It never fails and no one ever checked anyway.
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
There's a neat FIXME asking whether this is really need. I'd
say really no.
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
I want to also include kerneldoc from the header (for static inline
functions and structs), but fishing the right pieces out of a giant
header is a real pain. So split things out.
Note that it's not a really clean header with sane include orders, but
given's drm historical knack for giant headers detangling this is a
major task.
v2: Also extract struct drm_cmdline_mode.
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Makes more sense and gives better grouping in the DocBook function
reference sections. To make this possible we need to expose two
functions from drm_crtc.c though. To avoid further namespace pollution
in the system wide headers create a new internal header for such drm
internal symbols.
I expect that longer-term we'll add tons more, but since my goal here
is to polish the kerneldoc that's for another day.
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
There's not really any value in stating that no locking is needed. And
even if the comment is useful, a check for the right mutex at the
beginning of the function is better since that can't be ingored as
easily as a bit of documentation.
Note that drm_mode_probed_add in drm_crtc.c is also changed, the next
patch will move this into drm_modes.c
v2: Don't add locking WARN_ONs where it is not strictly required (i.e.
the two functions to validate/prune mode lists).
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
And clean it up so that there's no kerneldoc warnings. There's still a
lot to do with this one here.
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
It's only used by imx, and that one gets it wrong - there's no need
to deteach the encoder before removing it.
And really, neither current drm modesetting code nor all the userspace
we have can handle dynamic changes in the set of possible encoders for
a given connector. So let's just remove this before someone starts
doing something really nasty with it.
As a plus, one less kerneldoc comment to write.
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
While at it do a tiny bit of interface cleanup and convert boolean
return values to bool. With this patch all exported functions and inline
helpers which are part of the drm_mm public interface are documented.
Also drop superflous extern function modifiers since most of drm_mm.h
doesn't use them - more consistent that way.
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
kerneldoc polish will follow in the next patch.
Hopefully documenting the lru scan support a bit better spurs someone
to give this a shot in the ttm eviction code. At least in i915 it
helped quite a lot with memory thrashing on platforms where eviction
was (we've fixed that too meanwhile) fairly expensive.
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This was missed in
commit c700c67bae
Author: David Herrmann <dh.herrmann@gmail.com>
Date: Sat Jul 27 13:39:28 2013 +0200
drm/mm: remove unused API
Cc: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
I've done quite a bit of cleanups, clarifications and mostly
integrating kerneldoc. So I guess I should add myself.
Also split up the copyright notices per holder to make it clear which
year ranges are covered.
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
For giant hilarity the DocBook reference overview is only generated
when in a level 2 section, not in a level 3 section. So we need to
move this up a bit as a side-by-side section to the main PRIME
documentation.
Whatever.
To have a complete set of references add the missing kerneldoc for all
functions exported to modules with the exception of the file private
init/destroy functions - drivers have no business calling those, so
let's just drop the EXPORT_SYMBOL instead.
Also reflow the function parameters to align correctly and break at 80
chars - my OCD couldn't stand them while writing the kerneldoc ;-)
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
PRIME fds aren't actually GEM fds but are (like the modeset API)
independent of the underlying buffer manager, as long as that one uses
uint32_t as handles. So move that entire section out of the GEM
section and reword it a bit to clarify which parts of PRIME are
generic, and which are the mandatory pieces for GEM drivers to
correctly implement the GEM lifetime rules. The rewording mostly
consists of not mixing up GEM, PRIME and DRM.
I've considered adding some blurbs to the GEM object lifetime section
about interactions with dma-bufs, but then dropped that. As long as
drivers use the right helpers they should have this all implemented
correctly and hence can be regarded as an implementation detail of the
PRIME/GEM helpers. So no need to confuse driver writers with those
tricky interactions.
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Thierry created such nice kerneldocs, it's a shame we've left them
lingering!
For the fun of it also add a bit of kerneldoc to the header so that we
can also include that. Just in case someone adds kerneldoc in there.
Cc: Thierry Reding <thierry.reding@gmail.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
By consolidating them all into one section at the very end. And to
make double-sure that no one gets confused start with a stern warning
against any use of them. And prefix all subsections with "Legacy".
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Stumbled over while reviewing all occurences in the DRM doc talking
about suspend/resume.
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Those all died with
commit 0111be4218
Author: Ville Syrjälä <ville.syrjala@linux.intel.com>
Date: Fri Oct 4 14:53:41 2013 +0300
drm: Kill drm perf counter leftovers
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This should be done in the driver chapter instead.
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Currently it's sitting in the mode setting helper section, which isn't
quite right. Looks much better in the memory management section next
to TTM and GEM.
Cc: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Split up the DocBook into the core drm part and a 2nd part for
driver documentation. As an example add a very (very!) basic
skeleton for i915.
v1: Typo fixes from Dieter.
