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Miscellaneous notes about Prism2 hardware
=========================================

HFA384x command latency

hfa384x_cmd() waits for command completion, so busy bit should never
be set. Average wait for cmd busy was indeed 0 usec.

(Pentium III 400 MHz laptop with Compaq WL100)

cmdcode		average latency
0x00 (INIT)	93880 usec after COR sreset; 54300 usec without COR sreset
0x01 (ENABLE)	9260 usec
0x02 (DISABLE)	9420 usec
0x0a (ALLOC)	20 usec
0x0b (TRANSMIT)	150 usec
0x21 (ACCESS)	120 usec
0x30 (READMIF)	30 usec

Only per packet command is TRANSMIT command. ACCESS is used only with
configuration and others are used only at initial setup or hw reset.

Busy waits caused _only_ due by TRANSMIT command completion waiting:

5 Mbps with 1500 byte packets: 437 packets/sec: 65ms busy wait (6,5%)
5 Mbps with 100 byte packets: 6553 packets/sec: 982ms busy wait (98,3%)
	==> this would take about all CPU; no matter how fast the host CPU is

==> it might be quite useful to handle transmit command completion using
    command completion event; this would remove busy waits from TX