Only rx_usec and tx_usec options for ethtool -C are settable as those
are the only settings that make sense to HW.  Adds driver reporting of
intr coalescing timer value in usec units rather than HW units.
Signed-off-by: NVasanthy Kolluri <vkolluri@cisco.com>
Signed-off-by: NScott Feldman <scofeldm@cisco.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix dev->stop shutdown bug where driver was stopping xmit queue and then
disabling intrs.  Fix is to disable intrs first and then stop the xmit
queue, otherwise an interrupt could cause the queue to be rewoken.  Also,
no need to explicitly do queue servicing because queues are cleaned and
reset back to initial state at end of dev->stop.  Servicing queues also
had the side-effect of also rewakening the xmit queue, which is not what
we want.
Signed-off-by: NVasanthy Kolluri <vkolluri@cisco.com>
Signed-off-by: NScott Feldman <scofeldm@cisco.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Return notify intr credits after notify intr from firmware.  This is
especially important for legacy PCI intr mode, where not returning
credits would cause PBA to remain asserted which would get us right
back into the ISR.
Signed-off-by: NScott Feldman <scofeldm@cisco.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Clarrify reading PBA has no side-effect (clearing).
Add missing GPL license text.
Signed-off-by: NScott Feldman <scofeldm@cisco.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NScott Feldman <scofeldm@cisco.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>