Only sysfb drivers use drm_fb_build_fourcc_list(). Move the function
to sysfb helpers and rename it accordingly. Update drivers and tests.
v3:
- update naming in tests
v2:
- select DRM_SYSFB_HELPER (kernel test robot)
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: José Expósito <jose.exposito89@gmail.com>
Acked-by: Maxime Ripard <mripard@kernel.org>
Acked-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://lore.kernel.org/r/20250616083846.221396-4-tzimmermann@suse.de
Protect global edid_info behind CONFIG_FIRMWARE_EDID and remove
the config tests for CONFIG_X86. Makes edid_info available iff
its option has been enabled.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Helge Deller <deller@gmx.de>
Link: https://lore.kernel.org/r/20250602075537.137759-3-tzimmermann@suse.de
Share efidrm's and vesadrm's validation of struct screen_info in
shared helpers. Update the drivers.
Most validation helpers test individual values against limits and
can be shared as they are. For color formats, a common helper looks
up the correct DRM format info from a driver-provided list of color
formats.
These screen_info helpers are only available if CONFIG_SCREEN_INFO
has been selected, as done by efidrm and vesadrm.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://lore.kernel.org/r/20250410083834.10810-4-tzimmermann@suse.de
Provide sysfb helpers for validating framebuffer integer values
against limits. Update drivers. If a driver did not specify a limit
for a certain value, use INT_MAX.
v2:
- declare module information near EOF (Javier)
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://lore.kernel.org/r/20250410083834.10810-3-tzimmermann@suse.de
Clang warns (or errors with CONFIG_WERROR=y):
drivers/gpu/drm/sysfb/efidrm.c:353:11: error: variable 'screen_base' is used uninitialized whenever 'if' condition is false [-Werror,-Wsometimes-uninitialized]
353 | else if (mem_flags & EFI_MEMORY_WB)
| ^~~~~~~~~~~~~~~~~~~~~~~~~
drivers/gpu/drm/sysfb/efidrm.c:356:7: note: uninitialized use occurs here
356 | if (!screen_base)
| ^~~~~~~~~~~
drivers/gpu/drm/sysfb/efidrm.c:353:7: note: remove the 'if' if its condition is always true
353 | else if (mem_flags & EFI_MEMORY_WB)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
354 | screen_base = devm_memremap(&pdev->dev, mem->start, resource_size(mem),
drivers/gpu/drm/sysfb/efidrm.c:261:27: note: initialize the variable 'screen_base' to silence this warning
261 | void __iomem *screen_base;
| ^
| = NULL
efidrm_get_mem_flags() can only return a mask that has at least one of
the tested values set so the else case is impossible but clang's static
analysis runs before inlining so it cannot know that.
Initialize screen_base to NULL and add a defensive error message in case
mem_flags were ever returned without one of the four valid values.
Fixes: 32ae90c66f ("drm/sysfb: Add efidrm for EFI displays")
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://lore.kernel.org/r/20250410-efidrm-avoid-uninit-screen_info-warning-v2-1-b79646f58c24@kernel.org
Enable the connector's EDID property if edid_info contains valid
data. Exports the EDID via sysfs for user-space compositors.
EDID information is not always available. Depending on the system
and kernel configuration, it is either provided by the boot loader
or read by the kernel during early boot stages.
As of now, there's only one EFI display, so that EDID data always
belongs to this output. This might change if there's ever more than
one EFI display in the system.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://lore.kernel.org/r/20250401094056.32904-16-tzimmermann@suse.de
Add support for screen_info setups with VIDEO_TYPE_EFI. Provide the
minimum functionality of reading modes, updating and clearing the display.
There is existing support for these displays provided by simpledrm with
CONFIG_SYSFB_SIMPLEFB=y. Using efidrm over simpledrm will allows for the
mapping of video memory with correct caching. Simpledrm always assumes WC
caching, while fully cached memory is possible with efidrm. Efidrm will
also allow for the use of additional functionality provided by EFI, such
as EDID information.
In addition to efidrm, add struct pixel_format plus initializer macros.
The type and macros describe pixel formats in a generic way on order to
find the DRM format from the screen_info settings. Similar existing code
in SIMPLEFB_FORMATS and fbdev is not really what is needed in efidrm,
but SIMPLEFB_FORMATS can later be converted to struct pixel_format.
v4:
- depend on CONFIG_EFI
- disallow module for now as efi_mem_desc_lookup() is not exported
v3:
- depend on !SYSFB_SIMPLEFB (Javier)
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://lore.kernel.org/r/20250401094056.32904-15-tzimmermann@suse.de
