Imre Deak [Wed, 20 Apr 2016 17:27:54 +0000 (20:27 +0300)]
drm/i915: Inline intel_suspend_complete
Initially we thought that the platform specific suspend/resume sequences
can be shared between the runtime and system suspend/resume handlers.
This turned out to be not true, we have quite a few differences on most
of the platforms. This was realized already earlier by Paulo who
inlined the platform specific resume_prepare handlers. We have the
same problem with the corresponding suspend_complete handlers, there are
platform differences that make it unfeasible to share the code between
the runtime and system suspend paths. Also now we call functions that
need to be paired like hsw_enable_pc8()/hsw_disable_pc8() from different
levels of the call stack, which is confusing. Fix this by inlining the
suspend_complete handlers too.
This is also needed by the next patch that removes a redundant
uninit/init call during system suspend/resume on BXT.
Imre Deak [Tue, 19 Apr 2016 10:00:36 +0000 (13:00 +0300)]
drm/i915/kbl: Don't WARN for expected secondary MISC IO power well request
In commit 5f304c873634 ("drm/i915/kbl: Reset secondary power well requests
left on by DMC/KVMR") I forgot about the fact that SKL==KBL most of the
time and that a secondary MISC IO power well request left on by the DMC is
"expected". Tune down the corresponding WARN to be a debug message. This
was caught by CI suspend tests.
Mika Kahola [Wed, 20 Apr 2016 12:39:02 +0000 (15:39 +0300)]
drm/i915: Fix eDP low vswing for Broadwell
It was noticed on bug #94087 that module parameter
i915.edp_vswing=2 that should override the VBT setting
to use default voltage swing (400 mV) was not applied
for Broadwell.
This patch provides a fix for this by checking if default
i.e. higher voltage swing is requested to be used and
applies the DDI translations table for DP instead of eDP
(low vswing) table.
v2: Combine two if statements into one (Jani)
v3: Change dev_priv->edp_low_vswing to use dev_priv->vbt.edp.low_vswing
Dave Gordon [Tue, 12 Apr 2016 13:46:16 +0000 (14:46 +0100)]
drm/i915: check for ERR_PTR from i915_gem_object_pin_map()
The newly-introduced function i915_gem_object_pin_map() returns an
ERR_PTR (not NULL) if the pin-and-map opertaion fails, so that's what we
must check for. And it's nicer not to assign such a pointer-or-error to
a structure being filled in until after it's been validated, so we
should keep it local and avoid exporting a bogus pointer. Also, for
clarity and symmetry, we should clear 'virtual_start' along with 'vma'
when unmapping a ringbuffer.
Signed-off-by: Dave Gordon <david.s.gordon@intel.com> Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Alex Dai [Tue, 19 Apr 2016 15:08:35 +0000 (16:08 +0100)]
drm/i915/guc: drop cached copy of 'wq_head'
Now that we keep the GuC client process descriptor permanently mapped,
we don't really need to keep a local copy of the GuC's work-queue-head.
So we can simplify the code a little by not doing this.
Signed-off-by: Alex Dai <yu.dai@intel.com> Signed-off-by: Dave Gordon <david.s.gordon@intel.com> Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Dave Gordon [Tue, 19 Apr 2016 15:08:34 +0000 (16:08 +0100)]
drm/i915/guc: keep GuC doorbell & process descriptor mapped in kernel
Don't use kmap_atomic() for doorbell & process descriptor access.
This patch fixes the BUG shown below, where the thread could sleep
while holding a kmap_atomic mapping. In order not to need to call
kmap_atomic() in this code path, we now set up a permanent kernel
mapping of the shared doorbell and process-descriptor page, and
use that in all doorbell and process-descriptor related code.
Chris Wilson [Wed, 20 Apr 2016 11:09:52 +0000 (12:09 +0100)]
drm/i915/shrinker: Only shmemfs objects are backed by swap
Since we can only swap out shmemfs objects, those are the only ones that
can influence the ability of the shrinker to free pages. Currently, all
non-shmemfs objects have a raised pages_pin_count to protect them from
the shrinker, so this just makes the logic for can_release_pages()
clearer (and safer in future so that we don't over estimate our ability
to free up pages from future non-swappable objects).
Chris Wilson [Wed, 20 Apr 2016 11:09:51 +0000 (12:09 +0100)]
drm/i915/shrinker: Report "unevictable" pages
Inside the shrinker we call can_release_pages() to indicate whether or
not we can make forward progress in freeing up memory by unbinding that
object. When adding our report to oom, we should be using the same
logic.
Whilst here, change the reporting from bytes to pages so that it looks
smaller to the user!, is consistent with the neighbouring oom report
itself which displays counts in pages, and makes the unsigned long
overflow less likely.
Chris Wilson [Wed, 20 Apr 2016 11:09:50 +0000 (12:09 +0100)]
drm/i915/shrinker: Only report objects with extra pinned pages as pinned
When iterating over the bound list, we expect all objects there to have
their pages pinned (by the bound VMA). So only report those objects with
additional pin count on their pages as "pinned". These should be those
objects used for display and hardware access.
drm/i915/gen8+: Do not enable DPF interrupt since the handler does not exist
Looks like DPF was not implemented for gen8+ but the IER and IMR
are still enabled on initialization.
Since there is no code to handle this interrupt, gate the irq
enablement behind HAS_L3_DPF in case the feature gets enabled
in the future.
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
drm/i915: Fixing eDP detection on certain platforms
Since commit 30d9aa4265fe ("drm/i915: Read sink_count dpcd always"),
the status of a DP connector depends on its sink count value.
However, some eDP panels don't set that value appropriately,
causing them to be reported as disconnected.
Fix this by ignoring sink count for eDP.
v2: Rephrased commit message. (Ander)
In case of eDP, returning status as connected if DPCD
read succeeds to avoid any further operations.
