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
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: David Weinehall <david.weinehall@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1459780030-15781-1-git-send-email-imre.deak@intel.com
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.
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1459515767-29228-12-git-send-email-imre.deak@intel.com
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.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=93907
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: stable@vger.kernel.org
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1460565315-7748-16-git-send-email-chris@chris-wilson.co.uk
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).
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1460565315-7748-9-git-send-email-chris@chris-wilson.co.uk
Link: http://patchwork.freedesktop.org/patch/msgid/1460565315-7748-1-git-send-email-chris@chris-wilson.co.uk
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).
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1460565315-7748-7-git-send-email-chris@chris-wilson.co.uk
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().
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1460565315-7748-4-git-send-email-chris@chris-wilson.co.uk
Take a bigger hammer to the underrun suppression on ILK. Instead of
trying to suppress them at specific points in the modeset sequence just
silence them across the entire sequence. This gets rid of some underruns
at least on my ILK. Note that this changes SNB and IVB to follow the
same approach just to keep the code less convoluted. The difference is
that on those platforms we won't suppress CPU underruns for port A since
it doesn't seem to be necessary.
My ILK has port A eDP and two PCH HDMI ports, so I can't be sure this is
as effective on other PCH port types. Perhaps we still need some of
Daniel's extra vblank waits [2]?
I've still been able to trigger an underrun on the other pipe, but
fixing that perhaps needs the LP1+ disable trick I implemented here [1]
which never got merged.
A few details which hamper stress testing on my ILK are that sometimes
the PCH transcoder gets messed up and refuses to shut down, and sometimes
even the panel power sequencer apparently gets stuck on the always on
position.
[1] https://lists.freedesktop.org/archives/intel-gfx/2014-March/041317.html
[2] https://lists.freedesktop.org/archives/intel-gfx/2016-January/086397.html
v2: Add a note that we also get underruns when enabling PCH ports
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> (v1)
Link: http://patchwork.freedesktop.org/patch/msgid/1459536799-18109-2-git-send-email-ville.syrjala@linux.intel.com
Reviewed-by: Patrik Jakobsson <patrik.jakobsson@linux.intel.com>
Extract the GPLL reference frequency from CCK and use it in the
GPU freq<->opcode conversions on VLV/CHV. This eliminates all the
assumptions we have about which divider is used for which czclk
frequency.
Note that unlike most clocks from CCK, the GPLL ref clock is a divided
down version of the CZ clock rather than the HPLL clock. CZ clock itself
is a divided down version of the HPLL clock though, so in effect it just
gets divided down twice.
While at it, throw in a few comments explaining the remaining constants
for anyone who later wants to compare this to the spreadsheets.
v2: Add slow/fast notes for CHV clocks (Imre)
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1457120584-26080-2-git-send-email-ville.syrjala@linux.intel.com
Reviewed-by: Imre Deak <imre.deak@intel.com> (v1)
DPLL_MD(PIPE_C) is AWOL on CHV. Instead of fixing it someone added
chicken bits to propagate the pixel multiplier from DPLL_MD(PIPE_B)
to either pipe B or C. So do that to make pixel repeat work on pipes
B and C. Pipe A is fine without any tricks.
Fortunately the pixel repeat propagation appears to be a oneshot
operation, so once the value has been written we can clear the
chicken bits. So it is still possible to drive pipe B and C with
different pixel multipliers simultaneosly.
Looks like DPLL_VGA_MODE_DIS must also be set in DPLL(PIPE_B)
for this to work. But since we keep that bit always set in all
DPLLs there's no problem.
This of course means we can't reliably read out the pixel multiplier
for pipes B and C. That would make the state checker unhappy, so I
added shadow copies of those registers in to dev_priv. The other
option would have been to skip pixel multiplier, dpll_md an dotclock
checks entirely on CHV, but that feels like a serious loss of cross
checking, so just pretending that we have working DPLL MD registers
seemed better. Obviously with the shadow copies we can't detect if
the pixel multiplier was properly configured, nor can we take over
its state from the BIOS, but hopefully people won't have displays
that would be limitd to such crappy modes.