Cc: Dieter Nützel <Dieter@nuetzel-hh.de>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The stylesheet doesn't allow this in normal paragraphs.
Cc: David Herrmann <dh.herrmann@gmail.com>
Acked-by: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
v2: Also do s/RETURNS/Returns/, less yelling in docs is always good.
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
- This is _not_ a generic interface to create gem objects, but just an
interface to make early boot services (like boot splash) with a
generic KMS userspace driver possible. Hence it's better to move
the documentation for this from the GEM section to the KMS section,
next to the creation of framebuffer objects.
- Make it really clear that the returned handle isn't necessarily a
GEM object (it can also be e.g. a TTM handle when running on top of
vmwgfx).
- Add a paragraph to make it clear that this is just for unaccelarated
userspace - gpu drivers need to have their own buffer object
creation ioctl which is hardware specific.
v2: Clarify that the documentation doesn't just apply to GEM-based
drivers only but is now generally valid, as suggested by David.
v3: Polish the intro sentence a bit and one s/objects/handles/ for
clarification, both suggested by Laurent.
v4: More text polish from Laurent's review.
v5: More typo fixes from Dieter.
Cc: Dieter Nützel <Dieter@nuetzel-hh.de>
Cc: David Herrmann <dh.herrmann@gmail.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
this is the second pull request for 3.15 radeon changes. Highlights this time:
- Better VRAM usage
- VM page table rework
- Enabling different UVD clocks again
- Some general cleanups and improvements
* 'drm-next-3.15' of git://people.freedesktop.org/~deathsimple/linux:
drm/radeon: remove struct radeon_bo_list
drm/radeon: drop non blocking allocations from sub allocator
drm/radeon: remove global vm lock
drm/radeon: use normal BOs for the page tables v4
drm/radeon: further cleanup vm flushing & fencing
drm/radeon: separate gart and vm functions
drm/radeon: fix VCE suspend/resume
drm/radeon: fix missing bo reservation
drm/radeon: limit how much memory TTM can move per IB according to VRAM usage
drm/radeon: validate relocations in the order determined by userspace v3
drm/radeon: add buffers to the LRU list from smallest to largest
drm/radeon: deduplicate code in radeon_gem_busy_ioctl
drm/radeon: track memory statistics about VRAM and GTT usage and buffer moves v2
drm/radeon: add a way to get and set initial buffer domains v2
drm/radeon: use variable UVD clocks
drm/radeon: cleanup the fence ring locking code
drm/radeon: improve ring lockup detection code v2
Just move all fields into radeon_cs_reloc, removing unused/duplicated fields.
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
- Fix the execbuf rebind performance regression due to topic/ppgtt (Chris).
- Fix up the connector cleanup ordering for sdvod i2c and dp aux devices (Imre).
- Try to preserve the firmware modeset config on driver load. And a bit of prep
work for smooth takeover of the fb contents (Jesse).
- Prep cleanup for larger gtt address spaces on bdw (Ben).
- Improve our vblank_wait code to make hsw modesets faster (Paulo).
- Display debugfs file (Jesse).
- DRRS prep work from Vandana Kannan.
- pipestat interrupt handler to fix a few races around vblank/pageflip handling
on byt (Imre).
- Improve display fuse handling for display-less SKUs (Damien).
- Drop locks while stalling for the gpu when serving pagefaults to improve
interactivity (Chris).
- And as usual piles of other improvements and small fixes all over.
* tag 'drm-intel-next-2014-02-14' of ssh://git.freedesktop.org/git/drm-intel: (65 commits)
drm/i915: fix NULL deref in the load detect code
drm/i915: Only bind each object rather than for every execbuffer
drm/i915: Directly return the vma from bind_to_vm
drm/i915: Simplify i915_gem_object_ggtt_unpin
drm/i915: Allow blocking in the PDE alloc when running low on gtt space
drm/i915: Don't allocate context pages as mappable
drm/i915: Handle set_cache_level errors in the status page setup
drm/i915: Don't pin the status page as mappable
drm/i915: Don't set PIN_MAPPABLE for legacy ringbuffers
drm/i915: Handle set_cache_level errors in the pipe control scratch setup
drm/i915: split PIN_GLOBAL out from PIN_MAPPABLE
drm/i915: Consolidate binding parameters into flags
drm/i915: sdvo: add i2c sysfs symlink to the connector's directory
drm/i915: sdvo: fix error path in sdvo_connector_init
drm/i915: dp: fix order of dp aux i2c device cleanup
drm/i915: add unregister callback to connector
drm/i915: don't reference null pointer at i915_sink_crc
drm/i915/lvds: Remove dead code from failing case
drm/i915: don't preserve inherited configs with nothing on v2
drm/i915/bdw: Split up PPGTT cleanup
...
