of both devices are written, and device 0 will respond for device 1 if
device 1 isn't present. Pointed out by Quentin Garnier.
So the only way to know if device 1 is there or not is to send a command, which
is done later.
Detecting the second device here isn't important and won't speed up the probe.
We just need to know if there is at last one device on the bus.
Fix PR kern/22869 from Julio M. Merino Vidal.
call ata_raid_check_component() immediately, and panics since DMA setup
isn't done yet. So, defer the call until attach stage is almost done.
Tested with Promise TX2000.
most polling.
2) Clean up some goofiness in pciide -- get rid of the whole "candisable" path
(it's gratuitous) and simplify the code by calling pciide_map_compat_intr(),
*_set_modes() and wdc_print_modes() from central locations.
3) Add a register writability and register ghost test to eliminate phantom
drives more quickly.
argument. So check so is non-NULL before doing the pointer-chasing
dance to find the PCB. (Unless and until we rework fast-ipsec and
KAME, to pass a struct in_pcbhdr * instead of the struct socket *).
uvm_swap_free() being called with a zero slot; this might have been
the reason for crashes with sysvshm and heavy swapping.
(PR kern/22752 by Tom Spindler)
Confirmed by Chuck Silvers.
another function, always doing a page 0 MODE SENSE to get the block
descriptor if we use READ CAPACITY, and use SMS_DBD on the page 4/5 MODE
SENSE. This does one extra command in some cases, but it separates and
simplifies the code a little.
Why do we prefer READ CAPACITY over READ FORMAT CAPACITIES? Two reasons:
1) It's much older and is much less likely to have had its command code
abused, and is thus "safer" to try first. 2) ALL of my USB flash readers
and pen drives screw up their capacity descriptors -- mostly off-by-one
errors in the size (they return the maximum LBA number instead, a la READ
CAPACITY, which has *never* been how READ FORMAT CAPACITIES was documented
in the MMC spec), and one returns the "no media" code on slots that have
media inserted (despite returning almost-correct data otherwise)!
F*** me with a chainsaw.
