In
commit def35e7c59
Author: Shayenne Moura <shayenneluzmoura@gmail.com>
Date: Wed Jan 30 14:06:36 2019 -0200
drm/vkms: Bugfix extra vblank frame
we fixed the vblank counter to give accurate results outside of
drm_crtc_handle_vblank, which fixed bugs around vblank timestamps
being off-by-one and causing the vblank counter to jump when it
shouldn't.
The trouble is that this completely broke crc generation. Shayenne and
Rodrigo tracked this down to the vblank timestamp going backwards in
time somehow. Which then resulted in an underflow in drm_vblank.c
code, which resulted in all kinds of things breaking really badly.
The reason for this is that once we've called drm_crtc_handle_vblank
and the hrtimer isn't forwarded yet, we're returning a vblank
timestamp in the past. This race is really hard to hit since it's
small, except when you enable crc generation: In that case there's a
call to drm_crtc_accurate_vblank right in-betwen, so we're guaranteed
to hit the bug.
The fix is to roll the hrtimer forward _before_ we do the vblank
processing (which has a side-effect of incrementing the vblank
counter), and we always subtract one frame from the hrtimer - since
now it's always one frame in the future.
To make sure we don't hit this again also add a WARN_ON checking for
whether our timestamp is somehow moving into the past, which is never
should.
This also aligns more with how real hw works:
1. first all registers are updated with the new timestamp/vblank
counter values.
2. then an interrupt is generated
3. kernel interrupt handler eventually fires.
So doing this aligns vkms closer with what drm_vblank.c expects.
Document this also in a comment.
Cc: Shayenne Moura <shayenneluzmoura@gmail.com>
Cc: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Tested-by: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com>
Reviewed-by: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com>
Signed-off-by: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190606084404.12014-1-daniel.vetter@ffwll.ch
The function vkms_output_init() is invoked during the module
initialization, and it handles the creation/configuration of the vkms
essential elements (e.g., connectors, encoder, etc). Among the
initializations, this function tries to initialize a connector and
register it by calling drm_connector_register(). However, inside the
drm_connector_register(), at the beginning of this function there is the
following validation:
if (!connector->dev->registered)
return 0;
In this sense, invoke drm_connector_register() after initializing the
connector has no effect because the register field is false. The
connector register happens when drm_dev_register() is invoked; the same
issue exists with drm_connector_unregister(). Therefore, this commit
removes the unnecessary call to drm_connector_register() and
drm_connector_unregister().
Changes since v2:
* Remove unnecessary call to drm_connector_unregister()
* Remove unused label
Signed-off-by: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com>
Reviewed-by: Daniel Vetter <daniel@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20190315161142.23gfu32lueyqrmyq@smtp.gmail.com
drm-misc-next for v5.3, try #2:
UAPI Changes:
- Add HDR source metadata property.
- Make drm.h compile on GNU/kFreeBSD by including stdint.h
- Clarify how the userspace reviewer has to review new kernel UAPI.
- Clarify that for using new UAPI, merging to drm-next or drm-misc-next should be enough.
Cross-subsystem Changes:
- video/hdmi: Add unpack function for DRM infoframes.
- Device tree bindings:
* Updating a property for Mali Midgard GPUs
* Updating a property for STM32 DSI panel
* Adding support for FriendlyELEC HD702E 800x1280 panel
* Adding support for Evervision VGG804821 800x480 5.0" WVGA TFT panel
* Adding support for the EDT ET035012DM6 3.5" 320x240 QVGA 24-bit RGB TFT.
* Adding support for Three Five displays TFC S9700RTWV43TR-01B 800x480 panel
with resistive touch found on TI's AM335X-EVM.
* Adding support for EDT ETM0430G0DH6 480x272 panel.
- Add OSD101T2587-53TS driver with DT bindings.
- Add Samsung S6E63M0 panel driver with DT bindings.
- Add VXT VL050-8048NT-C01 800x480 panel with DT bindings.
- Dma-buf:
- Make mmap callback actually optional.
- Documentation updates.
- Fix debugfs refcount inbalance.
- Remove unused sync_dump function.
- Fix device tree bindings in drm-misc-next after a botched merge.
Core Changes:
- Add support for HDR infoframes and related EDID parsing.
- Remove prime sg_table caching, now done inside dma-buf.
- Add shiny new drm_gem_vram helpers for simple VRAM drivers;
with some fixes to the new API on top.
- Small fix to job cleanup without timeout handler.
- Documentation fixes to drm_fourcc.
- Replace lookups of drm_format with struct drm_format_info;
remove functions that become obsolete by this conversion.
- Remove double include in bridge/panel.c and some drivers.
- Remove drmP.h include from drm/edid and drm/dp.
