Re: [RFC PATCH 00/42] target/mips: Reintroduce the R5900 CPU (with more testing)

[Philippe Mathieu-Daudé]

On 2/14/21 6:58 PM, Philippe Mathieu-Daudé wrote:
> The R5900 CPU was removed some time ago (frankly I don't remember
> why). This series add it back, but to prove it works, we also add
> testing at the end.
> 
> The main motivation is to have MIPS R5900 coverage, but to be able
> to run real world r5900 binaries, I had to implement more opcodes.
> 
> 42 patches are a lot, but 3 are already queued in linux-user-for-6.0,
> and the 11 last ones are pure testing. I suppose in next versions
> I'll split the testing patches, but to show the final objective I
> included them in here.
> 
> I tagged it RFC because some parts because:
> 
> - We'd rather not add yet another target, but we need the
>   ILP32-on-64bit ABI (o32 64-bit)
> 
> - RDHWR glibc kludge for user-mode
> 
> - Avocado patches are only here to show the final test.
>   They are useful for my set of tests, but not meant to
>   be merged in mainstream.
> 
> - gitlab jobs are only here to show the tests work.
>   If the target is ever accepted, it would go in an already
>   existing job.
> 
> I'm OK to maintain 64-bit o32 and the testing out of tree, but the
> TCG opcodes are worthwhile review for mainstream.
> 
> Note: there is a sign-extension bug somewhere but I can't find it:
> 
>  $ qemu-r5900o32el busybox free
>   =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
> =A0total =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0used =C2=A0=C2=A0=C2=
> =A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0free =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0sha=
> red =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0buffers
>   =C2=A0Mem: =C2=A0=C2=A0=C2=A0=C2=A0=C2=A03682012 =C2=A0=C2=A0=C2=A0=C2=A0=
> =C2=A0=C2=A0812620 =C2=A0=C2=A0=C2=A0=C2=A0=C2=A02869392 =C2=A0=C2=A0=C2=A0=
> =C2=A0=C2=A01367556 =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0321136
>   Swap: =C2=A0=C2=A0=C2=A0=C2=A0=C2=A02095100 =C2=A0=C2=A0=C2=A0=C2=A0-149854=
> 4 =C2=A0=C2=A0=C2=A0=C2=A0=C2=A03593644
>  Total: =C2=A0=C2=A0=C2=A0=C2=A0=C2=A05777112 =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0-=
> 685924 =C2=A0=C2=A0=C2=A0=C2=A0=C2=A06463036
> 
>  $ free # host
>   =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
> =A0total =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0used =C2=A0=C2=A0=C2=A0=C2=
> =A0=C2=A0=C2=A0=C2=A0free =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0shared =C2=A0buff/cac=
> he =C2=A0=C2=A0available
>  Mem: =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A016264924 =C2=A0=C2=A0=C2=A0=C2=A093=
> 23500 =C2=A0=C2=A0=C2=A0=C2=A02822500 =C2=A0=C2=A0=C2=A0=C2=A01377288 =C2=A0=
> =C2=A0=C2=A0=C2=A04118924 =C2=A0=C2=A0=C2=A0=C2=A05149548
>  Swap: =C2=A0=C2=A0=C2=A0=C2=A0=C2=A018872316 =C2=A0=C2=A0=C2=A011084368 =C2=
> =A0=C2=A0=C2=A0=C2=A07787948

[Same but unescaped]

Note: there is a sign-extension bug somewhere but I can't find it:

 $ qemu-r5900o32el busybox free
               total         used         free       shared      buffers
   Mem:      3682012       812620      2869392      1367556       321136
  Swap:      2095100     -1498544      3593644
 Total:      5777112      -685924      6463036

 $ free # host
               total        used        free      shared  buff/cache
  available
 Mem:       16264924     9323500     2822500     1377288     4118924
    5149548
 Swap:      18872316    11084368     7787948

See the used swap:

  11084368 = 0x00a92250
  -1498544 = 0xffe92250

Regards,

Phil.