context. For this introduce 3 new xfer tags:
- C_WAIT, equivalent of AT_WAIT
- C_WAITACT, when there is a thread waiting on this xfer to become the active
one (that is, to be at the head of the queue)
- C_FREE, set by ata_free_xfer() when it can't free the xfer because it's
still in use. The holder should then free the xfer ASAP.
If ata_exec_xfer() is called with (C_POLL | C_WAIT), and there is already
xfers to be processed, assert C_WAITACT and sleep.
atastart() checks for C_WAITACT, and wakeup the thread waiting for this xfer
to become active if set. atastart() won't process this xfer, it's the
responsability of the thread waked up to handle it.
Fix (the right way) kern/27421 by Martin Husemann.
- Add an ata_reset_channel() function that performs the common parts
of resetting an ATA channel, which uses the (*ata_reset_channel)()
callback to do the heavy lifting. Adjust callers to use ata_reset_channel()
instead of wdc_reset_channel().
This removes the last wdc-specific code from ata.c!
wdc_regs structure, and array of which (indexed per channel) is pointed
to by struct wdc_softc.
- Move the resulting wdc_channel structure to atavar.h and rename it to
ata_channel. Rename the corresponding flags.
- Add a "ch_ndrive" member to struct ata_channel, which indicates the
maximum number of drives that can be present on the channel. For now,
this is always 2. Add an ATA_MAXDRIVES constant that places an upper
limit on this value, also currently 2.
and kill only pending requests for this drive.
Implement a DRIVE_WAITDRAIN flag, which will cause the active command to
be killed once complete.
Other minor fixes.
Now it's possible to detach a ATA or ATAPI device from ioctl even when
a dd on the raw char partition is running.
struct ata_xfer *active_xfer
to ata_queue. Now the active xfer isn't the head of the queue any more,
this makes a few things easier (this will also help for tagged queuing
support).
Remove the WDCF_ACTIVE flag, test active_xfer != NULL instead.
clean up wdc_free_xfer() and kill_xfer().
Clean up wdc_reset_channel(), and make it issue a ATAPI_SOFT_RESET if the
active command is ATAPI.
In wdc_atapi_get_params(), use AT_WAIT | AT_POLL for ATAPI_SOFT_RESET,
so that we'll use tsleep() instead of delay().
In wdc_atapi_start(), call wdc_dmawait() at the right place.
in tsleep()/wakeup() to appease gcc. Otherwise, the ch_flags value may
be cached in a register in atabus_thread(), and when it sets the WDCF_TH_RUN
bit after tsleep() it may loose loose the changes made by an interrupt handler
or another thread.
Problem analysed by Jukka Andberg on tech-kern.
- wdc_xfer to ata_xfer
- channel_queue to ata_queue
and move them to <dev/ata/atavar.h> so they can be used by non-wdc ATA
controllers. Clean up the member names of these structures while at it.
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.
1) Don't wait for DRQ on an IDENTIFY command -- if it's not set when we see
BSY clear, abort the command and ignore the drive. (Do this by testing
for DRQ in the read/write cases in __wdccommand_intr().)
2) Don't wait for DRQ to deassert when we finish an IDENTIFY (or any other
non-block command that reads data) -- we don't do this for block I/O, and
empirically it doesn't clear on my CF cards at all, causing a pointless 1s
delay.
3) Add comments to some of the delay()s, and add missing ones in wdcreset()
and the WDCC_RECAL in the so-called "pre-ATA" probe.
4) Slightly simplify the reset sequence -- we were doing an extra I/O.
5) Modify the register writability test to make sure that registers are not
overlapped -- this can happen in some weird cases with a missing device 1.
6) Check the error register value after the reset -- if it's not 01h or 81h,
as appropriate (see ATA spec), punt.
Tested with a number of ATA-only, ATAPI-only, mixed ATA-ATAPI, CF, and IDE
disk configurations.
Also remove the SINGLE_DRIVE nonsense again.
the data transfer. This is mandatory for data out commands (although none are
used for now), and not forbiddend for data in commands. Also record if we
did transfers any data.
May solve kern/16159 by making the probe more robust in face of fake identify.
