The render P-state handling code requires reading from a GT register.
This means that FORCEWAKE must be written to, a resource which is shared
and should be protected by struct_mutex. Hence we can not manipulate
that register from within the interrupt handling and so must delegate
the task to a workqueue.
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NKeith Packard <keithp@keithp.com>

This reverts commit 951f3512

    drm/i915: Do not handle backlight combination mode specially

since this commit introduced other regressions due to untouched LBPC
register, e.g. the backlight dimmed after resume.

In addition to the revert, this patch includes a fix for the original
issue (weird backlight levels) by removing the wrong bit shift for
computing the current backlight level.
Also, including typo fixes (lpbc -> lbpc).

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=34524Acked-by: NIndan Zupancic <indan@nul.nu>
Reviewed-by: NKeith Packard <keithp@keithp.com>
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Cc: <stable@kernel.org>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Whilst the GT is powered down (rc6), writes to MMADDR are placed in a
FIFO by the System Agent. This is a limited resource, only 64 entries, of
which 20 are reserved for Display and PCH writes, and so we must take
care not to queue up too many writes. To avoid this, there is counter
which we can poll to ensure there are sufficient free entries in the
fifo.

"Issuing a write to a full FIFO is not supported; at worst it could
result in corruption or a system hang."
Reported-and-Tested-by: NMatt Turner <mattst88@gmail.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=34056Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>

I stumbled over this magic bit in the gen3 INSTPM:

Bit11 Interrupt-Based AGPBUSY# Enable:

‘0’ = Pending GMCH interrupts will not cause AGPBUSY# assertion.
‘1’ = Pending GMCH interrupts will cause AGPBUSY# assertion and hence
      can cause the CPU to exit C3.  There is no suppression of cacheable
      writes.

Note that in either case in C3 the interrupts are not lost. They will be
forwarded to the ICH when the GMCH is out of C3.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Tested-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Cc: stable@kernel.org

In order to prevent "crushed blacks" on TVs, the range of the RGB output
may be limited to 16-235. This used to be available through Xorg under
the "Broadcast RGB" option, so reintroduce support for KMS.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=34543Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>

The current code does not follow Intel documentation: It misses some things
and does other, undocumented things. This causes wrong backlight values in
certain conditions. Instead of adding tricky code handling badly documented
and rare corner cases, don't handle combination mode specially at all. This
way PCI_LBPC is never touched and weird things shouldn't happen.

If combination mode is enabled, then the only downside is that changing the
brightness has a greater granularity (the LBPC value), but LBPC is at most
254 and the maximum is in the thousands, so this is no real functional loss.

A potential problem with not handling combined mode is that a brightness of
max * PCI_LBPC is not bright enough. However, this is very unlikely because
from the documentation LBPC seems to act as a scaling factor and doesn't look
like it's supposed to be changed after boot. The value at boot should always
result in a bright enough screen.

IMPORTANT: However, although usually the above is true, it may not be when
people ran an older (2.6.37) kernel which messed up the LBPC register, and
they are unlucky enough to have a BIOS that saves and restores the LBPC value.
Then a good kernel may seem to not work: Max brightness isn't bright enough.
If this happens people should boot back into the old kernel, set brightness
to the maximum, and then reboot. After that everything should be fine.

For more information see the below links. This fixes bugs:

  http://bugzilla.kernel.org/show_bug.cgi?id=23472
  http://bugzilla.kernel.org/show_bug.cgi?id=25072Signed-off-by: NIndan Zupancic <indan@nul.nu>
Tested-by: NAlex Riesen <raa.lkml@gmail.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Disable any PCH ports associated with a pipe when disabling it.  This
should prevent transcoder disable failures due to ports still being on.
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
[ickle: introduce *_PIPE_ENABLED() macro]
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>

We had some conversions over to the _PIPE macros, but didn't get
everything.  So hide the per-pipe regs with an _ (still used in a few
places for legacy) and add a few _PIPE based macros, then make sure
everyone uses them.

