It's bogus.
If I've followed the history of this piece of code correctly, i.e. the
initial register write with the following vblank wait, this goes all
the way back to the original enabling of DP support in
commit a4fc5ed698
Author: Keith Packard <keithp@keithp.com>
Date: Tue Apr 7 16:16:42 2009 -0700
drm/i915: Add Display Port support
Unfortunately it seems to be nothing more than glorified duct-tape and
sometimes actively harmful. Adam Jackson noticed this for CPT
platforms with
commit e85194641b
Author: Adam Jackson <ajax@redhat.com>
Date: Thu Jul 21 17:48:38 2011 -0400
drm/i915/dp: Don't turn CPT DP ports on too early
Unfortunately this kept the code around for ilk and gm45.
The specific failure case I'm seeing here is that after a dpms off/on
cycle we have the bits from the last link training (hopefully
successful link training) set in intel_dp->DP. This is requiered so
that complete_link_train can enable the port with the right tuning
values.
Unfortunately writing these again to the disabled port at dpms on time
kills the port somehow until it's disabled - dp link training fails in
an endless loop without this patch on my mobile ilk and gm45.
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Tested-by: Chris Wilson <chris@chris-wilson.co.uk>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=51493
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
As a quick reference I'll detail the motivation and design of the new code a
bit here (mostly stitched together from patchbomb announcements and commits
introducing the new concepts).
The crtc helper code has the fundamental assumption that encoders and crtcs can
be enabled/disabled in any order, as long as we take care of depencies (which
means that enabled encoders need an enabled crtc to feed them data,
essentially).
Our hw works differently. We already have tons of ugly cases where crtc code
enables encoder hw (or encoder->mode_set enables stuff that should only be
enabled in enocder->commit) to work around these issues. But on the disable
side we can't pull off similar tricks - there we actually need to rework the
modeset sequence that controls all this. And this is also the real motivation
why I've finally undertaken this rewrite: eDP on my shiny new Ivybridge
Ultrabook is broken, and it's broken due to the wrong disable sequence ...
The new code introduces a few interfaces and concepts:
- Add new encoder->enable/disable functions which are directly called from the
crtc->enable/disable function. This ensures that the encoder's can be
enabled/disabled at a very specific in the modeset sequence, controlled by our
platform specific code (instead of the crtc helper code calling them at a time
it deems convenient).
- Rework the dpms code - our code has mostly 1:1 connector:encoder mappings and
does support cloning on only a few encoders, so we can simplify things quite a
bit.
- Also only ever disable/enable the entire output pipeline. This ensures that
we obey the right sequence of enabling/disabling things, trying to be clever
here mostly just complicates the code and results in bugs. For cloneable
encoders this requires a bit of special handling to ensure that outputs can
still be disabled individually, but it simplifies the common case.
- Add infrastructure to read out the current hw state. No amount of careful
ordering will help us if we brick the hw on the initial modeset setup. Which
could happen if we just randomly disable things, oblivious to the state set up
by the bios. Hence we need to be able to read that out. As a benefit, we grow a
few generic functions useful to cross-check our modeset code with actual hw
state.
With all this in place, we can copy&paste the crtc helper code into the
drm/i915 driver and start to rework it:
- As detailed above, the new code only disables/enables an entire output pipe.
As a preparation for global mode-changes (e.g. reassigning shared resources) it
keeps track of which pipes need to be touched by a set of bitmasks.
- To ensure that we correctly disable the current display pipes, we need to
know the currently active connector/encoder/crtc linking. The old crtc helper
simply overwrote these links with the new setup, the new code stages the new
links in ->new_* pointers. Those get commited to the real linking pointers once
the old output configuration has been torn down, before the ->mode_set
callbacks are called.
- Finally the code adds tons of self-consistency checks by employing the new hw
state readout functions to cross-check the actual hw state with what the
datastructure think it should be. These checks are done both after every
modeset and after the hw state has been read out and sanitized at boot/resume
time. All these checks greatly helped in tracking down regressions and bugs in
the new code.
