kernel/linux.git/Documentation/gpu/todo.rst, branch v6.6.141

drm: Fix TODO list mentioning non-KMS drivers

2024-02-01T00:19:08+00:00

commit 9cf5ca1f485cae406968947a92bf304603999fa1 upstream. Non-KMS drivers have been removed from DRM. Update the TODO list accordingly. Signed-off-by: Thomas Zimmermann Fixes: a276afc19eec ("drm: Remove some obsolete drm pciids(tdfx, mga, i810, savage, r128, sis, via)") Cc: Cai Huoqing Cc: Daniel Vetter Cc: Dave Airlie Cc: Thomas Zimmermann Cc: Maarten Lankhorst Cc: Maxime Ripard Cc: David Airlie Cc: Daniel Vetter Cc: Jonathan Corbet Cc: dri-devel@lists.freedesktop.org Cc: # v6.3+ Cc: linux-doc@vger.kernel.org Reviewed-by: David Airlie Reviewed-by: Daniel Vetter Acked-by: Alex Deucher Link: https://patchwork.freedesktop.org/patch/msgid/20231122122449.11588-3-tzimmermann@suse.de Signed-off-by: Greg Kroah-Hartman

Merge tag 'docs-6.6' of git://git.lwn.net/linux

2023-08-31T03:05:42+00:00

Pull documentation updates from Jonathan Corbet: "Documentation work keeps chugging along; this includes: - Work from Carlos Bilbao to integrate rustdoc output into the generated HTML documentation. This took some work to figure out how to do it without slowing the docs build and without creating people who don't have Rust installed, but Carlos got there - Move the loongarch and mips architecture documentation under Documentation/arch/ - Some more maintainer documentation from Jakub ... plus the usual assortment of updates, translations, and fixes" * tag 'docs-6.6' of git://git.lwn.net/linux: (56 commits) Docu: genericirq.rst: fix irq-example input: docs: pxrc: remove reference to phoenix-sim Documentation: serial-console: Fix literal block marker docs/mm: remove references to hmm_mirror ops and clean typos docs/zh_CN: correct regi_chg(),regi_add() to region_chg(),region_add() Documentation: Fix typos Documentation/ABI: Fix typos scripts: kernel-doc: fix macro handling in enums scripts: kernel-doc: parse DEFINE_DMA_UNMAP_[ADDR|LEN] Documentation: riscv: Update boot image header since EFI stub is supported Documentation: riscv: Add early boot document Documentation: arm: Add bootargs to the table of added DT parameters docs: kernel-parameters: Refer to the correct bitmap function doc: update params of memhp_default_state= docs: Add book to process/kernel-docs.rst docs: sparse: fix invalid link addresses docs: vfs: clean up after the iterate() removal docs: Add a section on surveys to the researcher guidelines docs: move mips under arch docs: move loongarch under arch ...

Documentation: Fix typos

2023-08-18T17:29:03+00:00

Fix typos in Documentation. Signed-off-by: Bjorn Helgaas Link: https://lore.kernel.org/r/20230814212822.193684-4-helgaas@kernel.org Signed-off-by: Jonathan Corbet

drm/panel: Fix todo indentation for panel prepared/enabled cleanup

2023-08-03T08:21:27+00:00

In commit d2aacaf07395 ("drm/panel: Check for already prepared/enabled in drm_panel") the formatting for a code block was not quite right. This caused an error when building htmldocs: Documentation/gpu/todo.rst:469: ERROR: Unexpected indentation. Fix the error by using the proper syntax for a code block. Fixes: d2aacaf07395 ("drm/panel: Check for already prepared/enabled in drm_panel") Reported-by: Stephen Rothwell Closes: https://lore.kernel.org/r/20230802141724.0edce253@canb.auug.org.au Signed-off-by: Douglas Anderson Reviewed-by: Neil Armstrong Signed-off-by: Neil Armstrong Link: https://patchwork.freedesktop.org/patch/msgid/20230802074727.2.Iaeb7b0f7951aee6b8c090364bbc87b1ae198a857@changeid

