Re: [Qemu-devel] [Qemu-ppc] [PATCH 3/5] target-ppc: Build error log

[Benjamin Herrenschmidt]

On Thu, 2014-08-28 at 20:33 +1000, Benjamin Herrenschmidt wrote:
> On Thu, 2014-08-28 at 12:29 +0200, Alexander Graf wrote:
> > 
> > On 28.08.14 12:21, Benjamin Herrenschmidt wrote:
> > > On Thu, 2014-08-28 at 10:36 +0200, Alexander Graf wrote:
> > > 
> > >> So why not put it at 0x7000 then?
> > > 
> > > Because PAPR says it has to be inside RTAS iirc
> > 
> > Please show me the section of PAPR that does say so.
> 
> Actually, we should probably support both options:
> 
> PAPR V2.7
> 
> 7.3.14 Firmware Assisted Non-Maskable Interrupts Option (FWNMI)
> 
> <<
> The difference between ibm,nmi-register and ibm,nmi-register-2 is that
> ibm,nmi-register allocates the error reporting
> structure in RTAS space while ibm,nmi-register-2 places the error
> reporting structure in real page 7. New OS designs
> should use ibm,nmi-register since support for ibm,nmi-register-2 will be
> terminated at some future date.
> >>

Also of interest:

<<
As with all first level interrupt service routines, the SPRG-2 register
is used to save the state of one general purpose
register while the processor computes the location of its state save
area.
>>

Cheers,
Ben.

> 
> Cheers,
> Ben.
>