drm/i915: Treat ringbuffer writes as write to normal memory
authorChris Wilson <chris@chris-wilson.co.uk>
Wed, 20 Jul 2016 12:31:55 +0000 (13:31 +0100)
committerChris Wilson <chris@chris-wilson.co.uk>
Wed, 20 Jul 2016 12:40:14 +0000 (13:40 +0100)
commit406ea8d22f9aeee6b484b35241ea5195c3af66a6
tree000e9299d7c55989538c73e2e7f03af064ce0ba2
parent34911fd30c6183036de67aa96e2c5a74cd43c9cf
drm/i915: Treat ringbuffer writes as write to normal memory

Ringbuffers are now being written to either through LLC or WC paths, so
treating them as simply iomem is no longer adequate. However, for the
older !llc hardware, the hardware is documentated as treating the TAIL
register update as serialising, so we can relax the barriers when filling
the rings (but even if it were not, it is still an uncached register write
and so serialising anyway.).

For simplicity, let's ignore the iomem annotation.

v2: Remove iomem from ringbuffer->virtual_address
v3: And for good measure add iomem elsewhere to keep sparse happy

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> #v2
Link: http://patchwork.freedesktop.org/patch/msgid/1469005202-9659-8-git-send-email-chris@chris-wilson.co.uk
Link: http://patchwork.freedesktop.org/patch/msgid/1469017917-15134-7-git-send-email-chris@chris-wilson.co.uk
drivers/gpu/drm/i915/i915_gem_gtt.c
drivers/gpu/drm/i915/i915_gem_gtt.h
drivers/gpu/drm/i915/i915_irq.c
drivers/gpu/drm/i915/intel_fbdev.c
drivers/gpu/drm/i915/intel_lrc.h
drivers/gpu/drm/i915/intel_ringbuffer.c
drivers/gpu/drm/i915/intel_ringbuffer.h