Re: [Qemu-devel] PPC: Which instruction to fetch at Power-On?

[Fabien Chouteau]

On 03/28/2013 12:46 PM, Alexander Graf wrote:
> 
> On 28.03.2013, at 12:42, Fabien Chouteau wrote:
> 
>>
>> While working on a patch to remove env->hreset_excp_prefix, I'm looking
>> at which instruction should be the fetched first at power-on. I'm lost
>> in all the PPC version and configuration, can anyone (Alex :) can help
>> me with this mess?
> 
> Phew - I'd say just keep the targets you don't know exactly as they are :). 
> That way you at least don't break anything that wasn't broken before.
> 
> For the targets where you do know better (like 7x0), change its behavior to 
> be correct according to the respective spec.
> 

Here's what I found in the UM of almost all the cores supported by QEMU:

Every CPU should start at the hreset address (i.e. excp_prefix + 0x100).

However, some cores don't have a hreset exception (4xx and Book E (e200,
e500)), those cores start at 0xFFFF_FFFC.

-- 
Fabien Chouteau