linux/drivers/infiniband
Arthur Jones 8f140b407f IB/ipath: Shadow the gpio_mask register
Once upon a time, GPIO interrupts were rare.  But then a chip bug in
the waldo series forced the use of a GPIO interrupt to signal packet
reception.  This greatly increased the frequency of GPIO interrupts
which have the gpio_mask bits set on the waldo chips.  Other bits in
the gpio_status register are used for I2C clock and data lines, these
bits are usually on.  An "unlikely" annotation leftover from the old
days was improperly applied to these bits, and an unnecessary chip
mmio read was being accessed in the interrupt fast path on waldo.

Remove the stagnant unlikely annotation in the interrupt handler and
keep a shadow copy of the gpio_mask register to avoid the slow mmio
read when testing for interruptable GPIO bits.

Signed-off-by: Arthur Jones <arthur.jones@qlogic.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-05-14 13:22:42 -07:00
..
core IB: Put rlimit accounting struct in struct ib_umem 2007-05-08 18:00:37 -07:00
hw IB/ipath: Shadow the gpio_mask register 2007-05-14 13:22:42 -07:00
ulp header cleaning: don't include smp_lock.h when not used 2007-05-08 11:15:07 -07:00
Kconfig IB/mlx4: Add a driver Mellanox ConnectX InfiniBand adapters 2007-05-08 18:00:38 -07:00
Makefile IB/mlx4: Add a driver Mellanox ConnectX InfiniBand adapters 2007-05-08 18:00:38 -07:00