- Fix null pointer deref in drm_fb_helper_hotplug_event().
- Remove most members from drm_fb_helper_crtc, only mode_set is kept.
- Remove race of fb helpers with userspace; only restore mode
when userspace is not master.
- Move legacy setup from drm_file.c to drm_legacy_misc.c
- Rework scheduler job destruction.
- drm/bus was removed, remove from TODO.
- Add __drm_atomic_helper_crtc_reset() to subclass crtc_state,
and convert some drivers to use it (conversion is not complete yet).
- Bump vblank timeout wait to 100 ms for atomic.
- Docbook fix for drm_hdmi_infoframe_set_hdr_metadata.
Driver Changes:
- sun4i: Use DRM_GEM_CMA_VMAP_DRIVER_OPS instead of definining manually.
- v3d: Small cleanups, adding support for compute shaders,
reservation/synchronization fixes and job management refactoring,
fixes MMU and debugfs.
- lima: Fix null pointer in irq handler on startup, set default timeout for scheduled jobs.
- stm/ltdc: Assorted fixes and adding FB modifier support.
- amdgpu: Avoid hw reset if guilty job was already signaled.
- virtio: Add seqno to fences, add trace events, use correct flags for fence allocation.
- Convert AST, bochs, mgag200, vboxvideo, hisilicon to the new drm_gem_vram API.
- sun6i_mipi_dsi: Support DSI GENERIC_SHORT_WRITE_2 transfers.
- bochs: Small fix to use PTR_RET_OR_ZERO and driver unload.
- gma500: header fixes
- cirrus: Remove unused files.
- mediatek: Fix compiler warning after merging the HDR series.
- vc4: Rework binner bo handling.
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/052875a5-27ba-3832-60c2-193d950afdff@linux.intel.com
Add SPDX license identifiers to all Make/Kconfig files which:
- Have no license information of any form
These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:
GPL-2.0-only
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When the vblank irq happens, kernel time subsystem executes
`vkms_vblank_simulate`. In parallel or not, it prepares all stuff
necessary to the next vblank with arm, and it must flush these stuff
before the next vblank irq. However, vblank counter is ahead when arm is
executed in parallel with handle vblank.
CPU 0: CPU 1:
| |
atomic_commit_tail is ongoing |
| |
| hrtimer: vkms_vblank_simulate()
| |
| drm_crtc_handle_vblank()
| |
drm_crtc_arm_vblank() |
| |
->get_vblank_timestamp() |
| |
| hrtimer_forward_now()
Then, we should guarantee that the vblank interval time is correct (not
changed) before finish the vblank handle.
Fix the bug including the call to `hrtimer_forward_now()` in the same
lock of `drm_crtc_handle_vblank()` to ensure that the timestamp update
is correct when finish the vblank handle.
Signed-off-by: Shayenne Moura <shayenneluzmoura@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Reviewed-by: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com>
Signed-off-by: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/e2e4b8f3a5cab7b2dba75bf1930f86b0a4ee08c9.1548856186.git.shayenneluzmoura@gmail.com
kms_flip tests are breaking on vkms when simulate vblank because vblank
event sequence count returns one extra frame after arm vblank event to
make a page flip.
When vblank interrupt happens, userspace processes the vblank event and
issues the next page flip command. Kernel calls queue_work to call
commit_planes and arm the new page flip. The next vblank picks up the
newly armed vblank event and vblank interrupt happens again.
The arm and vblank event are asynchronous, then, on the next vblank, we
receive x+2 from `get_vblank_timestamp`, instead x+1, although timestamp
and vblank seqno matches.
Function `get_vblank_timestamp` is reached by 2 ways:
- from `drm_mode_page_flip_ioctl`: driver is doing one atomic
operation to synchronize planes in the same output. There is no
vblank simulation, the `drm_crtc_arm_vblank_event` function adds 1
on vblank count, and the variable in_vblank_irq is false
- from `vkms_vblank_simulate`: since the driver is doing a vblank
simulation, the variable in_vblank_irq is true.
Fix this problem subtracting one vblank period from vblank_time when
`get_vblank_timestamp` is called from trace `drm_mode_page_flip_ioctl`,
i.e., is not a real vblank interrupt, and getting the timestamp and
vblank seqno when it is a real vblank interrupt.
The reason for all this is that get_vblank_timestamp always supplies the
timestamp for the next vblank event. The hrtimer is the vblank
simulator, and it needs the correct previous value to present the next
vblank. Since this is how hw timestamp registers work and what the
vblank core expects.
