Re: [Qemu-devel] [Qemu-arm] [PATCH v3 01/22] target/arm: A53: Initialize PMCEID[01]

["Philippe Mathieu-Daudé" <f4bug@amsat.org>]

On 03/19/2018 09:35 PM, Aaron Lindsay wrote:
> On Mar 18 23:35, Philippe Mathieu-Daudé wrote:
>> Hi Aaron,
>>
>> On 03/16/2018 09:30 PM, Aaron Lindsay wrote:
>>> A53 advertises ARM_FEATURE_PMU, but wasn't initializing pmceid[01].
>>> pmceid[01] are already being initialized to zero for both A15 and A57.
>>>
>>> Signed-off-by: Aaron Lindsay <alindsay@codeaurora.org>
>>> ---
>>>  target/arm/cpu64.c | 2 ++
>>>  1 file changed, 2 insertions(+)
>>>
>>> diff --git a/target/arm/cpu64.c b/target/arm/cpu64.c
>>> index 991d764..8c4db31 100644
>>> --- a/target/arm/cpu64.c
>>> +++ b/target/arm/cpu64.c
>>> @@ -201,6 +201,8 @@ static void aarch64_a53_initfn(Object *obj)
>>>      cpu->id_isar5 = 0x00011121;
>>>      cpu->id_aa64pfr0 = 0x00002222;
>>>      cpu->id_aa64dfr0 = 0x10305106;
>>> +    cpu->pmceid0 = 0x00000000;
>>> +    cpu->pmceid1 = 0x00000000;
>>>      cpu->id_aa64isar0 = 0x00011120;
>>>      cpu->id_aa64mmfr0 = 0x00001122; /* 40 bit physical addr */
>>>      cpu->dbgdidr = 0x3516d000;
>>>
>>
>> Maybe we can move this at a single place in arm_cpu_post_init():
>>
>>     if (arm_feature(&cpu->env, ARM_FEATURE_PMU)) {
>>         cpu->pmceid0 = 0x00000000;
>>         cpu->pmceid1 = 0x00000000;
>>     }
> 
> I like consolidating the initialization - though I think it can go in
> arm_cpu_realizefn() with the preexisting PMU-related id_aa64dfr0
> initialization since it is constant once you've chosen a type of
> processor. One of the other patches in this set actually already adds
> some PMCEID initialization there based on PMCR.N.

Indeed, arm_cpu_realizefn() is a good place.