Fixes: 30d9aa4265fe ("drm/i915: Read sink_count dpcd always") Cc: Ander Conselvan De Oliveira <conselvan2@gmail.com> Cc: Jani Nikula <jani.nikula@linux.intel.com> Reported-by: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com> Signed-off-by: Sivakumar Thulasimani <sivakumar.thulasimani@intel.com> Signed-off-by: Shubhangi Shrivastava <shubhangi.shrivastava@intel.com> Tested-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Reviewed-by: Ander Conselvan de Oliveira <conselvan2@gmail.com> Signed-off-by: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/1460444034-22320-1-git-send-email-shubhangi.shrivastava@intel.com
drm/i915/dp/mst: Fix MST logic in intel_dp_long_pulse()
In commit 7d23e3c37bb3 ("drm/i915: Cleaning up intel_dp_hpd_pulse") some
much needed clean-up was done, but unfortunately part of the change
broke DP MST. The real issue was setting the connector state to
disconnected in the MST case, which is good, but the code then (after
a goto) checks if the connector state is not connected and shuts down
MST if this is the case, which is bad. With this change both SST and
MST seem to be happy.
v2: Add removed check further up in the function to be sure that MST
is shut down when we lose the link. (Ander)
Fixes: commit 7d23e3c37bb3 ("drm/i915: Cleaning up intel_dp_hpd_pulse")
cc: Sivakumar Thulasimani <sivakumar.thulasimani@intel.com>
cc: Shubhangi Shrivastava <shubhangi.shrivastava@intel.com>
cc: Ander Conselvan de Oliveira <conselvan2@gmail.com>
cc: Nathan D Ciobanu <nathan.d.ciobanu@intel.com> Signed-off-by: Jim Bride <jim.bride@linux.intel.com> Reviewed-by: Ander Conselvan de Oliveira <conselvan2@gmail.com> Reviewed-by: Lyude <cpaul@redhat.com> Signed-off-by: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/1460394684-7036-1-git-send-email-jim.bride@linux.intel.com
Do not use magic numbers, do not prefix stuff with "PCI_", do not
declare registers in implementation files. Also move the PCI
registers under correct comment in i915_reg.h.
v2:
- Consistently use BSM (not BDSM or other variants from PRM) (Chris)
- Also include register address to help identify the register (Chris)
v3:
- Refer to register value as *_val instead of *_reg (Chris)
v4:
- Make style checker happy
Cc: Jani Nikula <jani.nikula@intel.com> Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Ville Syrjälä [Mon, 18 Apr 2016 11:02:28 +0000 (14:02 +0300)]
drm/i915: Define HSW/BDW display power domains the right way up
Currently we're trying to define HSW/BDW power wells by what's not
included. Let's do it the other way around, so that you can actually
tell when the power well would get enabled. This will also allow us to
add new power domains without accidentally adding it to the HSW/BDW
display power domains.
The current set of domains looks rather buggy even:
- POWER_DOMAIN_MODESET is included in the display power well needlessly
- DDI-B to DDI-E were not part of the display power well when they
should be
Ville Syrjälä [Mon, 18 Apr 2016 11:02:27 +0000 (14:02 +0300)]
drm/i915: Define VLV/CHV display power well domains properly
Currently we're using POWER_DOMAIN_MASK as the power domains for the
display power well on VLV/CHV. That includes all power domains even
though the disp2d/pipe-a power well is not needed for a lot of things.
Let's reduce these to what we actually need.
Ville Syrjälä [Mon, 18 Apr 2016 11:02:26 +0000 (14:02 +0300)]
drm/i915: Set .domains=POWER_DOMAIN_MASK for the always-on well
The always-on well is the same as runtime PM, so we should just
"enable" it for any power domain. Throw out the usless
FOO_ALWAYS_ON_DOMAINS defines and just use POWER_DOMAIN_MASK.
Ville Syrjälä [Mon, 18 Apr 2016 17:34:04 +0000 (20:34 +0300)]
drm/i915: Fix oops in vlv_force_pll_on()
intel_pipe_will_have_type() doesn't just look at the passied in
pipe_config, instead it expects there to be a full atomic state behind
it. Obviously that won't go so well when vlv_force_pll_on() just uses a
temp pipe_config. Fix things by using pipe_config->has_dsi_encoder
instead intel_pipe_will_have_type(INTEL_OUTPUT_DSI) to check if we need
to actually enable the DPLL.
The regressing patch wasn't exactly new (as in first posted more than
six months ago), so I'm a bit baffled how I didn't manage to hit this
myself so far.
Cc: Jani Nikula <jani.nikula@intel.com> Cc: Marius Vlad <marius.c.vlad@intel.com> Reported-by: Marius Vlad <marius.c.vlad@intel.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=94995 Fixes: cd2d34d9b61f ("drm/i915: Setup DPLL/DPLLMD for DSI too on VLV/CHV") Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/1461000844-20543-1-git-send-email-ville.syrjala@linux.intel.com Tested-by: Marius Vlad <marius.c.vlad@intel.com> Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Imre Deak [Mon, 18 Apr 2016 11:48:21 +0000 (14:48 +0300)]
drm/i915/gen9: Fix runtime PM refcounting in case DMC firmware isn't loaded
While we disable runtime PM and with that display power well support if
the DMC firmware isn't loaded, we still want to disable power wells
during system suspend and driver unload. So drop/reacquire the
corresponding power refcount during suspend/resume and driver unloading.
This also means we have to check if DMC is not loaded and skip enabling
DC states in the power well code.
v2:
- Reuse intel_csr_ucode_suspend() in intel_csr_ucode_fini() instead of
opencoding the former. (Chris)
- Add docbook comment to the public resume and suspend functions.
Imre Deak [Mon, 18 Apr 2016 07:04:21 +0000 (10:04 +0300)]
drm/i915/ddi: Fix eDP VDD handling during booting and suspend/resume
The driver's VDD on/off logic assumes that whenever the VDD is on we
also hold an AUX power domain reference. Since BIOS can leave the VDD on
during booting and resuming and on DDI platforms we won't take a
corresponding power reference, the above assumption won't hold on those
platforms and an eventual delayed VDD off work will do an extraneous AUX
power domain put resulting in a refcount underflow. Fix this the same
way we did this for non-DDI DP encoders:
commit 6d93c0c41760c0 ("drm/i915: fix VDD state tracking after system
resume")
At the same time call the DP encoder suspend handler the same way as the
non-DDI DP encoders do to flush any pending VDD off work. Leaving the
work running may cause a HW access where we don't expect this (at a point
where power domains are suspended already).
