Our driver initialization doesn't seem to be ready to load when the
power well is disabled: we hit a few "Unclaimed register" messages. So
do just like we already do for the suspend/resume path: enable the
power well before unloading.

At some point we'll want to be able to survive suspend/resume and
load/unload with the power well disabled, but for now let's just fix
the regression.

Regression introduced by the following commit:

commit bf51d5e2
Author: Paulo Zanoni <paulo.r.zanoni@intel.com>
Date:   Wed Jul 3 17:12:13 2013 -0300
    drm/i915: switch disable_power_well default value to 1

Bug can be reproduced by running the "module_reload" script from
intel-gpu-tools.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=67813Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Makes it more obviously correct what tricks we play by reusing the drm
prime release helper.
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This fixes a WARN in i915_gem_free_object when the
obj->pages_pin_count isn't 0.

v2: Add locking to unmap, noticed by Chris Wilson. Note that even
though we call unmap with our own dev->struct_mutex held that won't
result in an immediate deadlock since we never go through the dma_buf
interfaces for our own, reimported buffers. But it's still easy to
blow up and anger lockdep, but that's already the case with our ->map
implementation. Fixing this for real will involve per dma-buf ww mutex
locking by the callers. And lots of fun. So go with the duct-tape
approach for now.

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reported-by: NMaarten Lankhorst <maarten.lankhorst@canonical.com>
Cc: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Tested-by: Armin K. <krejzi@email.com> (v1)
Acked-by: NMaarten Lankhorst <maarten.lankhorst@canonical.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Un-masking all PM interrupts causes hardware to generate
interrupts regardless of whether the interrupts are enabled
on the DE side. Since turbo only need up/down threshold and
rc6 timeout interrupt, mask all other interrupts bits to avoid
unnecessary overhead/wake up.

Note that our interrupt handler isn't being fired since we do set the
IER bits properly (IIR bits aren't set). The overhead isn't because
our driver is reacting to these interrupts, but because hardware keeps
generating internal messages when PMINTRMSK doesn't mask out the
up/down EI interrupts (which happen periodically).

Change-Id: I6c947df6fd5f60584d39b9e8b8c89faa51a5e827
Signed-off-by: NVinit Azad <vinit.azad@intel.com>
[danvet: Add follow-up explanation of the precise effects from Vinit
as a note to the commit message.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Whenever I need to work with the HSW_PWER_WELL_* register bits I have
to look at the documentation to find out which bit is to request the
power well and which one shows its current state. Rename the bits so I
won't need to look the docs every time.
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

If the power well is disabled VGA is guaranteed to be disabled.

This fixes unclaimed register messages that happen on suspend/resume.

v2: Check the actual hw power well state instead of our own tracking
to make sure VGA is _really_ off (in case the BIOS/KVMr has just its
own request bit set). Requested by Ville.

Note: Ville suggested whether it wouldn't be better to just enable the
power well over a slightly longer time in our resume code, since we
already do that. I tend to agree, but there's also the modeset force
code in the lid notifier which _also_ eventually calls redisable_vga.
We shouldn't ever need this on somewhat modern hw (everything with
opregion essentially) but the code to bail out isn't there. Hence
stick with this simple approach here for now.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=67517Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
[danvet: Summarize the discussion around the resume sequence and lid
notifier a bit.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

By our earlier reckoning, move from a snooped/llc setting to an uncached
setting, leaves the CPU cache in a consistent state irrespective of our
domain tracking - so we can forgo the warning about the lack of
invalidation. Similarly for any writes posted to the snooped CPU domain,
we know will be safely clflushed to the uncached PTEs after forcing the
domain change.

