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

Liang, Kan
2023-05-24T19:10:09Z

Hi Peter,

On 2023-05-08 12:16 p.m., Stephane Eranian wrote:
> On Mon, May 8, 2023 at 7:05 AM <kan.liang@linux.intel.com> wrote:
>>
>> From: Kan Liang <kan.liang@linux.intel.com>
>>
>> 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@google.com>
>> Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
>
> Tested-by: Stephane Eranian <eranian@google.com>
>

Gentle ping.

Do you have any comments for the patch?

Thanks,
Kan

>>
>> Cc: stable@vger.kernel.org
>> ---
>> 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
>>