This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.
Boy, I'm glad we're not using sup anymore. This update would have been
insane otherwise.
This involves expanding the support of the SEEPROM routines to deal with
the larger SEEPROMs on these cards and providing a mechanism to share
SCB arrays between multiple controllers.
Most of the 398X support came from Dan Eischer.
ahc_data -> ahc_softc
Clean up some more type bogons I missed from the last pass.
Be more clear when handing the NO_MATCH condition. NO_MATCH can also
happen when the sequencer encounters an SCB we've asked to be aborted.
- Add support for memory mapped I/O.
- Use DMA to get SCBs down to the adapters.
- Remove old paging code.
- Be much smarter about how we allocate SCB space. The old, simple method
wasted almost half a page per SCB. Ooops.
- Make command complete interrupt processing more efficient.
- Break the monolithic ahc_intr into sub-routines. The sub-routines handle
rare, special case events so the function call is not a penalty and the
removal of the code from the main routine most likely improves performance
instruction prefech will work better and less code is pushed into the cache.
- Never, ever allow tagged queueing if a device has disconnection disabled.
- Clean up and simplify timeout code. Many of the changes are to handle the
new DMA scheme.
Add a panic for attempts to page in a non paged out SCB.
Re-order some of the interrupt routine for better performance.
NetBSD/OpenBSD support Submitted by:Noriyuki Soda <soda@sra.co.jp>,
Pete Bentley <pete@demon.net>,
Charles M. Hannum <mycroft@mit.edu>,
Theo de Raadt <deraadt@theos.com>
1) Make the driver "quiet" by sticking most boot messages behind
bootverbose conditionals. This means that you won't see the
sync and wide negotiation, but you will find out if they fail.
2) Add support to the 93cx6 serial eeprom code to read at an abitrary
offset. This is needed so that we can access the second half
of the eeprom on 3940 cards where the second channel's config
is stored.
3) Add flags argument to ahcprobe(). This is used by the pci probe code
to tell the generic driver that an adapter should be treated
as a channel B device as well as notify it of the presence of
external SCB SRAM. These are needed for some motherboard
implementations of the aic7870 and for the 3940 controllers.
4) Print "Channel A"/"Channel B" instead of "Single Channel" for the
two busses of the 3940. I received many reports of confusion
about how the 3940 was probed since most people belived that
only one ahc entry was needed. This will hopefully make it
clearer.
5) Walk the SCBs to determine just how many their are if external SCB
ram is detected.
6) Hard code that external SCB ram is present for the 3940 since it doesn't
use the documented reporting facility for reporting the SRAM. :(
255 commands per channel are supported on the 3940.
7) Read the seeprom starting at addres 32 for the second channel of the
3940 so we get the right info for that channel.
8) Clean up printing of the "Disabling tagged queuing message".
9) Queue timeouts if they occur while we are handling a timeout. The code
was totally unprotected in this scenario.
Reviewed by: Timeout code reviewed by David Greenman <davidg>