perf/arm_cspmu: Add pmpidr support

The PMIIDR value is composed by the values in PMPIDR registers.
We can use PMPIDR registers as alternative for device
identification for systems that do not implement PMIIDR.

Reviewed-by: Ilkka Koskinen <ilkka@os.amperecomputing.com>
Signed-off-by: Besar Wicaksono <bwicaksono@nvidia.com>
Signed-off-by: Will Deacon <will@kernel.org>

Author: bwicaksononv

drivers/perf/arm_cspmu/arm_cspmu.c

@@ -322,14 +322,14 @@ static struct arm_cspmu_impl_match impl_match[] = {
 	{
 		.module_name	= "nvidia_cspmu",
 		.pmiidr_val	= ARM_CSPMU_IMPL_ID_NVIDIA,
-		.pmiidr_mask	= ARM_CSPMU_PMIIDR_IMPLEMENTER,
+		.pmiidr_mask	= PMIIDR_IMPLEMENTER,
 		.module		= NULL,
 		.impl_init_ops	= NULL,
 	},
 	{
 		.module_name	= "ampere_cspmu",
 		.pmiidr_val	= ARM_CSPMU_IMPL_ID_AMPERE,
-		.pmiidr_mask	= ARM_CSPMU_PMIIDR_IMPLEMENTER,
+		.pmiidr_mask	= PMIIDR_IMPLEMENTER,
 		.module		= NULL,
 		.impl_init_ops	= NULL,
 	},
@@ -351,6 +351,44 @@ static struct arm_cspmu_impl_match *arm_cspmu_impl_match_get(u32 pmiidr)
 	return NULL;
 }
 
+static u32 arm_cspmu_get_pmiidr(struct arm_cspmu *cspmu)
+{
+	u32 pmiidr, pmpidr;
+
+	pmiidr = readl(cspmu->base0 + PMIIDR);
+
+	if (pmiidr != 0)
+		return pmiidr;
+
+	/* Construct PMIIDR value from PMPIDRs. */
+
+	pmpidr = readl(cspmu->base0 + PMPIDR0);
+	pmiidr |= FIELD_PREP(PMIIDR_PRODUCTID_PART_0,
+				FIELD_GET(PMPIDR0_PART_0, pmpidr));
+
+	pmpidr = readl(cspmu->base0 + PMPIDR1);
+	pmiidr |= FIELD_PREP(PMIIDR_PRODUCTID_PART_1,
+				FIELD_GET(PMPIDR1_PART_1, pmpidr));
+	pmiidr |= FIELD_PREP(PMIIDR_IMPLEMENTER_DES_0,
+				FIELD_GET(PMPIDR1_DES_0, pmpidr));
+
+	pmpidr = readl(cspmu->base0 + PMPIDR2);
+	pmiidr |= FIELD_PREP(PMIIDR_VARIANT,
+				FIELD_GET(PMPIDR2_REVISION, pmpidr));
+	pmiidr |= FIELD_PREP(PMIIDR_IMPLEMENTER_DES_1,
+				FIELD_GET(PMPIDR2_DES_1, pmpidr));
+
+	pmpidr = readl(cspmu->base0 + PMPIDR3);
+	pmiidr |= FIELD_PREP(PMIIDR_REVISION,
+				FIELD_GET(PMPIDR3_REVAND, pmpidr));
+
+	pmpidr = readl(cspmu->base0 + PMPIDR4);
+	pmiidr |= FIELD_PREP(PMIIDR_IMPLEMENTER_DES_2,
+				FIELD_GET(PMPIDR4_DES_2, pmpidr));
+
+	return pmiidr;
+}
+
 #define DEFAULT_IMPL_OP(name)	.name = arm_cspmu_##name
 
 static int arm_cspmu_init_impl_ops(struct arm_cspmu *cspmu)
@@ -361,7 +399,7 @@ static int arm_cspmu_init_impl_ops(struct arm_cspmu *cspmu)
 
 	/* Start with a default PMU implementation */
 	cspmu->impl.module = THIS_MODULE;
-	cspmu->impl.pmiidr = readl(cspmu->base0 + PMIIDR);
+	cspmu->impl.pmiidr = arm_cspmu_get_pmiidr(cspmu);
 	cspmu->impl.ops = (struct arm_cspmu_impl_ops) {
 		DEFAULT_IMPL_OP(get_event_attrs),
 		DEFAULT_IMPL_OP(get_format_attrs),

drivers/perf/arm_cspmu/arm_cspmu.h

@@ -86,6 +86,11 @@
 #define PMCFGR				0xE00
 #define PMCR				0xE04
 #define PMIIDR				0xE08
+#define PMPIDR0				0xFE0
+#define PMPIDR1				0xFE4
+#define PMPIDR2				0xFE8
+#define PMPIDR3				0xFEC
+#define PMPIDR4				0xFD0
 
 /* PMCFGR register field */
 #define PMCFGR_NCG			GENMASK(31, 28)
@@ -115,8 +120,34 @@
 #define PMCR_E				BIT(0)
 
 /* PMIIDR register field */
-#define ARM_CSPMU_PMIIDR_IMPLEMENTER	GENMASK(11, 0)
-#define ARM_CSPMU_PMIIDR_PRODUCTID	GENMASK(31, 20)
+#define PMIIDR_IMPLEMENTER		GENMASK(11, 0)
+#define PMIIDR_IMPLEMENTER_DES_0	GENMASK(3, 0)
+#define PMIIDR_IMPLEMENTER_DES_1	GENMASK(6, 4)
+#define PMIIDR_IMPLEMENTER_DES_2	GENMASK(11, 8)
+#define PMIIDR_REVISION			GENMASK(15, 12)
+#define PMIIDR_VARIANT			GENMASK(19, 16)
+#define PMIIDR_PRODUCTID		GENMASK(31, 20)
+#define PMIIDR_PRODUCTID_PART_0		GENMASK(27, 20)
+#define PMIIDR_PRODUCTID_PART_1		GENMASK(31, 28)
+
+/* PMPIDR0 register field */
+#define PMPIDR0_PART_0			GENMASK(7, 0)
+
+/* PMPIDR1 register field */
+#define PMPIDR1_DES_0			GENMASK(7, 4)
+#define PMPIDR1_PART_1			GENMASK(3, 0)
+
+/* PMPIDR2 register field */
+#define PMPIDR2_REVISION		GENMASK(7, 4)
+#define PMPIDR2_DES_1			GENMASK(2, 0)
+
+/* PMPIDR3 register field */
+#define PMPIDR3_REVAND			GENMASK(7, 4)
+#define PMPIDR3_CMOD			GENMASK(3, 0)
+
+/* PMPIDR4 register field */
+#define PMPIDR4_SIZE			GENMASK(7, 4)
+#define PMPIDR4_DES_2			GENMASK(3, 0)
 
 /* JEDEC-assigned JEP106 identification code */
 #define ARM_CSPMU_IMPL_ID_NVIDIA	0x36B

drivers/perf/arm_cspmu/nvidia_cspmu.c

@@ -322,7 +322,7 @@ static int nv_cspmu_init_ops(struct arm_cspmu *cspmu)
 	if (!ctx)
 		return -ENOMEM;
 
-	prodid = FIELD_GET(ARM_CSPMU_PMIIDR_PRODUCTID, cspmu->impl.pmiidr);
+	prodid = FIELD_GET(PMIIDR_PRODUCTID, cspmu->impl.pmiidr);
 
 	/* Find matching PMU. */
 	for (; match->prodid; match++) {