[openib-general] [PATCH 5 of 5] IB/mthca: give reserved MTTs a separate cache line

[Roland Dreier]

 > Let's focus on this comment first.
 > We have at offset 28 bytes:                     
 > 	Log (base 2) of the number of MTT segments reserved for firmware use
 > 
 > And we have
 >         MTHCA_GET(field, outbox, QUERY_DEV_LIM_RSVD_MTT_OFFSET);
 >         dev_lim->reserved_mtts = 1 << (field >> 4);
 > 
 > So it seems reserved_mtts is the number of reserved MTTs and each
 > MTT is 64 bit. Correct?

Actually it seems we have a problem somewhere.  The usage of the field
in the query_dev_lim response seems different between mem-free and
tavor mode: the tavor PRM says it is the log of # of MTT segments
while the memfree PRM says it is the log of the # of MTT entries.

Anyway I need to trace this through more carefully...

 - R.