Commit f0a9f74c authored Dec 17, 2013 by Ben Widawsky Committed by Daniel Vetter Jan 22, 2014

drm/i915: Fix disabled semaphores



The ring will emit too many if semaphores are disabled since we do not
add the correct number to num_dwords anymore.

This was introduced:
commit 52ed2325
Author: Ben Widawsky <benjamin.widawsky@intel.com>
Date:   Mon Dec 16 20:50:38 2013 -0800

    drm/i915: Don't emit mbox updates without semaphores

FWIW, the bug was fixed later in the series.

/me hangs head in shame.

Daniel: Also note that we should have merged the read-only semaphore
modparam before this patch.

Reported-by: Kenneth Graunke <kenneth@whitecape.org>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

parent 8b78f0e5

drivers/gpu/drm/i915/intel_ringbuffer.c

+6 −4

Original line number	Diff line number	Diff line
		@@ -673,11 +673,13 @@ gen6_add_request(struct intel_ring_buffer *ring)
		if (ret)
		return ret;

		if (i915_semaphore_is_enabled(dev)) {
		for_each_ring(useless, dev_priv, i) {
		u32 mbox_reg = ring->signal_mbox[i];
		if (mbox_reg != GEN6_NOSYNC)
		update_mboxes(ring, mbox_reg);
		}
		}

		intel_ring_emit(ring, MI_STORE_DWORD_INDEX);
		intel_ring_emit(ring, I915_GEM_HWS_INDEX << MI_STORE_DWORD_INDEX_SHIFT);