Re: [Qemu-devel] [PATCH] (RFC) target-ppc: Remove vestigial PowerPC 620 support

[Andreas Färber]

Am 11.02.2013 05:50, schrieb David Gibson:
> The PowerPC 620 was the very first 64-bit PowerPC implementation, but
> hardly anyone ever actually used the chips.  qemu notionally supports the
> 620, but since we don't actually have code to implement the segment table,
> the support is broken (quite likely in other ways too).
> 
> This partch, therefore, removes all remaining pieces of 620 support, to
> stop it cluttering up the platforms we actually care about.
> 
> Signed-off-by: David Gibson <address@hidden>
> ---
>  monitor.c                   |    4 -
>  target-ppc/cpu.h            |   29 -----
>  target-ppc/helper.h         |    1 -
>  target-ppc/machine.c        |    4 +-
>  target-ppc/misc_helper.c    |    6 --
>  target-ppc/mmu_helper.c     |   44 +-------
>  target-ppc/translate.c      |    1 -
>  target-ppc/translate_init.c |  251 
> -------------------------------------------
>  8 files changed, 7 insertions(+), 333 deletions(-)
> 
> Andreas,
> 
> I know Alex Graf is happy to remove the PPC620 stuff, but he suggested
> I talk to you since prep is the only existing ppc machine which would
> ever have supported a PPC620 CPU.  Any objections?
[...]
> diff --git a/target-ppc/translate_init.c b/target-ppc/translate_init.c
> index f038850..7dc1b9b 100644
> --- a/target-ppc/translate_init.c
> +++ b/target-ppc/translate_init.c
[...]
> @@ -9244,10 +9000,6 @@ static const ppc_def_t ppc_defs[] = {
>      POWERPC_DEF("7457A_v1.2",    CPU_POWERPC_74x7A_v12,              7455),
>      /* 64 bits PowerPC                                                       
> */
>  #if defined (TARGET_PPC64)
> -    /* PowerPC 620                                                           
> */
> -    POWERPC_DEF("620",           CPU_POWERPC_620,                    620),
> -    /* Code name for PowerPC 620                                             
> */
> -    POWERPC_DEF("Trident",       CPU_POWERPC_620,                    620),
>  #if defined (TODO)
>      /* PowerPC 630 (POWER3)                                                  
> */
>      POWERPC_DEF("630",           CPU_POWERPC_630,                    630),
[snip]

Are you sure this is what Alex asked you to do? Because he specifically
instructed me NOT to remove any of these model definitions or their PVR
values, even if guarded by defined(TODO), about a week ago.

I'll polish what I have cooking for the CPU models later today; the MMU
code itself has not been touched by my refactorings so far.
We do have a conflict here in that I have moved all code name aliases
from the above definitions array to another array (here: "Trident").
https://github.com/afaerber/qemu-cpu/commits/qom-cpu-ppc-types (WIP)

We were hoping to refactor the current macro mess into a set of
self-contained abstract parent classes, and I was hoping that we might
be able to move them out of translate_init.c afterwards, to speed up
compilation.
Would isolating 620 code in a, say, cpu-620.c help you or is this about
some ifs in disas or whatever code? Or what exactly is your motivation?

The BeBox had a 604e iirc and so far all my PReP testing has been
32-bit. CC'ing Hervé on whether any of his 40P emulations need the 620.

Regards,
Andreas

P.S. Still waiting on your feedback on sPAPR hypercall testing and CPU
hot-plug btw. :-)

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