While at it remove an unnecessary function call indirection.
This fixed for me AUX refcount underflow problems on BXT during
suspend/resume.
Imre Deak [Mon, 18 Apr 2016 11:45:54 +0000 (14:45 +0300)]
drm/i915: Fix system resume if PCI device remained enabled
During system resume we depended on pci_enable_device() also putting the
device into PCI D0 state. This won't work if the PCI device was already
enabled but still in D3 state. This is because pci_enable_device() is
refcounted and will not change the HW state if called with a non-zero
refcount. Leaving the device in D3 will make all subsequent device
accesses fail.
This didn't cause a problem most of the time, since we resumed with an
enable refcount of 0. But it fails at least after module reload because
after that we also happen to leak a PCI device enable reference: During
probing we call drm_get_pci_dev() which will enable the PCI device, but
during device removal drm_put_dev() won't disable it. This is a bug of
its own in DRM core, but without much harm as it only leaves the PCI
device enabled. Fixing it is also a bit more involved, due to DRM
mid-layering and because it affects non-i915 drivers too. The fix in
this patch is valid regardless of the problem in DRM core.
v2:
- Add a code comment about the relation of this fix to the freeze/thaw
vs. the suspend/resume phases. (Ville)
- Add a code comment about the inconsistent ordering of set power state
and device enable calls. (Chris)
Imre Deak [Fri, 15 Apr 2016 19:32:58 +0000 (22:32 +0300)]
drm/i915/kbl: Reset secondary power well requests left on by DMC/KVMR
The workaround added in
commit c6782b76d31a ("drm/i915/gen9: Reset secondary power well
requests left on by DMC/KVMR")
needs to be applied on Kabylake too as shown by the corresponding
timeout errors about power well 1 and MISC IO power well disabling in
the latest CI run.
Ville Syrjälä [Mon, 18 Apr 2016 11:29:32 +0000 (14:29 +0300)]
drm/i915: Replace nondescript 'WARN_ON(!lret)' with a sensible error message
When a vblank wait times out in intel_atomic_wait_for_vblanks() we just
get a cryptic 'WARN_ON(!ret)' backtrace in dmesg. Repace it with
something that tells you what actually happened.
Chris Wilson [Sun, 17 Apr 2016 19:42:46 +0000 (20:42 +0100)]
drm/i915: Avoid stalling on pending flips for legacy cursor updates
The legacy cursor ioctl expects to be asynchronous with respect to other
screen updates, in particular page flips. As X updates the cursor from a
signal context, if the cursor blocks then it will stall both the input
and output chains causing bad stuttering and horrible UX.
Reported-and-tested-by: Rafael Ristovski <rafael.ristovski@gmail.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=94980 Fixes: 5008e874edd34 ("drm/i915: Make wait_for_flips interruptible.") Suggested-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Jani Nikula <jani.nikula@intel.com> Cc: stable@vger.kernel.org Link: http://patchwork.freedesktop.org/patch/msgid/1460922166-20292-1-git-send-email-chris@chris-wilson.co.uk Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch> Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Jani Nikula [Fri, 15 Apr 2016 12:47:31 +0000 (15:47 +0300)]
drm/i915/dsi: fix CHV dsi encoder hardware state readout on port C
Due to "some hardware limitation" the DPI enable bit in port C control
register does not get set on VLV. As a workaround we check the status in
pipe B conf register instead. The workaround was added in
drm/i915: Software workaround for getting the HW status of DSI Port C on BYT
Empirical evidence (on Surface 3 with DSI on port C per VBT) shows that
this is the case also on CHV, so extend the workaround to CHV. We still
have the device ready register check in place, so this should not get
confused with e.g. HDMI on pipe B.
This fixes a number of state checker warnings on CHV DSI port C.
Reflect the status of obj->mapping as added with the
i915_gem_object_pin_map API.
'M' was chosen to designate the pin mapped status.
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Cc: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Ville Syrjälä [Tue, 12 Apr 2016 19:14:38 +0000 (22:14 +0300)]
drm/i915: Reject 'Center' scaling mode for eDP/DSI on GMCH platforms
We don't have a LVDS_BORDER_ENABLE type of bit for either eDP or DSI,
and just trying to frob the display timings to include borders results
in a corrupted picture. So reject the 'Center' scaling mode on GMCH
platforms for eDP and DSI.
TODO: Should really filter out the unsupported modes from the prop,
but that would be fairly invasive since the prop is now created and
stored by drm core. So leave it for a rainy day.
Ville Syrjälä [Tue, 12 Apr 2016 19:14:35 +0000 (22:14 +0300)]
drm/i915: Compute DSI PLL parameters during .compute_config()
Compute the DSI PLL parameters during .compute_config() rather than
.pre_pll_enable() so that we can fail gracefully if we can't find
suitable parameters.
In order to do that we need to store the DSI PLL parameters in
pipe_config.
Ville Syrjälä [Tue, 12 Apr 2016 19:14:34 +0000 (22:14 +0300)]
drm/i915: Setup DPLL/DPLLMD for DSI too on VLV/CHV
Set up DPLL and DPLL_MD even when driving DSI output on VLV/CHV. While
the DPLL isn't used to provide the clock we still need the refclock, and
it appears that the pixel repeat factor also has an effect on DSI
output. So set up eveyrhing in DPLL and DPLL_MD as we would do for
DP/HDMI/VGA, but don't actually enable the DPLL or configure the
dividers via DPIO.
drm/i915/bxt: Reversed polarity of PORT_PLL_REF_SEL bit
This reversed bit polarity is actually common
for all BXT and APL SoCs. Therefore, revision checking
in the original commit should be removed to make
the bit set regardless of revision ID of GFX block.
