We need to use I/O port instructions to access VGA registers on
Ironlake+, and it doesn't hurt on other platforms, so switch the VGA
plane disable function over to using them.  Move it to init time as well
while we're at it, no need to repeatedly disable the VGA plane with
every mode set and DPMS event.

Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

We should disable the panel first when shutting down an eDP link.  And
when turning one on, the panel needs to be enabled before link training
or eDP I/O won't be enabled.

Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

Ironlake requires that we clear the reset panel bit during power
sequences and restore it afterwards.  Uncondtionally add code to do that
since it should be harmless on SNB+.

Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

RC6 allows the GPU to enter a lower power state when the GPU is idle.

Signed-off-by: Zou Nan hai <nanhai.zou@intel.com>
[anholt: Fixed the !renderctx error path to actually not enable RC6.]
Signed-off-by: Eric Anholt <eric@anholt.net>

If we have failed to ascertain the fixed mode for the LVDS panel, then
trust the pixel clock ranges reported for the connection when determing
valid modes. This makes intel_sdvo_mode_valid() consistent with
intel_lvds_mode_valid() which is also a no-op is there is no fixed mode
defined. (Since the mode is both validated by SDVO and LVDS, why are
checking against an LVDS fixed mode in SDVO...)

By only defining is_lvds to be true when we actually have an LVDS output
with a fixed mode, we avoid various potential NULL deferences where the
assumption is made that all LVDS outputs have a fixed mode.

References:

  Bug 29449 - [Q35] failure to read EDID/vbios for LVDS, no mode => no output
  https://bugs.freedesktop.org/show_bug.cgi?id=29449

The primary failure in this bug is not finding the EDID and determining
the correct fixed panel mode. However, this patch should fix the
secondary issue of not enabling any of the standard modes for the panel
either.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Eric Anholt <eric@anholt.net>

RC6 power state requires a logical render context in place for saving
render context.

Signed-off-by: Zou Nan hai <nanhai.zou@intel.com>
Signed-off-by: Eric Anholt <eric@anholt.net>

This is required by the spec, and without this some 3D programs will
hang after resume from RC6 we enable that.

Signed-off-by: Zou Nan hai <nanhai.zou@intel.com>
Signed-off-by: Eric Anholt <eric@anholt.net>

If our watchdog fires and we see that the GPU is idle, but that we
are still waiting on an interrupt, forcibly wake-up the waiter.

i915_do_wait_request() should not be racy, yet there are persistent
reports that 945GM hangs whilst the GPU is idle. This implies that the
hardware is not quite as coherent as the documentation claims - a write
followed by a flush is supposed to be coherent in main memory before the
flush is retired and the irq is emitted. This seems to be a sensible and
elegant guard to force the wait to timeout.

v2: Daniel Vetter pointed out that a warning would be useful to explain
why the machine appeared to stall.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Eric Anholt <eric@anholt.net>

i830 requires 32bpp cursors to be aligned to 16KB, so we have to expose
the alignment parameter to i915_gem_attach_phys_object().

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Eric Anholt <eric@anholt.net>

The i845 and i865 have a peculiarlity in that CURBASE is not the trigger
for the vsync update of the cursor registers but instead the
modification of that register is prohibited whilst the cursor is
enabled. Reorder the write sequence for CURPOS, CURCNTR and CURBASE on
i845 to i865 to match.

v2: Remove the checks for i845/i865 from within i9xx_cursor_update()

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Eric Anholt <eric@anholt.net>

The FBC is dependent upon a few details of the framebuffer so it is
required to be updated within set_base(), so remove the redundant call
from mode_set().

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Eric Anholt <eric@anholt.net>

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Eric Anholt <eric@anholt.net>

Add a new macro, wait_for, to simplify the act of waiting on a register
to change state. wait_for() takes three arguments, the condition to
inspect on every loop, the maximum amount of time to wait and whether to
yield the cpu for a length of time after each check.

v2: Upgrade failure messages to DRM_ERROR on the suggestion of
Eric Anholt. We do not expect to hit these conditions as they reflect
programming errors, so if we do we want to be notified.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Eric Anholt <eric@anholt.net>

The cleanup path for early abort failed to nullify the gem_buffer. The
likely consequence of this is zero, since a failure here should mean
aborting the module load.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Eric Anholt <eric@anholt.net>

Previously, we only remembered to update the watermarks for i9xx, and
incorrectly assumed that the crtc->enabled flag was valid at that point
in the dpms cycle.

Note that on my x201s this makes a SR bug on pipe 1 much easier to hit.
(Since before this patch when disabling pipe 0, we either didn't update
the watermarks at all, or when we did we still thought we had two pipes
enabled and so disabled SR.)

References:

  Bug 28969 - [Arrandale] Screen flickers, suspect Self-Refresh
  https://bugs.freedesktop.org/show_bug.cgi?id=28969

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Eric Anholt <eric@anholt.net>

Within i915_opregion.c there are two blocks of semantically identical
ASLE response codes defined. Only one of those matches the ACPI IGD
OpRegion Specification 0.1, use those.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Matthew Garrett <mjg59@srcf.ucam.org>
Signed-off-by: Eric Anholt <eric@anholt.net>

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Eric Anholt <eric@anholt.net>

shmfs doesn't actually implement i_ops->truncate() so we were not
immedatiately releasing the backing pages when shrinking the gfx cache
under OOM. Instead use a combination of truncate_inode_pages() and
i_ops->truncate_range() as is used by shmem_delete_inode().

