Prep-patch to improve the bpc handling in a next patch.
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Clock computations and handling are highly encoder specific, both in
the optimal clock selection and also in which clocks to use and when
sharing of clocks is possible.

So the best place to do this is somewhere in the encoders, with a
generic fallback for those encoders without special needs. To facility
this, add a pipe_config->clocks_set boolean.

This patch here is only prep work, it simply sets the computed clock
values in pipe_config->dpll, and uses that data in the hw clock
setting functions.

Haswell code isn't touched, simply because Haswell clocks work much
different and need their own infrastructure (with probably a
Haswell-specific config->ddi_clock substruct).
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Now we can ditch the checks in the Haswell disable code.

v2: add support for Haswell
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We need to be able to read out the hw state code for a bunch
of reasons:
- Correctly disabling boot-up/resume state.
- Pure paranoia.

Since not all of the pipe configuration is e.g. relevant for
fastboot (or at least we can allow some wiggle room in some
parameters, like the clocks), we need to add a strict_checking
parameter to intel_pipe_config_compare for fastboot.

For now intel_pipe_config_compare should be fully paranoid and
check everything that the hw state readout code supports. Which
for this infrastructure code is nothing.

I've gone a bit overboard with adding 3 get_pipe_config functions:
The ilk version will differ with the next patch, so it's not too
onerous.

v2: Don't check the hw config if the pipe is off, since an enabled,
but dpms off crtc will obviously have tons of difference with the hw
state.
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The only exception left is is_cpu_edp in the haswell modeset code.
We need that to assign the cpu transcoder, but we might want to
move that eventually into the encoder, too.

\o/-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We need it in the fdi m_n computation, which nicely kills almost
all ugly special cases in there.

It looks like we also need this to handle 12bpc hdmi correctly.

Eventually it might be better to switch things around and put the
target clock into adjusted_mode->clock and create a new pipe_config
parameter for the port link clock.

v2: Add a massive comment in the code to explain this mess.

v3: s/dp_target_clock/pixel_target_clock in anticipation of the hdmi
use-case.
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We need a flag to designate dp encoders and the dp link m_n parameters
in the pipe config for that. And now that the pipe bpp computations
have been moved up and stored in the pipe config, too, we can do this
without losing our sanity.

v2: Rebased on top of Takashi Iwai's fix to (again) fix the target
clock handling for eDP. Luckily the new code is sane enough and just
does the right thing!

v3: Move ->has_dp_encoder to this patch (Jesse).
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

There's a rather decent confusion going on around transcoder m_n
values. So let's clarify:
- All dp encoders need this, either on the pch transcoder if it's a
  pch port, or on the cpu transcoder/pipe if it's a cpu port.
- fdi links need to have the right m_n values for the fdi link set in
  the cpu transcoder.

To handle the pch vs transcoder stuff a bit better, extract transcoder
set_m_n helpers. To make them simpler, set intel_crtc->cpu_transcoder
als in ironlake_crtc_mode_set, so that gen5+ (where the cpu m_n
registers are all at the same offset) can use it.

Haswell modeset is decently confused about dp vs. edp vs. fdi. dp vs.
edp works exactly the same as dp (since there's no pch dp any more),
so use that as a check. And only set up the fdi m_n values if we
really have a pch encoder present (which means we have a VGA encoder).

On ilk+ we've called ironlake_set_m_n both for cpu_edp and for pch
encoders. Now that dp_set_m_n handles all dp links (thanks to the
pch encoder check), we can ditch the cpu_edp stuff from the
fdi_set_m_n function.

Since the dp_m_n values are not readily available, we need to
carefully coax the edp values out of the encoder. Hence we can't (yet)
kill this superflous complexity.

v2: Rebase on top of the ivb fdi B/C check patch - we need to properly
clear intel_crtc->fdi_lane, otherwise those checks will misfire.

v3: Rebased on top of a s/IS_HASWELL/HAS_DDI/ patch from Paulo Zanoni.

v4: Drop the addition of has_dp_encoder, it's in the wrong patch (Jesse).
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Need to make sure sprites are disabled before shutting off a pipe.
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

No constant alpha yet though, that needs a new ioctl and/or property to
get/set.

v2: use drm_plane_format_cpp (Ville)
    fix up vlv_disable_plane, remove IVB bits (Ville)
    remove error path rework (Ville)
    fix component order confusion (Ville)
    clean up platform init (Ville)
    use compute_offset_xtiled (Ville)
v3: fix up more format confusion (Ville)
    update to new page offset function (Ville)
v4: remove incorrect formats from framebuffer_init (Ville)
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Modifying the clock sources (via the DREF control on the PCH) is a slow
multi-stage process as we need to let the clocks stabilise between each
stage. If we are not actually changing the clock sources, then we can
return early.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NJani Nikula <jani.nikula@intel.com>
[danvet: Appease checkpatch by deleting a space after a ~]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Ville pointed out that my assumption that no unsupported pixel format
can get past the pipe config computation stage to the platform
update_plane callbacks is wrong. The reason is that this function
still checks the old fb->depth value instead of the new pixel_format.

