target/ppc/cpu-models: Remove the "default" CPU alias

[PATCH] target/ppc/cpu-models: Remove the "default" CPU alias

Posted by Thomas Huth 1 year, 10 months ago

QEMU emulates a *lot* of PowerPC-based machines - having a CPU
that is named "default" and cannot be used with most of those
machines sounds just wrong. Thus let's remove this old and confusing
alias now.

Signed-off-by: Thomas Huth <thuth@redhat.com>
---
 target/ppc/cpu-models.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/target/ppc/cpu-models.c b/target/ppc/cpu-models.c
index 976be5e0d1..2667440f73 100644
--- a/target/ppc/cpu-models.c
+++ b/target/ppc/cpu-models.c
@@ -918,6 +918,6 @@ PowerPCCPUAlias ppc_cpu_aliases[] = {
 #endif
     { "ppc32", "604" },
     { "ppc", "604" },
-    { "default", "604" },
+
     { NULL, NULL }
 };
-- 
2.31.1

Re: [PATCH] target/ppc/cpu-models: Remove the "default" CPU alias

Posted by Peter Maydell 1 year, 10 months ago

On Tue, 5 Jul 2022 at 16:13, Thomas Huth <thuth@redhat.com> wrote:
>
> QEMU emulates a *lot* of PowerPC-based machines - having a CPU
> that is named "default" and cannot be used with most of those
> machines sounds just wrong. Thus let's remove this old and confusing
> alias now.
>
> Signed-off-by: Thomas Huth <thuth@redhat.com>
> ---
>  target/ppc/cpu-models.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

Do we need to document this in removed-features.rst ?

-- PMM

Re: [PATCH] target/ppc/cpu-models: Remove the "default" CPU alias

Posted by Thomas Huth 1 year, 10 months ago

On 05/07/2022 17.53, Peter Maydell wrote:
> On Tue, 5 Jul 2022 at 16:13, Thomas Huth <thuth@redhat.com> wrote:
>>
>> QEMU emulates a *lot* of PowerPC-based machines - having a CPU
>> that is named "default" and cannot be used with most of those
>> machines sounds just wrong. Thus let's remove this old and confusing
>> alias now.
>>
>> Signed-off-by: Thomas Huth <thuth@redhat.com>
>> ---
>>   target/ppc/cpu-models.c | 2 +-
>>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> Do we need to document this in removed-features.rst ?

Honestly, I don't think that anybody ever really used this in the past 15 
years. It was likely used with the "prep" machine, but we removed that one a 
couple of years already. The only machine that is still using this class of 
PowerPC CPUs is its successor, the 40p machine, but it has a 604 by default 
anyway, and I've never seen anybody using "-cpu default" with that machine. 
So IMHO it's not necessary to document this - but if people here have a 
different feeling, then I can also respin the patch, just let me know.

  Thomas

Re: [PATCH] target/ppc/cpu-models: Remove the "default" CPU alias

Posted by Daniel Henrique Barboza 1 year, 10 months ago


On 7/6/22 03:31, Thomas Huth wrote:
> On 05/07/2022 17.53, Peter Maydell wrote:
>> On Tue, 5 Jul 2022 at 16:13, Thomas Huth <thuth@redhat.com> wrote:
>>>
>>> QEMU emulates a *lot* of PowerPC-based machines - having a CPU
>>> that is named "default" and cannot be used with most of those
>>> machines sounds just wrong. Thus let's remove this old and confusing
>>> alias now.
>>>
>>> Signed-off-by: Thomas Huth <thuth@redhat.com>
>>> ---
>>>   target/ppc/cpu-models.c | 2 +-
>>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> Do we need to document this in removed-features.rst ?
> 
> Honestly, I don't think that anybody ever really used this in the past 15 years. It was likely used with the "prep" machine, but we removed that one a couple of years already. The only machine that is still using this class of PowerPC CPUs is its successor, the 40p machine, but it has a 604 by default anyway, and I've never seen anybody using "-cpu default" with that machine. So IMHO it's not necessary to document this - but if people here have a different feeling, then I can also respin the patch, just let me know.

I'll queue this up as is, don't worry about it.

You can send an extra patch for removed-features.rst if we really think it's
needed. I don't mind the extra documentation, but NGL this is the first time
I've ever heard of '-cpu default'.


Thanks,


Daniel

> 
>   Thomas
>

Re: [PATCH] target/ppc/cpu-models: Remove the "default" CPU alias

Posted by Cédric Le Goater 1 year, 10 months ago

On 7/5/22 17:10, Thomas Huth wrote:
> QEMU emulates a *lot* of PowerPC-based machines - having a CPU
> that is named "default" and cannot be used with most of those
> machines sounds just wrong. Thus let's remove this old and confusing
> alias now.
> 
> Signed-off-by: Thomas Huth <thuth@redhat.com>
> ---
>   target/ppc/cpu-models.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/target/ppc/cpu-models.c b/target/ppc/cpu-models.c
> index 976be5e0d1..2667440f73 100644
> --- a/target/ppc/cpu-models.c
> +++ b/target/ppc/cpu-models.c
> @@ -918,6 +918,6 @@ PowerPCCPUAlias ppc_cpu_aliases[] = {
>   #endif
>       { "ppc32", "604" },
>       { "ppc", "604" },
> -    { "default", "604" },
> +
>       { NULL, NULL }
>   };

A default CPU introduced in 1994. Time to change !

Reviewed-by: Cédric Le Goater <clg@kaod.org>

Thanks,

C.

Re: [PATCH] target/ppc/cpu-models: Remove the "default" CPU alias

Posted by Greg Kurz 1 year, 10 months ago

On Tue,  5 Jul 2022 17:10:30 +0200
Thomas Huth <thuth@redhat.com> wrote:

> QEMU emulates a *lot* of PowerPC-based machines - having a CPU
> that is named "default" and cannot be used with most of those
> machines sounds just wrong. Thus let's remove this old and confusing
> alias now.
> 
> Signed-off-by: Thomas Huth <thuth@redhat.com>
> ---

Good riddance !

Reviewed-by: Greg Kurz <groug@kaod.org>

>  target/ppc/cpu-models.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/target/ppc/cpu-models.c b/target/ppc/cpu-models.c
> index 976be5e0d1..2667440f73 100644
> --- a/target/ppc/cpu-models.c
> +++ b/target/ppc/cpu-models.c
> @@ -918,6 +918,6 @@ PowerPCCPUAlias ppc_cpu_aliases[] = {
>  #endif
>      { "ppc32", "604" },
>      { "ppc", "604" },
> -    { "default", "604" },
> +
>      { NULL, NULL }
>  };