Equivalent to the existing for_each_engine() macro, this will replace
the latter wherever the third argument *is* actually wanted (in most
places, it is not used). The third argument is renamed to emphasise
that it is an engine id (type enum intel_engine_id). All the callers of
the macro that actually need the third argument are updated to use this
version, and the argument (generally 'i') is also updated to be 'id'.
Other callers (where the third argument is unused) are untouched for
now; they will be updated in the next patch.
Signed-off-by: Dave Gordon <david.s.gordon@intel.com>
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Some trivial ones, first pass done with Coccinelle:
@@
@@
(
- I915_NUM_RINGS
+ I915_NUM_ENGINES
|
- intel_ring_flag
+ intel_engine_flag
|
- for_each_ring
+ for_each_engine
|
- i915_gem_request_get_ring
+ i915_gem_request_get_engine
|
- intel_ring_idle
+ intel_engine_idle
|
- i915_gem_reset_ring_status
+ i915_gem_reset_engine_status
|
- i915_gem_reset_ring_cleanup
+ i915_gem_reset_engine_cleanup
|
- init_ring_lists
+ init_engine_lists
)
But that didn't fully work so I cleaned it up with:
for f in *.[hc]; do sed -i -e s/I915_NUM_RINGS/I915_NUM_ENGINES/ $f; done
for f in *.[hc]; do sed -i -e s/i915_gem_request_get_ring/i915_gem_request_get_engine/ $f; done
for f in *.[hc]; do sed -i -e s/intel_ring_flag/intel_engine_flag/ $f; done
for f in *.[hc]; do sed -i -e s/intel_ring_idle/intel_engine_idle/ $f; done
for f in *.[hc]; do sed -i -e s/init_ring_lists/init_engine_lists/ $f; done
for f in *.[hc]; do sed -i -e s/i915_gem_reset_ring_cleanup/i915_gem_reset_engine_cleanup/ $f; done
for f in *.[hc]; do sed -i -e s/i915_gem_reset_ring_status/i915_gem_reset_engine_status/ $f; done
v2: Rebase.
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
With full-ppgtt, it takes the GPU an eon to traverse the entire 256PiB
address space, causing a loop to be detected. Under the current scheme,
if ACTHD walks off the end of a batch buffer and into an empty
address space, we "never" detect the hang. If we always increment the
score as the ACTHD is progressing then we will eventually timeout (after
~46.5s (31 * 1.5s) without advancing onto a new batch). To counter act
this, increase the amount we reduce the score for good batches, so that
only a series of almost-bad batches trigger a full reset. DoS detection
suffers slightly but series of long running shader tests will benefit.
Based on a patch from Chris Wilson.
Testcase: igt/drv_hangman/hangcheck-unterminated
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/1456930109-21532-1-git-send-email-mika.kuoppala@intel.com
We have done unclaimed register access check in normal
(mmio_debug=0) mode once per write. This adds probability
of finding the exact sequence where we did the bad access, but
also adds burden to each write.
As we have mmio_debug available for more fine grained analysis,
give up accuracy of detecting correct spot at the first occurrence
by doing the one shot detection and arming of mmio_debug in hangcheck
and in modeset. This removes the write path performance burden.
v2: Remove gratuitous DRM_DEBUG and return value, comments (Chris)
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Paulo Zanoni <przanoni@gmail.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1450250808-14864-1-git-send-email-mika.kuoppala@intel.com
Currently interrupt code is the only place checking
for the unclaimed register access prior to actual register
macros using the same functionality. Rename the function
and make it return bool so that the possible error message
context is clear in the caller side. The motivation is to allow
usage of unclaimed detection on arbitrary places.
v2: rebase, s/access/mmio, s/dev/dev_priv
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1450189512-30360-2-git-send-email-mika.kuoppala@intel.com
If head seems stuck and engine in question is rcs,
inspect subunit state transitions from undone to done,
before deciding that this really is a hang instead of limited
progress. Only account the transitions of subunits from
undone to done once, to prevent unstable subunit states
to keep us falsely active.