While checking with all the other places that use this I've noticed
that intel_framebuffer_init already has all the platform checks we
need, so replace those checks with a WARN_ON.

Since fb->depth isn't set for YUV pixel formats and since we already
can't create an fb with an rgb layout not support on the running
platform I /think/ this patch doesn't fix any bug.

But it surely looks better!

v2: BGR formats are also only gen4+, so add the corresponding WARN_ON,
too (Ville).

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>

We've mostly switched over to the new more flexible schema, but
there's one check left in the modeset code.

Motivated by a question from Ville whether there's really no way an
unsupported pixel_format can escape into our platform update_plane
callbacks.

v2: Ville noticed that the fb->depth check is redudant when we already
check fb->pixel_format.

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>

- gen4 and earlier (save for g4x) only really have a 8bpc pipe, with
  the possibility to dither to 6bpc using the panel fitter
- g4x has hdmi, but no 12 bpc pipe ... !? Clamp hdmi accordingly.
- TV/SDVO out are the only connectors available on platforms with
  a pipe bpp != 8, add code to force the pipe to 8bpc unconditionally.

<rant>
The dither handling on gmch platforms is one giant disaster. I'm hoping
somewhat that vlv enabling will fix this up, but given that the 6bpc
handling for edp was simply added with another quick hack, I don't have
high hopes ...
</rant>

v2: Neither vlv nor g4x have 12bpc pipes. Still set pipe_bpp to 12*3,
but let the crtc code clamp things down to 10bpc on these platforms.

v3: Fix a bpc vs. bpp mixup in the gen4 and earlier pipe_bpp limiter
code.

v4: Drop the hunk in intel_hdmi.c about g4x/vlv 12bpc, it was wrong.
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

- There is no 16bpc linear color format in our hw. gen4+ has a 16 bpc
  float layout, but we don't really support it.
- 10bpc is a gen4+ feature, fix up the support for it.
- Update_plane should never see a wrong fb bpp value, BUG in the
  corresponding cases.

v2: Rebase on top of Ville's plane pixel layout changes.

v3: Actually drop the old gen4 check for 10bpc planes, spotted
by Ville Syrjälä.
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The old code only handled either 6bpc or 8bpc. Since it's easy to do,
reorganize the code to be a bit more generic so that it can also handle
10bpc and 12bpc. Note that we still start with 8bpc, so there's no
functional change.

Also, since we no don't need to compute the 6BPC flag in the mode_valid
callback, we can consolidate things a bit. That requires though that
the link bw computation is moved up in the compute_config callback.
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The procedure has now 3 steps:

1. Compute the bpp that the plane will output, this is done in
   pipe_config_set_bpp and stored into pipe_config->pipe_bpp. Also,
   this function clamps the pipe_bpp to whatever limit the EDID of any
   connected output specifies.
2. Adjust the pipe_bpp in the encoder and crtc functions, according to
   whatever constraints there are.
3. Decide whether to use dither by comparing the stored plane bpp with
   computed pipe_bpp.

There are a few slight functional changes in this patch:
- LVDS connector are now also going through the EDID clamping. But in
  a 2nd change we now unconditionally force the lvds bpc value - this
  shouldn't matter in reality when the panel setup is consistent, but
  better safe than sorry.
- HDMI now forces the pipe_bpp to the selected value - I think that's
  what we actually want, since otherwise at least the pixelclock
  computations are wrong (I'm not sure whether the port would accept
  e.g. 10 bpc when in 12bpc mode). Contrary to the old code, we pick
  the next higher bpc value, since otherwise there's no way to make
  use of the 12 bpc mode (since the next patch will remove the 12bpc
  plane format, it doesn't exist).

Both of these changes are due to the removal of the

	pipe_bpp = min(display_bpp, plane_bpp);

statement.

