This is a completely rewritten scsipi_xfer execution engine, and the
associated changes to HBA drivers. Overview of changes & features:
- All xfers are queued in the mid-layer, rather than doing so in an
ad-hoc fashion in individual adapter drivers.
- Adapter/channel resource management in the mid-layer, avoids even trying
to start running an xfer if the adapter/channel doesn't have the resources.
- Better communication between the mid-layer and the adapters.
- Asynchronous event notification mechanism from adapter to mid-layer and
peripherals.
- Better peripheral queue management: freeze/thaw, sorted requeueing during
recovery, etc.
- Clean separation of peripherals, adapters, and adapter channels (no more
scsipi_link).
- Kernel thread for each scsipi_channel makes error recovery much easier
(no more dealing with interrupt context when recovering from an error).
- Mid-layer support for tagged queueing: commands can have the tag type
set explicitly, tag IDs are allocated in the mid-layer (thus eliminating
the need to use buggy tag ID allocation schemes in many adapter drivers).
- support for QUEUE FULL and CHECK CONDITION status in mid-layer; the command
will be requeued, or a REQUEST SENSE will be sent as appropriate.
Just before the merge syssrc has been tagged with thorpej_scsipi_beforemerge
be attached with this flag.
Some CF Card (for ex. IBM MicroDrive and SanDisk) doesn't seem to implement
drive select command. In this case, you can't eliminate ghost drive properly.
So you should use this flag to ignore the ghost by force.
wdc drivers (like macppc's obio IDE interface) can use it. Also add
support to both wd attach line and to wdc_print_modes() to print
Ultra/{33,66,100} for respective UDMA modes (From Manuel Bouyer).
delay(1000000) and retry. The 1s delay is needed for some special case only,
no need to hang the machine for that long everytime (especially for PCMCIA).
if an IRQ was not detected, unless the force flag was given. Use this to
detect if the IRQ was for us (closer to shared IRQ for controllers which
don't have their own IRQ handler in pciide.c) and to poll for DMA xfer.
Also makes the timeout recovery code simpler.
- ATAPI cleanup: don't call controller-specific functions from atapiconf.c
(wdc_*), so that it's possible to attach an atapibus to something else
than a wdc/pciide (Hi Lennart :).
Overload struct scsi_adapter with struct atapi_adapter, defined
as struct scsi_adapter + atapi-specific callbacks. scsipi_link still points
to an scsi_adapter, atapi code casts it to atapi_adapter if needed.
Move atapi_softc to atapiconf.h so that it can be used by the underlying
controller code (e.g. atapi_wdc.c).
Add an atapi-specific callback *atapi_probedev(), which probe a drive
in a controller-specific way, allocate the sc_link and fills in the
ataparams if needed. It then calls atapi_probedev() (from atapiconf.c)
to do the generic initialisations and attach the device.
- While I'm there merge and centralise the state definitions in atavar.h.
It should now be possible to use a common ata/atapi routine to set the
drive's modes (will do later).
timeout()/untimeout() API:
- Clients supply callout handle storage, thus eliminating problems of
resource allocation.
- Insertion and removal of callouts is constant time, important as
this facility is used quite a lot in the kernel.
The old timeout()/untimeout() API has been removed from the kernel.
DRQ is not asserted). Closes kern/9346.
- Change the "fake identify before the real one" by a delay(). The real cause
of the problem is that the drive is unresponsive just after a reset.
The real problem (and the solution) showed up after the first change.
- If UDMA 2 is failing try UDMA 1 first, it helps in some cases
- downgrade if we get an error in the first 4000 xfers, or if we get
4 errors in 4000 xfers if the first 4000 went without troubles.
While I'm there commit a local change I have since some time to get my CD
probed: issue a "blanck" IDENTIFY before the one used to detect slave ghosts,
with my drive the first IDENTIFY following a controller reset fails with an
aborted command ...
- fix printing of Ultra-DMA modes (shows up when the drive supports highther
modes than the controller).
