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2020-03-26drm: Add docs for managed resourcesDaniel Vetter
All collected together to provide a consistent story in one patch, instead of the somewhat bumpy refactor-evolution leading to this. Also some thoughts on what the next steps could be: - Create a macro called devm_drm_dev_alloc() which essentially wraps the kzalloc(); devm_drm_dev_init(); drmm_add_final_kfree() combo. Needs to be a macro since we'll have to do some typeof trickery and casting to make this fully generic for all drivers that embed struct drm_device into their own thing. - A lot of the simple drivers now have essentially just drm_dev_unplug(); drm_atomic_helper_shutdown(); as their $bus_driver->remove hook. We could create a devm_mode_config_reset which sets drm_atomic_helper_shutdown as it's cleanup action, and a devm_drm_dev_register with drm_dev_unplug as it's cleanup action, and simple drivers wouldn't have a need for a ->remove function at all, and we could delete them. - For more complicated drivers we need drmm_ versions of a _lot_ more things. All the userspace visible objects (crtc, plane, encoder, crtc), anything else hanging of those (maybe a drmm_get_edid, at least for panels and other built-in stuff). Also some more thoughts on why we're not reusing devm_ with maybe a fake struct device embedded into the drm_device (we can't use the kdev, since that's in each drm_minor). - Code review gets extremely tricky, since every time you see a devm_ you need to carefully check whether the fake device (with the drm_device lifetim) or the real device (with the lifetim of the underlying physical device and driver binding) are used. That's not going to help at all, and we have enormous amounts of drivers who use devm_ where they really shouldn't. Having different types makes sure the compiler type checks this for us and ensures correctness. - The set of functions are very much non-overlapping. E.g. devm_ioremap makes total sense, drmm_ioremap has the wrong lifetime, since hw resources need to be cleaned out at driver unbind and wont outlive that like a drm_device. Similar, but other way round for drmm_connector_init (which is the only correct version, devm_ for drm_connector is just buggy). Simply not having the wrong version again prevents bugs. Finally I guess this opens a huge todo for all the drivers. I'm semi-tempted to do a tree-wide s/devm_kzalloc/drmm_kzalloc/ since most likely that'll fix an enormous amount of bugs and most likely not cause any issues at all (aside from maybe holding onto memory slightly too long). v2: - Doc improvements from Laurent. - Also add kerneldoc for the new drmm_add_action_or_reset. v3: - Remove kerneldoc for drmm_remove_action. Reviewed-by: Sam Ravnborg <sam@ravnborg.org> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: linux-doc@vger.kernel.org Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> fixup docs Link: https://patchwork.freedesktop.org/patch/msgid/20200323144950.3018436-52-daniel.vetter@ffwll.ch
2020-03-26drm: add managed resources tied to drm_deviceDaniel Vetter
We have lots of these. And the cleanup code tends to be of dubious quality. The biggest wrong pattern is that developers use devm_, which ties the release action to the underlying struct device, whereas all the userspace visible stuff attached to a drm_device can long outlive that one (e.g. after a hotunplug while userspace has open files and mmap'ed buffers). Give people what they want, but with more correctness. Mostly copied from devres.c, with types adjusted to fit drm_device and a few simplifications - I didn't (yet) copy over everything. Since the types don't match code sharing looked like a hopeless endeavour. For now it's only super simplified, no groups, you can't remove actions (but kfree exists, we'll need that soon). Plus all specific to drm_device ofc, including the logging. Which I didn't bother to make compile-time optional, since none of the other drm logging is compile time optional either. One tricky bit here is the chicken&egg between allocating your drm_device structure and initiliazing it with drm_dev_init. For perfect onion unwinding we'd