Another slight change is the reworking of the dp bpc code:
- For the mode_valid callback it's sufficient to only check whether
  the mode would fit at the lowest bpc.
- The bandwidth computation code is a bit restructured: It now walks
  all available bpp values in an outer loop and the codeblock that
  computes derived values (once a good configuration is found) has been
  moved out of the for loop maze. This is prep work to allow us to
  successively fall back on bpc values, and also correctly support bpc
  values != 8 or 6.

v2: Rebased on top of Paulo Zanoni's little refactoring to use more
drm dp helper functions.

v3: Rebased on top of Jani's eDP bpp fix and Ville's limited color
range work.

v4: Remove the INTEL_MODE_DP_FORCE_6BPC #define, no longer needed.

v5: Remove intel_crtc->bpp, too, and fix up the 12bpc check in the
hdmi code. Also fixup the bpp check in intel_dp.c, it'll get reworked
in a later patch though again.

v6: Fix spelling in a comment.

v7: Debug output improvements for the bpp computation.

v8: Fixup 6bpc lvds check - dual-link and 8bpc mode are different
things!

v9: Reinstate the fix to properly ignore the firmware edp bpp ... this
was lost in a rebase.

v10: Both g4x and vlv lack 12bpc pipes, so don't enforce that we have
that. Still unsure whether this is the way to go, but at least 6bpc
for a 8bpc hdmi output seems to work.

v11: And g4x/vlv also lack 12bpc hdmi support, so only support high
depth on DP. Adjust the code.

v12: Rebased.

v13: Split out the introduction of pipe_config->dither|pipe_bpp, as
requested from Jesse Barnes.

v14: Split out the special 6BPC handling for DP, as requested by Jesse
Barnes.
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We want to compute this earlier. To avoid a big complicated patch,
this patch here just does the big search&replace and still calls the
old functions at the same places.
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Now that we have a useful struct for this, let's use it. Some neat
pointer-chasing required, but it's all there already.

v2: Rebased on top of the added Haswell limited color range support.
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This is used way too often in the enable/disable paths. And will
be even more useful in the future.

Note that correct semantics of this change highly depend upon
correct updating of intel_crtc->config: Like with all other
modeset state, we need to call ->disable with the old config,
but ->mode_set and ->enable with the new config.

v2: Do not yet use the flag in the ->disable callbacks - atm we don't
yet have support for the information stored in the pipe_config in the
hw state readout code, so this will be wrong at boot-up/resume.

v3: Rebased on top of the hdmi/dp ddi encoder merging.

v4: Fixup stupid rebase error which lead to a NULL vfunc deref.

v5: On haswell the VGA port is on the PCH!

v6: s/IS_HASWELL/HAS_DDI/, spotted by Paulo Zanoni. Also add a missing
parameter name in a function declaration.

v7: Don't forget to git add ...
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Used by SDVO (and hopefully, eventually HDMI, if we ever get around
to fixing up the low dotclock CEA modes ...).

This required adding a new encoder->mode_set callback to be able to
pass around the intel_crtc_config.
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Only used by the lvds encoder. Note that we shouldn't do the same
simple conversion with the FORCE_6BPC flag, since that's much better
handled by moving all the pipe_bpc computation around.

This requires that we pass the pipe config around to encoders, so
that they can set special attributes and set constraints. To do so
introduce a new ->compute_config encoder callback, which is called in
stead of the drm crtc helper's ->mode_fixup.

To avoid massive churn all over the codebase we don't want to convert
all existing ->mode_fixup functions. Instead I've opted to convert
them on an as-needed basis (mostly to cut down on rebase conflicts and
to have more freedom to experiment around while developing the
patches).
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

To make decent modeset state checking possible (e.g. for the check
mode with atomic modesetting) we want to have the full pipe
configuration and state checks done before we touch the hw.

To ensure that all the little bits&pieces that are now moved to the
pipe_config handle this correctly, move its computation to the right
spot now, before we touch the hw in the disable_pipes step.
Reviewed-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Currently only containing the requested and the adjusted mode. And
only crtc callbacks are converted somewhat to it, encoders will be
done on a as-needed basis (simply too much churn in one patch
otherwise).

Future patches will add tons more useful stuff to this struct,
starting with the very simple.

v2: Store the pipe_config in the intel_crtc, so that the ->mode-set,
->enable and also ->disable have easy access to it.

v3: Store the pipe config in the right crtc ...

v4: Rebased.

v5: Fixup an OOPS when trying to kfree an ERR_PTR.

v6: Used drm_moode_copy and some other small cleanups as suggested
by Ville Syrjälä.

v7: drm_mode_copy preserves the mode id of the destination, so no need
to clear it again (Ville).

v8: Break a long line spotted by Paulo.
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

From the w/a database:

'To prevent false VT-d type 6 error:

  The primary display plane must be 256KiB aligned, and require an extra
  128 PTEs of padding afterward;

  The sprites planes must be 128KiB aligned, and require an extra 64 PTEs
  of padding afterward;

  The cursors must be 64KiB aligned, and require an extra 2 PTEs of
  padding afterward.'

As we use the same function to pin the primary and sprite planes, we can
simply use the more strict requirements for scanouts for both.

Instead of using explicit padding PTEs following the scanout objects, we
should be able to use the scratch page that is always mapped into the
unused PTEs to avoid the VT-d error.

