1. 06 9月, 2012 13 次提交
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      drm/i915: introduce struct intel_set_config · d9e55608
      Daniel Vetter 提交于
      intel_crtc_set_config is an unwidly beast and is in serious need of
      some function extraction. To facilitate that, introduce a struct to
      keep track of all the state involved. Atm it doesn't do much more than
      keep track of all the allocated memory.
      
      v2: Apply some bikeshed to intel_set_config_free, as suggested by
      Jesse Barnes.
      Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
      Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
      d9e55608
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      drm/i915: rip out intel_dp->dpms_mode · 24e804ba
      Daniel Vetter 提交于
      We now track the connector state in encoder->connectors_active, and
      because the DP output can't be cloned, that is sufficient to track the
      link state. Hence use this instead of adding yet another modeset state
      variable with dubious semantics at driver load and resume time.
      
      Also, connectors_active should only ever be set when the encoder is
      linked to a crtc, hence convert that crtc test into a WARN.
      
      v2: Rebase on top of struct intel_dp moving.
      
      v3: The rebase accidentally killed the newly-introduced intel_dp->port
      Noticed by Paulo Zanoni.
      Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
      Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
      24e804ba
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      drm/i915: rip out intel_crtc->dpms_mode · 84bb65bd
      Daniel Vetter 提交于
      Afaict this has been used for two things:
      - To prevent the crtc enable code from being run twice. We have now
        intel_crtc->active to track this in a more precise way.
      - To ensure the code copes correctly with the unknown hw state after
        boot and resume. Thanks to the hw state readout and sanitize code we
        have now a better way to handle this.
      
      The only thing it still does is complicate our modeset state space.
      
      Having outlived its usefullness, let it just die.
      Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
      Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
      84bb65bd
    • D
      drm/i915: check connector hw/sw state · 0a91ca29
      Daniel Vetter 提交于
      Atm we can only check the connector state after a dpms call - while
      doing modeset with the copy&pasted crtc helper code things are too
      ill-defined for proper checking. But the idea is very much to call
      this check from the modeset code, too.
      
      v2: Fix dpms check and don't presume that if the hw isn't on that it
      must not be linked up with an encoder (it could simply be switched off
      with the dpms state).
      Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
      Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
      0a91ca29
    • D
      85234cdc
    • D
      drm/i915: Add interfaces to read out encoder/connector hw state · f0947c37
      Daniel Vetter 提交于
      It is all glorious if we try really hard to only enable/disable an
      entire display pipe to ensure that everyting happens in the right
      order. But if we don't know the output configuration when the driver
      takes over, this will all be for vain because we'll make the hw angry
      right on the first modeset - we don't know what outputs/ports are
      enabled and hence have to disable everything in a rather ad-hoc way.
      
      Hence we need to be able to read out the current hw state, so that we
      can properly tear down the current hw state on the first modeset.
      Obviously this is also a nice preparation for the fastboot work, where
      we try to avoid the modeset on driver load if it matches what the hw
      is currently using.
      
      Furthermore we'll be using these functions to cross-check the actual
      hw state with what we think it should be, to ensure that the modeset
      state machine actually works as advertised.
      
      This patch only contains the interface definitions and a little helper
      for the simple case where we have a 1:1 encoder to connector mapping.
      Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
      Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
      f0947c37
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      drm/i915: WARN when trying to enabled an unused crtc · 08a48469
      Daniel Vetter 提交于
      This is the first tiny step towards cross-checking the entire modeset
      state machine with WARNs. A crtc can only be enabled when it's
      actually in use, i.e. crtc->active imlies crtc->enabled.
      
      Unfortunately we can't (yet) check this when disabling the crtc,
      because the crtc helpers are a bit slopy with updating state and
      unconditionally update crtc->enabled before changing the hw state.
      
      Fixing that requires quite some more work.
      Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
      Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
      08a48469
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      drm/i915: rip out encoder->prepare/commit · c9deac97
      Daniel Vetter 提交于
      With the new infrastructure we're doing this when enabling/disabling
      the entire display pipe.
      Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
      Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
      c9deac97
    • D
      drm/i915: copy&paste drm_crtc_helper_set_mode · a6778b3c
      Daniel Vetter 提交于
      Together with the static helper functions drm_crtc_prepare_encoders
      and drm_encoder_disable (which will be simplified in the next patch,
      but for now are 1:1 copies). Again, no changes beside new names for
      these functions.
      
