firmware: coreboot: Don't register a pdev if screen_info data is present

On coreboot platforms, a system framebuffer may be provided to the Linux
kernel by filling a LB_TAG_FRAMEBUFFER entry in the

firmware: coreboot: Don't register a pdev if screen_info data is present

On coreboot platforms, a system framebuffer may be provided to the Linux
kernel by filling a LB_TAG_FRAMEBUFFER entry in the coreboot table. But
a coreboot payload (e.g: SeaBIOS) could also provide its own framebuffer
information to the Linux kernel.

If that's the case, arch x86 boot code will fill the global screen_info
data and this used by the Generic System Framebuffers (sysfb) framework,
to register a platform device with pdata about the system's framebuffer.

But later, the framebuffer_coreboot driver will try to do the same and
attempt to register a "simple-framebuffer" platform device (using the
information from the coreboot table), which will lead to an error due a
device with the same name already being registered:

sysfs: cannot create duplicate filename '/bus/platform/devices/simple-framebuffer.0'
...
coreboot: could not register framebuffer
framebuffer coreboot8: probe with driver framebuffer failed with error -17

To prevent this issue, make the framebuffer_core driver to not register
a platform device if the global struct screen_info data has been filled.

Reported-by: Brian Norris <[email protected]>
Closes: https://lore.kernel.org/all/ZuCG-DggNThuF4pj@b20ea791c01f/T/#ma7fb65acbc1a56042258adac910992bb225a20d2
Suggested-by: Julius Werner <[email protected]>
Signed-off-by: Javier Martinez Canillas <[email protected]>
Reviewed-by: Thomas Zimmermann <[email protected]>
Reviewed-by: Brian Norris <[email protected]>
Reviewed-by: Julius Werner <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Tzung-Bi Shih <[email protected]>

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firmware: google: add missing MODULE_DESCRIPTION() macros

make allmodconfig && make W=1 C=1 reports:
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/firmware/google/gsmi.o
WARNING: modpost

firmware: google: add missing MODULE_DESCRIPTION() macros

make allmodconfig && make W=1 C=1 reports:
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/firmware/google/gsmi.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/firmware/google/coreboot_table.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/firmware/google/framebuffer-coreboot.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/firmware/google/memconsole.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/firmware/google/memconsole-coreboot.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/firmware/google/memconsole-x86-legacy.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/firmware/google/cbmem.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/firmware/google/vpd-sysfs.o

Add the missing invocations of the MODULE_DESCRIPTION() macro.

Signed-off-by: Jeff Johnson <[email protected]>
Link: https://lore.kernel.org/r/20240605-md-drivers-firmware-google-v1-1-18878de97fa5@quicinc.com
Signed-off-by: Tzung-Bi Shih <[email protected]>

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firmware: coreboot: Replace tag with id table in driver struct

Switch the plain 'tag' field in struct coreboot_driver for the newly
created coreboot_device_id struct, which also contains a tag field

firmware: coreboot: Replace tag with id table in driver struct

Switch the plain 'tag' field in struct coreboot_driver for the newly
created coreboot_device_id struct, which also contains a tag field and
has the benefit of allowing modalias generation, and update all coreboot
drivers accordingly.

While at it, also add the id table for each driver to the module device
table to allow automatically loading the module.

Reviewed-by: AngeloGioacchino Del Regno <[email protected]>
Reviewed-by: Brian Norris <[email protected]>
Signed-off-by: Nícolas F. R. A. Prado <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Tzung-Bi Shih <[email protected]>

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firmware: coreboot: framebuffer: Avoid invalid zero physical address

On ARM64 systems coreboot defers framebuffer allocation to its payload,
to be done by a libpayload function call. In this case, c

firmware: coreboot: framebuffer: Avoid invalid zero physical address

On ARM64 systems coreboot defers framebuffer allocation to its payload,
to be done by a libpayload function call. In this case, coreboot tables
still include a framebuffer entry with display format details, but the
physical address field is set to zero (as in [1], for example).

Unfortunately, this field is not automatically updated when the
framebuffer is initialized through libpayload, citing that doing so
would invalidate checksums over the entire coreboot table [2].

This can be observed on ARM64 Chromebooks with stock firmware. On a
Google Kevin (RK3399), trying to use coreboot framebuffer driver as
built-in to the kernel results in a benign error. But on Google Hana
(MT8173) and Google Cozmo (MT8183) it causes a hang.

