Only set PMI fields if the screen_info's Vesa PM segment has been
set. Vesa PMI is the power-management interface. It also provides
means to set the color palette. The interface is optional, so not
all VESA graphics cards support it. Print vesafb's warning [1] if
the hardware palette cannot be set at all.
If unsupported the field PrimaryPalette in struct vesadrm.pmi is
NULL, which results in a segmentation fault. Happens with qemu's
Cirrus emulation.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Fixes: 814d270b31 ("drm/sysfb: vesadrm: Add gamma correction")
Link: https://elixir.bootlin.com/linux/v6.15/source/drivers/video/fbdev/vesafb.c#L375 # 1
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Javier Martinez Canillas <javierm@redhat.com>
Cc: dri-devel@lists.freedesktop.org
Acked-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://lore.kernel.org/r/20250617140944.142392-1-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
Split drm_sysfb_helper.c into two source files. There's now one
source file for the mode-setting pipeline and one source file for
module meta data. Prepares for adding additional source code to
sysfb helpers.
v2:
- fix typo in commit message (Javier)
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://lore.kernel.org/r/20250410083834.10810-2-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
The res pointer passed to simpledrm_device_release_clocks() and
simpledrm_device_release_regulators() points to an instance of
struct simpledrm_device. No need to upcast from struct drm_device.
The upcast is harmless, as DRM device is the first field in struct
simpledrm_device.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Fixes: 11e8f5fd22 ("drm: Add simpledrm driver")
Cc: <stable@vger.kernel.org> # v5.14+
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Jocelyn Falempe <jfalempe@redhat.com>
Link: https://lore.kernel.org/r/20250407134753.985925-2-tzimmermann@suse.de
Add palette support and export GAMMA properties via sysfs. User-space
compositors can use this interface for programming gamma ramps or night
mode.
Vesadrm supports palette updates via VGA DAC registers or VESA palette
calls. Up to 256 palette entries are available. Userspace always supplies
gamma ramps of 256 entries. If the native color format does not match
this because pixel component have less then 8 bits, vesadrm interpolates
among the palette entries.
The code uses CamelCase style in a few places to match the VESA manuals.
v3:
- fix coding style
v2:
- use CONFIG_X86_32 instead of __i386__ (checkpatch)
- protect struct vesadrm.pmi with CONFIG_X86_32
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://lore.kernel.org/r/20250401094056.32904-19-tzimmermann@suse.de
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.
There's only one VESA display, so EDID data always belongs to this
output.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://lore.kernel.org/r/20250401094056.32904-18-tzimmermann@suse.de
Add support for screen_info setups with VIDEO_TYPE_VLFB. 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 vesadrm over simpledrm will allow for the
use of additional functionality provided by VESA, such as EDID information,
gamma correction and palette modes. This enhances the user experience and
adds support for more display configuratons.
v4:
- depend on CONFIG_X86
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/20250401094056.32904-17-tzimmermann@suse.de
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
Add EDID support to sysfb connector helpers. Read the EDID property
from the OF node in ofdrm. Without EDID, this does nothing.
Some systems with OF display, such as 32-bit PPC Macintoshs, provide
the system display's EDID data as node property in their DT. Exporting
this information allows compositors to implement correct DPI and
meaningful color management.
v3:
- avoid parser error by clearing EDID extension field
v2:
- return errno codes on errors (Jani)
- simplify EDID read logic (Jani)
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://lore.kernel.org/r/20250401094056.32904-13-tzimmermann@suse.de
Merge the primary plane code of ofdrm and simpledrm. Replace the
plane implementation in each driver with the shared helpers. Set
up driver callbacks and format modifiers with initializer macros.
The plane code in ofdrm and simpledrm is very similar. Ofdrm has a
more sophisticated implementation of atomic_disable, which clears
individual scanlines. The code in simpledrm clears the whole buffer
at once. Take the ofdrm version.
Simpledrm supports get_scanout_buffer. Import it into the shared
helpers, which makes it available in ofdrm.
The supported formats are all native formats plus an optional enulated
XRGB8888 if that's not already a native format. Provide an initializer
macro that computes the size of the formats array.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://lore.kernel.org/r/20250401094056.32904-12-tzimmermann@suse.de
Merge the CRTC functions of ofdrm and simpledrm. Replace the code
in each driver with the shared helpers. Set up callbacks with
initializer macros.
Ofdrm supports a gamma LUT, while simpledrm does not. So far ofdrm's
LUT size has been hard-coded in the driver CRTC's atomic_check helper.
Now pass the size of the LUT to the sysfb device. Ofdrm's custom
atomic_flush is still required to apply changes to the LUT. Simpledrm
passes a LUT size of 0, which disables the gamma LUT.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://lore.kernel.org/r/20250401094056.32904-11-tzimmermann@suse.de
Move ofdrm's struct ofdrm_crtc_state plus functions to sysfb
helpers and rename everything to drm_sysfb_crtc_state.
The sysfb CRTC state is a regular CRTC state with information on
the primary plane's color format, as required for color management.
Helpers for sysfb planes will later set this up automatically.
In ofdrm and simpledrm, replace existing code with the new helpers.
Ofdrm continues to use the CRTC state for color management. This
has no effect on simpledrm.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://lore.kernel.org/r/20250401094056.32904-10-tzimmermann@suse.de
Merge the connector functions of ofdrm and simpledrm. Replace the
code in each driver with the shared helpers. Set up callbacks with
initializer macros.
No effective code changes. The sysfb connector only returns the
preconfigured display mode.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://lore.kernel.org/r/20250401094056.32904-9-tzimmermann@suse.de
Provide initializer to set struct drm_mode_config_funcs. Convert
ofdrm and simpledrm.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://lore.kernel.org/r/20250401094056.32904-8-tzimmermann@suse.de
Merge the mode-init functions of ofdrm and simpledrm to the new helper
drm_sysfb_mode(). Also implement the DPI defaults there. Replace the
code in each driver with the shared helper.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://lore.kernel.org/r/20250401094056.32904-7-tzimmermann@suse.de
Add struct drm_sysfb_device that stores the system display's hardware
settings. Further helpers for the mode-setting pipeline will use these
fields. Convert ofdrm and simpledrm by embedding the sysfb device in
their device structs.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://lore.kernel.org/r/20250401094056.32904-6-tzimmermann@suse.de
The ofdrm and simpledrm drivers are special as they operate on
externally provided framebuffers. Move them into their own sub-
directory. Will let them share common code.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://lore.kernel.org/r/20250401094056.32904-5-tzimmermann@suse.de