      Also call our new set_mode instead of the crtc helper one now in all
      the places we've done so far.
      
      v2: Call the function just intel_set_mode to better differentia it
      from intel_crtc_mode_set which really only does the ->mode_set step of
      the entire modeset sequence on one crtc. Whereas this function does
      the global change.
      Acked-by: NJesse Barnes <jbarnes@virtuousgeek.org>
      Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
      a6778b3c
    • D
      drm/i915: clean up encoder_prepare/commit · 61b77ddd
      Daniel Vetter 提交于
      We no longer need them. And now that all encoders are converted, we
      can finally move the cpt modeset check to the right place - at the end
      of the crtc_enable function.
      Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
      Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
      61b77ddd
    • D
      drm/i915: convert dpms functions of dvo/sdvo/crt · b2cabb0e
      Daniel Vetter 提交于
      Yeah, big patch but I couldn't come up with a neat idea of how to
      split it up further, that wouldn't break dpms on cloned configs
      somehow. But the changes in dvo/sdvo/crt are all pretty much
      orthonogal, so it's not too bad a patch.
      
      These are the only encoders that support cloning, which requires a few
      special changes compared to the previous patches.
      - Compute the desired state of the display pipe by walking all
        connected encoders and checking whether any has active connectors.
        To make this clearer, drop the old mode parameter to the crtc dpms
        function and rename it to intel_crtc_update_dpms.
      - There's the curious case of intel_crtc->dpms_mode. With the previous
        patches to remove the overlay pipe A code and to rework the load
        detect pipe code, the big users are gone. We still keep it to avoid
        enabling the pipe twice, but we duplicate this logic with
        crtc->active, too. Still, leave this for now and just push a fake
        dpms mode into it that reflects the state of the display pipe.
      
      Changes in the encoder dpms functions:
      - We clamp the dpms state to the supported range right away. This is
        escpecially important for the VGA outputs, where only older hw
        supports the intermediate states. This (and the crt->adpa_reg patch)
        allows us to unify the crt dpms code again between all variants
        (gmch, vlv and pch).
      - We only enable/disable the output for dvo/sdvo and leave the encoder
        running. The encoder will be disabled/enabled when we switch the
        state of the entire output pipeline (which will happen right away
        for non-cloned setups). This way the duplication is reduced and
        strange interaction when disabling output ports at the wrong time
        avoided.
      
      The dpms code for all three types of connectors contains a bit of
      duplicated logic, but I think keeping these special cases separate is
      simpler: CRT is the only one that hanldes intermediate dpms state
      (which requires extra logic to enable/disable things in the right
      order), and introducing some abstraction just to share the code
      between dvo and sdvo smells like overkill. We can do that once someone
      bothers to implement cloning for the more modern outputs. But I doubt
      that this will ever happen.
      
      v2: s/crtc/crt/_set_dpms, noticed by Paulo Zanoni.
      Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
      Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
      b2cabb0e
    • D
      drm/i915/hdmi: convert to encoder->disable/enable · 5ab432ef
      Daniel Vetter 提交于
      I've picked hdmi as the first encoder to convert because it's rather
      simple:
      - no cloning possible
      - no differences between prepare/commit and dpms off/on switching.
      
      A few changes are required to do so:
      - Split up the dpms code into an enable/disable function and wire it
        up with the intel encoder.
      - Noop out the existing encoder prepare/commit functions used by the
        crtc helper - our crtc enable/disable code now calls back into the
        encoder enable/disable code at the right spot.
      - Create new helper functions to handle dpms changes.
      - Add intel_encoder->connectors_active to better track dpms state. Atm
        this is unused, but it will be useful to correctly disable the
        entire display pipe for cloned configurations. Also note that for
        now this is only useful in the dpms code - thanks to the crtc
        helper's dpms confusion across a modeset operation we can't (yet)
        rely on this having a sensible value in all circumstances.
      - Rip out the encoder helper dpms callback, if this is still getting
        called somewhere we have a bug. The slight issue with that is that
        the crtc helper abuses dpms off to disable unused functions. Hence
        we also need to implement a default encoder disable function to do
        just that with the new encoder->disable callback.
      - Note that we drop the cpt modeset verification in the commit
        callback, too. The right place to do this would be in the crtc's
        enable function, _after_ all the encoders are set up. But because
        not all encoders are converted yet, we can't do that. Hence disable
        this check temporarily as a minor concession to bisectability.
      
      v2: Squash the dpms mode to only the supported values -
      connector->dpms is for internal tracking only, we can hence avoid
      needless state-changes a bit whithout causing harm.
      
      v3: Apply bikeshed to disable|enable_ddi, suggested by Paulo Zanoni.
      Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
      Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
      5ab432ef
    • D
      drm/i915: add direct encoder disable/enable infrastructure · ef9c3aee
      Daniel Vetter 提交于
      Just prep work, not yet put to some use.
      