drm/panel: Check for already prepared/enabled in drm_panel

2023-08-01T14:35:36+00:00

In a whole pile of panel drivers, we have code to make the prepare/unprepare/enable/disable callbacks behave as no-ops if they've already been called. It's silly to have this code duplicated everywhere. Add it to the core instead so that we can eventually delete it from all the drivers. Note: to get some idea of the duplicated code, try: git grep 'if.*>prepared' -- drivers/gpu/drm/panel git grep 'if.*>enabled' -- drivers/gpu/drm/panel NOTE: arguably, the right thing to do here is actually to skip this patch and simply remove all the extra checks from the individual drivers. Perhaps the checks were needed at some point in time in the past but maybe they no longer are? Certainly as we continue transitioning over to "panel_bridge" then we expect there to be much less variety in how these calls are made. When we're called as part of the bridge chain, things should be pretty simple. In fact, there was some discussion in the past about these checks [1], including a discussion about whether the checks were needed and whether the calls ought to be refcounted. At the time, I decided not to mess with it because it felt too risky. Looking closer at it now, I'm fairly certain that nothing in the existing codebase is expecting these calls to be refcounted. The only real question is whether someone is already doing something to ensure prepare()/unprepare() match and enabled()/disable() match. I would say that, even if there is something else ensuring that things match, there's enough complexity that adding an extra bool and an extra double-check here is a good idea. Let's add a drm_warn() to let people know that it's considered a minor error to take advantage of drm_panel's double-checking but we'll still make things work fine. We'll also add an entry to the official DRM todo list to remove the now pointless check from the panels after this patch lands and, eventually, fixup anyone who is triggering the new warning. [1] https://lore.kernel.org/r/20210416153909.v4.27.I502f2a92ddd36c3d28d014dd75e170c2d405a0a5@changeid Acked-by: Neil Armstrong Reviewed-by: Maxime Ripard Signed-off-by: Douglas Anderson Link: https://patchwork.freedesktop.org/patch/msgid/20230727101636.v4.2.I59b417d4c29151cc2eff053369ec4822b606f375@changeid

drm/todo: Convert list of fbconv links to footnotes

2023-07-29T19:25:15+00:00

Convert the references to fbconv links to footnotes, so they can be navigated. Signed-off-by: Geert Uytterhoeven Acked-by: Javier Martinez Canillas Signed-off-by: Javier Martinez Canillas Link: https://patchwork.freedesktop.org/patch/msgid/0761f98d3b6f8df9eea977eae063e35b450fda9e.1689779916.git.geert+renesas@glider.be

drm/todo: Add atomic modesetting references

2023-07-29T19:25:14+00:00

The section about converting existing KMS drivers to atomic modesetting mentions the existence of a conversion guide, but does not reference it. While the guide is old and rusty, it still contains useful information, so add a link to it. Also link to the LWN.net articles that give an overview about the atomic mode setting design. While at it, remove the reference to unconverted virtual HW drivers, as they've been converted. Signed-off-by: Geert Uytterhoeven Reviewed-by: Javier Martinez Canillas Reviewed-by: Laurent Pinchart Signed-off-by: Javier Martinez Canillas Link: https://patchwork.freedesktop.org/patch/msgid/6809d0fda0716892cbccf0ee272481032251026d.1689779916.git.geert+renesas@glider.be