This WARN started to pop up with

commit d46f1c3f
Author:     Chris Wilson <chris@chris-wilson.co.uk>
AuthorDate: Thu Aug 8 14:41:06 2013 +0100

    drm/i915: Allow the GPU to cache stolen memory

Ville brought up a scenario where the interaction of a set_caching
ioctl call from userspace on a scanout buffer (i.e. obj->pin_display
is set) resulted in the code getting confused and not properly
flushing stale cpu cachelines. Luckily we already prevent this by
rejecting caching changes when obj->pin_count is set.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=68040Tested-by: Ncancan,feng <cancan.feng@intel.com>
[danvet: Add buglink, bisect result and explain why Ville's scenario
is already taken care of.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The conditional is usually a recoverable driver bug, and so WARNing, and
preventing the drm_mm code from doing potential damage (BUG) is
desirable.

This issue was hit and fixed twice while developing the i915 multiple
address space code. The first fix is the patch just before this, and is
hit on an not frequently occuring error path. Another was fixed during
patch iteration, so it's hard to see from the patch:

commit c6cfb325
Author: Ben Widawsky <ben@bwidawsk.net>
Date:   Fri Jul 5 14:41:06 2013 -0700

    drm/i915: Embed drm_mm_node in i915 gem obj

From the intel-gfx mailing list, we discussed this:
References: <20130705191235.GA3057@bwidawsk.net>

Cc: Dave Airlie <airlied@redhat.com>
CC: <dri-devel@lists.freedesktop.org>
Acked-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Acked-by: NDave Airlie <airlied@redhat.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Use () to make for neater alignment of the split lines, too. With this
we ditch another jump through the obj_gtt_size/offset indirection
maze.

Cc: Ben Widawsky <benjamin.widawsky@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Cleanup the map and fenceable setting during bind to make more sense,
and not check i915_is_ggtt() 2 unnecessary times

v2: Move the bools into the if block (Chris) - There are ways to tidy
this function (fence calculations for instance) even further, but they
are quite invasive, so I am punting on those unless specifically asked.

v3: Add newline between variable declaration and logic (Chris)
Recommended-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

VMAs can be created and not bound. One may think of it as lazy cleanup,
and safely gloss over the conditions which manufacture it. In either
case, when the object backing the i915 vma is destroyed, we must cleanup
the vma without stumbling into a bunch of pitfalls that assume the vma
is bound.

NOTE: I was pretty certain the above condition could only happen when we
introduced the use of VMAs being looked up at execbuf, and already
existing. Paulo has hit this though, so I must be missing something. As
I believe the patch is correct anyway, therefore I won't scratch my head
too hard.

v2: use goto destroy as a compromise (Chris)

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Use the standard inversely ordered goto label stack for everything.
Spotted while reviewing place where we might need to to call
vma_destroy but failed to do so.

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

Ideally we could use for_each_ring with the ring flags as I've done a
couple times
(http://lists.freedesktop.org/archives/intel-gfx/2013-June/029450.html).
Until Daniel merges that patch though, we can just use this.

Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We require n-1 mailboxes for proper semaphore synchronization. All
semaphore synchronization code relies on proper values in these
mailboxes. The fact that we failed to touch the vebox ring by itself
was unlikely to be an issue since the HW should be initializing the
values to 0. However the error framework for testing seqno wrap
introduced by Mika, in addition to the hangcheck via seqno, and
i915_error_first_batchbuffer() combined caused a nice explosion.

The problem is caused by seqno wrap because the wrap condition is not
properly setup. The wrap code attempts to set the sync mailboxes all
to 0, and then set the current seqno to one less than 0. In all cases,
the vebox mailbox wasn't properly being initialized. This caused a
wrap to not occur. When hangcheck kicks in with the bogus seqno
values, the rest just doesn't work. It makes me wonder if we shouldn't
consider a dumber version of hangcheck...

How we messed this up: VECS support was written before the
aforementioned other features. Upon VECS being rebased, these facts
were missed.

Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=65387
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=67198Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

It's basically the same deal as the RC6+ issues on ivy bridge
except this time with RC6 on sandy bridge. Like last time the
core of the issue is that the timings don't work 100% with our
voltage regulator. So from time to time, the kernel will print
a warning message about the GPU not getting out of RC6. In
particular, I found this fairly easy to reproduce during
suspend/resume.