With this new basis, a lot of cleanups and improvements to the code are now
possible (besides the DP fixes that ultimately made me write this), but not yet
done:
- I think we should create struct intel_mode and use it as the adjusted mode
everywhere to store little pieces like needs_tvclock, pipe dithering values or
dp link parameters. That would still be a layering violation, but at least we
wouldn't need to recompute these kinds of things in intel_display.c. Especially
the port bpc computation needed for selecting the pipe bpc and dithering
settings in intel_display.c is rather gross.
- In a related rework we could implement ->mode_valid in terms of ->mode_fixup
in a generic way - I've hunted down too many bugs where ->mode_valid did the
right thing, but ->mode_fixup didn't. Or vice versa, resulting in funny bugs
for user-supplied modes.
- Ditch the idea to rework the hdp handling in the common crtc helper code and
just move things to i915.ko. Which would rid us of the ->detect crtc helper
dependencies.
- LVDS wire pair and pll enabling is all done in the crtc->mode_set function
currently. We should be able to move this to the crtc_enable callbacks (or in
the case of the LVDS wire pair enabling, into some encoder callback).
Last, but not least, this new code should also help in enabling a few neat
features: The hw state readout code prepares (but there are still big pieces
missing) for fastboot, i.e. avoiding the inital modeset at boot-up and just
taking over the configuration left behind by the bios. We also should be able
to extend the configuration checks in the beginning of the modeset sequence and
make better decisions about shared resources (which is the entire point behind
the atomic/global modeset ioctl).
Tested-by: Jani Nikula <jani.nikula@intel.com>
Tested-by: Ben Widawsky <ben@bwidawsk.net>
Tested-by: Damien Lespiau <damien.lespiau@intel.com>
Tested-by: Rodrigo Vivi <rodrigo.vivi@gmail.com>
Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
Tested-by: Vijay Purushothaman <vijay.a.purushothaman@intel.com>
Acked-by: Vijay Purushothaman <vijay.a.purushothaman@intel.com>
Tested-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Acked-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Tested-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Now that we have solid modeset state tracking and checking code in
place, we can do the Full Monty also after dpms calls.
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Because that's what it is. Unfortunately we can't rip this out because
the fb helper has an incetious relationship with the crtc helper - it
likes to call disable_unused_functions, among other things.
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
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: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
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: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Also add some macros to make the pipe computation a bit easier.
v2: I've mixed up the CPT and !CPT PORT_TO_PIPE macro variants ...
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
With the new infrastructure we're doing this when enabling/disabling
the entire display pipe.
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
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: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
DP is the first encoder which isn't simple. As
commit d240f20f54
Author: Jesse Barnes <jbarnes@virtuousgeek.org>
Date: Fri Aug 13 15:43:26 2010 -0700
drm/i915: make sure eDP PLL is enabled at the right time
discovered, we need to enable the eDP PLL for the cpu port _before_ we
enable the pipes and planes. After a few more commits the current
solution is to enable the PLL in the dp mode_set function (because
this is the only encoder callback the crtc helper code calls before it
calls the crtc's commit function).
Now I suspect that we actually should enable/disable the entire cpu
eDP port before/after planes, but thanks to how the crtc helper code
assumes that you can disable an encoder without disabling it's crtc
right away, this won't work.
The result is that the current prepare/commit hooks don't touch the
eDP PLL, but instead it get's frobbed in dp_mode_set and in the dp
dpms function. Hence we need to keep things (at least for now)
bug-for-bug compatible by using our own special dp dpms function and
keep everything else more-or-less as-is (just using our own
infrastrucutre now).
This mess can only be cleaned up once we control the entire modeset
sequence and can move things around freely.
v2: Squash unsupported dpms modes to OFF at the beginning of the DP
dpms function.
v3: Need to set the dpms state to off in dp_disable, otherwise this
breaks the newly added WARNs ...
v4: Rebased against edp panel off sequence changes in 3.6-rc2
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Daniel writes:
"New stuff for -next. Highlights:
- prep patches for the modeset rework. Note that one of those patches
touches the fb helper in the common drm code.
