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Re: no ndis* at cardbus? said:
> Given how closely related CardBus and ExpressCard are to PCI, PCMCIA
> should probably be rolled into PCISIG.

Maybe, but for $2000 or 3000 a year to get access to specs
this is also a business model.

> I hope this CompactPCI
> stuff only adds to the PCI standard and doesn't modify it.

It is completely independent, at least as far as software
is concerned. PCI hotplug (rev. 1.1) doesn't contain any
register level specification - all is up to proprietary
controller chips. CompactPCI hotplug requires that the
peripheral cards comply, there is a "capability" defined
(PCI_CAP_CPCI_HOTSWAP in our pcireg.h) which contains the
bits needed at the card side. The host side is proprietary
too afaict.

> Given how closely related CardBus and ExpressCard are to PCI

Depends on what layer you look at - CardBus doesn't have the
IDSEL line which means that it is more a point-to-point
connection than a bus. Just like PCIexpress...
CompactPCI is closer in this respect because it is a real
shared bus.

> hotswap stuff is going to be quite integral (i.e. have
> to autoconfig a driver on insertion, have to delete the device on
> removal

This is (or should be) provided by the autoconf code anyway,
for loadable drivers.
The real difference is how the insertion/removal events are
detected and how power switching/configuration is done. At
this point, all the proprietary controllers are involved.

> drivers have to deal with the device going away

Afaict only CardBus can deal with this, because it is a point-
to-point link with an own interrupt controller. The others
need notification in advance. With shared interrupts this
would be impractical otherwise.

> BTW, what benefit do you foresee ATCA providing?  Are there any
> NetBSD users that could really use it?

It is still young. It is targeted at telecom applications
with high availability, thus all the hotplug stuff. For us
(doing data acquisition systems for physics experiments) it is
interesting because it provides much more data bandwidths
than VME or CompactPCI, and allows cards to burn 150W or so
It will likely not touch a desktop home NetBSD user, but
in a well-designed PCI framework it should be possible
to support, as a module, without disturbing anything else.

best regards

Forschungszentrum Juelich GmbH
52425 Juelich

Sitz der Gesellschaft: Juelich
Eingetragen im Handelsregister des Amtsgerichts Dueren Nr. HR B 3498
Vorsitzende des Aufsichtsrats: MinDir'in Baerbel Brumme-Bothe
Geschaeftsfuehrung: Prof. Dr. Achim Bachem (Vorsitzender),
Dr. Ulrich Krafft (stellv. Vorsitzender), Prof. Dr. Harald Bolt,
Dr. Sebastian M. Schmidt

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