Imre Deak [Mon, 4 Apr 2016 14:27:10 +0000 (17:27 +0300)]
drm/i915/bxt: Add HW state verification for DDI PHY and CDCLK
I caught a few errors in our current PHY/CDCLK programming by sanity
checking the actual programmed state, so I thought it would be also
useful for the future. In addition to verifying the state after
programming it also verify it after exiting DC5, to make sure DMC
restored/kept intact everything related.
v2:
- Inlining __phy_reg_verify_state() doesn't make sense and also
incorrect, so don't do it (PW/CI gcc)
v3:
- Rebase on latest -nightly
Imre Deak [Fri, 1 Apr 2016 13:02:44 +0000 (16:02 +0300)]
drm/i915/bxt: Don't reprogram an already enabled DDI PHY
If BIOS has already programmed and enabled a PHY, don't reprogram it as
that may interfere with the currently active outputs. A follow-up patch
will add state verification, so we can catch any misconfiguration on
BIOS's behalf.
Imre Deak [Fri, 1 Apr 2016 13:02:43 +0000 (16:02 +0300)]
drm/i915/bxt: Sanitize the DBUF HW state together with CDCLK
When determining whether CDCLK is enabled by BIOS and so we should skip
reprogramming it, we didn't check the related DBUF power request and
state. In theory BIOS could enable one without the other so check for
this case and reprogram things if something is amiss.
Imre Deak [Fri, 1 Apr 2016 13:02:42 +0000 (16:02 +0300)]
drm/i915/bxt: Don't toggle power well 1 on-demand
Power well 1 is managed by the DMC firmware so don't toggle it on-demand
from the driver. This means we need to follow the BSpec display
initialization sequence during driver loading and resuming (both system
and runtime) and enable power well 1 only once there. Afterwards DMC
will toggle power well 1 whenever entering/exiting DC5.
For this to work we also need to do away getting the PLL power domain,
since that just kept runtime PM disabled for good.
Imre Deak [Fri, 1 Apr 2016 13:02:41 +0000 (16:02 +0300)]
drm/i915/bxt: Power down DDI PHYs separately during the per PHY uninit
The power-down step logically belongs to the individual PHY uninit
sequence so move it there. The only functional change is that we will
power down now PHY 1 separately before PHY 0 and preserve the other bits
in the register which are defined as reserved.
Imre Deak [Mon, 4 Apr 2016 12:42:57 +0000 (15:42 +0300)]
drm/i915/skl: Unexport skl_pw1_misc_io_init
On Broxton we need to enable/disable power well 1 during the init/unit
display sequence similarly to Skylake/Kabylake. The code for this will
be added in a follow-up patch, but to prepare for that unexport
skl_pw1_misc_io_init(). It's a simple function called only from a single
place and having it inlined in the Skylake display core init/unit
functions will make it easier to compare it with its Broxton
counterpart.
This also flips the order of Misc IO and power well 1 disabling which
matches the enabling order. The specification doesn't prescribe the
disabling order, so this should be fine.
v2:
- Fix incorrect enable vs. disable power well call in
skl_display_core_uninit() (Patrik)
- Add commit comment about chaning the order of PW1 and Misc IO power
well disabling (Patrik)
Imre Deak [Fri, 1 Apr 2016 13:02:38 +0000 (16:02 +0300)]
drm/i915/bxt: Suspend power domains during suspend-to-idle
On SKL/KBL suspend-to-idle (aka freeze/s0ix) is performed with DMC
firmware assistance where the target display power state is DC6. On
Broxton on the other hand we don't use the firmware for this, but rely
instead on a manual DC9 flow. For this we have to uninitialize the
display following the BSpec display uninit sequence, just as during
S3/S4, so make sure we follow this sequence.
Imre Deak [Fri, 1 Apr 2016 13:02:37 +0000 (16:02 +0300)]
drm/i915/gen9: Fix DMC/DC state asserts
The display power well support and DC state management doesn't depend on
runtime PM support, so remove the incorrect asserts about this.
Also Broxton does support DC5, so the related assert in
assert_can_enable_dc5() is incorrect. There is a more generic and
correct assert for this already in gen9_set_dc_state(), so we can remove
all the other ones.
At the same time convert WARNs to WARN_ONCE for consistency with the
other DC state asserts.
Imre Deak [Fri, 1 Apr 2016 13:02:36 +0000 (16:02 +0300)]
drm/i915/gen9: Make power well disabling synchronous
So far we only power well enabling was synchronous not disabling. Since
we don't exactly know how the firmware (both DMC and PCU) synchronizes
against the actual power well state during DC transitions, make the
disabling also synchronous.
Imre Deak [Tue, 5 Apr 2016 10:26:05 +0000 (13:26 +0300)]
drm/i915/gen9: Reset secondary power well requests left on by DMC/KVMR
DMC forces on power well 1 and the misc IO power well by setting the
corresponding request bits both in the BIOS and the DEBUG power well
request registers. This is somewhat unexpected since the firmware should
really just save and restore state but not alter it. We also depend on
being able to disable power well 1, and the misc IO power well before
entering S3/S4 on BXT and SKL or entering DC9 on BXT. To fix this make
sure these request bits are cleared whenever we want to disable the
given power wells.
On SKL there is another twist where the firmware also clears the power
well 1 request bit in HSW_POWER_WELL_DRIVER (but not that of the misc IO
power well). This happens to not cause a problem due to the forced-on
request bits in the other request registers.
I've filed a bug about all this, but fixing that may take a while and
having this sanity check in place makes sense even for future firmware
versions.
At the same time also check the KVMR request bits. I haven't seen this
being altered, but we don't expect any request bits in here either, so
sanitize this register as well.
v2:
- Apply the workaround on SKL as well. I noticed the related failure
from the CI report, later Patrik also reported seeing it on his
machine.
Imre Deak [Fri, 1 Apr 2016 13:02:34 +0000 (16:02 +0300)]
drm/i915/bxt: Add a note about BXT_PORT_CL1CM_DW30 being read-only
This register is read-only, so we have never actually set
OCL2_LDOFUSE_PWR_DIS in it as specified by the specification. Add a code
comment about this. I filed a specification update request to clarify
this there.