- hasw hdmi audio support (Wang Xingchao)
- improved instdone dumping for gen7 (Ben)
- unbound tracking and a few follow-up patches from Chris
- dma_buf->begin/end_cpu_access plus fix for drm/udl (Dave)
- improve mmio error reporting for hsw
- prep patch for WQ_NON_REENTRANT removal (Tejun Heo)
"
* 'for-airlied' of git://people.freedesktop.org/~danvet/drm-intel: (41 commits)
drm/i915: Remove __GFP_NO_KSWAPD
drm/i915: disable rc6 on ilk when vt-d is enabled
drm/i915: Avoid unbinding due to an interrupted pin_and_fence during execbuffer
drm/i915: Use new INSTDONE registers (Gen7+)
drm/i915: Add new INSTDONE registers
drm/i915: Extract reading INSTDONE
drm/i915: Use a non-blocking wait for set-to-domain ioctl
drm/i915: Juggle code order to ease flow of the next patch
drm/i915: Use cpu relocations if the object is in the GTT but not mappable
drm/i915: Extract general object init routine
drm/i915: Protect private gem objects from truncate (such as imported dmabuf)
drm/i915: Only pwrite through the GTT if there is space in the aperture
i915: use alloc_ordered_workqueue() instead of explicit UNBOUND w/ max_active = 1
drm/i915: Find unclaimed MMIO writes.
drm/i915: Add ERR_INT to gen7 error state
drm/i915: Cantiga+ cannot handle a hsync front porch of 0
drm/i915: fix reassignment of variable "intel_dp->DP"
drm/i915: Try harder to allocate an mmap_offset
drm/i915: Show pin count in debugfs
drm/i915: Show (count, size) of purgeable objects in i915_gem_objects
...
Neither the drm core nor any of the drivers really need the raw_edid field
of struct drm_display_info for anything. Instead of being useful, it
creates confusion about who is responsible for freeing the memory it points
to and setting the field to NULL afterwards, leading to memory leaks and
dangling pointers.
Remove the raw_edid field, and fix drivers as necessary.
Reported-by: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Acked-by: Inki Dae <inki.dae@samsung.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
In intel_dp_mode_set we OR in the exact same bits twice at the same
spot. Kill one of the redundant assignments.
This little regression was introduced by:
commit 417e822dee
Author: Keith Packard <keithp@keithp.com>
Date: Tue Nov 1 19:54:11 2011 -0700
drm/i915: Treat PCH eDP like DP in most places
PCH eDP has many of the same needs as regular PCH DP connections,
including the DP_CTl bit settings, the TRANS_DP_CTL register.
The reachable tag for this commit is: v3.1-5461-g417e822
Signed-off-by: Anhua Xu <anhua.xu@intel.com>
[danvet: Improved the commit message somewhat and ensured the diff is
clearer.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Backmerge Linux 3.6-rc2 to resolve a few funny conflicts before we put
even more madness on top:
- drivers/gpu/drm/i915/i915_irq.c: Just a spurious WARN removed in
-fixes, that has been changed in a variable-rename in -next, too.
- drivers/gpu/drm/i915/intel_ringbuffer.c: -next remove scratch_addr
(since all their users have been extracted in another fucntion),
-fixes added another user for a hw workaroudn.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
eDP is tons of fun. It turns out that at least the new MacBook Air 5,1
model absolutely doesn't like the new force vdd dance we've introduced
in
commit 6cb49835da
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date: Sun May 20 17:14:50 2012 +0200
drm/i915: enable vdd when switching off the eDP panel
But that patch also tried to fix some neat edp sequence issue with the
force_vdd timings. Closer inspection reveals that we've raised
force_vdd only to do the aux channel communication dp_sink_dpms. If we
move the edp_panel_off below that, we don't need any force_vdd for the
disable sequence, which makes the Air happy.
Unfortunately the reporter of the original bug that the above commit
fixed is travelling, so we can't test whether this regresses things.
But my theory is that since we don't check for any power-off ->
force_vdd-on delays in edp_panel_vdd_on, this was the actual
root-cause of this failure. With that force_vdd dance completely
eliminated, I'm hopeful the original bug stays fixed, too.