need to have the action to kfree the allocation registered before drm_dev_init registers any of its own release handlers. But drm_dev_init doesn't know where exactly the drm_device is emebedded into the overall structure, and by the time it returns it'll all be too late. And forcing drivers to be able clean up everything except the one kzalloc is silly. Work around this by having a very special final_kfree pointer. This also avoids troubles with the list head possibly disappearing from underneath us when we release all resources attached to the drm_device. v2: Do all the kerneldoc at the end, to avoid lots of fairly pointless shuffling while getting everything into shape. v3: Add static to add/del_dr (Neil) Move typo fix to the right patch (Neil) v4: Enforce contract for drmm_add_final_kfree: Use ksize() to check that the drm_device is indeed contained somewhere in the final kfree(). Because we need that or the entire managed release logic blows up in a pile of use-after-frees. Motivated by a discussion with Laurent. v5: Review from Laurent: - %zu instead of casting size_t - header guards - sorting of includes - guarding of data assignment if we didn't allocate it for a NULL pointer - delete spurious newline - cast void* data parameter correctly in ->release call, no idea how this even worked before v6: Review from Sam - Add the kerneldoc for the managed sub-struct back in, even if it doesn't show up in the generated html somehow. - Explain why __always_inline. - Fix bisectability around the final kfree() in drm_dev_relase(). This is just interim code which will disappear again. - Some whitespace polish. - Add debug output when drmm_add_action or drmm_kmalloc fail. v7: My bisectability fix wasn't up to par as noticed by smatch. v8: Remove unecessary {} around if else v9: Use kstrdup_const, which requires kfree_const and introducing a free_dr() helper (Thomas). v10: kfree_const goes boom on the plain "kmalloc" assignment, somehow we need to wrap that in kstrdup_const() too!! Also renumber revision log, I somehow reset it midway thruh. Reviewed-by: Sam Ravnborg <sam@ravnborg.org> Cc: Thomas Zimmermann <tzimmermann@suse.de> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Cc: Neil Armstrong <narmstrong@baylibre.com Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20200324124540.3227396-1-daniel.vetter@ffwll.ch
2019-12-10drm/doc: Drop :c:func: markupDaniel Vetter
Kernel sphinx has learned how to do that in commit d74b0d31dddeac2b44c715588d53d9a1e5b1158e Author: Jonathan Corbet <corbet@lwn.net> Date: Thu Apr 25 07:55:07 2019 -0600 Docs: An initial automarkup extension for sphinx Unfortunately it hasn't learned that yet for structures, so we're stuck with the :c:type: noise for now still. Reviewed-by: Thierry Reding <treding@nvidia.com> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20191204101933.861169-1-daniel.vetter@ffwll.ch
2019-02-19drm/doc: document recommended component helper usageDaniel Vetter
Now that component has docs it's worth spending a few words and hyperlinks on recommended best practices in drm. v2: Add another item that component shouldn't be preferred over drm_bridge/panel and similar subsystems already providing specialized support for specific components (Laurent). Also convert to bullet list. Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Cc: Russell King - ARM Linux admin <linux@armlinux.org.uk> Reviewed-by: Maxime Ripard <maxime.ripard@bootlin.com> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20190212164615.13370-1-daniel.vetter@ffwll.ch
2019-01-29drm: Switch DRIVER_ flags to an enumDaniel Vetter
And move the documenation we alreay have into kerneldoc, plus a bit of polish while at it. v2: - Ditch FIXME from commit message, I've resolved that already before sending out the first version. - Put the legacy DRIVER_ flags at the end (Sam). Cc: Sam Ravnborg <sam@ravnborg.org> Reviewed-by: Emil Velikov <emil.velikov@collabora.com> Reviewed-by: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20190129104248.26607-2-daniel.vetter@ffwll.ch
2019-01-14drm: move drm_can_sleep() to drm_util.hSam Ravnborg
