Re: PPC440

[Radoslaw Kujawa <radoslaw.kujawa%c0ff33.net@localhost>]

On Aug 9, 2012, at 4:19 PM, Matt Thomas <matt%3am-software.com@localhost> wrote:

> On Aug 9, 2012, at 6:53 AM, Radoslaw Kujawa wrote:
> 
>>>> And what about ppc440 support (not existing yet)? I does not fit into any 
>>>> current PPC sub architecture (405, OEA, BOOKE) support… 
>>> 
>>> 440 fits under booke.  Support just hasn't risen to the top of my stack
>>> but I designed the booke support so the 440 can just slide right in.
>> 
>> What needs to be added to support 440 under book? I guess at least TLB is 
>> different than in currently supported booke CPUs?
> 
> basically, interrupt control, tlb management, and peripherals.

Could you point me in the right direction? I have a nice PPC460ex-based board 
here, it's a shame to see it not running NetBSD :-). 460ex has a 440 core 
despite the name. I have obtained the PPC440 User's Manual. Now I have some 
free time, so I could work on it, but my knowledge in these areas is still 
lacking*.  

I've read http://www.netbsd.org/docs/kernel/porting_netbsd_arm_soc.html but it 
seems that situation with PPC440 is a bit more complicated, due to this missing 
low-level stuff.

Do I need a JTAG interface to debug the early boot, before I add serial port 
support? The board has U-Boot firmware, is it possible to call U-Boot to print 
debug messages?

* - lacking as in "I barely know what I am doing"

-- 
Best regards,
Radoslaw Kujawa