As this adds one extra steps to hangcheck heuristics,
before hang is declared, it adds 1500ms to to detect hang
for render ring to a total of 7500ms. We could sample
the subunit states on first head stuck condition but
decide not to do so only in order to mimic old behaviour. This
way the check order of promotion from seqno > atchd > instdone
is consistently done.
v2: Deal with unstable done states (Arun)
Clear instdone progress on head and seqno movement (Chris)
Report raw and accumulated instdone's in in debugfs (Chris)
Return HANGCHECK_ACTIVE on undone->done
References: https://bugs.freedesktop.org/show_bug.cgi?id=93029
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Dave Gordon <david.s.gordon@intel.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Arun Siluvery <arun.siluvery@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1448985372-19535-1-git-send-email-mika.kuoppala@intel.com
Atm, we assert that the device is not suspended until the point when the
device is truly put to a suspended state. This is fine, but we can catch
more problems if we check that RPM refcount is non-zero. After that one
drops to zero we shouldn't access the device any more, even if the actual
device suspend may be delayed. Change assert_rpm_wakelock_held()
accordingly to check for a non-zero RPM refcount in addition to the
current device-not-suspended check.
For the new asserts to work we need to annotate every place explicitly in
the code where we expect that the device is powered. The places where we
only assume this, but may not hold an RPM reference:
- driver load
We assume the device to be powered until we enable RPM. Make this
explicit by taking an RPM reference around the load function.
- system and runtime sudpend/resume handlers
These handlers are called when the RPM reference becomes 0 and know the
exact point after which the device can get powered off. Disable the
RPM-reference-held check for their duration.
- the IRQ, hangcheck and RPS work handlers
These handlers are flushed in the system/runtime suspend handler
before the device is powered off, so it's guaranteed that they won't
run while the device is powered off even though they don't hold any
RPM reference. Disable the RPM-reference-held check for their duration.
In all these cases we still check that the device is not suspended.
These explicit annotations also have the positive side effect of
documenting our assumptions better.
This caught additional WARNs from the atomic modeset path, those should
be fixed separately.
v2:
- remove the redundant HAS_RUNTIME_PM check (moved to patch 1) (Ville)
v3:
- use a new dedicated RPM wakelock refcount to also catch cases where
our own RPM get/put functions were not called (Chris)
- assert also that the new RPM wakelock refcount is 0 in the RPM
suspend handler (Chris)
- change the assert error message to be more meaningful (Chris)
- prevent false assert errors and check that the RPM wakelock is 0 in
the RPM resume handler too
- prevent false assert errors in the hangcheck work too
- add a device not suspended assert check to the hangcheck work
v4:
- rename disable/enable_rpm_asserts to disable/enable_rpm_wakeref_asserts
and wakelock_count to wakeref_count
- disable the wakeref asserts in the IRQ handlers and RPS work too
- update/clarify commit message
v5:
- mark places we plan to change to use proper RPM refcounting with
separate DISABLE/ENABLE_RPM_WAKEREF_ASSERTS aliases (Chris)
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/1450227139-13471-1-git-send-email-imre.deak@intel.com
The cherryview device shares many characteristics with the valleyview
device. When support was added to the driver for cherryview, the
corresponding device info structure included .is_valleyview = 1.
This is not correct and leads to some confusion.
This patch changes .is_valleyview to .is_cherryview in the cherryview
device info structure and simplifies the IS_CHERRYVIEW macro.
Then where appropriate, instances of IS_VALLEYVIEW are replaced with
IS_VALLEYVIEW || IS_CHERRYVIEW or equivalent.
v2: Use IS_VALLEYVIEW || IS_CHERRYVIEW instead of defining a new macro.
Also add followup patches to fix issues discovered during the first
review. (Ville)
v3: Fix some style issues and one gen check. Remove CRT related changes
as CRT is not supported on CHV. (Imre, Ville)
v4: Make a few more optimizations. (Ville)
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Wayne Boyer <wayne.boyer@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1449692975-14803-1-git-send-email-wayne.boyer@intel.com
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Acked-by: Jani Nikula <jani.nikula@intel.com>
We had the "The master control interrupt lied (SDE)!" check and error
message in place for a long time without any problems, until
commit aaf5ec2e51
Author: Sonika Jindal <sonika.jindal@intel.com>
Date: Wed Jul 8 17:07:47 2015 +0530
drm/i915: Handle HPD when it has actually occurred
caused the errors to start happening. This was bisected and reported,
but the error message was silenced in
commit 97e5ed1111
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date: Fri Oct 23 10:56:12 2015 +0200
drm/i915: shut up gen8+ SDE irq dmesg noise
shooting the messenger while the debugging for why Sonika's commit
triggered the errors was still in progress.
