linux_dsm_epyc7002/drivers/gpu
Chris Wilson 900ccf30f9 drm/i915: Only force GGTT coherency w/a on required chipsets
Not all chipsets have an internal buffer delaying the visibility of
writes via the GGTT being visible by other physical paths, but we use a
very heavy workaround for all. We only need to apply that workarounds to
the chipsets we know suffer from the delay and the resulting coherency
issue.

Similarly, the same inconsistent coherency fouls up our ABI promise that
a write into a mmap_gtt is immediately visible to others. Since the HW
has made that a lie, let userspace know when that contract is broken.
(Not that userspace would want to use mmap_gtt on those chipsets for
other performance reasons...)

Testcase: igt/drv_selftest/live_coherency
Testcase: igt/gem_mmap_gtt/coherency
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=100587
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Tomasz Lis <tomasz.lis@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180720101910.11153-1-chris@chris-wilson.co.uk
2018-07-20 16:53:55 +01:00
..
drm drm/i915: Only force GGTT coherency w/a on required chipsets 2018-07-20 16:53:55 +01:00
host1x gpu: host1x: Use IOMMU groups 2017-12-21 14:52:36 +01:00
ipu-v3 gpu: ipu-v3: prg: avoid possible array underflow 2018-03-15 17:52:08 +01:00
vga vga_switcheroo: Let HDA autosuspend on mux change 2018-03-13 22:58:49 +01:00
Makefile