No need to make it more complicated than necessary,
just allocate the page tables as normal BO and
flush whenever the address change.
v2: update comments and function name
v3: squash bug fixes, page directory and tables patch
v4: rebased on Mareks changes
Signed-off-by: Christian König <christian.koenig@amd.com>
Userspace should set the first 4 bits of drm_radeon_cs_reloc::flags to
a number from 0 to 15. The higher the number, the higher the priority,
which means a buffer with a higher number will be validated sooner.
The old behavior is preserved: Buffers used for write are prioritized over
read-only buffers if the userspace doesn't set the number.
v2: add buffers to buckets directly, then concatenate them
v3: use a stable sort
Signed-off-by: Marek Olšák <marek.olsak@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
The statistics are:
- VRAM usage in bytes
- GTT usage in bytes
- number of bytes moved by TTM
The last one is actually a counter, so you need to sample it before and after
command submission and take the difference.
This is useful for finding performance bottlenecks. Userspace queries are
also added.
v2: use atomic64_t
Signed-off-by: Marek Olšák <marek.olsak@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
When passing buffers between processes, the receiving process needs to know
the original buffer domain, so that it doesn't accidentally move the buffer.
v2: reserve the buffer
Signed-off-by: Marek Olšák <marek.olsak@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Now that Christian fixed the performance problems with
the feedback buffer in mesa, we can enable variable UVD
clocks. There are multiple UVD power states associated
with different types and numbers of streams. This uses
the appropriate state based on that information rather
than always using the fastest UVD clocks which saves some
power. One possible downside is that this may adversely
affect decode benchmarks since these power states target
specific playback requirements rather than maximum
performance. If that becomes an issue, we can add a
sysfs attribute to force the max UVD state.
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
We no longer need to take the ring lock while checking for
a gpu lockup, so just cleanup the code.
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Use atomics and jiffies_64, so that we don't need to have the
ring mutex locked any more and avoid wrap arounds.
v2: fix some checkpatch warnings
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
So this is the initial pull request for radeon drm-next 3.15. Highlights:
- VCE bringup including DPM support
- Few cleanups for the ring handling code
* 'drm-next-3.15' of git://people.freedesktop.org/~deathsimple/linux:
drm/radeon: cleanup false positive lockup handling
drm/radeon: drop radeon_ring_force_activity
drm/radeon: drop drivers copy of the rptr
drm/radeon/cik: enable/disable vce cg when encoding v2
drm/radeon: add support for vce 2.0 clock gating
drm/radeon/dpm: properly enable/disable vce when vce pg is enabled
drm/radeon/dpm: enable dynamic vce state switching v2
drm/radeon: add vce dpm support for KV/KB
drm/radeon: enable vce dpm on CI
drm/radeon: add vce dpm support for CI
drm/radeon: fill in set_vce_clocks for CIK asics
drm/radeon/dpm: fetch vce states from the vbios
drm/radeon/dpm: fill in some initial vce infrastructure
drm/radeon/dpm: move platform caps fetching to a separate function
drm/radeon: add callback for setting vce clocks
drm/radeon: add VCE version parsing and checking
drm/radeon: add VCE ring query
drm/radeon: initial VCE support v4
drm/radeon: fix CP semaphores on CIK
Updates from Jean-Fracois for the TDA998x driver, which are on top of
the fixes you have previously pulled, except these changes aren't
intended for -rc, but the next merge window.
Several of these are issues of correctness - passing more correct HDMI
info packets, not reading registers in older chips documented as write
only (despite appearing to be read/write in later chips). Others are
code cleanups (using definitions rather than constants where we have
them already in the kernel).
Additional functionality is also added by way of optional support for
the IRQ from the TDA998x, which allows us to avoid busy-waiting for
the EDID reads.
* 'tda998x-devel' of git://ftp.arm.linux.org.uk/~rmk/linux-cubox:
drm/i2c: tda998x: always use the same device for all kernel messages
drm/i2c: tda998x: adjust the audio clock divider for S/PDIF
drm/i2c: tda998x: code optimization
drm/i2c: tda998x: remove the unused variable ca_i2s
drm/i2c: tda998x: make the audio code more readable
drm/i2c: tda998x: use irq for connection status and EDID read
drm/i2c: tda998x: always enable EDID read IRQ
drm/i2c: tda998x: add DT documentation
drm/i2c: tda998x: add DT support
drm/i2c: tda998x: don't read write-only registers
drm/i2c: tda998x: don't freeze the system at audio startup time
drm/i2c: tda998x: change probe message origin
drm/i2c: tda998x: code cleanup
drm/i2c: tda998x: clean up error chip version checking
drm/i2c: tda998x: check more I/O errors
drm/i2c: tda998x: simplify the i2c read/write functions
drm/i2c: tda998x: use ALSA IEC958 definitions and update audio frequency
drm/i2c: tda998x: add the active aspect in HDMI AVI frame
drm/i2c: tda998x: use HDMI constants
- Yet more steps towards atomic modeset from Ville.
