I915_BO_CACHE_COHERENT_FOR_READ
!(obj->cache_coherent & I915_BO_CACHE_COHERENT_FOR_READ))
if (obj->cache_coherent & I915_BO_CACHE_COHERENT_FOR_READ ||
obj->cache_coherent & I915_BO_CACHE_COHERENT_FOR_READ)
obj->cache_coherent = (I915_BO_CACHE_COHERENT_FOR_READ |
obj->cache_coherent = I915_BO_CACHE_COHERENT_FOR_READ;