The macro which I incorrectly copied into ah_internal.h assumed
that it'd be called with an AR_SREV_MERLIN_20() check to ensure
it was only enabled for Merlin (AR9280) silicon revision 2.0 or
later.
Trouble is, the 5GHz fast clock EEPROM flag is only valid for
EEPROM revision 16 or greater; it's assumed to be enabled
by default for Merlin rev >= 2.0. This meant it'd be incorrectly
set for AR5416 and AR9160 in 5GHz mode.
This would have affected non-default clock timings such as SIFS,
ACK and slot time. The incorrect slot time was very likely wrong
for 5ghz mode.
a2816e3bed