References: https://bugs.freedesktop.org/show_bug.cgi?id=59626
References: https://bugs.freedesktop.org/show_bug.cgi?id=59627
References: https://bugs.freedesktop.org/show_bug.cgi?id=59631Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
[danvet: Apply s/vtd_wa/vtd_scanout_wa/ bikeshed since Damien likes
it, too.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Needed for VT switchless resume.

v2: cursor state is now handled correctly in crtc_enable (Daniel)
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: NRodrigo Vivi <rodrigo.vivi@gmail.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This reverts commit cc464b2a.

The reason is that Takashi Iwai reported a regression bisected to this
commit:

http://www.mail-archive.com/intel-gfx@lists.freedesktop.org/msg18788.html

His machine has eDP on port D (usual desktop all-in-on setup), which
intel_dp.c identifies as an eDP panel, but the hsw ddi code
mishandles.

Closer inspection of the code reveals that haswell_crtc_mode_set also
checks intel_encoder_is_pch_edp when setting is_cpu_edp. On haswell
that doesn't make much sense (since there's no edp on the pch), but
what this function _really_ checks is whether that edp connector is on
port A or port D. It's just that on ilk-ivb port D was on the pch ...

So that explains why this seemingly innocent change killed eDP on port
D. Furthermore it looks like everything else accidentally works, since
we've never enabled eDP on port D support for hsw intentionally (e.g.
we still register the HDMI output for port D in that case).

But in retrospective I also don't like that this leaks highly platform
specific details into common code, and the reason is that the drm
vblank layer sucks. So instead I think we should:
- move the cpu_transcoder into the dynamic pipe_config tracking (once
  that's merged).
- fix up the drm vblank layer to finally deal with kms crtc objects
  instead of int pipes.

v2: Pimp commit message with the better diagnosis as discussed with
Paulo on irc.

Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Cc: Takashi Iwai <tiwai@suse.de>
Reviewed-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

So don't read it when capturing the error state. This solves some
"unclaimed register" messages on Haswell when we hang the GPU.
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The first version of commit "drm/i915: there's no DSPADDR register on
Haswell" added 2 "!IS_HASWELL" checks. When reviewing the patch, Ben
suggested to make these checks more future-proof, so when Daniel
applied the patch he fixed the first check but not the second. This
commit makes the second check also "future-proof".
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We are really talking about the transcoder function here and the disable
version uses trancoder in its name already, so let's try to be
consistent.
Signed-off-by: NDamien Lespiau <damien.lespiau@intel.com>
Reviewed-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

In the case where the hardware has been wrongly programmed and the EDP
TRANS_DDI_FUNC_CTL register has a bogus value in its EDP Input field, we
were using the pipe variable uninitialized.

In this case, shutdown the transcoder. It will be programmed correctly
the next time we try to enabled eDP.

Note from Paulo's review: Wrong modeset sequence can easily lead to
frozen machines hence the disable_ddi call might be risky. But since
things are awry already, doesn't matter too much.
Signed-off-by: NDamien Lespiau <damien.lespiau@intel.com>
Reviewed-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
[danvet: Add note about Paulo's caution about potential hangs.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This comment looks like some historical leftover. Get rid of it.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Requested by Daniel.

v2: Fix incorrect num_pipe settings. (Chris)

Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Port C is for eDP.  Port B is shared between HDMI and DP.
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Planes are fixed to pipes in VLV.
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

So don't read it when we hang the GPU. This solves "unclaimed
register" messages.
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NBen Widawsky <ben@bwidawsk.net>
[danvet: Future-proof by adding a gen >= 7 check in addition to the
!IS_HSW check from Paulo's original patch, suggested by Ben.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

So don't read it when capturing the error state. This solves some
"unclaimed register" messages on Haswell when we hang the GPU.
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This solves some "unclaimed register" messages when there's a GPU hang
on Haswell.
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NBen Widawsky <ben@bwidawsk.net>
[danvet: Add missing IS_VLV check as spotted by Ville Syrjälä.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Some HDMI registers can be used for SDVO, so saying "HDMIB" should be
the same as saying "SDVOB" for a given HW generation. This was not
true and led to confusions and even a regression.

Previously we had:
  - SDVO{B,C} defined as the Gen3+ registers
  - HDMI{B,C,D} and PCH_SDVOB defined as the PCH registers

But now:
  - SDVO{B,C} became GEN3_SDVO{B,C} on SDVO code
  - SDVO{B,C} became GEN4_HDMI{B,C} on HDMI code
  - HDMI{B,C,D} became PCH_HDMI{B,C,D}
  - PCH_SDVOB is still the same thing

v2: Rebase (v1 was sent in May 2012).
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>