[v3 07/15] powerpc/perf: Add power10_feat to dt_cpu_ftrs

Athira Rajeev atrajeev at linux.vnet.ibm.com
Wed Jul 22 17:55:06 AEST 2020



> On 22-Jul-2020, at 10:11 AM, Jordan Niethe <jniethe5 at gmail.com> wrote:
> 
> On Sat, Jul 18, 2020 at 1:13 AM Athira Rajeev
> <atrajeev at linux.vnet.ibm.com <mailto:atrajeev at linux.vnet.ibm.com>> wrote:
>> 
>> From: Madhavan Srinivasan <maddy at linux.ibm.com>
>> 
>> Add power10 feature function to dt_cpu_ftrs.c along
>> with a power10 specific init() to initialize pmu sprs,
>> sets the oprofile_cpu_type and cpu_features. This will
>> enable performance monitoring unit(PMU) for Power10
>> in CPU features with "performance-monitor-power10".
>> 
>> For PowerISA v3.1, BHRB disable is controlled via Monitor Mode
>> Control Register A (MMCRA) bit, namely "BHRB Recording Disable
>> (BHRBRD)". This patch initializes MMCRA BHRBRD to disable BHRB
>> feature at boot for power10.
>> 
>> Signed-off-by: Madhavan Srinivasan <maddy at linux.ibm.com>
>> ---
>> arch/powerpc/include/asm/reg.h        |  3 +++
>> arch/powerpc/kernel/cpu_setup_power.S |  8 ++++++++
>> arch/powerpc/kernel/dt_cpu_ftrs.c     | 26 ++++++++++++++++++++++++++
>> 3 files changed, 37 insertions(+)
>> 
>> diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h
>> index 21a1b2d..900ada1 100644
>> --- a/arch/powerpc/include/asm/reg.h
>> +++ b/arch/powerpc/include/asm/reg.h
>> @@ -1068,6 +1068,9 @@
>> #define MMCR0_PMC2_LOADMISSTIME        0x5
>> #endif
>> 
>> +/* BHRB disable bit for PowerISA v3.10 */
>> +#define MMCRA_BHRB_DISABLE     0x0000002000000000
> Shouldn't this go under SPRN_MMCRA with the other MMCRA_*.


Hi Jordan

Ok, the definition of MMCRA is under #ifdef for 64 bit .  if I move definition of MMCRA_BHRB_DISABLE along with other SPR's, I also
need to define this for 32-bit to satisfy core-book3s to compile as below:

diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h
index 900ada10762c..7e271657b412 100644
--- a/arch/powerpc/include/asm/reg.h
+++ b/arch/powerpc/include/asm/reg.h
@@ -888,6 +888,8 @@
 #define   MMCRA_SLOT   0x07000000UL /* SLOT bits (37-39) */
 #define   MMCRA_SLOT_SHIFT     24
 #define   MMCRA_SAMPLE_ENABLE 0x00000001UL /* enable sampling */
+/* BHRB disable bit for PowerISA v3.10 */
+#define   MMCRA_BHRB_DISABLE  0x0000002000000000
 #define   POWER6_MMCRA_SDSYNC 0x0000080000000000ULL    /* SDAR/SIAR synced */
 #define   POWER6_MMCRA_SIHV   0x0000040000000000ULL
 #define   POWER6_MMCRA_SIPR   0x0000020000000000ULL
@@ -1068,9 +1070,6 @@
 #define MMCR0_PMC2_LOADMISSTIME        0x5
 #endif
 
-/* BHRB disable bit for PowerISA v3.10 */
-#define MMCRA_BHRB_DISABLE     0x0000002000000000
-
 /*
  * SPRG usage:
  *
diff --git a/arch/powerpc/perf/core-book3s.c b/arch/powerpc/perf/core-book3s.c
index 36baae666387..88068f20827c 100644
--- a/arch/powerpc/perf/core-book3s.c
+++ b/arch/powerpc/perf/core-book3s.c
@@ -94,6 +94,7 @@ static unsigned int freeze_events_kernel = MMCR0_FCS;
 #define SPRN_SIER2             0
 #define SPRN_SIER3             0
 #define MMCRA_SAMPLE_ENABLE    0
+#define MMCRA_BHRB_DISABLE     0
 
 static inline unsigned long perf_ip_adjust(struct pt_regs *regs)
 {



>> +
>> /*
>>  * SPRG usage:
>>  *
>> diff --git a/arch/powerpc/kernel/cpu_setup_power.S b/arch/powerpc/kernel/cpu_setup_power.S
>> index efdcfa7..b8e0d1e 100644
>> --- a/arch/powerpc/kernel/cpu_setup_power.S
>> +++ b/arch/powerpc/kernel/cpu_setup_power.S
>> @@ -94,6 +94,7 @@ _GLOBAL(__restore_cpu_power8)
>> _GLOBAL(__setup_cpu_power10)
>>        mflr    r11
>>        bl      __init_FSCR_power10
>> +       bl      __init_PMU_ISA31
> So we set MMCRA here but then aren't we still going to call __init_PMU
> which will overwrite that?
> Would this setting MMCRA also need to be handled in __restore_cpu_power10?

