@vger.kernel.org
Reviewed-by: NImre Deak <imre.deak@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

When machine was rebooted or module was reloaded,
gem_hw_init() set last_seqno to be identical to next_seqno.
This lead to situation that waits for first ever request
always passed immediately regardless if it was actually
executed.

Use gem_set_seqno() to be consistent how hw is
initialized on init, wrap and on resume.
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

And to make Ben Widawsky happier, use the gpu_error instead of
the entire device as the argument in some functions.

Drop the outdated comment on ->wedged for now, a follow-up patch will
change the semantics and add a proper comment again.
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This has been sprinkled all over the place in dev_priv. I think
it'd be good to also move all the code into a separate file like
i915_gem_error.c, but that's for another patch.
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We have enough info to not use the intel_gtt bridge stuff.

v2: Move setup of mappable_base above the legacy init stuff because we
still need that on older platforms. (Daniel)

v3: Remove the dev_priv hunk which was rebased in by accident

Reviewed-by: Rodrigo Vivi <rodrigo.vivi@gmail.com> (v2)
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Hardware status page needs to have proper seqno set
as our initial seqno can be arbitrary. If initial seqno is close
to wrap boundary on init and i915_seqno_passed() (31bit space)
refers to hw status page which contains zero, errorneous result
will be returned.

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

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

References: https://bugs.freedesktop.org/show_bug.cgi?id=58230Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

In preparation for setting per ring initial seqno values
add ring::set_seqno().
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Now that Chris Wilson demonstrated that the key for stability on early
gen 2 is to simple _never_ exchange the physical backing storage of
batch buffers I've tried a stab at a kernel solution. Doesn't look too
nefarious imho, now that I don't try to be too clever for my own good
any more.

v2: After discussing the various techniques, we've decided to always blit
batches on the suspect devices, but allow userspace to opt out of the
kernel workaround assume full responsibility for providing coherent
batches. The principal reason is that avoiding the blit does improve
performance in a few key microbenchmarks and also in cairo-trace
replays.
Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
[danvet:
- Drop the hunk which uses HAS_BROKEN_CS_TLB to implement the ring
  wrap w/a. Suggested by Chris Wilson.
- Also add the ACTHD check from Chris Wilson for the error state
  dumping, so that we still catch batches when userspace opts out of
  the w/a.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

If wrap just happened we need to prevent emitting waits for
pre wrap values. Detect this and emit no-ops instead.

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

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

v4: Fixed unnecessary last_seqno assigment

References: https://bugs.freedesktop.org/show_bug.cgi?id=57967Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

If there are pre-wrap values in semaphore-mbox registers after wrap,
syncing against some after-wrap request will complete immediately.
Fix this by emitting ring commands to set mbox registers to zero
when the wrap happens.

v2: Use __intel_ring_begin to emit ring commands, from
Chris Wilson.
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
[danvet: Add a small comment to handle_seqno_wrap.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

In preparation for handling ring seqno wrapping, split
intel_ring_begin into helper part which doesn't allocate
seqno.
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

From BSpec:
"If the Ring Buffer Head Pointer and the Tail Pointer are on the same
cacheline, the Head Pointer must not be greater than the Tail
Pointer."

The easiest way to enforce this is to reduce the reported ring space.

References:
Gen2 BSpec "1. Programming Environment" / 1.4.4.6 "Ring Buffer Use"
Gen3 BSpec "vol1c Memory Interface Functions" / 2.3.4.5 "Ring Buffer Use"
Gen4+ BSpec "vol1c Memory Interface and Command Stream" / 5.3.4.5 "Ring Buffer Use"

v2: Include the exact BSpec references in the description

v3: s/64/I915_RING_FREE_SPACE, and add the BSpec information to the code
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Acked-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Replace the wait for the ring to be clear with the more common wait for
the ring to be idle. The principle advantage is one less exported
intel_ring_wait function, and the removal of a hardcoded value.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NMika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

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: NChris 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: NDaniel Vetter <daniel.vetter@ffwll.ch>

The bspec was recently updated to remove the ability to update the
semaphore using the MI_SEMAPHORE_BOX command, the ability to wait upon
the semaphore value remained. Instead the advice is to update the
register using the MI_LOAD_REGISTER_IMM command. In cursory testing,
semaphores continue to function - the question is whether this fixes
some of the deadlocks where the semaphore registers contained stale
values?
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel J Blueman <daniel@quora.org>
Reviewed-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

By always setting up the HWS register for both physical and virtual
address variations during render ring we can reduce the number of
different special cases that get set up at varying different times
during module load.

Fixes regression from

commit c630119f
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date:   Wed Oct 17 11:32:57 2012 +0200

    drm/i915: don't save/restore HWS_PGA reg for kms
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>