Imre Deak [Fri, 1 Apr 2016 13:02:33 +0000 (16:02 +0300)]
drm/i915/bxt: Fix GRC code register field definitions
This has been corrected in BSpec quite some time ago, but we missed it
somehow. The wrong field definitions resulted in configuring PHY0 with
an incorrect GRC value.
v2:
- Remove the FIXME comment, we left in the code exactly about this
issue. (Ville)
Imre Deak [Fri, 1 Apr 2016 13:02:32 +0000 (16:02 +0300)]
drm/i915/bxt: Reject DMC firmware versions with known bugs
DMC version 1.06 has a known bug, where the firmware polls forever for a
port PLL to lock, if the PLL was disabled when entering DC5, which locks
up the machine. Version 1.07 fixes this, so make that the minimum
required version on BXT.
Ville Syrjälä [Wed, 13 Apr 2016 18:19:56 +0000 (21:19 +0300)]
drm/i915: Move gt/pm irq handling out from irq disabled section on VLV
No need to actually handle the GT/PM interrupt while we have interrupt
sources disabled. Move the actual processing to happen after we've
restored VLV_IER and master interrupt enable.
Ville Syrjälä [Wed, 13 Apr 2016 18:19:54 +0000 (21:19 +0300)]
drm/i915: Split PORT_HOTPLUG_STAT ack out from i9xx_hpd_irq_handler()
Split the VLV/CHV hoplug irq handling to ack and handler phases. This
way we can move the actual irq handling outside the section where
we have disabled the interrupt sources.
For now, we leave things as is for pre-VLV GMCH platforms, but
eventually they could get the same treatment.
Ville Syrjälä [Wed, 13 Apr 2016 18:19:52 +0000 (21:19 +0300)]
drm/i915: Eliminate loop from VLV irq handler
Now that we've dealt with the races in clearing IIR bits via VLV_IER
and the master interrupt enable, we can go ahead aliminate the loop
from the VLV interrupt handler.
Ville Syrjälä [Wed, 13 Apr 2016 18:19:51 +0000 (21:19 +0300)]
drm/i915: Clear VLV_IER around irq processing
On VLV/CHV the master interrupt enable bit only affects GT/PM
interrupts. Display interrupts are not affected by the master
irq control.
Also it seems that the CPU interrupt will only be generated when
the combined result of all GT/PM/display interrupts has a 0->1
edge. We already use the master interrupt enable bit to make sure
GT/PM interrupt can generate such an edge if we don't end up clearing
all IIR bits. We must do the same for display interrupts, and for
that we can simply clear out VLV_IER, and restore after we've acked
all the interrupts we are about to process.
So with both master interrupt enable and VLV_IER cleared out, we will
guarantee that there will be a 0->1 edge if any IIR bits are still set
at the end, and thus another CPU interrupt will be generated.
Ville Syrjälä [Wed, 13 Apr 2016 18:19:50 +0000 (21:19 +0300)]
drm/i915: Clear VLV_MASTER_IER around irq processing
Like on CHV, let's clear out the master irq enable bit when we ack
GT/PM interrupts. This will allow GT/PM interrupts to re-raise the
CPU interrupt if we fail to clear all the bits from the IIR(s).
Ville Syrjälä [Wed, 13 Apr 2016 18:19:49 +0000 (21:19 +0300)]
drm/i915: Clear VLV_IIR after PIPESTAT
On VLV/CHV VLV_IIR is not double double buffered, and it doesn't detect
edges from PIPESTAT & co. like it does on gen4. Instead it just
directly latches the level from PIPESTAT & co. That means we must clear
VLV_IIR after PIPESTAT & co. or else we'll get a spurious bit in VLV_IIR
every single time.
Ville Syrjälä [Wed, 13 Apr 2016 18:19:48 +0000 (21:19 +0300)]
drm/i915: Set up VLV_MASTER_IER consistently
We're lacking VLV_MASTER_IER setup from valleyview_irq_preinstall(), so
add it there. Also cargo cult in some POSTING_READ()s to match the other
platforms.
Ville Syrjälä [Wed, 13 Apr 2016 18:19:47 +0000 (21:19 +0300)]
drm/i915: Use GEN8_MASTER_IRQ_CONTROL consistently
Use GEN8_MASTER_IRQ_CONTROL instead of DE_MASTER_IRQ_CONTROL or
MASTER_INTERRUPT_ENABLE with the GEN8_MASTER_IRQ register. They're
all bit 31 so there's no actual bug here, but let's be consistent
which name we use for the bit.
Ville Syrjälä [Wed, 13 Apr 2016 18:09:30 +0000 (21:09 +0300)]
drm/i915: Ignore GTFIFODBG FIFO free entry fields on CHV
On CHV GTFIFODBG has some read-only bits to indicate the number
of free FIFO entries. Ignore these when checking to see if any
of the sticky error bits are set.
This gets rid of these during device resume:
[drm:cherryview_enable_rps] GT fifo had a previous error 1080000
While at it, move the assignments out of the if().
Peter Antoine [Wed, 13 Apr 2016 14:03:25 +0000 (15:03 +0100)]
drm/i915/mocs: Program MOCS for all engines on init
Allow for the MOCS to be programmed for all engines.
Currently we program the MOCS when the first render batch
goes through. This works on most platforms but fails on
platforms that do not run a render batch early,
i.e. headless servers. The patch now programs all initialised engines
on init and the RCS is programmed again within the initial batch. This
is done for predictable consistency with regards to the hardware
context.
Hardware context loading sets the values of the MOCS for RCS
and L3CC. Programming them from within the batch makes sure that
the render context is valid, no matter what the previous state of
the saved-context was.
v2: posted correct version to the mailing list.
v3: moved programming to within engine->init_hw() (Chris Wilson)
v4: code formatting and white-space changes. (Chris Wilson)
Chris Wilson [Wed, 13 Apr 2016 16:35:15 +0000 (17:35 +0100)]
drm/i915: Late request cancellations are harmful
Conceptually, each request is a record of a hardware transaction - we
build up a list of pending commands and then either commit them to
hardware, or cancel them. However, whilst building up the list of
pending commands, we may modify state outside of the request and make
references to the pending request. If we do so and then cancel that
request, external objects then point to the deleted request leading to
both graphical and memory corruption.
