drm/i915/gt: Ignore irq enabling on the virtual engines

We do not use the virtual engines for interrupts (they have physical
components), but we do use them to decouple the fence signaling during
submission. Currently, when we submit a completed request, we try to
enable the interrupt handler for the virtual engine, but we never disarm
it. A quick fix is then to mark the irq as enabled, and it will then
remain enabled -- and this prevents us from waking the device and never
letting it sleep again.

Fixes: f8db4d051b5e ("drm/i915: Initialise breadcrumb lists on the virtual engine")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: <stable@vger.kernel.org> # v5.5+
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200711203236.12330-1-chris@chris-wilson.co.uk
(cherry picked from commit 4fe6abb8f51355224808ab02a9febf65d184c40b)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

diff --git a/drivers/gpu/drm/i915/gt/intel_lrc.c b/drivers/gpu/drm/i915/gt/intel_lrc.c
index 7c3d8ef4a47ce7ad43b13987de2bb491b8149ba6..d270d2db6f0a8245e0bcb06a877b60d929e67e16 100644 (file)
--- a/drivers/gpu/drm/i915/gt/intel_lrc.c
+++ b/drivers/gpu/drm/i915/gt/intel_lrc.c
@@ -5688,6 +5688,7 @@ intel_execlists_create_virtual(struct intel_engine_cs **siblings,
        intel_engine_init_active(&ve->base, ENGINE_VIRTUAL);
        intel_engine_init_breadcrumbs(&ve->base);
        intel_engine_init_execlists(&ve->base);
+       ve->base.breadcrumbs.irq_armed = true; /* fake HW, used for irq_work */
 
        ve->base.cops = &virtual_context_ops;
        ve->base.request_alloc = execlists_request_alloc;