2.9.1 is the last version of the intel DDX that supports UMS (User
modesetting), with 2.10 onwards being purely KMS only. As such, this
driver contains backports of almost every correctness or performance
related fix to the rendering layer in later intel drivers. This driver
*REQUIRES* a GEM enabled kernel. it claims to support non-gem mode but
this is essentially unmaintained and due to the way the abstraciton
works is slow, if it works at all (it often does not). You have been
warned.
tested by many many people on tech over the last few weeks.
software rasterise them THEN put them into buffer objects.
read-modify-write of graphics memory is expensive.
2.5x speed increase under heavy trap rendering measured.
Another upstream backport. ok matthieu@