- Don't use C_NEEDDONE anymore. We were setting this flag in a possibly
freed wdc_xfer (this didn't create problems, as it was free'd in the POLL
case only, while IRQs are blocked, but it's not good practice anyway
and pool(9) complains about it ;)
2 times in the past
- Set up timeout per xfer instead of per interrupt. This helps with
PIO transfer (we would call timeout()/untimout() several times for a
transfer).
- If we missed an interrupt for a PIO transfer, reset and restart it
immedialy, don't try to recover and continue. If we missed an interrupt we
may have lost a read/write cycle on the IDE bus. If this happens 1) we
corrupt data and 2) we enter an interrupt loop at the end of the xfer, as
the drive has some more data to read/write, but the host thinks the xfer is
done.
This last change fix the (or at last some of the) 'lookup after lost interrupt'
some peoples have been experiencing.
Constantine Sapuntzakis confirmed by Bill Sommerfeld. Although nothing is
supposed to call wakeup on this without setting AT_DONE, it's good practice to
do it this way (the process may be waken up by a setrunnable() call).
false matches on controllers which properly respond to a WDCC_RECAL command.
Should close PR port-i386/7702 (the author tested this patch, and said it
solves his problem).
- Don't rely on ATA signature: some ide controllers seems to not transmit it
properly (SIMIDE on arm32 machines). Instead, when we guess a drive is here
after reset, just mark it as ATA and OLD is it's not ATAPI.
- at attach time, use IDENTIFY to eliminate ghost from the probe. If the
drive had the old flag and IDENTIFY failed, issue a WDCC_RECAL command
to detect a pre-ATA disk. If IDENTIFY succeded, remove the OLD flag,
it's obviously not a pre-ATA disk.
- add a new controller flag, WDC_CAPABILITY_PREATA, used to shorcut parts
of the probe (not necessary, but makes the probe/attach faster). This is
only set by the ISA front-end, all other controllers supported can't have
pre-ATA drives attached.
The mechanism used are more or less the same as before, they have just been
reordered. Should solve port-arm32/7324 (waiting for feedback).
are called from the interrupt or timeout handler, 0 otherwise.
- use this to know if we can busy-wait for wait_for_unbusy or wait_for_ready
This fixes a bug where CDs withot the DRQ_INTR capability would not busy-wait
for the CMDOUT phase.
While I'm there change 2 delay() to DELAY() for consistency, and
garbage-collect some old code from wdcintr() which has been ifdef'd out
for some time now.
IDENTIFY said so: it doesn't help for the drive this was supposed helping,
and seems to break another device.
In interrupt routine, don't return 0 if we are polling: this should fix the
"panic: wdc_exec_command: polled command not done" some people reported
(kern/7269).
DRIVE_OLD, DRIVE_ATA or DRIVE_ATAPI based on register signatures.
The attach routine will issue a IDENTIFY command for ATA/ATAPI disk,
to detect flase matches by the probe routine.
probe/attach should now be fully compliant with ata-4/ata-5. As a side
effect, ATAPI drives which improperly use ATA register signatures should now
be attached as ATAPI.
need to downgrade, downgrade to PIO, as it has been shown if we got CRC errors
in Ultra-DMA mode, we will have silent data corruption in multiword DMA mode
(isn't IDE wonderfull ? :).
Set timeout to 1s for "normal" ata I/O, to minimise the effects of missed
interrupts.
the disk is ready to transfer data, and in ATA-5 the DSC has been obsoleted.
So only wait for DRQ to transfer data. This can be made conditional on the
ATA version if it's proven to break with some drives (worked with all the
drives I have access to).
While I'm there correct a few typos.
In wdc_probe_caps() add code to guess the ATA revision supported (if
ATA4 if Ultra-DMA, ATA2 if PIO mode > 2). We can't rely on param.atap_ata_major
here, at last one Ultra-DMA drive claims to support only ATA-3.
Use the ATA version in ata_perror(), and to try a flush cache command
in a shutdown hook for IDE drives.
- keep the modes supported by the drive in struct ata_drive_datas (will be
later used for downgrading the DMA/PIO mode on error)
- use config flags to force/disable PIO/DMA/UDMA modes
- For the CMD PCI0643/6 setup DMA mode to DMA Read multiple.
bouyer