It looks like we need to read and acknowledge the PCH_PORT_HOTPLUG
register even though the hotplug trigger indicates there isn't a hotplug
irq to handle. The PCH doesn't seem to really ack the the interrupt to
the CPU unless we touch the hotplug register.
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Sonika Jindal <sonika.jindal@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=92084
Fixes: aaf5ec2e51 ("drm/i915: Handle HPD when it has actually occurred")
[Jani: added a comment and amended the commit message while applying]
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1448462843-32739-1-git-send-email-jani.nikula@intel.com
Linux 4.4-rc2
Backmerge to get at
commit 1b0e3a049e
Author: Imre Deak <imre.deak@intel.com>
Date: Thu Nov 5 23:04:11 2015 +0200
drm/i915/skl: disable display side power well support for now
so that we can proplery re-eanble skl power wells in -next.
Conflicts are just adjacent lines changed, except for intel_fbdev.c
where we need to interleave the changs. Nothing nefarious.
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Make I915_READ and I915_WRITE more type safe by wrapping the register
offset in a struct. This should eliminate most of the fumbles we've had
with misplaced parens.
This only takes care of normal mmio registers. We could extend the idea
to other register types and define each with its own struct. That way
you wouldn't be able to accidentally pass the wrong thing to a specific
register access function.
The gpio_reg setup is probably the ugliest thing left. But I figure I'd
just leave it for now, and wait for some divine inspiration to strike
before making it nice.
As for the generated code, it's actually a bit better sometimes. Eg.
looking at i915_irq_handler(), we can see the following change:
lea 0x70024(%rdx,%rax,1),%r9d
mov $0x1,%edx
- movslq %r9d,%r9
- mov %r9,%rsi
- mov %r9,-0x58(%rbp)
- callq *0xd8(%rbx)
+ mov %r9d,%esi
+ mov %r9d,-0x48(%rbp)
callq *0xd8(%rbx)
So previously gcc thought the register offset might be signed and
decided to sign extend it, just in case. The rest appears to be
mostly just minor shuffling of instructions.
v2: i915_mmio_reg_{offset,equal,valid}() helpers added
s/_REG/_MMIO/ in the register defines
mo more switch statements left to worry about
ring_emit stuff got sorted in a prep patch
cmd parser, lrc context and w/a batch buildup also in prep patch
vgpu stuff cleaned up and moved to a prep patch
all other unrelated changes split out
v3: Rebased due to BXT DSI/BLC, MOCS, etc.
v4: Rebased due to churn, s/i915_mmio_reg_t/i915_reg_t/
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/1447853606-2751-1-git-send-email-ville.syrjala@linux.intel.com
Here's a handful of i915 fixes for drm-next/v4.4. Imre's commit alone
should address the remaining warnings galore you experienced on
Skylake. Almost all of the rest are also fixes against user or QA
reported bugs, with references.
* tag 'drm-intel-next-fixes-2015-11-06' of git://anongit.freedesktop.org/drm-intel:
drm/i915/skl: disable display side power well support for now
drm/i915: Extend DSL readout fix to BDW and SKL.
drm/i915: Do graphics device reset under forcewake
drm/i915: Skip fence installation for objects with rotated views (v4)
drm/i915: add quirk to enable backlight on Dell Chromebook 11 (2015)
drm/i915/skl: Prevent unclaimed register writes on skylake.
drm/i915: disable CPU PWM also on LPT/SPT backlight disable
drm/i915: Fix maxfifo watermark calc on vlv cursor planes
drm/i915: add hotplug activation period to hotplug update mask
Bunch of -fixes for 4.4. Well not just, I've left the mmio/register work
from Ville in here since it's low-risk but lots of churn all over.
* tag 'drm-intel-next-fixes-2015-10-22' of git://anongit.freedesktop.org/drm-intel: (23 commits)
drm/i915: Use round to closest when computing the CEA 1.001 pixel clocks
drm/i915: Kill the leftover RMW from ivb_sprite_disable()
drm/i915: restore ggtt double-bind avoidance
drm/i915/skl: Enable pipe gamma for sprite planes.
drm/i915/skl+: Enable pipe CSC on cursor planes. (v2)
MAINTAINERS: add link to the Intel Graphics for Linux web site
drm/i915: Move skl/bxt gt specific workarounds to ring init
drm/i915: Drop i915_gem_obj_is_pinned() from set-cache-level
drm/i915: revert a few more watermark commits
drm/i915: Remove dev_priv argument from NEEDS_FORCE_WAKE
drm/i915: Clean up LVDS register handling
drm/i915: Throw out some useless variables
drm/i915: Parametrize and fix SWF registers
drm/i915: s/PIPE_FRMCOUNT_GM45/PIPE_FRMCOUNT_G4X/ etc.
drm/i915: Turn GEN5_ASSERT_IIR_IS_ZERO() into a function
drm/i915: Fix a few bad hex numbers in register defines
drm/i915: Protect register macro arguments
drm/i915: Include gpio_mmio_base in GMBUS reg defines
drm/i915: Parametrize HSW video DIP data registers
drm/i915: Eliminate weird parameter inversion from BXT PPS registers
...
