Commit 0da3f250 authored by Chris Wilson's avatar Chris Wilson
Browse files

drm/i915/gt: Disable arbitration around Braswell's pdp updates 



Braswell's pdp workaround is full of dragons, that may be being angered
when they are interrupted. Let's not take that risk and disable
arbitration during the update.

Signed-off-by: default avatarChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: default avatarTvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210111105735.21515-1-chris@chris-wilson.co.uk
parent 6a3daee1

drivers/gpu/drm/i915/gt/intel_execlists_submission.c

+10 −1
Original line number Diff line number Diff line
@@ -2539,6 +2539,14 @@ static int emit_pdps(struct i915_request *rq) 
	 * GPU hangs to forcewake errors and machine lockups!

	 */



	cs = intel_ring_begin(rq, 2);

	if (IS_ERR(cs))

		return PTR_ERR(cs);



	*cs++ = MI_ARB_ON_OFF | MI_ARB_DISABLE;

	*cs++ = MI_NOOP;

	intel_ring_advance(rq, cs);



	/* Flush any residual operations from the context load */

	err = engine->emit_flush(rq, EMIT_FLUSH);

	if (err)
@@ -2564,7 +2572,8 @@ static int emit_pdps(struct i915_request *rq) 
		*cs++ = i915_mmio_reg_offset(GEN8_RING_PDP_LDW(base, i));

		*cs++ = lower_32_bits(pd_daddr);

	}

	*cs++ = MI_NOOP;

	*cs++ = MI_ARB_ON_OFF | MI_ARB_ENABLE;

	intel_ring_advance(rq, cs);



	intel_ring_advance(rq, cs);