The easiest example is to consider object/VMA tracking. When we mark an
object as active in a request, we store a pointer to this, the most
recent request, in the object. Then we want to free that object, we wait
for the most recent request to be idle before proceeding (otherwise the
hardware will write to pages now owned by the system, or we will attempt
to read from those pages before the hardware is finished writing). If
the request was cancelled instead, that wait completes immediately. As a
result, all requests must be committed and not cancelled if the external
state is unknown.
All that remains of i915_gem_request_cancel() users are just a couple of
extremely unlikely allocation failures, so remove the API entirely.
A consequence of committing all incomplete requests is that we generate
excess breadcrumbs and fill the ring much more often with dummy work. We
have completely undone the outstanding_last_seqno optimisation.
Chris Wilson [Wed, 13 Apr 2016 16:35:14 +0000 (17:35 +0100)]
drm/i915: Reorganise legacy context switch to cope with late failure
After mi_set_context() succeeds, we need to update the state of the
engine's last_context. This ensures that we hold a pin on the context
whilst the hardware may write to it. However, since we didn't complete
the post-switch setup of the context, we need to force the subsequent
use of the same context to complete the setup (which means updating
should_skip_switch()).
Chris Wilson [Wed, 13 Apr 2016 16:35:13 +0000 (17:35 +0100)]
drm/i915: Split out !RCS legacy context switching
Having the !RCS legacy context switch threaded through the RCS switching
code makes it much harder to follow and understand. In the next patch, I
want to fix a bug handling the incomplete switch, this is made much
simpler if we segregate the two paths now.
Chris Wilson [Wed, 13 Apr 2016 16:35:12 +0000 (17:35 +0100)]
drm/i915: Move the mb() following release-mmap into release-mmap
As paranoia, we want to ensure that the CPU's PTEs have been revoked for
the object before we return from i915_gem_release_mmap(). This allows us
to rely on there being no outstanding memory accesses from userspace
and guarantees serialisation of the code against concurrent access just
by calling i915_gem_release_mmap().
v2: Reduce the mb() into a wmb() following the revoke.
Chris Wilson [Wed, 13 Apr 2016 16:35:11 +0000 (17:35 +0100)]
drm/i915: Force ringbuffers to not be at offset 0
For reasons unknown Sandybridge GT1 (at least) will eventually hang when
it encounters a ring wraparound at offset 0. The test case that
reproduces the bug reliably forces a large number of interrupted context
switches, thereby causing very frequent ring wraparounds, but there are
similar bug reports in the wild with the same symptoms, seqno writes
stop just before the wrap and the ringbuffer at address 0. It is also
timing crucial, but adding various delays hasn't helped pinpoint where
the window lies.
Whether the fault is restricted to the ringbuffer itself or the GTT
addressing is unclear, but moving the ringbuffer fixes all the hangs I
have been able to reproduce.
Chris Wilson [Wed, 13 Apr 2016 16:35:10 +0000 (17:35 +0100)]
drm/i915: Prevent machine death on Ivybridge context switching
Two concurrent writes into the same register cacheline has the chance of
killing the machine on Ivybridge and other gen7. This includes LRI
emitted from the command parser. The MI_SET_CONTEXT itself serves as
serialising barrier and prevents the pair of register writes in the first
packet from triggering the fault. However, if a second switch-context
immediately occurs then we may have two adjacent blocks of LRI to the
same registers which may then trigger the hang. To counteract this we
need to insert a delay after the second register write using SRM.
This is easiest to reproduce with something like
igt/gem_ctx_switch/interruptible that triggers back-to-back context
switches (with no operations in between them in the command stream,
which requires the execbuf operation to be interrupted after the
MI_SET_CONTEXT) but can be observed sporadically elsewhere when running
interruptible igt. No reports from the wild though, so it must be of low
enough frequency that no one has correlated the random machine freezes
with i915.ko
The issue was introduced with
commit 2c550183476dfa25641309ae9a28d30feed14379 [v3.19]
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date: Tue Dec 16 10:02:27 2014 +0000
drm/i915: Disable PSMI sleep messages on all rings around context switches
Chris Wilson [Wed, 13 Apr 2016 16:35:09 +0000 (17:35 +0100)]
drm/i915: Suppress error message when GPU resets are disabled
If we do not have lowlevel support for reseting the GPU, or if the user
has explicitly disabled reseting the device, the failure is expected.
Since it is an expected failure, we should be using a lower priority
message than *ERROR*, perhaps NOTICE. In the absence of DRM_NOTICE, just
emit the expected failure as a DEBUG message.
Chris Wilson [Wed, 13 Apr 2016 16:35:08 +0000 (17:35 +0100)]
drm/i915: Prevent leaking of -EIO from i915_wait_request()
Reporting -EIO from i915_wait_request() has proven very troublematic
over the years, with numerous hard-to-reproduce bugs cropping up in the
corner case of where a reset occurs and the code wasn't expecting such
an error.
If the we reset the GPU or have detected a hang and wish to reset the
GPU, the request is forcibly complete and the wait broken. Currently, we
report either -EAGAIN or -EIO in order for the caller to retreat and
restart the wait (if appropriate) after dropping and then reacquiring
the struct_mutex (essential to allow the GPU reset to proceed). However,
if we take the view that the request is complete (no further work will
be done on it by the GPU because it is dead and soon to be reset), then
we can proceed with the task at hand and then drop the struct_mutex
allowing the reset to occur. This transfers the burden of checking
whether it is safe to proceed to the caller, which in all but one
instance it is safe - completely eliminating the source of all spurious
-EIO.