Move drm_can_sleep() out of drmP.h to allow users to get rid of the drmP.h include. There was no header file that was a good match for this helper function. So add this to drm_util with the relevant includes. Add include of drm_util.h to all users. v2: - Update comments to use kernel-doc style (Daniel) - Add FIXME to drm_can_sleep and add note that this function should not be used in new code (Daniel) v3: - Fix kernel-doc syntax (Daniel) - Plug drm_util.h into drm-internels.rst (Daniel) Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: Maxime Ripard <maxime.ripard@bootlin.com> Cc: Sean Paul <sean@poorly.run> Cc: David Airlie <airlied@linux.ie> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: Alex Deucher <alexander.deucher@amd.com> Cc: "Christian König" <christian.koenig@amd.com> Cc: "David (ChunMing) Zhou" <David1.Zhou@amd.com> Cc: Gerd Hoffmann <kraxel@redhat.com> Cc: Rob Clark <robdclark@gmail.com> Cc: Tomi Valkeinen <tomi.valkeinen@ti.com> Cc: Eric Anholt <eric@anholt.net> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: https://patchwork.freedesktop.org/patch/msgid/20190112193251.20450-2-sam@ravnborg.org
2019-01-11drm/doc: Polish kerneldoc for drm_device.hDaniel Vetter
- Move all the legacy gunk at the bottom, and exclude it from kerneldoc. - Documentation for the remaining bits. v2: Fix typo (Sam). Cc: Sam Ravnborg <sam@ravnborg.org> Acked-by: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20190111164048.29067-5-daniel.vetter@ffwll.ch
2017-06-27Merge remote-tracking branch 'airlied/drm-next' into drm-misc-nextSean Paul
Required for Daniel's drm_vblank_cleanup cleanup
2017-06-20drm/doc: Improve ioctl/fops docs a bit moreDaniel Vetter
I spotted a markup issue, plus adding the descriptions in drm_driver. Plus a few more links while at it. I'm still mildly unhappy with the split between fops and ioctls, but I still think having the ioctls in the uapi chapter makes more sense. Oh well ... v2: Rebase. v3: Move misplace hunk to the right patch. Cc: Stefan Agner <stefan@agner.ch> Acked-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/20170531092045.3950-1-daniel.vetter@ffwll.ch
2017-06-14drm: introduce sync objects (v4)Dave Airlie
Sync objects are new toplevel drm object, that contain a pointer to a fence. This fence can be updated via command submission ioctls via drivers. There is also a generic wait obj API modelled on the vulkan wait API (with code modelled on some amdgpu code). These objects can be converted to an opaque fd that can be passes between processes. v2: rename reference/unreference to put/get (Chris) fix leaked reference (David Zhou) drop mutex in favour of cmpxchg (Chris) v3: cleanups from danvet, rebase on drm_fops rename check fd_flags is 0 in ioctls. v4: export find/free, change replace fence to take a syncobj. In order to support lookup first, replace later semantics which seem in the end to be cleaner. Reviewed-by: Sean Paul <seanpaul@chromium.org> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Dave Airlie <airlied@redhat.com>
2017-06-01drm/doc: Polish irq helper documentationDaniel Vetter
Pull a (much shorter) overview into drm_irq.c, and instead put the callback documentation into in-line comments in drm_drv.h. v2: Move the include stanzas back to the split-up patch (Stefan). Cc: Stefan Agner <stefan@agner.ch> Reviewed-by: Stefan Agner <stefan@agner.ch> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/20170531092253.12833-1-daniel.vetter@ffwll.ch
2017-06-01drm: Extract drm_vblank.[hc]Daniel Vetter
drm_irq.c contains both the irq helper library (optional) and the vblank support (optional, but part of the modeset uapi, and doesn't require the use of the irq helpers at all. Split this up for more clarity of the scope of the individual bits. v2: Move misplaced hunks to this patch (Stefan). Cc: Stefan Agner <stefan@agner.ch> Reviewed-by: Stefan Agner <stefan@agner.ch> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/20170531092146.12528-1-daniel.vetter@ffwll.ch
2017-04-04drm: document drm_ioctl.[hc]Daniel Vetter