      Note that because we're still using the crtc helper to switch modes
      (and their complicated way to do partial modesets), we need to call
      the encoder's disable function unconditionally.
      
      But once this is cleaned up we shouldn't call the encoder's disable
      function unconditionally any more, because then we know that we'll
      only call it if the encoder is actually enabled. Also note that we
      then need to be careful about which crtc we're filtering the encoder
      list on: We want to filter on the crtc of the _current_ mode, not the
      one we're about to set up.
      
      For the enabling side we need to do the same trick. And again, we
      should be able to simplify this quite a bit when things have settled
      into place.
      
      Also note that this simply does not take cloning into account, so dpms
      needs to be handled specially for the few outputs where we even bother
      with it.
      Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
      Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
      ef9c3aee
  2. 17 8月, 2012 1 次提交
  3. 06 8月, 2012 2 次提交
  4. 26 7月, 2012 6 次提交
    • D
      drm/i915: rip out sanitize_pm again · acbe9475
      Daniel Vetter 提交于
      We believe to have squashed all issues around the gen6+ rps interrupt
      generation and why the gpu sometimes got stuck. With that cleared up,
      there's no user left for the sanitize_pm infrastructure, so let's just
      rip it out.
      
      Note that 'intel_reg_write 0xa014 0x13070000' is the w/a if we find
      ourselves stuck again.
      Acked-by: NChris Wilson <chris@chris-wilson.co.uk>
      Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
      acbe9475
    • C
      drm/i915: Avoid concurrent access when marking the device as idle/busy · f047e395
      Chris Wilson 提交于
      As suggested by Daniel, rip out the independent timers for device and
      crtc busyness and integrate the manual powermanagement of the display
      engine into the GEM core and its request tracking. The benefits are that
      the code is a lot smaller, fewer moving parts and should fit more neatly
      into the overall activity tracking of the driver.
      
      v2: Complete overhaul and removal of the racy timers and workers.
      Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
      Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
      f047e395
    • P
      drm/i915: add port field to struct intel_dp and use it · ab9d7c30
      Paulo Zanoni 提交于
      This will be needed for Haswell, but already has its uses here.
      
      This patch started as a small patch written patch by Shobhit Kumar,
      but it has changed so much that none of its original lines remain.
      
      Credits-to: Shobhit Kumar <shobhit.kumar@intel.com>
      Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
      Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
      ab9d7c30
    • D
      drm/i915: add port parameter to intel_hdmi_init · 08d644ad
      Daniel Vetter 提交于
      Instead of having a giant if cascade to figure this out according to
      the passed-in register. We could do quite a bit more cleaning up and
      all by using the port at more places, but I think this should be part
      of a bigger rework to introduce a struct intel_digital_port which
      would keep track of all these things. I guess this will be part of
      some haswell-DP-induced refactoring.
      
      For now this rips out the big cascade, which is what annoyed me so
      much.
      
      v2: Add port variable name back for the func decl (I've tried to trick
      myself below the 80 char limit).
      Reviewed-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
      Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
      08d644ad
    • D
      drm/i915: simplify possible_clones computation · 66a9278e
      Daniel Vetter 提交于
      Intel hw only has one MUX for encoders, so outputs are either not
      cloneable or all in the same group of cloneable outputs. This neatly
      simplifies the code and allows us to ditch some ugly if cascades in
      the dp and hdmi init code (well, we need these if cascades for other
      stuff still, but that can be taken care of in follow-up patches).
      
      Note that this changes two things:
      - dvo can now be cloned with sdvo, but dvo is gen2 whereas sdvo is
        gen3+, so no problem. Note that the old code had a bug and didn't
        allow cloning crt with dvo (but only the other way round).
      - sdvo-lvds can now be cloned with sdvo-non-tv. Spec says this won't
        work, but the only reason I've found is that you can't use the
        panel-fitter (used for lvds upscaling) with anything else. But we
        don't use the panel fitter for sdvo-lvds. Imo this part of Bspec is
        a) rather confusing b) mostly as a guideline to implementors (i.e.
        explicitly stating what is already implicit from the spec, without
        always going into the details of why). So I think we can ignore this
        - worst case we'll get a bug report from a user with with sdvo-lvds
        and sdvo-tmds and have to add that special case back in.
      
