The pinned buffers are useful for diagnosing errors in setting up state
for the chipset, which may not necessarily be 'active' at the time of
the error, e.g. the cursor buffer object.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

An old and oft reported bug, is that of the GPU hanging on a
MI_WAIT_FOR_EVENT following a mode switch. The cause is that the GPU is
waiting on a scanline counter on an inactive pipe, and so waits for a
very long time until eventually the user reboots his machine.

We can prevent this either by moving the WAIT into the kernel and
thereby incurring considerable cost on every swapbuffers, or by waiting
for the GPU to retire the last batch that accesses the framebuffer
before installing a new one. As mode switches are much rarer than swap
buffers, this looks like an easy choice.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=28964
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=29252Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: stable@kernel.org

Before reading ring register, set FORCE_WAKE bit to prevent GT core
power down to low power state, otherwise we may read stale values.
Signed-off-by: Zou Nan hai <nanhai.zou@intel.com>
[ickle: added a udelay which seemed to do the trick on my SNB]
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

... as it has been replaced by per-ring waiters.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

As we use POSTING_READ to flush the write to the register before
proceeding, we do not care what the return value is and similar we do
not care for the read to be recorded whilst tracing register
read/writes.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

This will be used later to hide the frequently written registers
from debug traces in order to increase the signal-to-noise.
Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

Add two tracepoints at I915_WRITE/READ for tracing down all the
register write and read.
Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

a00b10c3 "Only enforce fence limits inside the GTT" also
added a fenceable/mappable disdinction when binding/pinning buffers.
This only complicates the code with no pratical gain:

- In execbuffer this matters on for g33/pineview, as this is the only
  chip that needs fences and has an unmappable gtt area. But fences
  are only possible in the mappable part of the gtt, so need_fence
  implies need_mappable. And need_mappable is only set independantly
  with relocations which implies (for sane userspace) that the buffer
  is untiled.

- The overlay code is only really used on i8xx, which doesn't have
  unmappable gtt. And it doesn't support tiled buffers, currently.

- For all other buffers it's a bug to pass in a tiled bo.

In short, this disdinction doesn't have any practical gain.

I've also reverted mapping the overlay and context pages as possibly
unmappable. It's not worth being overtly clever here, all the big
gains from unmappable are for execbuf bos.

Also add a comment for a clever optimization that confused me
while reading the original patch by Chris Wilson.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

Signed-off-by: Zhenyu Wang <zhenyu.z.wang@intel.com>
Cc: stable@kernel.org
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

We can use mmiotrace instead of our own debug printks.

This reverts commit be282fd4.

Conflicts:

	drivers/gpu/drm/i915/i915_drv.h

... and into a local structure scoped for the single function in which
it is used.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

Take two passes to evict everything whilst searching for sufficient free
space to bind the batchbuffer. After searching for sufficient free space
using LRU eviction, evict everything that is purgeable and try again.
Only then if there is insufficient free space (or the GTT is too badly
fragmented) evict everything from the aperture and try one last time.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

So long as we adhere to the fence registers rules for alignment and no
overlaps (including with unfenced accesses to linear memory) and account
for the tiled access in our size allocation, we do not have to allocate
the full fenced region for the object. This allows us to fight the bloat
tiling imposed on pre-i965 chipsets and frees up RAM for real use. [Inside
the GTT we still suffer the additional alignment constraints, so it doesn't
magic allow us to render larger scenes without stalls -- we need the
expanded GTT and fence pipelining to overcome those...]
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

By using read_cache_page() for individual pages during pwrite/pread we
can eliminate an unnecessary large allocation (and immediate free) of
obj->pages. Also this eliminates any potential nesting of get/put pages,
simplifying the code and preparing the path for greater things.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

Since we rarely use the mmap_offset and it is easily computable from the
obj->map_list.hash, remove it.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

Eliminate the racy device unload by embedding a shrinker into each
device. Smaller, simpler code.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

This holds error state from the main graphics arbiter mainly involving
the DMA engine and address translation.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

More precisely: For those that _need_ to be mappable. Also add two
BUG_ONs in fault and pin to check the consistency of the mappable
flag.

Changes in v2:
- Add tracking of gtt mappable space (to notice mappable/unmappable
  balancing issues).
- Improve the mappable working set tracking by tracking fault and pin
  separately.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

At least the part that's currently enabled by the BIOS.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

Like before add a parameter mappable (also to gem_object_pin) and
set it depending upon the context. Only bos that are brought into
the gtt due to an execbuffer call can be put into the unmappable
part of the gtt, everything else (especially pinned objects) need
to be put into the mappable part of the gtt.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

Add a mappable parameter to i915_gem_evict_something to distinguish
the two cases (non-restricted vs. mappable gtt allocations). No
functional changes because the mappable limit is set to the end of
the gtt currently.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

Preparing the ringbuffer for adding new commands can fail (a timeout
whilst waiting for the GPU to catch up and free some space). So check
for any potential error before overwriting HEAD with new commands, and
propagate that error back to the user where possible.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

The ringbuffer keeps a pointer to the parent device, so we can use that
instead of passing around the pointer on the stack.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

... to prevent flush processing of an idle (or even absent) ring.

This fixes a regression during suspend from 87acb0a5.
Reported-and-tested-by: Alexey Fisher <bug-track@fisher-privat.net>
Tested-by: Peter Clifton <pcjc2@cam.ac.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

So remove the redundant bit in the capabilities block and
s/IS_IRONLAKE/IS_GEN5/.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

Based on an original patch by Zhenyu Wang, this initializes the BLT ring for
SandyBridge and enables support for user execbuffers.

Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

To handle retirements, we need per-ring tracking of active objects.
To handle evictions, we need global tracking of active objects.

As we enable more rings, rebuilding the global list from the individual
per-ring lists quickly grows tiresome and overly complicated. Tracking the
active objects in two lists is the lesser of two evils.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

Cache the first 4 bytes of DPCD data in the eDP case.  It's unlikely to
change and can save us some trouble at link training time.
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

We need to use some of these values in eDP configurations, so be sure to
fetch them and store them in the i915 private structure.
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

The _DSM method on the integrated graphics device can tell us which
connectors are muxable, so add support for making the call and parsing
out the connector info.
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
[ickle: fix compiler warnings for using uninitialized 'result' and
downgrade error message for non-switchable devices]
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

The issue is that we may become stuck executing a long running shader
and continually attempt to reset the GPU. (Or maybe we tickle some bug
and need to break the vicious cycle.) So if we are detect a second hang
within 5 seconds, give up trying to programme the GPU and report it
wedged.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

When the GPU is reset, the fence registers are invalidated, so release
the objects and clear them out.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

Only drm/i915 does the bookkeeping that makes the information useful,
and the information maintained is driver specific, so move it out of the
core and into its single user.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Dave Airlie <airlied@redhat.com>

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

... and check more regularly.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>