b87d390196
As with EU masks, it's easier to store subslice/DSS masks internally in a format that's more natural for the driver to work with, and then only covert into the u8[] uapi form when the query ioctl is invoked. Since the hardware design changed significantly with Xe_HP, we'll use a union to choose between the old "hsw-style" subslice masks or the newer xehp mask. HSW-style masks will be stored in an array of u8's, indexed by slice (there's never more than 6 subslices per slice on older platforms). For Xe_HP and beyond where slices no longer exist, we only need a single bitmask. However we already know that this mask is eventually going to grow too large for a simple u64 to hold, so we'll represent it in a manner that can be operated on by the utilities in linux/bitmap.h. v2: - Fix typo: BIT(s) -> BIT(ss) in gen9_sseu_device_status() v3: - Eliminate sseu->ss_stride and just calculate the stride while specifically handling uapi. (Tvrtko) - Use BITMAP_BITS() macro to refer to size of masks rather than passing I915_MAX_SS_FUSE_BITS directly. (Tvrtko) - Report compute/geometry DSS masks separately when dumping Xe_HP SSEU info. (Tvrtko) - Restore dropped range checks to intel_sseu_has_subslice(). (Tvrtko) v4: - Make the bitmap size macro check the size of the .xehp field rather than the containing union. (Tvrtko) - Don't add GEM_BUG_ON() intel_sseu_has_subslice()'s check for whether slice or subslice ID exceed sseu->max_[sub]slices; various loops in the driver are expected to exceed these, so we should just silently return 'false.' v5: - Move XEHP_BITMAP_BITS() to the header so that we can also replace a usage of I915_MAX_SS_FUSE_BITS in one of the inline functions. (Bala) - Change the local variable in intel_slicemask_from_xehp_dssmask() from u16 to 'unsigned long' to make it a bit more future-proof. Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com> Cc: Balasubramani Vivekanandan <balasubramani.vivekanandan@intel.com> Signed-off-by: Matt Roper <matthew.d.roper@intel.com> Acked-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Reviewed-by: Balasubramani Vivekanandan <balasubramani.vivekanandan@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20220601150725.521468-6-matthew.d.roper@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.