      Because sdvo lvds is a bit special explain in comments why sdvo LVDS
      outputs can be cloned, but native LVDS and eDP can't be cloned - we
      use the panel fitter for the later, but not for sdvo.
      
      Note that this also uncoditionally initializes the panel_vdd work used
      by eDP. Trying to be clever doesn't buy us anything (but strange bugs)
      and this way we can kill the is_edp check.
      
      v2: Incorporate review from Paulo
      - Add in a missing space.
      - Pimp comment message to address his concerns.
      Reviewed-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
      Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
      66a9278e
    • S
      drm/i915: Move DP structs to shared location · 54d63ca6
      Shobhit Kumar 提交于
      Move the DP structure to shared location so that it can be used from
      within the ddi module.
      
      Changes from Paulo:
      - Move less code to intel_drv.h
      - Remove #include statement
      - Replace a tab with a space in train_set
      Signed-off-by: NShobhit Kumar <shobhit.kumar@intel.com>
      Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
      Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
      54d63ca6
  5. 20 7月, 2012 2 次提交
  6. 05 7月, 2012 3 次提交
  7. 26 6月, 2012 1 次提交
  8. 14 6月, 2012 1 次提交
  9. 13 6月, 2012 1 次提交
    • D
      drm/i915: properly enable the blc controller on the right pipe · 24ded204
      Daniel Vetter 提交于
      On gen4+ we have a bitfield to specify from which pipe the backlight
      controller should take it's clock. For PCH split platforms we've
      already set these up, but only at initialization time. And without
      taking into account the 3rd pipe added with ivb.
      
      For gen4, we've completely ignored these. Although we do restrict lvds
      to the 2nd pipe, so this is only a problem on machines where we boot
      up with the lvds on the first pipe.
      
      So restructure the code to enable the backlight on the right pipe at
      modeset time.
      
      v2: For odd reasons panel_enable_backlight gets called twice in a
      modeset, so we can't WARN_ON in there if the backlight controller is
      switched on already.
      
      v3: backlight enable can also be called through dpms on, so the check
      in there is legit. Update the comment to reflect that.
      Tested-By: NKamal Mostafa <kamal@canonical.com>
      Bugzilla: https://bugs.launchpad.net/bugs/954661
      Cc: Carsten Emde <C.Emde@osadl.org>
      Reviewed-by: NEugeni Dodonov <eugeni.dodonov@intel.com>
      Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
      24ded204
  10. 05 6月, 2012 2 次提交
  11. 31 5月, 2012 1 次提交
    • P
      drm/i915: add set_infoframes to struct intel_hdmi · 687f4d06
      Paulo Zanoni 提交于
      We need a function that is able to fully 'set' the state of the DIP
      registers to a known state.
      
      Currently, we have the write_infoframe function that is called twice:
      once for AVI and once for SPD. The problem is that write_infoframe
      tries to keep the state of the DIP register as it is, changing only
      the minimum necessary bits. The second problem is that
      write_infoframe does twice (once for each time it is called) some
      work that should be done only once (like waiting for vblank and
      setting the port). If we add even more DIPs, it will do even more
      repeated work.
      
      This patch only adds the infrastructure keeping the code behavior the
      same as before.
      
      v2: add static keywords
      Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
      Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
      687f4d06
  12. 20 5月, 2012 7 次提交
    • D
      drm/i915: fixup infoframe support for sdvo · 81014b9d
      Daniel Vetter 提交于
      At least the worst offenders:
      - SDVO specifies that the encoder should compute the ecc. Testing also
        shows that we must not send the ecc field, so copy the dip_infoframe
        struct to a temporay place and avoid the ecc field. This way the avi
        infoframe is exactly 17 bytes long, which agrees with what the spec
        mandates as a minimal storage capacity (with the ecc field it would
        be 18 bytes).
      - Only 17 when sending the avi infoframe. The SDVO spec explicitly
        says that sending more data than what the device announces results
        in undefined behaviour.
      - Add __attribute__((packed)) to the avi and spd infoframes, for
        otherwise they're wrongly aligned. Noticed because the avi infoframe
        ended up being 18 bytes large instead of 17. We haven't noticed this
        yet because we don't use the uint16_t fields yet (which are the only
        ones that would be wrongly aligned).
      
