Imre Deak 0cb5670baa drm/i915: Make sure engines are idle during GPU idling in LR mode ... We assume that the GPU is idle once receiving the seqno via the last request's user interrupt. In execlist mode the corresponding context completed interrupt can be delayed though and until this latter interrupt arrives we consider the request to be pending on the ELSP submit port. This can cause a problem during system suspend where this last request will be seen by the resume code as still pending. Such pending requests are normally replayed after a GPU reset, but during resume we reset both SW and HW tracking of the ring head/tail pointers, so replaying the pending request with its stale tail pointer will leave the ring in an inconsistent state. A subsequent request submission can lead then to the GPU executing from uninitialized area in the ring behind the above stale tail pointer. Fix this by making sure any pending request on the ELSP port is completed before suspending. I used a polling wait since the completion time I measured was <1ms and since normally we only need to wait during system suspend. GPU idling during runtime suspend is scheduled with a delay (currently 50-100ms) after the retirement of the last request at which point the context completed interrupt must have arrived already. The chance of this bug was increased by commit 1c777c5d1d Author: Imre Deak <imre.deak@intel.com> Date: Wed Oct 12 17:46:37 2016 +0300 drm/i915/hsw: Fix GPU hang during resume from S3-devices state but it could happen even without the explicit GPU reset, since we disable interrupts afterwards during the suspend sequence. v2: - Do an unlocked poll-wait first. (Chris) v3-4: - s/intel_lr_engines_idle/intel_execlists_idle/ and move i915.enable_execlists check to the new helper. (Chris) Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Mika Kuoppala <mika.kuoppala@intel.com> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=98470 Signed-off-by: Imre Deak <imre.deak@intel.com> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Link: http://patchwork.freedesktop.org/patch/msgid/1478510405-11799-3-git-send-email-imre.deak@intel.com		2016-11-07 14:48:05 +02:00
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drm	drm/i915: Make sure engines are idle during GPU idling in LR mode	2016-11-07 14:48:05 +02:00
host1x
ipu-v3	gpu: Remove depends on RESET_CONTROLLER when not a provider	2016-10-19 09:26:15 +02:00
vga	drivers/gpu/vga: allocate vga_arb_write() buffer on stack	2016-10-17 08:21:14 +02:00
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