Of note, we only have two API entry points where we expect that
userspace can observe an EIO. First is when submitting an execbuf, if
the GPU is terminally wedged, then the operation cannot succeed and an
-EIO is reported. Secondly, existing userspace uses the throttle ioctl
to detect an already wedged GPU before starting using HW acceleration
(or to confirm that the GPU is wedged after an error condition). So if
the GPU is wedged when the user calls throttle, also report -EIO.
v2: Split more carefully the change to i915_wait_request() and assorted
ABI from the reset handling.
v3: Add a couple of WARN_ON(EIO) to the interruptible modesetting code
so that we don't start to leak EIO there in future (and break our hang
resistant modesetting).
Chris Wilson [Wed, 13 Apr 2016 16:35:07 +0000 (17:35 +0100)]
drm/i915: Simplify reset_counter handling during atomic modesetting
Now that the reset_counter is stored on the request, we can rearrange
the code to handle reading the counter versus waiting during the atomic
modesetting for readibility (by deleting the hairiest of codes).
Chris Wilson [Wed, 13 Apr 2016 16:35:06 +0000 (17:35 +0100)]
drm/i915: Store the reset counter when constructing a request
As the request is only valid during the same global reset epoch, we can
record the current reset_counter when constructing the request and reuse
it when waiting upon that request in future. This removes a very hairy
atomic check serialised by the struct_mutex at the time of waiting and
allows us to transfer those waits to a central dispatcher for all
waiters and all requests.
PS: With per-engine resets, we obviously cannot assume a global reset
epoch for the requests - a per-engine epoch makes the most sense. The
challenge then is how to handle checking in the waiter for when to break
the wait, as the fine-grained reset may also want to requeue the
request (i.e. the assumption that just because the epoch changes the
request is completed may be broken - or we just avoid breaking that
assumption with the fine-grained resets).
Chris Wilson [Wed, 13 Apr 2016 16:35:05 +0000 (17:35 +0100)]
drm/i915: Tighten reset_counter for reset status
In the reset_counter, we use two bits to track a GPU hang and reset. The
low bit is a "reset-in-progress" flag that we set to signal when we need
to break waiters in order for the recovery task to grab the mutex. As
soon as the recovery task has the mutex, we can clear that flag (which
we do by incrementing the reset_counter thereby incrementing the gobal
reset epoch). By clearing that flag when the recovery task holds the
struct_mutex, we can forgo a second flag that simply tells GEM to ignore
the "reset-in-progress" flag.
The second flag we store in the reset_counter is whether the
reset failed and we consider the GPU terminally wedged. Whilst this flag
is set, all access to the GPU (at least through GEM rather than direct mmio
access) is verboten.
PS: Fun is in store, as in the future we want to move from a global
reset epoch to a per-engine reset engine with request recovery.
Chris Wilson [Wed, 13 Apr 2016 16:35:04 +0000 (17:35 +0100)]
drm/i915: Simplify checking of GPU reset_counter in display pageflips
If we, when we store the reset_counter for the operation, we ensure that
it is not in a wedged or in the middle of a reset, we can then assert that
if any reset occurs the reset_counter must change. Later we can just
compare the operation's reset epoch against the current counter to see
if we need to abort the operation (to handle the hang).
Chris Wilson [Wed, 13 Apr 2016 16:35:03 +0000 (17:35 +0100)]
drm/i915: Hide the atomic_read(reset_counter) behind a helper
This is principally a little bit of syntatic sugar to hide the
atomic_read()s throughout the code to retrieve the current reset_counter.
It also provides the other utility functions to check the reset state on the
already read reset_counter, so that (in later patches) we can read it once
and do multiple tests rather than risk the value changing between tests.
v2: Be more strict on converting existing i915_reset_in_progress() over to
the more verbose i915_reset_in_progress_or_wedged().
Chris Wilson [Wed, 13 Apr 2016 16:35:02 +0000 (17:35 +0100)]
drm/i915: Add GEM debugging Kconfig option
Currently there is a #define to enable extra BUG_ON for debugging
requests and associated activities. I want to expand its use to cover
all of GEM internals (so that we can saturate the code with asserts).
We can add a Kconfig option to make it easier to enable - with the usual
caveats of not enabling unless explicitly requested.
Chris Wilson [Wed, 13 Apr 2016 16:35:01 +0000 (17:35 +0100)]
drm/i915: Disentangle i915_drv.h includes
Separate out the layers of includes (linux, drm, intel, i915) so that it
is a little easier to order our definitions between our multiple
reentrant headers. A couple of headers needed fixes to make them more
standalone (forgotten includes, forward declarations etc).
Chris Wilson [Wed, 13 Apr 2016 16:35:00 +0000 (17:35 +0100)]
drm/i915: Force clean compilation with -Werror
Our driver compiles clean (nowadays thanks to 0day) but for me, at least,
it would be beneficial if the compiler threw an error rather than a
warning when it found a piece of suspect code. (I use this to
compile-check patch series and want to break on the first compiler error
in order to fix the patch.)
v2: Kick off a new "Debugging" submenu for i915.ko
At this point, we applied it to the kernel and promptly kicked it out
again as it broke buildbots (due to a compiler warning on 32bits):
Revert "drm/i915: Force clean compilation with -Werror"
v3: Avoid enabling -Werror for allyesconfig/allmodconfig builds, using
COMPILE_TEST as a suitable proxy suggested by Andrew Morton. (Damien)
Only make the option available for EXPERT to reinforce that the option
should not be casually enabled.
Mika Kuoppala [Wed, 13 Apr 2016 14:26:44 +0000 (17:26 +0300)]
drm/i915: Calculate edram size
With gen9+ the edram capabilities are defined so
that we can calculate the edram (ellc) size accordingly.
Note that there are undefined combinations for some subset of
edram capability bits. Return the closest size for undefined indexes.
