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
saves about 2.2MB under /usr/include/dev/. Discussed on tech-kern@
recently.
I HOPE to get the list right. The headers I left in are ones
used for MI tools and those whose usage I discovered by grep over tree sources.
Feel free to put needed includes back in if you encounter anything which
should not be removed from lists.
This now provides slightly more functionality than the FreeBSD layer1-newbus
interface. It was meant to be a simple change to one header and a few
c files, but the change rippled all through various stuff.
To prevent a change to the kernel<->userland interface right now the kernel
is now lying about card types to userland (but who cares). This will be fixed
when the userland interface changes, after layer 3 <-> layer 4 has been
fixed.
Functional changes:
Provide a clean interface for hardware drivers to attach to the upper
layers. This will need another small change in the B-channel handling
when a similar change to the layer 3 <-> layer 4 interface happens.
Avoid passing indices into global arrays of pointers around, instead pass
the pointers itself. Don't code hardware driver types by predefined magic
numbers (think LKM). Prepare for detachable drivers (think pcmcia).
While there remove some sets of function pointers always pointing to the
same function (meant to be the configurable set of D channel protocol
handlers). It is unlikely another supported D-channel protocol will fit into
that (maximal layer interface) abstraction. When we get support for another
protocol, we will need to come up with a workable interface. Besides, the
old implementation was, uhm, strange.
remove all (legacy) "i4b_" prefixes outside of sys/netisdn.
Prefix all card specific driver support files with the basename
of the driver bus attachement file.
Renamed here:
i4b_isic_pcmcia.c -> isic_pcmcia.c
i4b_isic_pcmcia.h -> isic_pcmcia.h
i4b_avm_fritz_pcmcia.c -> isic_pcmcia_avm_fritz.c
i4b_elsa_isdnmc.c -> isic_pcmcia_elsa_isdnmc.c
i4b_elsa_mcall.c -> isic_pcmcia_elsa_mcall.c
i4b_sbspeedstar2.c -> isic_pcmcia_sbspeedstar2.c
Don't allocate one large io range, this fails about every time on real
pcmcia buses (not attached to pci/cardbus bridges) because of other
devices interfering in that range. Use the bogusly small region for
now, which works purely by chance (map granularity) on cardbus bridges
too (more or less).
XXX - make this map three different, small regions after layer1 <-> layer2
XXX interface has been brought in shape.
places into the CIS reading code.
The card in question has IO8 only enabled in its CIS info and is apparently
not able to keep up with quick reads. It words fine in a pcmcia slot but
panics(!) the kernel in a TI 1250 cardbus slot. This may be a failure of
the pci cardbus code when initializing this bridge. When finding (and
fixing) that, we should back this change out.
The card I am testing with is not broken, I have multiple versions of it
(AVM Fritz! pcmcia ISDN card), all work fine on windows and all cause
us to panic because of bogus CIS info read.
XXX - panicing because of bogus CIS data is probably another error.
errno otherwise). Actually use that return value to avoid installing an
interrupt handler (possibly sharing an interrupt with other cards!) and
initialising the softc with bogus/half baked values.
established.
XXX real fix: make enable/disable for real and invoke them when needed.
XXX This has to wait until the layer 1 <-> layer 2 interface is
XXX restructured.
This is not unprecedented, as we do it in >100 places in the tree.
If you disagree with this philosophy, take it to tech-kern for a discussion
FIRST before reverting; TNF, not one particular person, owns this file.