      This regression has been introduce by
      
      3c17fe4b is the first bad commit
      commit 3c17fe4b
      Author: David Härdeman <david@hardeman.nu>
      Date:   Fri Sep 24 21:44:32 2010 +0200
      
          i915: enable AVI infoframe for intel_hdmi.c [v4]
      
      Patch tested on my g33 with a sdvo hdmi adaptor.
      
      Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=25732
      Tested-by: Peter Ross <pross@xvid.org> (G35 SDVO-HDMI)
      Reviewed-by: NEugeni Dodonov <eugeni.dodonov@intel.com>
      Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
      81014b9d
    • E
      drm/i915: prepare HDMI link for Haswell · 72662e10
      Eugeni Dodonov 提交于
      On Haswell, we need to properly train the DDI buffers prior to enabling
      HDMI, and enable the required clocks with correct dividers for the desired
      frequency.
      
      Also, we cannot simple reuse HDMI routines from previous generations of
      GPU, as most of HDMI-specific stuff is being done via the DDI port
      programming instead of HDMI-specific registers.
      
      This commit take advantage of the WR PLL clock table which is in a
      separate (previous) commit to select the right divisors for each mode.
      Signed-off-by: NEugeni Dodonov <eugeni.dodonov@intel.com>
      Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
      72662e10
    • E
      drm/i915: move HDMI structs to shared location · f5bbfca3
      Eugeni Dodonov 提交于
      Move intel_hdmi data structure and support functions to a shared location,
      to allow their usage from intel_ddi module.
      Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
      Signed-off-by: NEugeni Dodonov <eugeni.dodonov@intel.com>
      Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
      f5bbfca3
    • E
      drm/i915: detect digital outputs on Haswell · 0e72a5b5
      Eugeni Dodonov 提交于
      Digital port detection on Haswell is indicated by the presence of a bit in
      DDI_BUF_CTL for port A, and by a different register for ports B, C and D.
      So we check for those bits during the initialization time and let the hdmi
      function know about those.
      
      Note that this bit does not indicates whether the output is DP or HDMI.
      However, the DDI buffers can be programmed in a way that is shared between
      DP/HDMI and FDI/HDMI except for PORT E.
      
      So for now, we detect those digital outputs as being HDMI, but proper DP
      support is still pending.
      
      Note that DDI A can only drive eDP, so we do not handle it here for hdmi
      initialization.
      
      v2: simplify Haswell handling logic
      
      v3: use generic function for handling digital outputs.
      Signed-off-by: NEugeni Dodonov <eugeni.dodonov@intel.com>
      Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
      0e72a5b5
    • E
      drm/i915: program WM_LINETIME on Haswell · 1f8eeabf
      Eugeni Dodonov 提交于
      The line time can be programmed according to the number of horizontal
      pixels vs effective pixel rate ratio.
      
      v2: improve comment as per Chris Wilson suggestion
      
      v3: incorporate latest changes in specs.
      
      v4: move into wm update routine, also mention that the same routine can
      program IPS watermarks. We do not have their enablement code yet, nor
      handle the required clock settings at the moment, so this patch won't
      program those values for now.
      Signed-off-by: NEugeni Dodonov <eugeni.dodonov@intel.com>
      Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
      1f8eeabf
    • E
      drm/i915: support DDI training in FDI mode · c82e4d26
      Eugeni Dodonov 提交于
      Starting with Haswell, DDI ports can work in FDI mode to support
      connectivity with the outputs located on the PCH.
      
      This commit adds support for such connections in the intel_ddi module, and
      provides Haswell-specific functionality to make it work.
      
      v2: simplify the commit as per Daniel Vetter suggestion.
      Signed-off-by: NEugeni Dodonov <eugeni.dodonov@intel.com>
      Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
      c82e4d26
    • E
      drm/i915: initialize DDI buffer translations · 45244b87
      Eugeni Dodonov 提交于
      DDI is introduced starting with Haswell GPU generation. So to simplify its
      management in the future, we also add intel_ddi.c to hold all the
      DDI-related items.
      
      Buffer translations for DDI links must be initialized prior to enablement.
      For FDI and DP, first 9 pairs of values are used to select the connection
      parameters. HDMI uses the last pair of values and ignores the first 9
      pairs. So we program HDMI values in both cases, which allows HDMI to work
      over both FDI and DP-friendly buffers.
      Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
      Signed-off-by: NEugeni Dodonov <eugeni.dodonov@intel.com>
      Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
      45244b87