Chris Wilson a8bd3b884d drm/i915: Flush chipset caches after GGTT writes ... Our I915g (early gen3, the oldest machine we have in the farm) is still reporting occasional incoherency performing the following operations: 1) write through GGTT (indirect write into memory) 2) write through either CPU or WC (direct write into memory) 3) read from GGTT (indirect read) Instead of reporting the value from (2), the read from GGTT reports the earlier value written via the GGTT. We have made sure that the writes are flushed from the CPU (commit 3a32497f0d ("drm/i915/selftests: Provide full mb() around clflush") and commit add00e6d89 ("drm/i915: Flush the WCB following a WC write")), but still see the error, just less frequently. The only remaining cache that might be affected here is a chipset cache, so flush that as well. Testcase: igt/drv_selftest/live_coherency #gdg Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20180717092655.28417-1-chris@chris-wilson.co.uk		2018-07-17 17:32:52 +01:00
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drm	drm/i915: Flush chipset caches after GGTT writes	2018-07-17 17:32:52 +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
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