Also unify/merge with the existing stuff. I was a bit torn where to put this, but in the end I decided to put all the ioctl/sysfs/debugfs stuff into drm-uapi.rst. That means we have a bit a split with the other uapi related stuff used internally, like drm_file.[hc], but I think overall this makes more sense. If it's too confusing we can always add more cross-links to make it more discoverable. But the auto-sprinkling of links kernel-doc already does seems sufficient. Also for prettier docs and more cross-links, switch the internal defines over to an enum, as usual. v2: Update kerneldoc fro drm_compat_ioctl too (caught by 0day), plus a bit more drive-by polish. v3: Fix typo, spotted by xerpi on irc (Sergi). v4: Add missing space in comment (Neil). Cc: Sergi Granell <xerpi.g.12@gmail.com> Reviewed-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/20170404095304.17599-4-daniel.vetter@ffwll.ch
2017-03-14drm/doc: Consistent kerneldoc include orderDaniel Vetter
First overview text (if there is any), then headers (since generally you want to start out with the data structures), then all the other stuff with functions. Most of this is pre-shpinx, since with the old docbook only the overview stuff was pulled in directly. Everything else was put in a per-section index, so include order didn't really matter. Acked-by: Eric Anholt <eric@anholt.net> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/20170302151638.1882-4-daniel.vetter@ffwll.ch
2017-03-14drm/doc: Document drm_file.[hc]Daniel Vetter
Well, mostly drm_file.h, and clean up all related things: - I didnt' figure out the difference between preclose and postclose. The existing explanation in drm-internals.rst didn't convince me, since it's also really outdated - we clean up pending DRM events in the core nowadays. I put a FIXME in for the future. - Another FIXME is to have a macro for default fops. - Lots of links all around, main areas are to tie the overview in drm_file.c more into the callbacks in struct drm_device, and the other is to link render/primary node code to the right sections in drm-uapi.rst. - Also moved the open/close stuff to drm_drv.h from drm-internals.rst, seems like the better place for that information. Since that section was rather outdated this amounted to full-on rewrite. A big missing piece here is some overview graph, but I think better to wait with that one until drm_device and drm_driver are also fully documented. v2: Nits from Sean. Reviewed-by: Sean Paul <seanpaul@chromium.org> Reviewed-by: Liviu Dudau <Liviu.Dudau@arm.com> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/20170308141257.12119-12-daniel.vetter@ffwll.ch
2017-03-11Merge branch 'drm/next/platform' of git://linuxtv.org/pinchartl/media into ↵Daniel Vetter
drm-misc-next Merge Laurent's drm_platform removal code. Only conflict is with the drm_pci.h extraction, which allows me to fix up the misplayed drm_platform_init fumble that 0day and Stephen Rothwell reported. Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
2017-03-09drm: rename drm_fops.c to drm_file.cDaniel Vetter
It's not just file ops, but drm_file stuff in general. This is prep work to extracting a drm_file.h header in the next patch. Reviewed-by: Gustavo Padovan <gustavo.padovan@collabora.com> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/20170308141257.12119-8-daniel.vetter@ffwll.ch
2017-02-17drm: Remove unused drm_platform midlayerLaurent Pinchart
Now that the last driver has been converted, the drm_platform midlayer is unused. Remove it. Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch Reviewed-by: Sean Paul <seanpaul@chromium.org>
2016-11-15drm/print: Move kerneldoc next to definitionDaniel Vetter
kerneldoc expects the comment next to definitions, otherwise it can't pick up exported vs. internal stuff. This fixes a warning from the doc build done with: $ make DOCBOOKS="" htmldocs Fixes: d8187177b0b1 ("drm: add helper for printing to log or seq_file") Cc: Rob Clark <robdclark@gmail.com> Cc: Sean Paul <seanpaul@chromium.org> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/20161114115825.22050-8-daniel.vetter@ffwll.ch
2016-11-15drm: Clean up kerneldoc for struct drm_driverDaniel Vetter
Just cleans up what's there, still plenty missing. Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/20161114115825.22050-6-daniel.vetter@ffwll.ch