- DP panel power sequencing improvements from Paulo.
- irq code cleanups from Ville.
- 5.4 GHz dp lane clock support for bdw/hsw from Todd.
- Clock readout support for hsw/bdw (aka fastboot) from Jesse.
- Make pipe underruns report at ERROR level (Ville). This is to check our
improved watermarks code.
- Full ppgtt support from Ben for gen7.
- More fbc fixes and improvements from Ville all over the place, unfortunately
not yet enabled by default on more platforms.
- w/a cleanups from Ville.
- HiZ stall optimization settings (Chia-I Wu).
- Display register mmio offset refactor patch from Antti.
- RPS improvements for corner-cases from Jeff McGee.
* tag 'drm-intel-next-2014-02-07' of ssh://git.freedesktop.org/git/drm-intel: (166 commits)
drm/i915: Update rps interrupt limits
drm/i915: Restore rps/rc6 on reset
drm/i915: Prevent recursion by retiring requests when the ring is full
drm/i915: Generate a hang error code
drm/i915: unify FLIP_DONE macro names
drm/i915: vlv: s/spin_lock_irqsave/spin_lock/ in irq handler
drm/i915: factor out valleyview_pipestat_irq_handler
drm/i915: vlv: don't unmask IIR[DISPLAY_PIPE_A/B_VBLANK] interrupt
drm/i915: Reorganize display pipe register accesses
drm/i915: Treat using a purged buffer as a source of EFAULT
drm/i915: Convert EFAULT into a silent SIGBUS
drm/i915: release mutex in i915_gem_init()'s error path
drm/i915: check for oom when allocating private_default_ctx
drm/i915/vlv: WA to fix Voltage not getting dropped to Vmin when Gfx is power gated.
drm/i915: Get rid of acthd based guilty batch search
drm/i915: Use hangcheck score to find guilty context
drm/i915: Drop WaDisablePSDDualDispatchEnable:ivb for IVB GT2
drm/i915: Fix IVB GT2 WaDisableDopClockGating and WaDisablePSDDualDispatchEnable
drm/i915: Don't access snooped pages through the GTT (even for error capture)
drm/i915: Only print information for filing bug reports once
...
Conflicts:
drivers/gpu/drm/i915/intel_dp.c
This series of patches implements a small framework that abstracts away
some of the functionality that the DisplayPort AUX channel provides. It
comes with a set of generic helpers that use the driver implementations
to reduce code duplication.
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Merge tag 'drm/dp-aux-for-3.15-rc1' of git://anongit.freedesktop.org/tegra/linux into drm-next
drm: DisplayPort AUX framework for v3.15-rc1
This series of patches implements a small framework that abstracts away
some of the functionality that the DisplayPort AUX channel provides. It
comes with a set of generic helpers that use the driver implementations
to reduce code duplication.
* tag 'drm/dp-aux-for-3.15-rc1' of git://anongit.freedesktop.org/tegra/linux:
drm/dp: Allow registering AUX channels as I2C busses
drm/dp: Add DisplayPort link helpers
drm/dp: Add drm_dp_dpcd_read_link_status()
drm/dp: Add AUX channel infrastructure
Implements an I2C-over-AUX I2C adapter on top of the generic drm_dp_aux
infrastructure. It extracts the retry logic from existing drivers, which
should help in porting those drivers to this new helper.
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
---
Changes in v5:
- move comments partially to to header file
- keep MOT set between I2C messages
- return -EPROTO on short reads
Changes in v4:
- fix typo "bitrate" -> "bit rate"
Changes in v3:
- add back DRM_DEBUG_KMS and DRM_ERROR messages
- embed i2c_adapter within struct drm_dp_aux
- fix typo in comment
Add a helper to probe a DP link (read out the supported DPCD revision,
maximum rate, link count and capabilities) as well as power up the DP
link and configure it accordingly.
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
---
Changes in v5:
- export helpers
Changes in v4:
- fix a couple of typos in comments as pointed out by Alex Deucher
Changes in v3:
- split into drm_dp_link_power_up() and drm_dp_link_configure()
- do not change sink state for DPCD versions earlier than 1.1
- sleep for 1-2 ms after setting local sink to D0 state
- read and write consecutive registers where possible
- read DPCD revision when link is probed
- remove duplicate kerneldoc
The function reads the link status (6 bytes starting at offset 0x202)
from the DPCD so that it can be conveniently passed to other DPCD
helpers.
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
