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.
may retry it as a memory read multiple command under some circumstances.
This can totally confuse some PCI controllers, so ensure that it
will never do this by making sure that the Read Threshold (FIFO
Read Request Control) field of the FIFO Valid Byte Count and Control
registers for both channels (BA5 offset 0x40 and 0x44) are set to
be at least as large as the cacheline size register (the unit of
measure for these registers is 32 bytes).
registers are registers that overlap with others on many controllers, but
which may actually be distinct on some controllers. Right now, the two
shadows are:
- wd_status (usually overlaps wd_command)
- wd_features (usually overlaps wd_error)
Add a new helper function, wdc_init_shadow_regs(), used to initialize
the shadow register handles on controllers where they do actually overlap.
Partially from Jordan Rhody @ Wasabi Systems, Inc.
- 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.
wdc_drvprobe() function. wdc_drvprobe() is used if the controller
does not specify a custom one prior to calling wdcattach(). The
WDC_CAPABILITY_DRVPROBE bit is gone.
