76a6d563db
On Xe-HP and later devices, dedicated compression control state (CCS) stored in local memory is used for each surface, to support the 3D and media compression formats. The memory required for the CCS of the entire local memory is 1/256 of the local memory size. So before the kernel boot, the required memory is reserved for the CCS data and a secure register will be programmed with the CCS base address So when an object is allocated in local memory, dont need to explicitly allocate the space for ccs data. But when the obj is evicted into the smem, to hold the compression related data along with the obj extra space is needed in smem. i.e obj_size + (obj_size/256). Hence when a smem pages are allocated for an obj with lmem placement possibility we create with the extra pages required for the ccs data for the obj size. v2: Used imperative wording [Thomas] v3: Inflate the pages only when obj's placement is lmem only v4: GEM_BUG_ON if the ttm->num_pages > obj page size [Thomas] Signed-off-by: Ramalingam C <ramalingam.c@intel.com> cc: Christian Koenig <christian.koenig@amd.com> cc: Hellstrom Thomas <thomas.hellstrom@intel.com> Reviewed-by: Thomas Hellstrom <thomas.hellstrom@linux.intel.com> Reviewed-by: Nirmoy Das <nirmoy.das@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20220405150840.29351-9-ramalingam.c@intel.com
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.
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.