042bf75384
For some pixel formats .cpp structure in drm_format info it's not enough to describe the peculiarities of the pixel layout, for example tiled formats or packed formats at bit level. What's implemented here is to add three new members to drm_format_info that could describe such formats: - char_per_block[3] - block_w[3] - block_h[3] char_per_block will be put in a union alongside cpp, for transparent compatibility with the existing format descriptions. Regarding, block_w and block_h they are intended to be used through their equivalent getters drm_format_info_block_width / drm_format_info_block_height, the reason of the getters is to abstract the fact that for normal formats block_w and block_h will be unset/0, but the methods will be returning 1. Additionally, convenience function drm_format_info_min_pitch had been added that computes the minimum required pitch for a given pixel format and buffer width. Using that the following drm core functions had been updated to generically handle both block and non-block formats: - drm_fb_cma_get_gem_addr: for block formats it will just return the beginning of the block. - framebuffer_check: Use the newly added drm_format_info_min_pitch. - drm_gem_fb_create_with_funcs: Use the newly added drm_format_info_min_pitch. - In places where is not expecting to handle block formats, like fbdev helpers I just added some warnings in case the block width/height are greater than 1. Changes since v3: - Add helper function for computing the minimum required pitch. - Improve/cleanup documentation Changes since v8: - Fixed build on 32bits arm architectures, with: - return DIV_ROUND_UP((u64)buffer_width * info->char_per_block[plane], + return DIV_ROUND_UP_ULL((u64)buffer_width * info->char_per_block[plane], Reviewed-by: Brian Starkey <brian.starkey@arm.com> Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Alexandru Gheorghe <alexandru-cosmin.gheorghe@arm.com> Link: https://patchwork.freedesktop.org/patch/msgid/20181101170055.5433-1-alexandru-cosmin.gheorghe@arm.com |
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| Documentation | ||
| LICENSES | ||
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| drivers | ||
| firmware | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
README
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.