Restore ATA DMA mode downgrade support everywhere; it's a necessary part
of any system supporting (parallel) ATA DMA. There is hardware out there,
including cobalt, macppc, and sparc64 where this functionality is
necessary to avoid non-functional disks, either in as-shipped hardware
configurations or with add-in cards, or perhaps just with compromised
IDE/PATA cables.

Should address:
PR 58767
PR 59023
PR 59078

If anyone really insists on not having this support they can now turn it
off themselves with `options ATA_NO_DOWNGRADE_MODE`

files.ata: defparam ATADEBUG_WD_MASK

branches: 1.31.6;
ata(4): Add ATA_DOWNGRADE_MODE to opt_ata.h.

This way adding it to kernel config will trigger recompilation.

only include umass_isdata.c if atabus present, and likewise ata_subr.c

only include ata_recovery.c with atabus (same as ata.c which provides
ata_thread_run() used here)

Merge jdolecek-ncqfixes branch

- ata_xfer's are dynamicall allocated as needed using a pool, no longer
limited to number of possible openings supported by controller; dump
and recovery paths use dedicated pre-allocated storage
- moved callouts and condvars from ata_xfer to queue or channel, so that
ata_xfer does not need special initialization
- slot allocation now done when xfer is being activated, uncoupled
from memory allocation; active slots are no longer tracked by controller
code
- channel and drive reset is done always via the atabus thread, and
now executes with channel locked the whole time
- NCQ recovery moved to shared function, and run via the thread also
- added some workarounds for buggy error recovery AHCI emulation in QEMU
and Parallels

designed to primarily fix kern/52614, but might also help with kern/47041
and kern/53183

branches: 1.27.2; 1.27.4; 1.27.6;
split off functions used by 'wd* at umass?' into separate file, unfortunately
the previous approach with NATABUS doesn't work for kernels which include
MODULAR, but not atabus - such as macppc and evbarm

as a stopgap measure, include necessary parts of dev/ata/ata.c even
if no atabus is configured, so that kernels with just 'wd* at umass?'
and no atabus compile; fixes kernel builds for vax, pmax and evbmips
after NCQ branch merge

XXX wd* at umass? still actually untested after the merge, need to discuss
XXX what to do with it

Merge support for SATA NCQ (Native Command Queueing) from jdolecek-ncq branch

ATA subsystem was changed to support several outstanding commands, and use
NCQ xfers if supported by both the controller and the disk, including NCQ
error recovery. Set NCQ high priority for BPRIO_TIMECRITICAL xfers
if supported. Added FUA support.

Done some work towards MP-safe, all ATA code tsleep()/wakeup() replaced
by condvars, and switched most code from spl* to mutexes (separate
wd(4) and ata channel lock).

Introduced new option WD_CHAOS_MONKEY to facilitate testing of error
handling, fixed several uncovered issues. Also fixed several problems
with kernel dump to wd(4) disk.

Tested with ahcisata(4), mvsata(4), siisata(4), piixide(4) on amd64,
with and without port multiplier, both disk and ATAPI devices; other
drivers and archs mechanically adjusted and compile-tested. NCQ is
supported for ahcisata(4) and siisata(4) for any controller, for
mvsata(4) only Gen IIe ones for now. Also enabled ATAPI support in
mvsata(4).

Thanks to Matt Thomas for initial ATA infrastructure patch, and
Jonathan A.Kollasch for siisata(4) NCQ changes and general testing.

Also fixes PR kern/43169 (wd(4)); and PR kern/11811, PR kern/47041,
PR kern/51979 (kernel dump)

branches: 1.24.2; 1.24.28;
Apply back changes that were reverted on Jul 24 and Jul 26 (general ata/wdc
cleanup and SATA PMP support), now that I'm back to fix the fallouts.

Revert, with intention of restoring in a less invasive way, the SATA Port
Multiplier code.

ok christos@

Add sata Port MultiPlier (PMP) support to the ata bus layer,
as described in
http://mail-index.netbsd.org/tech-kern/2012/06/23/msg013442.html
PMP support in integrated to the atabus layer.
struct ata_channel's ch_drive[] is not dynamically allocated, and ch_ndrive
(renamed to ch_ndrives) closely reflects the size of the ch_drive[] array.
Add helper functions atabus_alloc_drives() and atabus_free_drives()
to manage ch_drive[]/ch_ndrives.
Add wdc_maxdrives to struct wdc_softc so that bus front-end can specify
how much drive they really support (master/slave or single).
ata_reset_drive() callback gains a uint32_t *sigp argument which,
when not NULL, will contain the signature of the device being reset.
While there, some cosmetic changes:
- added a drive_type enum to ata_drive_datas, and stop encoding the
probed drive type in drive_flags (we were out of drive flags anyway).
- rename DRIVE_ATAPIST to DRIVE_ATAPIDSCW to better reflect what this
really is
- remove ata_channel->ata_drives, it's redundant with the pointer in
ata_drive_datas
- factor out the interpretation of SATA signatures in sata_interpet_sig()

propagate these changes to the ATA HBA drivers, and add support for PMP
to ahcisata(4) and siisata(4).