Even if we get it wrong with beginning of future gen enabling, the size
information is currently only used for boot message and in debugfs entry.
v2: Use function instead of hard to read macro (Daniel)
v3: s/INTEL_INFO/INTEL_GEN (Matthew)
Mika Kuoppala [Wed, 13 Apr 2016 14:26:43 +0000 (17:26 +0300)]
drm/i915: Store and use edram capabilities
Store the edram capabilities instead of only the size of
edram. This is preparatory patch to allow edram size calculation
based on edram capability bits for gen9+. With gen9 the
edram is behind llc and is a separate entity. With hsw/bdw
it was more of a victim cache for LLC so the name 'eLLC' might
be warranted. Regardless, rename all mentions of eLLC to EDRAM to
clear the confusion.
v2: return bytes for edram size (Chris)
s/eLLC/eDRAM in output if we are gen > 8
v3: rebase, INTEL_GEN (Chris)
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Michał Winiarski [Tue, 12 Apr 2016 13:51:55 +0000 (15:51 +0200)]
drm/i915: Adjust size of PIPE_CONTROL used for gen8 render seqno write
We started to use PIPE_CONTROL to write render ring seqno in order to
combat seqno write vs interrupt generation problems. This was introduced
by commit 7c17d377374d ("drm/i915: Use ordered seqno write interrupt
generation on gen8+ execlists").
On gen8+ size of PIPE_CONTROL with Post Sync Operation should be
6 dwords. When we're using older 5-dword variant it's possible to
observe inconsistent values written by PIPE_CONTROL with Post
Sync Operation from user batches, resulting in rendering corruptions.
v2: Fix BAT failures
v3: Comments on alignment and thrashing high dword of seqno (Chris)
v4: Updated commit msg (Mika)
Testcase: igt/gem_pipe_control_store_loop/*-qword-write
Issue: VIZ-7393 Cc: stable@vger.kernel.org Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Mika Kuoppala <mika.kuoppala@intel.com> Cc: Abdiel Janulgue <abdiel.janulgue@linux.intel.com> Signed-off-by: Michał Winiarski <michal.winiarski@intel.com> Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Tested-by: Abdiel Janulgue <abdiel.janulgue@linux.intel.com> Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/1460469115-26002-1-git-send-email-michal.winiarski@intel.com
Mika Kuoppala [Tue, 5 Apr 2016 12:56:17 +0000 (15:56 +0300)]
drm/i915/skl: Fix spurious gpu hang with gt3/gt4 revs
Experiments with heaven 4.0 benchmark and skylake gt3e (rev 0xa)
suggest that WaForceContextSaveRestoreNonCoherent is needed for all
revs. Extending this to all revs cures a gpu hang with rev 0xa when
running heaven4.0 gpu benchmark.
We have been here before, with problems enabling gt4e and extending
up to revision F0 instead of false claims of bspec of E0 only. See
commit <e238659ddd88> ("drm/i915/skl: Default to noncoherent access
up to F0"). In retrospect we should have covered this with this big
blanket back then already, as E0 vs F0 discrepancy was suspicious
enough.
Previously the WaForceEnableNonCoherent has been tied to
context non-coherence, atleast in relevant hsds. So keep this tie
and extended this alongside.
Cc: Abdiel Janulgue <abdiel.janulgue@linux.intel.com> Cc: Ben Widawsky <benjamin.widawsky@intel.com> Cc: Timo Aaltonen <tjaalton@ubuntu.com> Cc: stable@vger.kernel.org Reported-by: Mike Lothian <mike@fireburn.co.uk>
References: https://bugs.freedesktop.org/show_bug.cgi?id=93491 Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com> Reviewed-by: Ben Widawsky <benjamin.widawsky@intel.com> Tested-by: Timo Aaltonen <tjaalton@ubuntu.com> Link: http://patchwork.freedesktop.org/patch/msgid/1459860977-27751-2-git-send-email-mika.kuoppala@intel.com
Mika Kuoppala [Tue, 5 Apr 2016 12:56:16 +0000 (15:56 +0300)]
drm/i915/skl: Fix rc6 based gpu/system hang
For all gt3 and gt4 skylake variants, extend the usage of
WaRsDisableCoarsePowerGating for all revisions. Without this
gt3 and gt4 skylakes up to atleast rev 0xa can gpu hang or
system hang.
Cc: Abdiel Janulgue <abdiel.janulgue@linux.intel.com> Cc: Ben Widawsky <benjamin.widawsky@intel.com> Cc: Timo Aaltonen <tjaalton@ubuntu.com> Cc: <stable@vger.kernel.org> Reported-by: Mikael Djurfeldt <mikael@djurfeldt.com>
References: https://bugs.freedesktop.org/show_bug.cgi?id=94161 Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com> Reviewed-by: Ben Widawsky <benjamin.widawsky@intel.com> Tested-by: Timo Aaltonen <tjaalton@ubuntu.com> Link: http://patchwork.freedesktop.org/patch/msgid/1459860977-27751-1-git-send-email-mika.kuoppala@intel.com
We can use the new pin/lazy unpin API for simplicity
and more performance in the execlist submission paths.
v2:
* Fix error handling and convert more users.
* Compact some names for readability.
v3:
* intel_lr_context_free was not unpinning.
* Special case for GPU reset which otherwise unbalances
the HWS object pages pin count by running the engine
initialization only (not destructors).
drm/i915: Split execlists hardware status page initialisation from setup
Split the hardware status page into setup and initialisation,
where setup means setting up the driver state to support the
engine, and initialization means programming the hardware
with the before set up state.
This way the design matches the design of the engine setup/init
code which is split in the same fashion and it enables the
stages to be used in a balanced fashion (engine setup - hws
setup, engine init - hws init).
This will enable the upcoming improvements to slot in without
any kludges on the GPU reset path.
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Suggested-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Ville Syrjälä [Tue, 15 Mar 2016 14:40:03 +0000 (16:40 +0200)]
drm/i915: Power down the DSI PLL before reconfiguring it
On VLV at least, the BIOS may leave the DSI PLL enabled in some wonky
state where it just refuses to lock. Simply disabling the PLL before
reconfiguring it is not enough to fix it, but power gating the PLL
prior to reconfiguring does work.
This happens on BYT FFRD8 when booting with HDMI connected so the DSI
display will not be lit up by the BIOS.
Also we can remove the code for BXT that disables the PLL before
enabling it again.
v2: s/vlv/intel/ since BXT made thing generic
v3: Remove the BXT disable PLL before enable trick
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