Hugh Dickins found that characters in xterm were going missing and oft
delayed. Being the curious type, he managed to associate this with the
new high-precision vblank patches; disabling these he found, restored
the orderliness of his characters.

The oddness begins when one realised that Hugh was not using vblanks at
all on his system (fvwm and some xterms). Instead, all he had to go on
were warning of a pipe underrun, curiously enough at around 60Hz. He
poked and found that in addition to the underrun warning, the hardware
was flagging the start of a new frame, a vblank, which in turn was
kicking off the pending vblank processing code.

There is little we can do for the underruns on Hugh's machine, a
Crestline [965GM], which must have its FIFO watermarks set to 8.
However, we do not need to process the vblank if we know that they are
disabled...
Reported-by: NHugh Dickins <hughd@google.com>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>

error_bo and pinned_bo could be used uninitialised if there were no
active buffers.

Caught by kmemcheck.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>

If the driver calls into the kernel to wait for a breadcrumb to pass,
but hasn't enabled interrupts, fallback to polling the breadcrumb value.
Reported-by: NChris Clayton <chris2553@googlemail.com>
Tested-by: NChris Clayton <chris2553@googlemail.com>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>

Reported-by: NChris Clayton <chris2553@googlemail.com>
Tested-by: NChris Clayton <chris2553@googlemail.com>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>

Hangcheck and error recovery is only used by GEM.
Reported-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>

Whilst we had no older batches on the active list, everything was fine.
However, if the GPU is free running and the requests are only being
reaped by the periodic retirer, than the current seqno may not be at the
start of the list. In this case we need to select the first batch after
the last seqno written by the gpu and not inclusive of the seqno.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>

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

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

FDI and the transcoders can fail for various reasons, so detect those
conditions and report on them.
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>

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

Otherwise we may consume 20% of the CPU just handling IRQs whilst
rendering. Ouch.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>

Add an interrupt handler for switching graphics frequencies and handling
PM interrupts.  This should allow for increased performance when busy
and lower power consumption when idle.
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>

v2: Change IS_IRONLAKE to IS_GEN5 to adapt to 2.6.37

This patch adds new functions for use by the drm core:

.get_vblank_timestamp() provides a precise timestamp
for the end of the most recent (or current) vblank
interval of a given crtc, as needed for the DRI2
implementation of the OML_sync_control extension.
It is a thin wrapper around the drm function
drm_calc_vbltimestamp_from_scanoutpos() which does
almost all the work.

.get_scanout_position() provides the current horizontal
and vertical video scanout position and "in vblank"
status of a given crtc, as needed by the drm for use by
drm_calc_vbltimestamp_from_scanoutpos().

The patch modifies the pageflip completion routine
to use these precise vblank timestamps as the timestamps
for pageflip completion events.

This code has been only tested on a HP-Mini Netbook with
Atom processor and Intel 945GME gpu. The codepath for
(IS_G4X(dev) || IS_GEN5(dev) || IS_GEN6(dev)) gpu's
has not been tested so far due to lack of hardware.
Signed-off-by: NMario Kleiner <mario.kleiner@tuebingen.mpg.de>
Acked-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>

Restore PIPE_CONTROL once again just for Ironlake, as it appears that
MI_USER_INTERRUPT does not have the same coherency guarantees, that is
on Ironlake the interrupt following a GPU write is not guaranteed to
arrive after the write is coherent from the CPU, as it does on the
other generations.
Reported-by: NZhenyu Wang <zhenyuw@linux.intel.com>
Reported-by: NShuang He <shuang.he@intel.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=32402Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>

In order to enforce the correct memory barriers for irq get/put, we need
to perform the actual counting using atomic operations.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>

The workaround is hideous and we are using the STORE_DWORD on all other
generations on all other rings, so use for the gen5 render ring as
well.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>

The bulk of the change is to convert the growing list of rings into an
array so that the relationship between the rings and the semaphore sync
registers can be easily computed.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>

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

Having seen the effects of erroneous fencing on the batchbuffer, a
useful sanity check is to record the fence registers at the time of an
error.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>

A glorified s/obj_priv/obj/ with a net reduction of over a 100 lines and
many characters!
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>

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

When trying to diagnose mysterious errors on resume, capture the
display register contents as well.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>

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: NChris Wilson <chris@chris-wilson.co.uk>

... and so hide the flushes from tracing.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>

We only ever used the PRB0, neglecting the secondary ring buffers, and
now with the advent of multiple engines with separate ring buffers we
need to excise the anachronisms from our code (and be explicit about
which ring we mean where). This is doubly important in light of the
FORCEWAKE required to read ring buffer registers on SandyBridge.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>

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

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

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

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

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

Currently, we believe the GPU is idle if just the RENDER ring is idle.
This is obviously wrong if we only using either the BLT or the BSD
rings and so masking genuine hangs.
Signed-off-by: NChris 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: NChris 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: NChris Wilson <chris@chris-wilson.co.uk>

Keep the current interface but ignore the KM_type and use a stack based
approach.

The advantage is that we get rid of crappy code like:

	#define __KM_PTE			\
		(in_nmi() ? KM_NMI_PTE : 	\
		 in_irq() ? KM_IRQ_PTE :	\
		 KM_PTE0)

and in general can stop worrying about what context we're in and what kmap
slots might be appropriate for that.

The downside is that FRV kmap_atomic() gets more expensive.

For now we use a CPP trick suggested by Andrew:

  #define kmap_atomic(page, args...) __kmap_atomic(page)

to avoid having to touch all kmap_atomic() users in a single patch.

[ not compiled on:
  - mn10300: the arch doesn't actually build with highmem to begin with ]

[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: fix up drivers/gpu/drm/i915/intel_overlay.c]
Acked-by: NRik van Riel <riel@redhat.com>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: NChris Metcalf <cmetcalf@tilera.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: David Miller <davem@davemloft.net>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Dave Airlie <airlied@linux.ie>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

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: NChris 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: NChris Wilson <chris@chris-wilson.co.uk>

"userpace" -> "userspace"
Signed-off-by: NAndrea Gelmini <andrea.gelmini@gelma.net>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>

On Sandybridge, the bit definition for hotplug on SDE has changed, so
update the code to new definition.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=30378
Cc: stable@kernel.org
Signed-off-by: NYuanhan Liu <yuanhan.liu@intel.com>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>

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