From: Sean Paul Date: Fri, 16 Mar 2012 16:43:22 +0000 (-0400) Subject: drm/i915: Add wait_for in init_ring_common X-Git-Tag: v3.2.28~7 X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=9e7bbc7d2d8641d1375c29aecd6636f3d670b584;p=karo-tx-linux.git drm/i915: Add wait_for in init_ring_common commit f01db988ef6f6c70a6cc36ee71e4a98a68901229 upstream. I have seen a number of "blt ring initialization failed" messages where the ctl or start registers are not the correct value. Upon further inspection, if the code just waited a little bit, it would read the correct value. Adding the wait_for to these reads should eliminate the issue. Signed-off-by: Sean Paul Reviewed-by: Ben Widawsky Signed-off-by: Daniel Vetter Signed-off-by: Ben Hutchings --- diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c index d2cbe5d6f914..4983e590b46d 100644 --- a/drivers/gpu/drm/i915/intel_ringbuffer.c +++ b/drivers/gpu/drm/i915/intel_ringbuffer.c @@ -295,9 +295,9 @@ static int init_ring_common(struct intel_ring_buffer *ring) | RING_VALID); /* If the head is still not zero, the ring is dead */ - if ((I915_READ_CTL(ring) & RING_VALID) == 0 || - I915_READ_START(ring) != obj->gtt_offset || - (I915_READ_HEAD(ring) & HEAD_ADDR) != 0) { + if (wait_for((I915_READ_CTL(ring) & RING_VALID) != 0 && + I915_READ_START(ring) == obj->gtt_offset && + (I915_READ_HEAD(ring) & HEAD_ADDR) == 0, 50)) { DRM_ERROR("%s initialization failed " "ctl %08x head %08x tail %08x start %08x\n", ring->name,