linux/drivers/gpu
Mika Kuoppala ca6acc2525 drm/i915/gtt: Trust the uncached store to flush wcb
Not all architectures guarantee that uncached read will
flush the write combining buffer. So marking it explicitly
is recommended [1].

However we know the architecture we are operating on
and can avoid wmb as the UC store will flush the wcb [2].

Omit the wmb() before invalidate as redudant.

v2: squash combining and removal (Chris)
v3: remove obsolete comments about posting reads (Chris)

References: http://yarchive.net/comp/linux/write_combining.html [1]
References: http://download.intel.com/design/PentiumII/applnots/24442201.pdf [2]
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Matthew Auld <matthew.auld@intel.com>
Signed-off-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20180508124154.14586-1-mika.kuoppala@linux.intel.com
2018-05-11 15:52:21 +03:00
..
drm drm/i915/gtt: Trust the uncached store to flush wcb 2018-05-11 15:52:21 +03:00
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