fbdev: Make support for userspace interfaces configurable

2023-06-27T07:58:51+00:00

Add Kconfig option CONFIG_FB_DEVICE and make the virtual fbdev device optional. If the new option has not been selected, fbdev does not create files in devfs, sysfs or procfs. Most modern Linux systems run a DRM-based graphics stack that uses the kernel's framebuffer console, but has otherwise deprecated fbdev support. Yet fbdev userspace interfaces are still present. The option makes it possible to use the fbdev subsystem as console implementation without support for userspace. This closes potential entry points to manipulate kernel or I/O memory via framebuffers. It also prevents the execution of driver code via ioctl or sysfs, both of which might allow malicious software to exploit bugs in the fbdev code. A small number of fbdev drivers require struct fbinfo.dev to be initialized, usually for the support of sysfs interface. Make these drivers depend on FB_DEVICE. They can later be fixed if necessary. v3: * effect -> affect in Kconfig help (Daniel) v2: * set FB_DEVICE default to y (Geert) * comment on {get,put}_device() (Sam) * Kconfig fixes (Sam) * add TODO item about FB_DEVICE dependencies (Sam) Signed-off-by: Thomas Zimmermann Acked-by: Greg Kroah-Hartman Reviewed-by: Sam Ravnborg Link: https://patchwork.freedesktop.org/patch/msgid/20230613110953.24176-39-tzimmermann@suse.de

drm: Remove struct drm_driver.gem_prime_mmap

2023-06-19T11:56:40+00:00

All drivers initialize this field with drm_gem_prime_mmap(). Call the function directly and remove the field. Simplifies the code and resolves a long-standing TODO item. Signed-off-by: Thomas Zimmermann Reviewed-by: Alex Deucher Link: https://patchwork.freedesktop.org/patch/msgid/20230613150441.17720-3-tzimmermann@suse.de

drm/gem: Check for valid formats

2023-04-19T23:19:27+00:00

Currently, drm_gem_fb_create() doesn't check if the pixel format is supported, which can lead to the acceptance of invalid pixel formats e.g. the acceptance of invalid modifiers. Therefore, add a check for valid formats on drm_gem_fb_create(). Note that this check is only valid for atomic drivers, because, for non-atomic drivers, checking drm_any_plane_has_format() is not possible since the format list for the primary plane is fake, and we'd therefore reject valid formats. Adding this check to drm_gem_fb_create() will guarantee that the igt@kms_addfb_basic@addfb25-bad-modifier IGT test passes for drivers using this callback. This commit is a recapture of a series sent a while ago. Initially, I sent a patch [1] similar to this one in which I introduced the format check to drm_gem_fb_create(). Based on the feedback on the patch, I placed the check inside framebuffer_check() [2] so that it wouldn't be needed to hit any driver-specific code path when the check fails. Therefore, we could remove the check from the specific drivers (i915, amdgpu, and vmwgfx). But, with some new feedback, it was shown that introducing this check inside framebuffer_check() is problematic for the i915 driver [3]. For the i915 driver, in the legacy case, in which we don't get the modifier from the userspace, i915's fb_create hook computes the right modifier, which isn't necessarily linear. Therefore, if we check the modifier before that point, we might get wrong answers. So, I kept the check inside the i915 driver and removed the check from amdgpu and vmwgfx [4]. But, this yet hasn't solved the i915 problem [5]. As we cannot add the check inside framebuffer_check() without affecting the i915 behavior, this commit went back to the original patch. This way we can guarantee a more uniform behavior from the drivers that use the drm_gem_fb_create() callback. [1] https://lore.kernel.org/dri-devel/20230103125322.855089-1-mcanal@igalia.com/T/ [2] https://lore.kernel.org/dri-devel/20230109105807.18172-1-mcanal@igalia.com/T/ [3] https://lore.kernel.org/dri-devel/Y8AAdW2y7zN7DCUZ@intel.com/ [4] https://lore.kernel.org/dri-devel/20230113112743.188486-1-mcanal@igalia.com/T/ [5] https://lore.kernel.org/dri-devel/Y8FXWvEhO7GCRKVJ@intel.com/ Signed-off-by: Maíra Canal Reviewed-by: Ville Syrjälä Acked-by: Daniel Vetter Signed-off-by: Maíra Canal Link: https://patchwork.freedesktop.org/patch/msgid/20230412142923.136707-1-mcanal@igalia.com