[Intel-gfx] [PATCH v2] drm/i915/gt: Sanitize and reset GPU before removing powercontext

[Chris Wilson]

Quoting Ville Syrjälä (2020-01-13 14:09:23)
> On Mon, Jan 13, 2020 at 01:29:56PM +0000, Chris Wilson wrote:
> > As a final paranoid step (we _should_ have reset the GPU on suspending
> > the device prior to unload), reset the GPU once more before removing the
> > powercontext and other related power saving paraphernalia.
> > 
> > A clue that this may not be the case is
> > 
> > <7> [313.203721] __intel_gt_set_wedged rcs'0
> > <7> [313.203746] __intel_gt_set_wedged        Awake? 3
> > <7> [313.203751] __intel_gt_set_wedged        Barriers?: no
> > <7> [313.203756] __intel_gt_set_wedged        Latency: 0us
> > <7> [313.203762] __intel_gt_set_wedged        Reset count: 0 (global 0)
> > <7> [313.203766] __intel_gt_set_wedged        Requests:
> > <7> [313.203785] __intel_gt_set_wedged        MMIO base:  0x00002000
> > <7> [313.203819] __intel_gt_set_wedged        RING_START: 0x00000000
> > <7> [313.203826] __intel_gt_set_wedged        RING_HEAD:  0x00000000
> > <7> [313.203833] __intel_gt_set_wedged        RING_TAIL:  0x00000000
> > <7> [313.203844] __intel_gt_set_wedged        RING_CTL:   0x00000000
> > <7> [313.203854] __intel_gt_set_wedged        RING_MODE:  0x00000000
> > <7> [313.203861] __intel_gt_set_wedged        RING_IMR: fffffefe
> > <7> [313.203875] __intel_gt_set_wedged        ACTHD:  0x00000000_00000000
> > <7> [313.203888] __intel_gt_set_wedged        BBADDR: 0x00000000_00000000
> > <7> [313.203901] __intel_gt_set_wedged        DMA_FADDR: 0x00000000_00000000
> > <7> [313.203909] __intel_gt_set_wedged        IPEIR: 0x00000000
> > <7> [313.203916] __intel_gt_set_wedged        IPEHR: 0xcccccccc
> > <7> [313.203921] __intel_gt_set_wedged        Execlist tasklet queued? no (enabled), preempt? inactive, timeslice? inactive
> > <7> [313.203932] __intel_gt_set_wedged        Execlist status: 0x00044032 00000020; CSB read:5, write:0, entries:6
> > <7> [313.203937] __intel_gt_set_wedged        Execlist CSB[0]: 0x00000001, context: 0
> > <7> [313.203952] __intel_gt_set_wedged                Pending[0] ring:{start:000c4000, hwsp:fedfc000, seqno:00000000}, rq:  402e:2-  prio=2147483647 @ 207ms: [i915]
> > <7> [313.203983] __intel_gt_set_wedged                E  402e:2-  prio=2147483647 @ 207ms: [i915]
> > <7> [313.204006] __intel_gt_set_wedged                Queue priority hint: 3
> > 
> > during rapid fault-injection reloads. 0xcc is POISON_FREE_INIT which
> > suggests that the system cleared the pages on initialisation as they are
> > still being used from the previous module load.
> > 
> > Despite that we also have a couple of GPU resets prior to this...
> > I have a sneaky suspicion that may be a GuC artifact.
> > 
> > Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> > Cc: Andi Shyti <andi.shyti at intel.com>
> > Cc: Mika Kuoppala <mika.kuoppala at linux.intel.com>
> > 
> > drm/i915/gt: Lift clearing GT wedged out of gt_sanitize
> > 
> > We only want to try and reset a wedged device on resume, not before
> > suspend, so lift the recovery out of the commont gt_sanitize().
> > 
> > Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> > Cc: Andi Shyti <andi.shyti at intel.com>
> > Cc: Mika Kuoppala <mika.kuoppala at linux.intel.com>
> > ---
> >  drivers/gpu/drm/i915/gt/intel_gt_pm.c | 56 +++++++++++----------------
> >  1 file changed, 22 insertions(+), 34 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/i915/gt/intel_gt_pm.c b/drivers/gpu/drm/i915/gt/intel_gt_pm.c
> > index d1c2f034296a..09a78d767e24 100644
> > --- a/drivers/gpu/drm/i915/gt/intel_gt_pm.c
> > +++ b/drivers/gpu/drm/i915/gt/intel_gt_pm.c
> > @@ -118,36 +118,16 @@ void intel_gt_pm_init(struct intel_gt *gt)
> >       intel_rps_init(&gt->rps);
> >  }
> >  
> > -static bool reset_engines(struct intel_gt *gt)
> > +static void reset_engines(struct intel_gt *gt)
> >  {
> >       if (INTEL_INFO(gt->i915)->gpu_reset_clobbers_display)
> 
> Should that be a !gpu_reset_clobbers_display now?

Heh. Yes. Far too many mistakes today.
-Chris