Re: [PATCH] Incorrect segment 0 initialization for PMAC G5

[Nathan Whitehorn <whitehorn%wisc.edu@localhost>]

On 04/02/13 12:33, Phileas Fogg wrote:
> Hi Michael,
>
> we need to extend/rework the OpenPIC interface because
> currently the implementation assumes the little-endian
> architecture which is not true on PowerMAC G5 11,2.
>
> And if we want to reuse some parts of the current OpenPIC
> implementation then we need to extend it and support
> the big-endian architecture too.
>
> I thought of a global variable "openpic_be" which can be set
> to 0 or 1. And "openpic_read" and "openpic_write" methods
> will check it.
>
> And then rename the 2nd parameter of "setup_openpic" to "flags"
> and define 2 flags:
>
> OPENPIC_FLAG_PASSTHROUGH and OPENPIC_FLAG_BIGENDIAN
>
> What do you think ?
>
> Regards

Global variable is probably not what you want. U3 systems have an I2C 
controller on the northbridge which uses the internal PIC which is 
cascaded on such machines to the OpenPIC in the macio device on the PCI 
bus. The result is that they have a big-endian PIC on the northbridge 
and a little-endian PIC in MacIO on the same machine.
-Nathan