Re: [Qemu-ppc] QEMU PowerPC 464 User Mode Support

[Sanjiv Doshi (sandoshi)]

David
Appreciate your I/p.

I did try to enable 460 as you suggested. However when you look at cpu-models.h 
file you find that it is not complete for 460 core:

========== snippet from cpu-models.h ========

   /* PowerPC 460 family */                                                     
               |                                                                
                                 
#if 0                                                                           
                |                                                               
                                  
    /* Generic PowerPC 464 */                                                   
                |                                                               
                                  
#define CPU_POWERPC_464              CPU_POWERPC_464H90                         
                |                                                               
                                  
#endif                                                                          
                |                                                               
                                  
    /* PowerPC 464 microcontrolers */                                           
                |                                                               
                                  
#if 0                                                                           
                |                                                               
                                  
    CPU_POWERPC_464H90             = xxx,                                       
                |                                                               
                                  
#endif                                                                          
                |                                                               
                                  
#if 0                                                                           
                |                                                               
                                  
    CPU_POWERPC_464H90FP           = xxx,                                       
                |                                                               
                                  
#endif                                                                          
                |                                                               
                                  

===========================

Please pardon my ignorance of powerpc architecture and qemu but from “xxx” seem 
to point that the code is in-complete. Do you have any suggestions?



Thanks - Sanjiv



On 9/28/16, 9:22 PM, "David Gibson" <address@hidden> wrote:

>On Thu, Sep 29, 2016 at 12:10:38AM +0000, Sanjiv Doshi (sandoshi) wrote:
>> Folks
>
>> We are looking for qemu user mode emulation support for PowerPC 464
>> core.
>
>> Has anyone done any work for this core? What is the nearest PowerPC
>> core that is currently supported in user mode that closely resembles
>> 464. We have tried 440GX but does not solve all use cases.
>
>A quick look at the code suggests 460 and 460F CPUs are defined, which
>are probably the closest to what you want.  However, I don't know how
>complete it is.  I don't know that anyone is active working on any
>kind of 44x or 46x emulation, unfortunately.
>
>Since you're only looking at user mode emulation, the number of
>changes should be relatively small (the big differences between
>powerpc cores are at the supervisor / mmu level).
>
>If you're willing, I think the way forward would be to try using the
>460 CPU, see what instructions aren't working and fix or add them as
>you find them.  Unfortunately, I can't really estimate of how big a
>job that will be.
>
>Also be aware that if you did that, you'd probably end up as ppc 46x
>maintainer by default..
>
>-- 
>David Gibson                   | I'll have my music baroque, and my code
>david AT gibson.dropbear.id.au | minimalist, thank you.  NOT _the_ _other_
>                               | _way_ _around_!
>http://www.ozlabs.org/~dgibson