Changing the threshold to 125000 instead of 50000 seems to fix
the issue. The previous patch used 150000 but as it turns out
this doesn't work everywhere. After getting such a machine, I
bisected the highest value which works, which is 125000, so here
it is.

I also measured the idle power usage before/after this patch and
didn't see a difference on a sandy bridge laptop. On haswell and
up, it makes a big difference, so we want to keep it at 50k
there. It also seems like haswell doesn't have the RC6 issues
that sandy bridge has so the 50k value is fine.
Signed-off-by: NStéphane Marchesin <marcheu@chromium.org>
Acked-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The machines that fall in this category are the SDVs that have a PCI
ID starting with 0x0C. These are very early pre-production machines
and may not fully work. Other Haswell SDVs have PCI IDs that match the
real Haswell machines and we expect them to work better.

Even though they have problems, they still mostly work so I don't see
a reason to refuse loading our driver. But I do see a reason to reject
bug reports from these machines, so the message should help the bug
triagers.

As far as I know, we don't implement some workarounds that are
specific to these machines and suspend/resume may not work on most of
them, but besides this, they may work.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=61508Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NRodrigo Vivi <rodrigo.vivi@gmail.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

After computing the stage changes for the set_config, record those in
the debug log.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Caught by "make W=1 drivers/gpu/drm/i915/".
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This is primarily for the benefit of the create2 ioctl so that the
caller can avoid the later step of rebinding the bo with new PTE bits.
After introducing WT (and possibly GFDT) cacheing for display targets,
not everything in the display is earmarked as UC, and more importantly
what is is controlled by the kernel.

Note that set_cache_level/get_cache_level for DISPLAY is not necessarily
idempotent; get_cache_level may return UC for architectures that have no
special cache domain for the display engine.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Haswell GT3e has the unique feature of supporting Write-Through cacheing
of objects within the eLLC/LLC. The purpose of this is to enable the display
plane to remain coherent whilst objects lie resident in the eLLC/LLC - so
that we, in theory, get the best of both worlds, perfect display and fast
access.

However, we still need to be careful as the CPU does not see the WT when
accessing the cache. In particular, this means that we need to flush the
cache lines after writing to an object through the CPU, and on
transitioning from a cached state to WT.

v2: Actually do the clflush on transition to WT, nagging by Ville.
v3: Flush the CPU cache after writes into WT objects.
v4: Rease onto LLC updates and report WT as "uncached" for
get_cache_level_ioctl to remain symmetric with set_cache_level_ioctl.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Although I could not reproduce this (different compiler version,
perhaps), reportedly we get:

drivers/gpu/drm/i915/i915_irq.c:1943:27: warning: ‘score’ may be used
uninitialized in this function [-Wuninitialized]

Drop the 'score' variable altogether as it's not really needed.
Reported-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The short lowercase names are bound to collide. The default warnings
don't even warn about shadowing.
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

It's been there since i8xx_irq_handler() was added in
commit c2798b19
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date:   Sun Apr 22 21:13:57 2012 +0100

    drm/i915: i8xx interrupt handler
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Some Poulsbo cards seem to incorrectly report
SDVO_CMD_STATUS_TARGET_NOT_SPECIFIED instead of
SDVO_CMD_STATUS_PENDING, which causes the display to be turned off.

This could also happen to i915.
Signed-off-by: NGuillaume Clement <gclement@baobob.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

I just noticed in our code we don't really check the assertion, and
given some of the code I am changing in this area, I feel a WARN is very
nice to have.
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
[danvet: s/&/&&/ to fix typo on the check.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Resolve the catch-22 of igt needing a stable number and patches first
needing testcases by reserving the interface number up-front.

v2: Improve the spelling a bit.

v3: More spelling fail spotted by Chris.
Requested-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Now that we skip clflushes more often, return a boolean indicating
whether the clflush was actually performed, and only if it was do the
chipset flush. (Though on most of the architectures where the clflush will
be skipped, the chipset flush is a no-op!)
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