Thanks for this nice catch !  When I rebased code initial phase, we didn’t had power10 part filled in.
It was a miss from my side in adding PMu init functions and thanks for pointing this out. 
Below patch will call __init_PMU functions in setup and restore. Please check if this looks good

--
diff --git a/arch/powerpc/kernel/cpu_setup_power.S b/arch/powerpc/kernel/cpu_setup_power.S
index efdcfa714106..e672a6c5fd7c 100644
--- a/arch/powerpc/kernel/cpu_setup_power.S
+++ b/arch/powerpc/kernel/cpu_setup_power.S
@@ -94,6 +94,9 @@ _GLOBAL(__restore_cpu_power8)
 _GLOBAL(__setup_cpu_power10)
 	mflr	r11
 	bl	__init_FSCR_power10
+	bl	__init_PMU
+	bl	__init_PMU_ISA31
+	bl	__init_PMU_HV
 	b	1f
 
 _GLOBAL(__setup_cpu_power9)
@@ -124,6 +127,9 @@ _GLOBAL(__setup_cpu_power9)
 _GLOBAL(__restore_cpu_power10)
 	mflr	r11
 	bl	__init_FSCR_power10
+	bl	__init_PMU
+	bl	__init_PMU_ISA31
+	bl	__init_PMU_HV
 	b	1f
 
 _GLOBAL(__restore_cpu_power9)
@@ -233,3 +239,10 @@ __init_PMU_ISA207:
 	li	r5,0
 	mtspr	SPRN_MMCRS,r5
 	blr
+
+__init_PMU_ISA31:
+	li	r5,0
+	mtspr	SPRN_MMCR3,r5
+	LOAD_REG_IMMEDIATE(r5, MMCRA_BHRB_DISABLE)
+	mtspr	SPRN_MMCRA,r5
+	blr

—

>>        b       1f
>> 
>> _GLOBAL(__setup_cpu_power9)
>> @@ -233,3 +234,10 @@ __init_PMU_ISA207:
>>        li      r5,0
>>        mtspr   SPRN_MMCRS,r5
>>        blr
>> +
>> +__init_PMU_ISA31:
>> +       li      r5,0
>> +       mtspr   SPRN_MMCR3,r5
>> +       LOAD_REG_IMMEDIATE(r5, MMCRA_BHRB_DISABLE)
>> +       mtspr   SPRN_MMCRA,r5
>> +       blr
>> diff --git a/arch/powerpc/kernel/dt_cpu_ftrs.c b/arch/powerpc/kernel/dt_cpu_ftrs.c
>> index 3a40951..f482286 100644
>> --- a/arch/powerpc/kernel/dt_cpu_ftrs.c
>> +++ b/arch/powerpc/kernel/dt_cpu_ftrs.c
>> @@ -450,6 +450,31 @@ static int __init feat_enable_pmu_power9(struct dt_cpu_feature *f)
>>        return 1;
>> }
>> 
>> +static void init_pmu_power10(void)
>> +{
>> +       init_pmu_power9();
>> +
>> +       mtspr(SPRN_MMCR3, 0);
>> +       mtspr(SPRN_MMCRA, MMCRA_BHRB_DISABLE);
>> +}
>> +
>> +static int __init feat_enable_pmu_power10(struct dt_cpu_feature *f)
>> +{
>> +       hfscr_pmu_enable();
>> +
>> +       init_pmu_power10();
>> +       init_pmu_registers = init_pmu_power10;
>> +
>> +       cur_cpu_spec->cpu_features |= CPU_FTR_MMCRA;
>> +       cur_cpu_spec->cpu_user_features |= PPC_FEATURE_PSERIES_PERFMON_COMPAT;
>> +
>> +       cur_cpu_spec->num_pmcs          = 6;
>> +       cur_cpu_spec->pmc_type          = PPC_PMC_IBM;
>> +       cur_cpu_spec->oprofile_cpu_type = "ppc64/power10";
>> +
>> +       return 1;
>> +}
>> +
>> static int __init feat_enable_tm(struct dt_cpu_feature *f)
>> {
>> #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
>> @@ -639,6 +664,7 @@ struct dt_cpu_feature_match {
>>        {"pc-relative-addressing", feat_enable, 0},
>>        {"machine-check-power9", feat_enable_mce_power9, 0},
>>        {"performance-monitor-power9", feat_enable_pmu_power9, 0},
>> +       {"performance-monitor-power10", feat_enable_pmu_power10, 0},
>>        {"event-based-branch-v3", feat_enable, 0},
>>        {"random-number-generator", feat_enable, 0},
>>        {"system-call-vectored", feat_disable, 0},
>> --
>> 1.8.3.1

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.ozlabs.org/pipermail/linuxppc-dev/attachments/20200722/f1462051/attachment-0001.htm>


More information about the Linuxppc-dev mailing list