external/libdrm
Revision | 5d97031e8aa717c83993fcdaa45b0812ddceb3b0 (tree) |
---|---|
Time | 2021-06-22 20:16:04 |
Author | Marius Vlad <marius.vlad@coll...> |
Commiter | Daniel Stone |
README.rst: Include some notes about syncing uapi headers
Signed-off-by: Marius Vlad <marius.vlad@collabora.com>
@@ -13,6 +13,24 @@ but a new libdrm will always work with an older kernel. | ||
13 | 13 | libdrm is a low-level library, typically used by graphics drivers such as |
14 | 14 | the Mesa drivers, the X drivers, libva and similar projects. |
15 | 15 | |
16 | +Syncing with the Linux kernel headers | |
17 | +------------------------------------- | |
18 | + | |
19 | +The library should be regularly updated to match the recent changes in the | |
20 | +`include/uapi/drm/`. | |
21 | + | |
22 | +libdrm maintains a human-readable version for the token format modifier, with | |
23 | +the simpler ones being extracted automatically from `drm_fourcc.h` header file | |
24 | +with the help of a python script. This might not always possible, as some of | |
25 | +the vendors require decoding/extracting them programmatically. For that | |
26 | +reason one can enhance the current vendor functions to include/provide the | |
27 | +newly added token formats, or, in case there's no such decoding | |
28 | +function, to add one that performs the tasks of extracting them. | |
29 | + | |
30 | +For simpler format modifier tokens there's a script (gen_table_fourcc.py) that | |
31 | +creates a static table, by going over `drm_fourcc.h` header file. The script | |
32 | +could be further modified if it can't handle new (simpler) token format | |
33 | +modifiers instead of the generated static table. | |
16 | 34 | |
17 | 35 | Compiling |
18 | 36 | --------- |