[update: remove usage of non-existent no-op macro]
[update 2: keep modesetting suspend/resume code, update to new reg names]
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
[ickle: stylistic cleanups for checkpatch and taste]
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>

The specs say to do so.
Signed-off-by: NEric Anholt <eric@anholt.net>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>

Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: stable@kernel.org

The i915 driver normally assumes the video bios has configured several
of the LVDS panel registers, and it just inherits the values. If the
vbios has not run, several of these will need to be setup. So we need to
check that the LVDS sync polarity is correctly configured per any
available modelines (e.g. EDID) and adjust if not, issuing a warning as
we do.
Signed-off-by: NMark Hayter <mdhayter@chromium.org>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>

These make us increase our frequency much more readily, and decrease
them only after significant idle time, resulting in a 20% performance
increase for nexuiz.
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>

We need to unlock the phase sync pointer enable bit before we can
actually enable the phase sync pointer workaround on Ironlake.
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>

With assertions to check transcoder and reference clock state.
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>

Add plane enable/disable functions to prevent duplicated code and allow
us to easily check for plane enable/disable requirements (such as pipe
enable, plane status, pll status etc).
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>

Without this change, blits to the front buffer won't invalidate FBC
state, causing us to scan out stale data.  Make sure we update these
bits on every FBC enable, since they may get clobbered if we shut off
the display.

References: https://bugzilla.kernel.org/show_bug.cgi?id=26932Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>

Add a couple of missing workaround bits for ILK & SNB.  These disable
clock gating on a couple of units that would otherwise prevent FBC from
working.
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
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>

Re-enable rc6 support on Ironlake for power savings.  Adds a debugfs
file to check current RC state, adds a missing workaround for Ironlake
MI_SET_CONTEXT instructions, and renames MCHBAR_RENDER_STANDBY to
RSTDBYCTL to match the docs.

Keep RC6 and the power context disabled on pre-ILK.  It only seems to
hang and doesn't save any power.
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
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>

This patch actually makes the watermark code even uglier (if that's
possible), but has the advantage of sharing code between SNB and ILK at
least.  Longer term we should refactor the watermark stuff into its own
file and clean it up now that we know how it's supposed to work.

Supporting WM2 on my Vaio reduced power consumption by around 0.5W, so
this patch is definitely worthwhile (though it also needs lots of test
coverage).
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
[ickle: pass the watermark structs arounds]
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>

In some configuration, the PCU may allow us to overclock the GPU.
Check for this case and adjust the max frequency as appropriate.  Also
initialize the min/max frequencies to default values as indicated by
hardware.
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>

Some voltage swing/pre-emphasis level use the same value on eDP
Sandybridge, like 400mv_0db and 600mv_0db are with the same value
of (0x0 << 22). So, fix them, and point out the value if it isn't
a supported voltage swing/pre-emphasis level.
Signed-off-by: NYuanhan Liu <yuanhan.liu@linux.intel.com>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: stable@kernel.org

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

It's required by the specs, but we don't know why.  Let's not find out
why.
Signed-off-by: NEric Anholt <eric@anholt.net>
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>

Add frame buffer compression on Sandybridge. The method is similar to
Ironlake, except that two new registers of type GTTMMADR must be written
with the right fence info.
Signed-off-by: NYuanhan Liu <yuanhan.liu@linux.intel.com>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>

Add the support of memory self-refresh on Sandybridge, which is now
support 3 levels of watermarks and the source of the latency values
for watermarks has changed.

On Sandybridge, the LP0 WM value is not hardcoded any more. All the
latency value is now should be extracted from MCHBAR SSKPD register.
And the MCHBAR base address is changed, too.

For the WM values, if any calculated watermark values is larger than
the maximum value that can be programmed into the associated watermark
register, that watermark must be disabled.
Signed-off-by: NYuanhan Liu <yuanhan.liu@linux.intel.com>
[ickle: remove duplicate compute routines and fixup for checkpatch]
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>

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

Once we have read the value out of the GT power well, we need to remove
the FORCE WAKE bit to allow the system to auto-power down.
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>

Magic numbers from the specs. This is supposed to allow the PLL some
variance to improve jitter performance and VCO headroom across
manufacturing and environmental variations.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>

The pipe is always set to 8BPC, but here we were leaving whatever
previous bits were set by the BIOS in place.
Signed-off-by: NEric Anholt <eric@anholt.net>
Tested-by: NKeith Packard <keithp@keithp.com>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: stable@kernel.org

Not employed just yet...
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>

This has proven sufficient to recover from a hang of the GPU using the
gem_bad_blit test while at the KMS console then starting X.  When
attempting the same during an X session, the timer doesn't appear to
trigger.
Signed-off-by: NEric Anholt <eric@anholt.net>
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>

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>

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: NZou Nan hai <nanhai.zou@intel.com>
[ickle: added a udelay which seemed to do the trick on my SNB]
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>

Not known to fix any current bugs.
Signed-off-by: NEric Anholt <eric@anholt.net>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>