[PATCH 1/1] build modular usb isd200 with modular ide

Paul Mackerras paulus at samba.org
Tue Oct 26 12:05:29 EST 2004

Doug Maxey writes:

> Oh yes, I am aware.  Just happen to be working on PPC64.  Have been
> writing drivers for this base for several years.  It's the olde LE

For Linux or some other OS?

> device vs BE host.  The transfers are done as a 16 bit quantity, PIO.
> And yes, I understand, "we have always done it this way".  Works well
> when you only have to deal with single arch.

No, we haven't always done it this way on PPC. :)  Various different
ways have been tried over the years and this is the only way that
doesn't suck.

> Possibly I am not making point very well, that one is preserving the
> correct byte order and let the structures reflect to native location.

I can't parse that sentence unambiguously...

> Strings get swapped, 16, 32, and 64 bit fields likewise.  I just missed the 
> LE order that is is being preserved for *some* few fields only.

Strings shouldn't get swapped, or at least, strings should only need
to be swapped on a BE platform if they also need to be swapped on an
LE platform.

> There is not a single reference to byte field in the ATA spec for
> IDENTIFY DEVICE.  It just happens that some of the fields are 8 bits long. Or 
> 32 or 64.

And your point is...  ?


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