3.4-stable review patch. If anyone has any objections, please let me know.
------------------ From: Sean Paul <[email protected]> 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 <[email protected]> Reviewed-by: Ben Widawsky <[email protected]> Signed-off-by: Daniel Vetter <[email protected]> Signed-off-by: Julien Cristau <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/gpu/drm/i915/intel_ringbuffer.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) --- 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_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, -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
