svn commit: r197969 - head/sys/conf

[Marcel Moolenaar]

On Oct 13, 2009, at 5:06 PM, M. Warner Losh wrote:

> In message: <2E290D8D-BAF0-4E4E-A352-B00FAFD9DF83 at mac.com>
>            Marcel Moolenaar <xcllnt at mac.com> writes:
> :
> : On Oct 13, 2009, at 10:32 AM, M. Warner Losh wrote:
> : > : > Why?  They should be scanned for on any system with a real isa
> : > bus...
> : > :
> : > : Other than i386, those are?
> : >
> : > So other than i386 and amd64, what systems use the isa device?
> :
> : I interpret the lack of answer as: none.
> :
> : isa(4) is usable on various architectures where the southbridge
> : contains a LPC or similar. The MPC8555 CDS, for example, has a
> : VIA southbridge that we need to talk to in order to get to the
> : ATPIC for dealing with the nested interrupt. isa(4) is the device
> : for this, but isaorm is causing kernel panics simply because
> : the memory between 0xC0000 and 0x100000 is not reserved for ISA
> : option ROMs. Likewise for Itanium, sparc64, etc...
>
> Does this mean that the memory cycles on the I/O bus isn't supported
> for these architectures?

Correct.

>  Or that it is and we just don't implement it
> in the platform specific interfaces for it?

No.

>  The memory space is
> reserved for any system that has a ISA bus, but it might not be at
> physical address 0xc0000, etc.

It's uncommon to have an actual ISA bus and even more uncommon
that the option ROM is actually being used.

> : In short: scanning for option ROMs is not possible in all cases
> : where ISA compatibility is provided.
>
> Why is that?  The platform specific code needs to implement the
> necessary hooks to support this.

There are no hooks to implement. If there is any FreeBSD supported
board that actually needs to have the option ROMs scanned by orm(4),
then we can always make it conditional upon ``device isa_orm''. Making
it dependent on isa(4) is causing real problems and my change limits
the use of orm(4) to platforms where it can possibly have any chance
of being useful -- provided orm(4) is changed to do something useful.

-- 
Marcel Moolenaar
xcllnt at mac.com