We used to protect minor-lookup and setup by the global drm lock. To
continue our attempts of dropping drm_global_mutex, this patch makes the
minor management independent of it. Furthermore, we make it all atomic and
switch to spin-locks instead of a mutex.
Now that minor-lookup is independent, we also move the
"drm_is_unplugged()" test into the minor-lookup path. There is no reason
to ever return a minor for unplugged objects, so keep that logic internal.
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
We can significantly simplify this helper by using plain multiplication.
Note that we converted the minor-type to an enum earlier so this didn't
work before.
We also fix a minor range-bug here: the limit argument of idr_alloc() is
*exclusive*, not inclusive, so we should use 64 instead of 63 as offset.
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Whenever we access minor->device, we are in a minor->kdev->...->fops
callback so the minor->kdev pointer *must* be valid. Thus, simply use
minor->kdev->devt instead of minor->device and remove the redundant field.
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
No need to check for DEBUGFS, we already have dummy-fallbacks in our
headers.
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
drm_get_minor() no longer allocates objects, and drm_unplug_minor() is now
the exact reverse of it. Rename it to _register/unregister() so their
name actually says what they do.
Furthermore, remove the direct minor-ptr and instead pass the minor-type.
This way we know the actual slot of the minor and can reset it if
required.
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
_put/get() are used for ref-counting, which we clearly don't do here.
Rename it to _free() and also use the common drm_minor_* prefix.
Furthermore, avoid passing the minor directly but instead use the type
like the other functions do, this allows us to reset the slot.
We also drop the redundant call to drm_unplug_minor() as drm_minor_free()
is only used from paths were that has already be called.
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Instead of waiting for device-registration, we now allocate minor-objects
during device allocation. The minors are not registered or assigned an ID.
This is still postponed to device-registration.
While at it, remove the superfluous output-parameter in drm_get_minor().
The reason for this early allocation is to make
dev->primary/control/render available atomically. So once the device is
alive, all of them are already set and we never have the situation where
one of them is set after another (they're either NULL or set, but never
changed). This will eventually allow us to reduce minor-ID allocation to
one base-ID instead of a single ID for each.
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Instead of accessing drm_minors_idr directly, this adds a small helper to
hide the internals. This will help us later to remove the drm_global_mutex
requirement for minor-lookup.
Furthermore, this also makes sure that minor->dev is always valid and
takes a reference-count to the device as long as the minor is used in an
open-file. This way, "struct file*"->private_data->dev is guaranteed to be
valid (which it has to, as we cannot reset it).
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Lets not trick ourselves into thinking "drm_device" objects are not
ref-counted. That's just utterly stupid. We manage "drm_minor" objects on
each drm-device and each minor can have an unlimited number of open
handles. Each of these handles has the drm_minor (and thus the drm_device)
as private-data in the file-handle. Therefore, we may not destroy
"drm_device" until all these handles are closed.
It is *not* possible to reset all these pointers atomically and restrict
access to them, and this is *not* how this is done! Instead, we use
ref-counts to make sure the object is valid and not freed.
Note that we currently use "dev->open_count" for that, which is *exactly*
the same as a reference-count, just open coded. So this patch doesn't
change any semantics on DRM devices (well, this patch just introduces the
ref-count, anyway. Follow-up patches will replace open_count by it).
Also note that generic VFS revoke support could allow us to drop this
ref-count again. We could then just synchronously disable any fops->xy()
calls. However, this is not the case, yet, and no such patches are
in sight (and I seriously question the idea of dropping the ref-cnt
again).
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Use enum for DRM_MINOR_* constants to avoid hard-coding the IDs.
Furthermore, add a DRM_MINOR_CNT so we can perform range-checks in
follow-ups.
This changes the IDs of the minor-types by -1, but they're not used as
indices so this is fine.
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The drm_open_helper() function is only used internally for drm_open() so
we can safely pass in the minor-object directly instead of the minor-id.
This way, we avoid the additional minor IDR lookup, which we already do
twice in drm_stub_open() and drm_open().
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
These members are all managed by DRM-core, lets group them together so
they're not split across the whole device.
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
With dev->anon_inode we have a global address_space ready for operation
right from the beginning. Therefore, there is no need to do a delayed
setup with TTM. Instead, set dev_mapping during initialization in
ttm_bo_device_init() and remove any "if (dev_mapping)" conditions.
Cc: Dave Airlie <airlied@redhat.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Cc: Alex Deucher <alexdeucher@gmail.com>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
DRM drivers share a common address_space across all character-devices of a
single DRM device. This allows simple buffer eviction and mapping-control.
However, DRM core currently waits for the first ->open() on any char-dev
to mark the underlying inode as backing inode of the device. This delayed
initialization causes ugly conditions all over the place:
if (dev->dev_mapping)
do_sth();
To avoid delayed initialization and to stop reusing the inode of the
char-dev, we allocate an anonymous inode for each DRM device and reset
filp->f_mapping to it on ->open().
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Our current DRM design uses a single address_space for all users of the
same DRM device. However, there is no way to create an anonymous
address_space without an underlying inode. Therefore, we wait for the
first ->open() callback on a registered char-dev and take-over the inode
of the char-dev. This worked well so far, but has several drawbacks:
- We screw with FS internals and rely on some non-obvious invariants like
inode->i_mapping being the same as inode->i_data for char-devs.
- We don't have any address_space prior to the first ->open() from
user-space. This leads to ugly fallback code and we cannot allocate
global objects early.
As pointed out by Al-Viro, fs/anon_inode.c is *not* supposed to be used by
drivers for anonymous inode-allocation. Therefore, this patch follows the
proposed alternative solution and adds a pseudo filesystem mount-point to
DRM. We can then allocate private inodes including a private address_space
for each DRM device at initialization time.
Note that we could use:
sysfs_get_inode(sysfs_mnt->mnt_sb, drm_device->dev->kobj.sd);
to get access to the underlying sysfs-inode of a "struct device" object.
However, most of this information is currently hidden and it's not clear
whether this address_space is suitable for driver access. Thus, unless
linux allows anonymous address_space objects or driver-core provides a
public inode per device, we're left with our own private internal mount
point.
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
There is no need to initialize this variable, so drop it. Otherwise, the
compiler won't warn if we use it unintialized.
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Lets make sure some basic expressions are always true:
bpp != NULL
width != NULL
height != NULL
stride = bpp * width < 2^32
size = stride * height < 2^32
PAGE_ALIGN(size) < 2^32
At least the udl driver doesn't check for multiplication-overflows, so
lets just make sure it will never happen. These checks allow drivers to do
any 32bit math without having to test for mult-overflows themselves.
The two divisions might hurt performance a bit, but dumb_create() is only
used for scanout-buffers, so that should be fine. We could use 64bit math
to avoid the divisions, but that may be slow on 32bit machines.. Or maybe
there should just be a "safe_mult32()" helper, which currently doesn't
exist (I think?).
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
All drivers currently need to clean up the vma-node manually. There is no
fancy logic involved so lets just clean it up unconditionally. The
vma-manager correctly catches multiple calls so we are fine.
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Probably a typo.. we obviously need "(bpp + 7) / 8" instead of
"(bpp + 1) / 8". Unlikely to be hit in any sane code, but lets be safe.
Use DIV_ROUND_UP() to avoid the problem entirely and make the core more
readable.
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
We need to call dma_buf_end_cpu_access() in case a damage-request.
Unlikely, but might happen during device unplug.
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
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
