Do a functional access to levels above on a read as a temporary solution for L2's...

Do a functional access to levels above on a read as a temporary solution for L2's in FS

Fix a small writeback bug when missing in the L2 in atomic mode

src/mem/bus.cc:
    Fix a comment to make sense
src/mem/cache/cache_impl.hh:
    Do a functional access to levels above on a read as a temporary solution for L2's in FS
    Also fix a small writeback miss in L2 issue
src/mem/cache/coherence/simple_coherence.hh:
src/mem/cache/coherence/uni_coherence.cc:
src/mem/cache/coherence/uni_coherence.hh:
    Do a functional access to levels above on a read as a temporary solution for L2's in FS
tests/quick/00.hello/ref/alpha/linux/o3-timing/m5stats.txt:
tests/quick/00.hello/ref/alpha/linux/simple-timing/m5stats.txt:
tests/quick/01.hello-2T-smt/ref/alpha/linux/o3-timing/m5stats.txt:
    Update ref's for writeback changes

--HG--
extra : convert_revision : 937febd577b16b7fd97a5a68acaf53541828a251