Alper Nebi Yasak ce3eb3c37b firmware: coreboot: framebuffer: Ignore reserved pixel color bits ... commit e6acaf25cb upstream. 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 <alpernebiyasak@gmail.com> Link: https://lore.kernel.org/r/20230122190433.195941-1-alpernebiyasak@gmail.com Cc: Salvatore Bonaccorso <carnil@debian.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2023-03-10 09:39:55 +01:00
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Kconfig	firmware: google: Properly state IOMEM dependency	2022-04-08 14:23:50 +02:00
Makefile	firmware: coreboot: Collapse platform drivers into bus core	2018-09-14 15:37:23 +02:00
coreboot_table.c	firmware: coreboot: Check size of table entry and use flex-array	2023-02-01 08:27:19 +01:00
coreboot_table.h	firmware: coreboot: Check size of table entry and use flex-array	2023-02-01 08:27:19 +01:00
framebuffer-coreboot.c	firmware: coreboot: framebuffer: Ignore reserved pixel color bits	2023-03-10 09:39:55 +01:00
gsmi.c	gsmi: fix null-deref in gsmi_get_variable	2023-01-24 07:22:47 +01:00
memconsole-coreboot.c	firmware: google: make coreboot driver's remove callback return void	2021-02-09 12:12:43 +01:00
memconsole-x86-legacy.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 287	2019-06-05 17:36:37 +02:00
memconsole.c	Merge 5.2-rc4 into char-misc-next	2019-06-09 09:11:21 +02:00
memconsole.h	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 287	2019-06-05 17:36:37 +02:00
vpd.c	firmware: google: make coreboot driver's remove callback return void	2021-02-09 12:12:43 +01:00
vpd_decode.c	firmware: google: increment VPD key_len properly	2019-10-11 08:41:34 +02:00
vpd_decode.h	firmware: google: check if size is valid when decoding VPD data	2019-09-04 13:31:28 +02:00