Re: [PATCH] perf/x86/uncore: Correct the number of CHAs on SPR

[Liang, Kan]

Hi Peter,

On 2023-05-08 12:16 p.m., Stephane Eranian wrote:
> On Mon, May 8, 2023 at 7:05 AM <kan.liang@xxxxxxxxxxxxxxx> wrote:
>>
>> From: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>
>>
>> The number of CHAs from the discovery table on some SPR variants is
>> incorrect, because of a firmware issue. An accurate number can be read
>> from the MSR UNC_CBO_CONFIG.
>>
>> Fixes: 949b11381f81 ("perf/x86/intel/uncore: Add Sapphire Rapids server CHA support")
>> Reported-by: Stephane Eranian <eranian@xxxxxxxxxx>
>> Signed-off-by: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>
> 
> Tested-by: Stephane Eranian <eranian@xxxxxxxxxx>
>

Gentle ping.

Do you have any comments for the patch?

Thanks,
Kan

>>
>> Cc: stable@xxxxxxxxxxxxxxx
>> ---
>>  arch/x86/events/intel/uncore_snbep.c | 11 +++++++++++
>>  1 file changed, 11 insertions(+)
>>
>> diff --git a/arch/x86/events/intel/uncore_snbep.c b/arch/x86/events/intel/uncore_snbep.c
>> index 7d1199554fe3..54abd93828bf 100644
>> --- a/arch/x86/events/intel/uncore_snbep.c
>> +++ b/arch/x86/events/intel/uncore_snbep.c
>> @@ -6138,6 +6138,7 @@ static struct intel_uncore_type spr_uncore_mdf = {
>>  };
>>
>>  #define UNCORE_SPR_NUM_UNCORE_TYPES            12
>> +#define UNCORE_SPR_CHA                         0
>>  #define UNCORE_SPR_IIO                         1
>>  #define UNCORE_SPR_IMC                         6
>>  #define UNCORE_SPR_UPI                         8
>> @@ -6448,12 +6449,22 @@ static int uncore_type_max_boxes(struct intel_uncore_type **types,
>>         return max + 1;
>>  }
>>
>> +#define SPR_MSR_UNC_CBO_CONFIG         0x2FFE
>> +
>>  void spr_uncore_cpu_init(void)
>>  {
>> +       struct intel_uncore_type *type;
>> +       u64 num_cbo;
>> +
>>         uncore_msr_uncores = uncore_get_uncores(UNCORE_ACCESS_MSR,
>>                                                 UNCORE_SPR_MSR_EXTRA_UNCORES,
>>                                                 spr_msr_uncores);
>>
>> +       type = uncore_find_type_by_id(uncore_msr_uncores, UNCORE_SPR_CHA);
>> +       if (type) {
>> +               rdmsrl(SPR_MSR_UNC_CBO_CONFIG, num_cbo);
>> +               type->num_boxes = num_cbo;
>> +       }
>>         spr_uncore_iio_free_running.num_boxes = uncore_type_max_boxes(uncore_msr_uncores, UNCORE_SPR_IIO);
>>  }
>>
>> --
>> 2.35.1
>>