As a corollary to reviewing the interaction between LLC and our cache
domains, the GPU PTE bits are independent of the CPU PAT bits. As such
we can set the cache level on stolen memory based on how we wish the GPU
to cache accesses to it. So we are free to set the same default cache
levels as for normal bo, i.e. enable LLC cacheing by default where
appropriate.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

As mentioned in the previous commit, reads and writes from both the CPU
and GPU go through the LLC. This gives us coherency between the CPU and
GPU irrespective of the attribute settings either device sets. We can
use to avoid having to clflush even uncached memory.

Except for the scanout.

The scanout resides within another functional block that does not use
the LLC but reads directly from main memory. So in order to maintain
coherency with the scanout, writes to uncached memory must be flushed.
In order to optimize writes elsewhere, we start tracking whether an
framebuffer is attached to an object.

v2: Use pin_display tracking rather than fb_count (to ensure we flush
cursors as well etc) and only force the clflush along explicit writes to
the scanout paths (i.e. pin_to_display_plane and pwrite into scanout).

v3: Force the flush after hitting the slowpath in pwrite, as after
dropping the lock the object's cache domain may be invalidated. (Ville)

Based on a patch by Ville Syrjälä.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The display engine has unique coherency rules such that it requires
special handling to ensure that all writes to cursors, scanouts and
sprites are clflushed. This patch introduces the infrastructure to
simply track when an object is being accessed by the display engine.

v2: Explain the is_pin_display() magic as the sources for obj->pin_count
and their individual rules is not obvious. (Ville)
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The LLC is a fun device. The cache is a distinct functional block within
the SA that arbitrates access from both the CPU and GPU cores. As such
all writes to memory land first in the LLC before further action is
taken. For example, an uncached write from either the CPU or GPU will
then proceed to memory and evict the cacheline from the LLC. This means that
a read from the LLC always returns the correct information even if the PTE
bit in the GPU differs from the PAT bit in the CPU. For the older
snooping architecture on non-LLC, the fundamental principle still holds
except that some coordination is required between the CPU and GPU to
explicitly perform the snooping (which is handled by our request
tracking).

The upshot of this is that we know that we can issue a read from either
LLC devices or snoopable memory and trust the contents of the cache -
i.e. we can forgo a clflush before a read in these circumstances.
Writing to memory from the CPU is a little more tricky as we have to
consider that the scanout does not read from the CPU cache at all, but
from main memory. So we have to currently treat all requests to write to
uncached memory as having to be flushed to main memory for coherency
with all consumers.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Due to a misplaced memset(), we never actually enabled the FBC WM on HSW.
Move the memset() to happen a bit earlier, so that it won't clobber
results->enable_fbc_wm.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Ryan noticed that on his board, HDMI was wired up to port C but not
exposed by the kernel, which had only expected DP on that port.  Fix
that up by enumerating both ports if possible.
Tested-by: N"Matsumura, Ryan" <ryan.matsumura@intel.com>
Acked-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
[danvet: Fix up the whitespace fail. Tsk.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The '!' here was not intended.  Since '!' has higher precedence than
compare, it means the check is never true.

This regression was introduced in

commit 71fff20f
Author: Ville Syrjälä <ville.syrjala@linux.intel.com>
Date:   Tue Aug 6 22:24:03 2013 +0300

    drm/i915: Kill fbc_enable from hsw_lp_wm_results
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

There is an extra semi-colon here so we just leak and never unbind
anything.

This regression has been introduced in

commit 07fe0b12
Author: Ben Widawsky <ben@bwidawsk.net>
Date:   Wed Jul 31 17:00:10 2013 -0700

    drm/i915: plumb VM into bind/unbind code

Cc: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Signed-off-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Caught by the dead code police!
Signed-off-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

And also fix a small typo in the intel_encoder_dpms() comment.
Signed-off-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Signed-off-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Did you say OCD?
Signed-off-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>