There is one strange flicker still remaining. It's visible on
pipe C/HDMID when HDMIB is enabled while driven by pipe B.
It doesn't occur if pipe A drives HDMIB, nor is there any glitch
on pipe B/HDMIB when port C/HDMID starts up. I don't have a board
with HDMIC so not sure if it happens there too. So I'm not sure
if it's somehow tied in with this strange linkage between pipe B
and C. Sadly I was unable to find an enable sequence that would
avoid the glitch, but at least it's not fatal ie. the output
recovers afterwards.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1458052809-23426-4-git-send-email-ville.syrjala@linux.intel.com
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
The VLV and CHV DPLL disable and update are almost identical in
how the DPLL/DPLL_MD registers need to be set up. But the code
looks more different than it really is. Try to bring them into
line.
Note that we now leave the refclock always enabled for both
DPLLs in the dual channel PHY. But that's perfectly fine since
it's the same clock, and we anyway already do that when turning
the disp2d power well on.
v2: s/chv_update_pll/chv_compute_dpll/
v3: Add a note that we leave refclocks enabled for both DPLLs (Jani)
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1458052809-23426-3-git-send-email-ville.syrjala@linux.intel.com
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Refer to the GGTT VM consistently as "ggtt->base" instead of just "ggtt",
"vm" or indirectly through other variables like "dev_priv->ggtt.base"
to avoid confusion with the i915_ggtt object itself and PPGTT VMs.
Refer to the GGTT as "ggtt" instead of indirectly through chaining.
As a bonus gets rid of the long-standing i915_obj_to_ggtt vs.
i915_gem_obj_to_ggtt conflict, due to removal of i915_obj_to_ggtt!
v2:
- Added some more after grepping sources with Chris
v3:
- Refer to GGTT VM through ggtt->base consistently instead of ggtt_vm
(Chris)
v4:
- Convert all dev_priv->ggtt->foo accesses to ggtt->foo.
v5:
- Make patch checker happy
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Currently the machine hangs during booting while accessing the
BXT_MIPI_PORT_CTRL register during pipe HW state readout. After some
experimentation I found that the hang is caused by the DSI PLL being
disabled, or it being enabled but with an incorrect divider
configuration. Enabling the PLL got rid of the boot problem, so fix
this by checking the PLL enabled state/configuration before attempting
to read out the HW state.
The DSI_PLL_ENABLE register is in the always-on power well, while the
BXT_DSI_PLL_CTL is in power well 0. This isn't exactly matched by the
transcoder power domain, but what we really need is just a runtime PM
reference, which is provided by any power domain.
Ville also found this dependency specified in BSpec, so I added a
reference to that too.
v2:
- Make sure we hold a power reference while accessing the PLL registers.
v3: (Jani)
- Simplify check in bxt_get_dsi_transcoder_state()
- Add comment explaining why we check for valid dividers in
bxt_dsi_pll_is_enabled()
CC: Shashank Sharma <shashank.sharma@intel.com>
CC: Uma Shankar <uma.shankar@intel.com>
CC: Jani Nikula <jani.nikula@intel.com>
Fixes: c6c794a2fc ("drm/i915/bxt: Initialize MIPI DSI for BXT")
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Shashank Sharma <shashank.sharma@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1458816100-31269-1-git-send-email-imre.deak@intel.com
In order for VLV and CHV to use i9xx_crtc_compute_clocks(), a number
of if ladders is necessary: one for setting the find_dpll() hook, one
for choosing the limits struct, one for choosing the right compute dpll
function and one for initializing the crtc_compute_clock() hook.
By extracting a platform specific implementation for each platform, the
number of if-ladders is reduced to one.
While at it also clean up bxt_find_best_dpll() which depends on some of
the CHV code.
Signed-off-by: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1458576016-30348-13-git-send-email-ander.conselvan.de.oliveira@intel.com