Thanks to:
- Protocase (http://www.protocase.com/) which provided a system
with lots of controllers, SATA PMP and drive slots
- Conservation Genomics Laboratory, Department of Biology, New Mexico State
University for hosting the above system
- Brook Milligan, who set up remote access and has been very responsive
when SATA cable move was needed

branches: 1.21.12;
ahcisata(4) and siisata(4) use similar SATA FIS functions, share them.

branches: 1.20.4; 1.20.8; 1.20.12;
Support multiple volumes connected to Intel MatrixRAID controllers.
Code contributed by Juan RP in PR kern/39552.

Add support for Intel MatrixRAID to ataraid(4). It is currently limited
to one volume.

The driver was provided by Juan RP in PR kern/39511.

Add JMicron RAID support to ataraid(4).
Patch provided by Juan RP in PR kern/39395.

Add support for nVidia MediaShield ata raid found on HP ProLiant ML115.
Tested on HEAD and netbsd-4 branch with RAID0, RAID1, SPAN with MCP55 SATA controller.

branches: 1.16.2;
use new "defpseudodev" where appropriate, and remove dummy interface
attribute definitions which were only to trick config(8)

branches: 1.15.30; 1.15.32; 1.15.34; 1.15.36; 1.15.38;
Add support for VIA V-TECH ata raid. Tested on 4.0 with RAID0, RAID1 and
SPAN over a pair of sata drives on a VT8237A SATA Controller.

branches: 1.14.2; 1.14.4; 1.14.8; 1.14.10; 1.14.12;
Exclude wdc_sataprobe() when no SATA controllers are present. Fix
build of *_TINY kernels.

branches: 1.13.20; 1.13.22;
merge ktrace-lwp.

branches: 1.12.2;
Basic support for RAID0 and RAID1 for the Adaptec HostRAID format as found
on the Intel 6300ESB on-board RAID. Adapted from FreeBSD.

branches: 1.11.10;
make the software managed bad-sector list optional
(kernel option WD_SOFTBADSECT)

Don't assume wdc-specific ATA / ATAPI code should be brought in if atabus
or atapibus are configured; use a separate wdc_common attribute to indicate
that the shared wdc code is also present.

Add common routines for SATA controllers. Right now, we have sata_speed(),
which reports the speed encoded in the SStatus register.

Following Matt Thomas's request, rename ata attribute to ata_hl, and
wdc_base to ata. We can now have
atabus* at ata?
in kernel config files.

Make the ATA mid-layer appears as atabus, as proposed in
http://mail-index.netbsd.org/tech-kern/2003/09/25/0006.html
This adds a device (atabus) between IDE controllers and wd or atapibus, to
have each ATA channel show up in the device tree. Later there will be atabus
devices in /dev, so that we can do IOCTL on them.
Each atabus has its own kernel thread, to handle operations that needs polling,
e.g. reset and others.

Device probing on each bus it defered to the atabus thread creation.
This allows to do the reset and basic device probes in parallel, which reduce
boot time on systems with several pciide controllers.

branches: 1.6.2;
Experimental support for RAID volumes configured by ATA "RAID" controllers.
Such RAID controllers are actually just IDE controllers with a BIOS that
can create RAID volumes and write the configuration info to config blocks
on the disks. The BIOS can do I/O to these volumes, and the OS must
understand the config blocks and implement RAID in software in order to be
able to use these volumes.

Only SPAN (simple concatenation) and RAID0 are supported at this time,
and writing back config blocks is also not supported at this time. Currently,
only the Promise configuration scheme is supported, although supporting
the Highpoint scheme should not be too difficult.

In any case, this is sufficient to use the Promise RAID0 volume (thus
preserving the win2k AS installation) on this new Intel server I have.

Thanks to Soren Schmidt for doing the work in FreeBSD; it made this
task much easier. The config block parsing code is adapted from his
work.

whitespace police

Add dependancy to wdc for ata.c, so that 'atapibus at umass' will compile
without wdc or pciide. Closes kern/9842 from Gary Duzan.

branches: 1.3.12;
Merge bouyer-ide

branches: 1.2.2;
Remove "class" declarations, and add "devclass" declarations where
appropriate. Fix several inconsistencies between device class and
attributes. Mostly from Chris Demetriou.

Shuffle wd/wdc driver files around (via repository copies). wdc
now lives in dev/ic, wd now lives in dev/ata. there's now a 'ata'
interface attribute defined in conf/files, but wdc can't go there
yet because some ports still use private versions based on the old
ISA version.