Commit Graph

6 Commits

Author SHA1 Message Date
Justin T. Gibbs
c562189829 Keep track of negotiated transfer parameters for each initiator<->target
connection.

Clean up support for devices featuring the multiple target SCSI ID feature.
On aic7890/91/96/97 chips, we can now assume the target role on multiple
target ids simultaneously.  Although these chips also have sufficient
instruction space to hold to support the initiator and target role at the
same time, the initiator role is currently disabled as it will conflict
(chip design restriction) with the multi-tid feature.  I'll probably add
a nob to enable the initiator (there-by disabling multi-tid) some time
in the future.

Return queue full or busy, depending on the tagged nature of the incoming
request, if our command input queue fills up in host memeory.

Deal with accept target I/O resource shortages.

If we get an underrun on a transaction that wasn't supposed to transmit
any data, don't attempt to print out the S/G list.  The code would
run until hitting a non-present page. (oops)
1999-03-05 23:35:48 +00:00
Justin T. Gibbs
863c602654 Add support for routing initiator transactions to disabled luns to the
black hole device.  The controller will now only accept selections if
the black hole device is present and some other target/lun is enabled
for target mode.

Handle the IGNORE WIDE RESIDUE message.  This support has not been tested.

Checkpoint work on handling ABORT, BUS DEVICE RESET, TERMINATE I/O PROCESS,
and CLEAR QUEUE messages as a target.

Fix a few problems with tagged command handling in target mode.

Wait until the sync offset counter falls to 0 before changing phase
after a data-in transfer completes as the DMA logic seems to indicate
transfer complete as soon as our last REQ is issued.

Simplify some of the target mode message handling code in the sequencer.
1999-01-14 06:14:15 +00:00
Justin T. Gibbs
0ca48af774 Perform a save data pointers operation if a data transfer was performed
in target mode, but we are not completing the command.

Use a template of allowed bus arbitration phases to selectively and
dynamically enable/disable initiator or target (re)selection.

Properly handle timeouts for target role transactions - just go to the
bus free state and report the error to the peripheral driver.

Checkpoint support for the XPT_ABORT_CCB function code.  This currently
handles the accept tio and immediate notify ccb types, but does not
handle the continue target I/O or SCSI I/O ccb types.  This is enough
to handle dynamic target enable/disable events.

Clean up the SCSI reset code so that we perform at most 1 SCSI bus
reset at initialization, the reset requested by the XPT layer.
1998-12-15 08:22:42 +00:00
Justin T. Gibbs
4dd5dcaecd Revamp the way that exceptional message handling is performed so that it
is more robust and common code can be used for both the target and iniator
roles.  The mechanism for tracking negotiation state has also been simplified.

Add support for sync/wide negotiation in target mode and fix many of
the target mode bugs running at higher speeds uncovered.  Make a first
stab at getting all of the bus skew delays correct.  Sync+Wide dataout
transfers still cause problems, but this may be an initiator problem.

Ensure that we exit BITBUCKET mode if the controller is restarted.

Add support for target mode only firmware downloads.  This has been
tested on the aic7880, but should mean that we can perform target mode
on any aic7xxx controller.  Mixed mode (initiator and target roles in
the same firmware load) is currently only supported on the aic7890, but
with optimization, may fit on chips with less instruction space.
1998-12-10 04:14:50 +00:00
Justin T. Gibbs
08c6fbfa40 Change the delivery mechanism for incoming target commands. We now
use a 256 entry ring buffer of descriptersfor this purpose.  This allows
the use of a simple 8bit counter in the sequencer code for tracking start
location.

Entries in the ring buffer now contain a "cmd_valid" byte at their tail.
As an entry is serviced, this byte is cleared by the kernel and set by
the sequencer during its dma of a new entry.  Since this byte is the last
portion of the command touched during a dma, the kernel can use this
byte to ensure the command it processes is completely valid.

The new command format requires a fixed sized DMA from the controller
to deliver which allowed for additional simplification of the sequencer
code.  The hack that required 1 SCB slot to be stolen for incoming
command delivery notification is also gone.
1998-11-23 01:33:47 +00:00
Justin T. Gibbs
3bafc9d432 Massive overhaul of the aic7xxx driver:
- Convert to CAM
 - Use a new DMA based queuing and paging scheme
 - Add preliminary target mode support
 - Add support for the aic789X chips
 - Take advantage of external SRAM on more controllers.
 - Numerous bug fixes and performance improvements.
1998-09-15 07:24:17 +00:00