Re: IBM405GP/GPr OPB bus_space endian (powerpc/ibm4xx/dev/opb.c)

[Shigeyuki Fukushima <shige%netbsd.org@localhost>]

Hi, all.

I think, I'm going to commit its fix.
I'm sorry to trouble tou, but please confirm again now whether is it ok?

Shigeyuki Fukushima wrote:
> Hello,
> 
> Last week, a GPIO framework was imported from OpenBSD.
> This is conflicted with IBM405GP/GPr OPB GPIO device name, "gpio".
> I have fixed the above breakage.
> I send a patch for this modification (with using GPIO fremework).
> 
> The bellow is the subject.
> In the current source (sys/arch/powerpc/ibm4xx/dev/opb),
> byte-ordering for opb(On-chip Peripheral Bus) bus_space is defined by
> Little-Endian (as the following).
> 
>  static struct powerpc_bus_space opb_tag = {
>       _BUS_SPACE_LITTLE_ENDIAN|_BUS_SPACE_MEM_TYPE,
>       0x0, IBM405GP_UART0_BASE, 0x1000
>  };
> 
> Why it is Little-Endian in spite of CPU byte-order (Big-Endian) ?
> Is there any special reason?
> 
> 
> In the gpio (on opb) driver,
> I want to handle some 32-bit registers easily.
> If there is no reason, I want to change bus_space byte-order
> from Little to Big.
> Is it ok?

-- 
Kind Regards,
--- shige
Shigeyuki Fukushima <shige@{FreeBSD,jp.FreeBSD,NetBSD}.org>