There's no need for __raw_i915_read8() & co. to be macros, so make them
inline functions. To avoid typo mistakes generate the inline functions
using preprocessor templates.
We have a few users of the raw register acces functions outside
intel_uncore.c, so let's also move the functions into intel_drv.h.
While doing that switch I915_READ_FW() & co. to use the
__raw_i915_read() functions, and use the _FW macros everywhere
outside intel_uncore.c where we want to read registers without
grabbing forcewake and whatnot. The only exception is
i915_check_vgpu() which itself gets called from intel_uncore.c,
so using the __raw_i915_read stuff there seems appropriate.
v2: Squash in the intel_uncore.c->i915_drv.h move
Convert I915_READ_FW() to use __raw_i915_read(), and use
I915_READ_FW() outside of intel_uncore.c (Chris)
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1445517300-28173-2-git-send-email-ville.syrjala@linux.intel.com
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
- dmc fixes from Animesh (not yet all) for deeper sleep states
- piles of prep patches from Ville to make mmio functions type-safe
- more fbc work from Paulo all over
- w/a shuffling from Arun Siluvery
- first part of atomic watermark updates from Matt and Ville (later parts had to
be dropped again unfortunately)
- lots of patches to prepare bxt dsi support ( Shashank Sharma)
- userptr fixes from Chris
- audio rate interface between i915/snd_hda plus kerneldoc (Libin Yang)
- shrinker improvements and fixes (Chris Wilson)
- lots and lots of small patches all over
* tag 'drm-intel-next-2015-10-10' of git://anongit.freedesktop.org/drm-intel: (134 commits)
drm/i915: Update DRIVER_DATE to 20151010
drm/i915: Partial revert of atomic watermark series
drm/i915: Early exit from semaphore_waits_for for execlist mode.
drm/i915: Remove wrong warning from i915_gem_context_clean
drm/i915: Determine the stolen memory base address on gen2
drm/i915: fix FBC buffer size checks
drm/i915: fix CFB size calculation
drm/i915: remove pre-atomic check from SKL update_primary_plane
drm/i915: don't allocate fbcon from stolen memory if it's too big
Revert "drm/i915: Call encoder hotplug for init and resume cases"
Revert "drm/i915: Add hot_plug hook for hdmi encoder"
drm/i915: use error path
drm/i915/irq: Fix misspelled word register in kernel-doc
drm/i915/irq: Fix kernel-doc warnings
drm/i915: Hook up ring workaround writes at context creation time on Gen6-7.
drm/i915: Don't warn if the workaround list is empty.
drm/i915: Resurrect golden context on gen6/7
drm/i915/chv: remove pre-production hardware workarounds
drm/i915/snb: remove pre-production hardware workaround
drm/i915/bxt: Set time interval unit to 0.833us
...
Another round of drm-misc. Unfortunately the DRM_UNLOCKED removal for
DRIVER_MODESET isn't complete yet for lack of review on 1-2 patches.
Otherwise just various stuff all over.
* tag 'topic/drm-misc-2015-10-08' of git://anongit.freedesktop.org/drm-intel:
drm: Stop using drm_vblank_count() as the hw frame counter
drm/irq: Use unsigned int pipe in public API
drm: Use DRM_ROTATE_MASK and DRM_REFLECT_MASK
drm: Add DRM_ROTATE_MASK and DRM_REFLECT_MASK
vga_switcheroo: Add missing locking
vgaarb: use kzalloc in vga_arbiter_add_pci_device()
drm: Don't zero vblank timestamps from the irq handler
drm: Hack around CONFIG_AGP=m build failures
drm/i915: Remove setparam ioctl
drm: Remove dummy agp ioctl wrappers
drm/vmwgfx: Stop checking for DRM_UNLOCKED
drm/drm_ioctl.c: kerneldoc
drm: Define a drm_invalid_op ioctl implementation
drm: Remove __OS_HAS_AGP
drm/doc: Update docs about device instance setup
The PIPE_FRMCOUNT_GM45 and PIPE_FLIPCOUNT_GM45 names have bothered me
for a long time. The work equally well for ELK and onwards, so let's
s/GM45/G4X/.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
When submitting semaphores in execlist mode the hang checker crashes in this
function because it is only runnable in ring submission mode. The reason this
is of particular interest to the TDR patch series is because we use semaphores
as a mean to induce hangs during testing (which is the recommended way to
induce hangs for gen8+). It's not clear how this is supposed to work in
execlist mode since:
1. This function requires a ring buffer.
2. Retrieving a ring buffer in execlist mode requires us to retrieve the
corresponding context, which we get from a request.
3. Retieving a request from the hang checker is not straight-forward since that
requires us to grab the struct_mutex in order to synchronize against the
request retirement thread.
4. Grabbing the struct_mutex from the hang checker is nothing that we will do
since that puts us at risk of deadlock since a hung thread might be holding the
struct_mutex already.
Therefore it's not obvious how we're supposed to deal with this. For now, we're
doing an early exit from this function, which avoids any kernel panic situation
when running our own internal TDR ULT.
* v2: (Chris Wilson)
Turned the execlist mode check into a ringbuffer NULL check to make it more
submission mode agnostic and less of a layering violation.
Signed-off-by: Tomas Elf <tomas.elf@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
There is a typo in the function i915_handle_error()
kernel-doc and the word register is spelled wrongly.
Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Add the dev parameter for the functions i915_enable_asle_pipestat() and
i915_reset_and_wakeup() to the kernel-doc to fix the following warnings:
.//drivers/gpu/drm/i915/i915_irq.c:586: warning: No description found for parameter 'dev'
.//drivers/gpu/drm/i915/i915_irq.c:2400: warning: No description found for parameter 'dev'
Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Replace the use of mem_freq/4 with czclk_freq in the vlv c0 residency
calculations.
Also deal with VLV_COUNT_RANGE_HIGH which affects all RCx residency
counters. We have just enough bits to do this without intermediate
divisions.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Backmerge to catch up with 4.3. slightly more involved conflict in the
irq code, but nothing beyond adjacent changes.
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Another attempt at drm-misc for 4.4 ...
- better atomic helpers for runtime pm drivers
- atomic fbdev
- dp aux i2c STATUS_UPDATE handling (for short i2c replies from the sink)
- bunch of constify patches
- inital kerneldoc for vga switcheroo
- some vblank code cleanups from Ville and Thierry
- various polish all over
* tag 'topic/drm-misc-2015-09-25' of git://anongit.freedesktop.org/drm-intel: (57 commits)
drm/irq: Add drm_crtc_vblank_count_and_time()
drm/irq: Rename drm_crtc -> crtc
drm: drm_atomic_crtc_get_property should be static
drm/gma500: Remove DP_LINK_STATUS_SIZE redefinition
vga_switcheroo: Set active attribute to false for audio clients
drm/core: Preserve the fb id on close.
drm/core: Preserve the framebuffer after removing it.
drm: Use vblank timestamps to guesstimate how many vblanks were missed
drm: store_vblank() is never called with NULL timestamp
drm: Clean up drm_calc_vbltimestamp_from_scanoutpos() vbl_status
drm: Limit the number of .get_vblank_counter() retries
drm: Pass flags to drm_update_vblank_count()
drm/i915: Fix vblank count variable types
drm: Kill pixeldur_ns
drm: Stop using linedur_ns and pixeldur_ns for vblank timestamps
drm: Move timestamping constants into drm_vblank_crtc
drm/fbdev: Update legacy plane->fb refcounting for atomic restore
drm: fix kernel-doc warnings in drm_crtc.h
vga_switcheroo: Sort headers alphabetically
drm: Spell vga_switcheroo consistently
...
linedur_ns, and especially pixeldur_ns are becoming rather inaccurate
to be used for the vblank timestamp correction. With 4k@60 the pixel
duration is already below 2ns, so the amount of error due to the
truncation to nanoseconds is introducing quite a bit of error.
We can avoid such problems if we instead calculate the timestamp
delta_ns directly from the dislay timings, avoiding the use of
these intermediate truncated values.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
[danvet: Squash in fixup from Thierry Reding for amdgpu.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