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Eric Anholt <eric@anholt.net>

Writing to the DSPBASE register triggers the double-buffered update to
all the control registers, so always write it last in the update
sequence.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Eric Anholt <eric@anholt.net>

v2: Hook in DP paths to keep FULLSCREEN panel fitting on eDP.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: Eric Anholt <eric@anholt.net>

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Eric Anholt <eric@anholt.net>

Directly read the GTT mapping for the contents of the batch buffers
rather than relying on possibly stale CPU caches. Also for completeness
scan the flushing/inactive lists for the current buffers - we are
collecting error state after all.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Eric Anholt <eric@anholt.net>

In order to reduce the penalty of fallbacks under memory pressure and to
avoid a potential immediate ping-pong of evicting a mmaped buffer, we
move the object to the tail of the inactive list when a page is freshly
faulted or the object is moved into the CPU domain.

We choose not to protect the CPU objects from casual eviction,
preferring to keep the GPU active for as long as possible.

v2: Daniel Vetter found a bug where I forgot that pinned objects are
kept off the inactive list.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Eric Anholt <eric@anholt.net>

Based in a large part upon Daniel Vetter's implementation and adapted
for handling multiple rings in a single pass.

This should lead to better gtt usage and fixes the page-fault-of-doom
triggered. The fairness is provided by scanning through the GTT space
amalgamating space in rendering order. As soon as we have a contiguous
space in the GTT large enough for the new object (and its alignment),
evict any object which lies within that space. This should keep more
objects resident in the GTT.

Doing throughput testing on a PineView machine with cairo-perf-trace
indicates that there is very little difference with the new LRU scan,
perhaps a small improvement... Except oddly for the poppler trace.

Reference:

  Bug 15911 - Intermittent X crash (freeze)
  https://bugzilla.kernel.org/show_bug.cgi?id=15911

  Bug 20152 - cannot view JPG in firefox when running UXA
  https://bugs.freedesktop.org/show_bug.cgi?id=20152

  Bug 24369 - Hang when scrolling firefox page with window in front
  https://bugs.freedesktop.org/show_bug.cgi?id=24369

  Bug 28478 - Intermittent graphics lockups due to overflow/loop
  https://bugs.freedesktop.org/show_bug.cgi?id=28478

v2: Attempt to clarify the logic and order of eviction through the use
of comments and macros.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Eric Anholt <eric@anholt.net>

The eviction code is the gnarly underbelly of memory management, and is
clearer if kept separated from the normal domain management in GEM.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Eric Anholt <eric@anholt.net>

This will be used by the eviction logic to maintain fairness between the
rings.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Eric Anholt <eric@anholt.net>

This does two little changes:

- Add an alignment parameter for evict_something. It's not really great to
  whack a carefully sized hole into the gtt with the wrong alignment.
  Especially since the fallback path is a full evict.

- With the inactive scan stuff we need to evict more that one object, so
  move the unbind call into the helper function that scans for the object
  to be evicted, too.  And adjust its name.

No functional changes in this patch, just preparation.

Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Eric Anholt <eric@anholt.net>

In order to properly track bound objects, they need to exist on one of
the inactive/active lists or be pinned. As this is a requirement, do the
work inside i915_gem_bind_to_gtt() rather than dotted around the
callsites.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Eric Anholt <eric@anholt.net>

v2: Add the interrupt status and address.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Eric Anholt <eric@anholt.net>

Using dev_priv__ avoids sparse complaining about shadowed variables in
the *LP_RING() macros.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Eric Anholt <eric@anholt.net>

As the function has been reduced to a store plus increment, the body is
now smaller than the call so inline it.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Eric Anholt <eric@anholt.net>

As we check that the ringbuffer will not wrap upon emission, we do not
need to check that incrementing the tail wrapped every time. However, we
do upon advancing just in case the tail is now pointing at the very end
of the ring.

Likewise we can account for the space used during emission in begin()
and avoid decrementing it for every emit.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Eric Anholt <eric@anholt.net>

The tail is quadword aligned, so we can add two MI_NOOP as a time.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Eric Anholt <eric@anholt.net>

This debugging trace was useful for finding the fbcon regression on
i965, and it may prove useful again in future.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Eric Anholt <eric@anholt.net>

The comments have long desired that we should switch off the cursor
along with the display plane, make it so.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Eric Anholt <eric@anholt.net>

My i855GM suffers from a 80k/s interrupt storm without this.
So add 2nd gen to the list of things that don't like more than
one outstanding pageflip request.

Furthermore I've changed the busy loop into a ringbuffer wait.
Busy-loops that don't check whether the chip died are simply evil.
And performance should actually improve, because there's usually
a decent amount of rendering queued on the gpu, hopefully rendering
that MI_WAIT into a noop by the time it's executed.

The current code holds dev->struct_mutex while executing this loop,
hence stalling all other gem activity anyway.

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: stable@kernel.org
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
[anholt: resolved against conflict]
Signed-off-by: Eric Anholt <eric@anholt.net>

Add a new path for 2nd gen chips that uses the commands for i81x
chips (where public docs do exist) augmented with the plane bits
from i915. It seems to work and doesn't result in a black screen
like before.

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: stable@kernel.org
[anholt: resolved against conflict]
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Eric Anholt <eric@anholt.net>

Incorporates a similar patch by Daniel Vetter, the alteration being to
report the current busy state after retiring.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Eric Anholt <eric@anholt.net>

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Eric Anholt <eric@anholt.net>

This avoids the excess flush and requests on idle rings (and spamming
the debug log ;-)

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Eric Anholt <eric@anholt.net>