2016-11-08drm: add helper for printing to log or seq_fileRob Clark
Sometimes it is nice not to duplicate equivalent printk() and seq_printf() code. v2: simplify things w/ va_format, and use dev_printk, docs Signed-off-by: Rob Clark <robdclark@gmail.com> Signed-off-by: Sean Paul <seanpaul@chromium.org> Link: http://patchwork.freedesktop.org/patch/msgid/1478358492-30738-3-git-send-email-robdclark@gmail.com
2016-08-08drm: Mark up legacy/dri1 drivers with DRM_LEGACYDaniel Vetter
It's super confusing that new drivers need to be marked with DRIVER_MODESET when really it means DRIVER_MODERN. Much better to invert the meaning and rename it to something that's suitably off-putting. Since there's over 100 places using DRIVER_MODESET we need to roll out this change without a flag day. v2: Update docs. Reviewed-by: Frank Binns <frank.binns@imgtec.com> Reviewed-by: David Herrmann <dh.herrmann@gmail.com> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/1470251470-30830-1-git-send-email-daniel.vetter@ffwll.ch
2016-07-19drm/doc: Spinx leftoversDaniel Vetter
This is unfortunately not all the sphinx noise when building the gpu documentations. But the remaining warnings have completely bogus line and probably also file sources, and I just can't find them. Probably some serious debuggging of the line annotations in the sphinx/kernel-doc toolchain needed first. Acked-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/1468612088-9721-11-git-send-email-daniel.vetter@ffwll.ch
2016-07-12vga_switcheroo: Sphinxify docsLukas Wunner
Fix up formatting glitches remaining after the automatic rst conversion. Cc: Jonathan Corbet <corbet@lwn.net> Cc: Jani Nikula <jani.nikula@intel.com> Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/3a369602ae35fdbf5e4a12f7e172088c89fa27bb.1468225027.git.lukas@wunner.de
2016-06-21Documentation/gpu: split up mm, kms and kms-helpers from internalsJani Nikula
Make the documents more manageable. Signed-off-by: Jani Nikula <jani.nikula@intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/be992e56eb8442d6e03b52444df5a42525085718.1466506505.git.jani.nikula@intel.com
2016-06-21Documentation/gpu: convert the KMS properties table to CSVJani Nikula
Pandoc really did a bad job of converting the big KMS properties table to RST. Instead, put the properties into a separate plain text CSV file, and include it in the RST file. The generated output isn't very pretty, but at least the information is there, and it's stored in a format that's easier to process and improve upon at a later time. The CSV file was generated by copy-pasting the table from the HTML generated by the DocBook toolchain into LibreOffice Calc, and then saved as CSV, unmodified. Signed-off-by: Jani Nikula <jani.nikula@intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/17053ff08caf5cfac4f478437ef796f83a31d772.1466506505.git.jani.nikula@intel.com
2016-06-21Documentation/gpu: use recommended order of heading markersJani Nikula
While splitting the document up, the headings "shifted" from what pandoc generated. Use the following order for headings for consistency: ============== Document title ============== First ===== Second ------ Third ~~~~~ Leave the lower level headings as they are; I think those are less important. Although RST doesn't mandate a specific order ("Rather than imposing a fixed number and order of section title adornment styles, the order enforced will be the order as encountered."), having the higher levels the same overall makes it easier to follow the documents. [I'm sort of kind of writing the recommendation for docs-next in the mean time, but this order seems sensible, and is what I'm proposing.] Signed-off-by: Jani Nikula <jani.nikula@intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/126f42734defac6cbb8496a481d58db7b38461dd.1466506505.git.jani.nikula@intel.com
2016-06-21Documentation/gpu: split up the gpu documentationJani Nikula
Make the gpu documentation easier to manage by splitting to separate files. Again, this is just the split, no real edits. Signed-off-by: Jani Nikula <jani.nikula@intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/bd2b599b5105c28c8f05923005e6cc9b7efa7fc1.1466506505.git.jani.nikula@intel.com