When the framebuffer physical address field in the coreboot table is
zero, we have no idea where coreboot initialized a framebuffer, or even
if it did. Instead of trying to set up a framebuffer located at zero,
return ENODEV to indicate that there isn't one.

[1] https://review.coreboot.org/c/coreboot/+/17109
[2] https://review.coreboot.org/c/coreboot/+/8797

Signed-off-by: Alper Nebi Yasak <[email protected]>
Reviewed-by: Julius Werner <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Tzung-Bi Shih <[email protected]>

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firmware: coreboot: framebuffer: Ignore reserved pixel color bits

The coreboot framebuffer doesn't support transparency, its 'reserved'
bit field is merely padding for byte/word alignment of pixel c

firmware: coreboot: framebuffer: Ignore reserved pixel color bits

The coreboot framebuffer doesn't support transparency, its 'reserved'
bit field is merely padding for byte/word alignment of pixel colors [1].
When trying to match the framebuffer to a simplefb format, the kernel
driver unnecessarily requires the format's transparency bit field to
exactly match this padding, even if the former is zero-width.

Due to a coreboot bug [2] (fixed upstream), some boards misreport the
reserved field's size as equal to its position (0x18 for both on a
'Lick' Chromebook), and the driver fails to probe where it would have
otherwise worked fine with e.g. the a8r8g8b8 or x8r8g8b8 formats.

Remove the transparency comparison with reserved bits. When the
bits-per-pixel and other color components match, transparency will
already be in a subset of the reserved field. Not forcing it to match
reserved bits allows the driver to work on the boards which misreport
the reserved field. It also enables using simplefb formats that don't
have transparency bits, although this doesn't currently happen due to
format support and ordering in linux/platform_data/simplefb.h.

[1] https://review.coreboot.org/plugins/gitiles/coreboot/+/4.19/src/commonlib/include/commonlib/coreboot_tables.h#255
[2] https://review.coreboot.org/plugins/gitiles/coreboot/+/4.13/src/drivers/intel/fsp2_0/graphics.c#82

Signed-off-by: Alper Nebi Yasak <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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firmware: google: make coreboot driver's remove callback return void

All coreboot drivers return 0 unconditionally in their remove callback.
Also the device core ignores the return value of the stru

firmware: google: make coreboot driver's remove callback return void

All coreboot drivers return 0 unconditionally in their remove callback.
Also the device core ignores the return value of the struct
bus_type::remove(), so make the coreboot remove callback return void
instead of giving driver authors the illusion they could return an error
code here.

All drivers are adapted accordingly.

Signed-off-by: Uwe Kleine-König <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 287

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of th

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 287

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license v2 0 as
published by the free software foundation this program is
distributed in the hope that it will be useful but without any
warranty without even the implied warranty of merchantability or
fitness for a particular purpose see the gnu general public license
for more details

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 23 file(s).

Signed-off-by: Thomas Gleixner <[email protected]>
Reviewed-by: Alexios Zavras <[email protected]>
Reviewed-by: Allison Randal <[email protected]>
Cc: [email protected]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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firmware: google: Add a module_coreboot_driver() macro and use it

Remove some boiler plate code we have in three drivers with a single
line each time. This also gets us a free assignment of the driv

firmware: google: Add a module_coreboot_driver() macro and use it

Remove some boiler plate code we have in three drivers with a single
line each time. This also gets us a free assignment of the driver .owner
field, making these drivers work better as modules.

Cc: Wei-Ning Huang <[email protected]>
Cc: Julius Werner <[email protected]>
Cc: Brian Norris <[email protected]>
Cc: Samuel Holland <[email protected]>
Cc: Guenter Roeck <[email protected]>
Signed-off-by: Stephen Boyd <[email protected]>
Reviewed-by: Julius Werner <[email protected]>
Reviewed-by: Samuel Holland <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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firmware: coreboot: Add coreboot framebuffer driver

Register a simplefb framebuffer when the coreboot table contains a
framebuffer entry.

Signed-off-by: Samuel Holland <[email protected]>
Signed-

firmware: coreboot: Add coreboot framebuffer driver

Register a simplefb framebuffer when the coreboot table contains a
framebuffer entry.

Signed-off-by: Samuel Holland <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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