Re: [Qemu-devel] [PATCH v4 14/29] target-ppc: Move POWER7/8 CFAR/DSCR/CTRL/PPR/PCR SPR registration to helpers

[Alexey Kardashevskiy <aik@ozlabs.ru>]

On 06/04/2014 02:54 AM, Tom Musta wrote:
> On 6/3/2014 4:27 AM, Alexey Kardashevskiy wrote:
>> This moves SCFAR/DSCR/CTRL/PPR/PCR PRs to helpers. Later these helpers
>> will be called from generalized init_proc_book3s_64().
>>
>> Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
>> ---
>>  target-ppc/translate_init.c | 70 ++++++++++++++++++++++++++-------------------
>>  1 file changed, 40 insertions(+), 30 deletions(-)
>>
>> diff --git a/target-ppc/translate_init.c b/target-ppc/translate_init.c
>> index d6557f2..576056c 100644
>> --- a/target-ppc/translate_init.c
>> +++ b/target-ppc/translate_init.c
>> @@ -7523,6 +7523,42 @@ static void gen_spr_book3s_purr(CPUPPCState *env)
>>  #endif
>>  }
>>  
>> +static void gen_spr_power6_dbg(CPUPPCState *env)
>> +{
>> +#if !defined(CONFIG_USER_ONLY)
>> +    spr_register(env, SPR_CFAR, "SPR_CFAR",
>> +                 SPR_NOACCESS, SPR_NOACCESS,
>> +                 &spr_read_cfar, &spr_write_cfar,
>> +                 0x00000000);
>> +#endif
>> +}
>> +
>> +static void gen_spr_power5p_common(CPUPPCState *env)
>> +{
>> +    spr_register(env, SPR_PPR, "PPR",
>> +                 &spr_read_generic, &spr_write_generic,
>> +                 &spr_read_generic, &spr_write_generic,
>> +                 0x00000000);
>> +}
>> +
>> +static void gen_spr_power6_common(CPUPPCState *env)
>> +{
>> +#if !defined(CONFIG_USER_ONLY)
>> +    spr_register_kvm(env, SPR_DSCR, "SPR_DSCR",
>> +                     SPR_NOACCESS, SPR_NOACCESS,
>> +                     &spr_read_generic, &spr_write_generic,
>> +                     KVM_REG_PPC_DSCR, 0x00000000);
>> +#endif
>> +    /*
>> +     * Register PCR to report POWERPC_EXCP_PRIV_REG instead of
>> +     * POWERPC_EXCP_INVAL_SPR.
>> +     */
>> +    spr_register(env, SPR_PCR, "PCR",
>> +                 SPR_NOACCESS, SPR_NOACCESS,
>> +                 SPR_NOACCESS, SPR_NOACCESS,
>> +                 0x00000000);
>> +}
>> +
>>  static void gen_spr_power8_tce_address_control(CPUPPCState *env)
>>  {
>>      spr_register(env, SPR_TAR, "TAR",
>> @@ -7745,14 +7781,6 @@ static void init_proc_POWER7 (CPUPPCState *env)
>>      /* Time base */
>>      gen_tbl(env);
>>  #if !defined(CONFIG_USER_ONLY)
>> -    spr_register(env, SPR_CFAR, "SPR_CFAR",
>> -                 SPR_NOACCESS, SPR_NOACCESS,
>> -                 &spr_read_cfar, &spr_write_cfar,
>> -                 0x00000000);
>> -    spr_register_kvm(env, SPR_DSCR, "SPR_DSCR",
>> -                     SPR_NOACCESS, SPR_NOACCESS,
>> -                     &spr_read_generic, &spr_write_generic,
>> -                     KVM_REG_PPC_DSCR, 0x00000000);
>>      spr_register_kvm(env, SPR_POWER_MMCRA, "SPR_MMCRA",
>>                       SPR_NOACCESS, SPR_NOACCESS,
>>                       &spr_read_generic, &spr_write_generic,
>> @@ -7768,24 +7796,15 @@ static void init_proc_POWER7 (CPUPPCState *env)
>>  #endif /* !CONFIG_USER_ONLY */
>>      gen_spr_book3s_ids(env);
>>      gen_spr_book3s_purr(env);
>> +    gen_spr_book3s_common(env);
>> +    gen_spr_power5p_common(env);
>> +    gen_spr_power6_common(env);
>> +    gen_spr_power6_dbg(env);
>>      gen_spr_amr(env);
>> -    /* XXX : not implemented */
>> -    spr_register(env, SPR_CTRL, "SPR_CTRLT",
>> -                 SPR_NOACCESS, SPR_NOACCESS,
>> -                 SPR_NOACCESS, &spr_write_generic,
>> -                 0x80800000);
>> -    spr_register(env, SPR_UCTRL, "SPR_CTRLF",
>> -                 SPR_NOACCESS, SPR_NOACCESS,
>> -                 &spr_read_generic, SPR_NOACCESS,
>> -                 0x80800000);
> 
> 
> Note that by switching to using gen_spr_book3s_common, there is an implicit change in the register names
> ("SPR_CTRLT" --> "SPR_CTRL" and "SPR_CTLRF -> "SPR_UCTRL").  I am not completely sure of the impact of
> this (change in what is seen in the monitor?) .... 

Well, "info registers"/ppc_cpu_dump_state() does not use these names, so I
am not sure if the change will be visible at all.


> But I like your new names better than the old ones :)


Good :)


> 
> 
> 
>> -    /*
>> -     * Register PCR to report POWERPC_EXCP_PRIV_REG instead of
>> -     * POWERPC_EXCP_INVAL_SPR.
>> -     */
>> -    spr_register(env, SPR_PCR, "PCR",
>> -                 SPR_NOACCESS, SPR_NOACCESS,
>> -                 SPR_NOACCESS, SPR_NOACCESS,
>> -                 0x00000000);
>>  }
>>  
> 
> We probably have quite a few hypervisor SPRs that should also be handled this way ????


This is definitely not today.


> Reviewed-by: Tom Musta <tommusta@gmail.com>

got it, thanks!


-- 
Alexey