For reference the old bug, which hopefully doesn't get broken by this:
https://bugzilla.kernel.org/show_bug.cgi?id=43163
In any case, regression fixers win over plain bugfixes, so this needs
to go in asap.
v2: The crucial pieces seems to be to clear the force_vdd flag
uncoditionally, too, in edp_panel_off. Looks like this is left behind
by the firmware somehow.
v3: The Apple firmware seems to switch off the panel on it's own, hence
we still need to keep force_vdd on, but properly clear it when switching
the panel off.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=45671
Tested-by: Roberto Romer <sildurin@gmail.com>
Tested-by: Daniel Wagner <wagi@monom.org>
Tested-by: Keith Packard <keithp@keithp.com>
Cc: stable@vger.kernel.org
Cc: Keith Packard <keithp@keithp.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
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: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
We have some common code that we always run before calling
intel_dp_set_link_train. This common code sets the correct training
patterns to the DP variable. If we add more calls to
intel_dp_set_link_train, we'll also have to duplicate this common
code. So instead of repeating this code whenever we call
intel_dp_set_link_train, we move the code to inside the function: now
we check which training pattern we're going to set and then we set the
DP register according to it.
One of the side-effects of this change is that now we never forget to
mask the training pattern bits before changing them. It looks like
this was working before because we were first masking the bits, then
writing 00, 01 and then 11.
This patch also enables us to use the intel_dp_set_link_train function
when disabling link training: in this case we need to avoid writing
the DP_TRAINING_LANE*_SET AUX commands.
As a bonus, the big intel_dp_{start,complete}_link_train functions
will get smaller and a little bit easier to read.
Version 2 changes:
- Rewrite commit message.
- Also clear the training pattern bits before changing them.
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
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: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
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: Shobhit Kumar <shobhit.kumar@intel.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
While debugging Haswell link train failures I observed that we never
try the maximum voltage configuration more than once consecutively. We
start the training, the monitor keeps telling us to increase the
voltage, then when we reach the maximum we just go back to the start
(because of the "memset" above "voltage_tries = 0"). When we reach
this point, we keep alternating between the maximum and the minimum
voltages until we give up.
The DP spec suggests that we should try the same voltage 5 times
before giving up. This patch makes us try the maximum voltage at
least 5 times before going back to the minimum voltages.
This patch does not fix any particular bug I'm aware of.
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
We already have this pattern at quite a few places, and moving part of
the modeset helper stuff into the driver will add more.
v2: Don't clobber the crtc struct name with the macro parameter ...
v3: Convert two more places noticed by Paulo Zanoni.
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
High frequency link configurations have the potential to cause trouble
with long and/or cheap cables, so prefer slow and wide configurations
instead. This patch has the potential to cause trouble for eDP
configurations that lie about available lanes, so if we run into that we
can make it conditional on eDP.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=45801
Tested-by: peter@colberg.org
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
I want to merge the "no more fake agp on gen6+" patches into
drm-intel-next (well, the last pieces). But a patch in 3.5-rc4 also
adds a new use of dev->agp. Hence the backmarge to sort this out, for
otherwise drm-intel-next merged into Linus' tree would conflict in the
relevant code, things would compile but nicely OOPS at driver load :(
Conflicts in this merge are just simple cases of "both branches
changed/added lines at the same place". The only tricky part is to
keep the order correct wrt the unwind code in case of errors in
intel_ringbuffer.c (and the MI_DISPLAY_FLIP #defines in i915_reg.h
together, obviously).
Conflicts:
drivers/gpu/drm/i915/i915_reg.h
drivers/gpu/drm/i915/intel_ringbuffer.c
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
They aren't going anywhere, and probing on DDC can cause the panel to
blank briefly, so read them up front and cache them for later queries.
v2: fix potential NULL derefs in intel_dp_get_edid_modes and
intel_dp_get_edid (Jani)
copy full EDID length, including extension blocks (Takashi)
free EDID on teardown (Takashi)
v3: malloc a new EDID buffer that's big enough for the memcpy (Chris)
v4: change handling of NULL EDIDs, just preserve the NULL behavior
across detects and mode list fetches rather than trying to re-fetch
the EDID (Chris)
v5: be glad that Chris is around to remind me to hit C-x C-s before
committing.
References: https://bugs.freedesktop.org/show_bug.cgi?id=46856
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Daniel Vetter
Dave Airlie
Jani Nikula
Xu, Anhua
Paulo Zanoni
Shobhit Kumar
Laurent Pinchart
Jesse Barnes