On Wed, Jun 30, 2021 at 4:18 PM Thomas Zimmermann tzimmermann@suse.de wrote:
Hi
Am 30.06.21 um 12:49 schrieb Daniel Vetter:
On Wed, Jun 30, 2021 at 11:52:27AM +0200, Thomas Zimmermann wrote:
The code in xcs_resume() probably didn't work as intended. It uses struct drm_device.irq, which is allocated to 0, but never initialized by i915 to the device's interrupt number.
v3: * also use intel_synchronize_hardirq() at another callsite v2: * wrap irq code in intel_synchronize_hardirq() (Ville)
Signed-off-by: Thomas Zimmermann tzimmermann@suse.de Fixes: 536f77b1caa0 ("drm/i915/gt: Call stop_ring() from ring resume, again") Cc: Chris Wilson chris@chris-wilson.co.uk Cc: Mika Kuoppala mika.kuoppala@linux.intel.com Cc: Daniel Vetter daniel.vetter@ffwll.ch Cc: Rodrigo Vivi rodrigo.vivi@intel.com Cc: Joonas Lahtinen joonas.lahtinen@linux.intel.com Cc: Maarten Lankhorst maarten.lankhorst@linux.intel.com Cc: Lucas De Marchi lucas.demarchi@intel.com
drivers/gpu/drm/i915/gt/intel_engine_cs.c | 2 +- drivers/gpu/drm/i915/gt/intel_ring_submission.c | 2 +- drivers/gpu/drm/i915/i915_irq.c | 5 +++++ drivers/gpu/drm/i915/i915_irq.h | 1 + 4 files changed, 8 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/i915/gt/intel_engine_cs.c b/drivers/gpu/drm/i915/gt/intel_engine_cs.c index 88694822716a..5ca3d1664335 100644 --- a/drivers/gpu/drm/i915/gt/intel_engine_cs.c +++ b/drivers/gpu/drm/i915/gt/intel_engine_cs.c @@ -1229,7 +1229,7 @@ bool intel_engine_is_idle(struct intel_engine_cs *engine) return true;
/* Waiting to drain ELSP? */
- synchronize_hardirq(to_pci_dev(engine->i915->drm.dev)->irq);
intel_synchronize_hardirq(engine->i915); intel_engine_flush_submission(engine);
/* ELSP is empty, but there are ready requests? E.g. after reset */
diff --git a/drivers/gpu/drm/i915/gt/intel_ring_submission.c b/drivers/gpu/drm/i915/gt/intel_ring_submission.c index 5d42a12ef3d6..1b5a22a83db6 100644 --- a/drivers/gpu/drm/i915/gt/intel_ring_submission.c +++ b/drivers/gpu/drm/i915/gt/intel_ring_submission.c @@ -185,7 +185,7 @@ static int xcs_resume(struct intel_engine_cs *engine) ring->head, ring->tail);
/* Double check the ring is empty & disabled before we resume */
- synchronize_hardirq(engine->i915->drm.irq);
- intel_synchronize_hardirq(engine->i915); if (!stop_ring(engine)) goto err;
diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c index 7d0ce8b9f8ed..2203dca19895 100644 --- a/drivers/gpu/drm/i915/i915_irq.c +++ b/drivers/gpu/drm/i915/i915_irq.c @@ -4575,3 +4575,8 @@ void intel_synchronize_irq(struct drm_i915_private *i915) { synchronize_irq(to_pci_dev(i915->drm.dev)->irq); }
+void intel_synchronize_hardirq(struct drm_i915_private *i915) +{
- synchronize_hardirq(to_pci_dev(i915->drm.dev)->irq);
I honestly think the hardirq here is about as much cargo-culted as using the wrong irq number.
I'd just use intel_synchronize_irq in both places and see whether CI complains, then go with that.
Well, ok. I don't think I have Sandybridge HW available. Would the Intel CI infrastructure catch any problems with such a change?
If there's anything obvious busted with it it should catch it (like if we end up calling synchronize_irq from softirq context, where only synchronize_hardirq is allowed, but I don't think that's the case).
And if I'm wrong we know what kind of comment to put there to explain why things are different. -Daniel
Best regards Thomas
-Daniel
+} diff --git a/drivers/gpu/drm/i915/i915_irq.h b/drivers/gpu/drm/i915/i915_irq.h index db34d5dbe402..e43b6734f21b 100644 --- a/drivers/gpu/drm/i915/i915_irq.h +++ b/drivers/gpu/drm/i915/i915_irq.h @@ -94,6 +94,7 @@ void intel_runtime_pm_disable_interrupts(struct drm_i915_private *dev_priv); void intel_runtime_pm_enable_interrupts(struct drm_i915_private *dev_priv); bool intel_irqs_enabled(struct drm_i915_private *dev_priv); void intel_synchronize_irq(struct drm_i915_private *i915); +void intel_synchronize_hardirq(struct drm_i915_private *i915);
int intel_get_crtc_scanline(struct intel_crtc *crtc); void gen8_irq_power_well_post_enable(struct drm_i915_private *dev_priv, -- 2.32.0
-- Thomas Zimmermann Graphics Driver Developer SUSE Software Solutions Germany GmbH Maxfeldstr. 5, 90409 Nürnberg, Germany (HRB 36809, AG Nürnberg) Geschäftsführer: Felix Imendörffer