Signed-off-by: Shayenne Moura <shayenneluzmoura@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Reviewed-by: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com>
Signed-off-by: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/171e6e1c239cbca0c3df7183ed8acdfeeace9cf4.1548856186.git.shayenneluzmoura@gmail.com
crtc_state is accessed by both vblank_handle() and the ordered
work_struct handle vkms_crc_work_handle() to retrieve and or update
the frame number for computed CRC.
Since work_struct can fail, add frame_end to account for missing frame
numbers.
Use (frame_[start/end]) for synchronization between hrtimer callback
and ordered work_struct handle.
This patch passes the following subtests from igt kms_pipe_crc_basic test:
bad-source, read-crc-pipe-A, read-crc-pipe-A-frame-sequence,
nonblocking-crc-pipe-A, nonblocking-crc-pipe-A-frame-sequence
Signed-off-by: Haneen Mohammed <hamohammed.sa@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20180903211743.GA2773@haneenDRM
This patch implement the necessary functions to compute and add CRCs
entries:
- Implement the set_crc_source() callback.
- Compute CRC using crc32 on the visible part of the framebuffer.
- Use ordered workqueue per output to compute and add CRC at the end
of a vblank.
- Use appropriate synchronization methods since the CRC computation must
be atomic wrt the generated vblank event for a given atomic update, by
using spinlock across atomic_begin/atomic_flush to wrap the event
handling code completely and match the flip event with the CRC.
Since vkms_crc_work_handle() can sleep, spinlock can't be acquired
while accessing vkms_output->primary_crc to compute CRC.
To make sure the data is updated and released without conflict with
the vkms_crc_work_handle(), the work_struct is flushed @crtc_destroy
and the data is updated before scheduling the work handle again, as
follow:
* CRC data update:
1- store vkms_crc_data {fb, src} per plane_state
2- @plane_duplicate_state -> allocate vkms_crc_data
3- during atomic commit (@atomic_update) ->
a) copy {fb, src} to plane_state->crc_data
b) get reference to fb,
3- @plane_destroy_state -> a) if (fb refcount) remove reference to fb
b) deallocate crc_data
* Atomic Commit:
1- vkms_plane_atomic_check
2- vkms_prepare_fb -> vmap vkms_gem_obj->vaddr
3- atomic_begin -> hold crc spinlock
4- atomic_plane_update -> a) update vkms_output->primary_crc
b) get reference to fb
5- atomic_flush -> a) send vblank event while holding event_lock
b) release crc spinlock
* hrtimer regular callback:
1- hold crc spinlock
2- drm_crtc_handle_vblank()
3- queue vkms_crc_work_handle
4- release crc spinlock
* cleanup:
1- @cleanup_fb ->vunmap vkms_gem_obj->vaddr
2- @crtc_destroy -> flush work struct
3- @plane_destroy -> a) if (fb refcount) remove reference to fb
b) deallocate crc_data
Signed-off-by: Haneen Mohammed <hamohammed.sa@gmail.com>
[seanpaul fixed typo in vkms_crtc s/vblamk/vblank/]
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/b948327f48c3e70ab232b4a0848ee6d033b26484.1533171495.git.hamohammed.sa@gmail.com
Currently, vkms shows an error message if the following steps occur: (1)
load vkms, (2) perform any specific operation in the vkms (e.g., run an
IGT test), and (3) unload the module. The following error message
emerges:
[drm:drm_mode_config_cleanup [drm]] *ERROR* connector Virtual-1 leaked!
This commit fixes this error by calling drm_atomic_helper_shutdown()
before drm_mode_config_cleanup, which turns off the whole display
pipeline and remove a reference related to any connector.
Signed-off-by: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180719004045.hzepp565x5lfco3c@smtp.gmail.com
This commit adds regular vblank events simulated through hrtimers, which
is a feature required by VKMS to mimic real hardware. Additionally, all
the vblank event send after pageflip is kept in the atomic_flush
function.
Changes since V1:
- Compute the vblank timer interval per interruption
Ville Syrjälä and Daniel Vetter:
- Removes hardcoded vblank interval to get it from user space
Changes since V2:
Chris Wilson
- Removes unnecessary algorithm to compute the next period
Daniel Vetter:
- Uses drm_calc_timestamping_constants to get the vblank interval
instead of calculating it manually
- Adds disable_vblank helper that turns of crtc
- Simplifies implementation by using drm_crtc_arm_vblank_event
- Replaces the code in atomic_begin to atomic_flush
- Removes unnecessary field in vkms_output
Changes since V3:
Daniel Vetter:
- Squash "drm/vkms: Add atomic helpers functions" into the commit that
handling vblank events simulated by hrtimers
Signed-off-by: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/7709bba40782ec06332d57fff337797b272581fc.1531359228.git.rodrigosiqueiramelo@gmail.com
