bnxt_en: Improve the delay logic for firmware response.
The current code has 2 problems:
1. The maximum wait time is not long enough. It is about 60% of the
duration specified by the firmware. It is calling usleep_range(600, 800)
for every 1 msec we are supposed to wait.
2. The granularity of the delay is too coarse. Many simple firmware
commands finish in 25 usec or less.
We fix these 2 issues by multiplying the original 1 msec loop counter by
40 and calling usleep_range(25, 40) for each iteration.
There is also a second delay loop to wait for the last DMA word to
complete. This delay loop should be a very short 5 usec wait.
This change results in much faster bring-up/down time:
Before the patch:
time ip link set p4p1 up
real 0m0.120s
user 0m0.001s
sys 0m0.009s
After the patch:
time ip link set p4p1 up
real 0m0.030s
user 0m0.000s
sys 0m0.010s
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
1 file changed