[PATCH] perf/x86/intel/uncore: Add Granite Rapids CMS PMU support

[PATCH] perf/x86/intel/uncore: Add Granite Rapids CMS PMU support

[Zide Chen]

Add support for the CMS (Common Mesh Stop) uncore PMON unit, shared by
GNR, SRF, GRR, and CWF. One CMS box exists per CHA box, at a fixed MSR
address: 0x3400 + 0x10 * unit_no + <reg offset>.

CMS is not enumerated in the discovery table, so it is added as an
extra MSR uncore type instead of going through the normal gnr_uncores[]
array. Since the CMS unit numbering matches the CHA unit numbering,
build the CMS box rb-tree by mirroring the discovered CHA (die, id)
pairs, ensuring CMS boxes only appear where a corresponding CHA exists.

Make generic_uncore_msr_ops global so the CMS type can reuse it.
Opportunistically add the intel_ prefix to match the naming convention.

Cc: stable@vger.kernel.org
Signed-off-by: Zide Chen <zide.chen@intel.com>
---
 arch/x86/events/intel/uncore_discovery.c |  4 +-
 arch/x86/events/intel/uncore_discovery.h |  1 +
 arch/x86/events/intel/uncore_snbep.c     | 81 +++++++++++++++++++++++-
 3 files changed, 82 insertions(+), 4 deletions(-)

diff --git a/arch/x86/events/intel/uncore_discovery.c b/arch/x86/events/intel/uncore_discovery.c
index 0a22edf4d509..170f299385a0 100644
--- a/arch/x86/events/intel/uncore_discovery.c
+++ b/arch/x86/events/intel/uncore_discovery.c
@@ -532,7 +532,7 @@ static void intel_generic_uncore_msr_disable_event(struct intel_uncore_box *box,
 	wrmsrq(hwc->config_base, 0);
 }
 
-static struct intel_uncore_ops generic_uncore_msr_ops = {
+struct intel_uncore_ops intel_generic_uncore_msr_ops = {
 	.init_box		= intel_generic_uncore_msr_init_box,
 	.disable_box		= intel_generic_uncore_msr_disable_box,
 	.enable_box		= intel_generic_uncore_msr_enable_box,
@@ -743,7 +743,7 @@ static bool uncore_update_uncore_type(enum uncore_access_type type_id,
 
 	switch (type_id) {
 	case UNCORE_ACCESS_MSR:
-		uncore->ops = &generic_uncore_msr_ops;
+		uncore->ops = &intel_generic_uncore_msr_ops;
 		break;
 	case UNCORE_ACCESS_PCI:
 		uncore->ops = &generic_uncore_pci_ops;
diff --git a/arch/x86/events/intel/uncore_discovery.h b/arch/x86/events/intel/uncore_discovery.h
index 142e1b56cfc2..cececf6ecdc5 100644
--- a/arch/x86/events/intel/uncore_discovery.h
+++ b/arch/x86/events/intel/uncore_discovery.h
@@ -151,6 +151,7 @@ void intel_uncore_generic_uncore_mmio_init(void);
 int intel_generic_uncore_msr_init_box(struct intel_uncore_box *box);
 void intel_generic_uncore_msr_disable_box(struct intel_uncore_box *box);
 void intel_generic_uncore_msr_enable_box(struct intel_uncore_box *box);
+extern struct intel_uncore_ops intel_generic_uncore_msr_ops;
 
 int intel_generic_uncore_mmio_init_box(struct intel_uncore_box *box);
 void intel_generic_uncore_mmio_disable_box(struct intel_uncore_box *box);
diff --git a/arch/x86/events/intel/uncore_snbep.c b/arch/x86/events/intel/uncore_snbep.c
index a97cd029db36..3abbc1bbf577 100644
--- a/arch/x86/events/intel/uncore_snbep.c
+++ b/arch/x86/events/intel/uncore_snbep.c
@@ -6492,6 +6492,32 @@ int gnr_uncore_units_ignore[] = {
 	UNCORE_IGNORE_END
 };
 
+/*
+ * One CMS box exists per CHA box, at a fixed MSR address:
+ * 0x3400 + 0x10 * unit_no + <reg offset>.
+ */
+#define GNR_CMS_MSR_PMON_BOX_CTL	0x3400
+#define GNR_CMS_MSR_PMON_CTL0		0x02
+#define GNR_CMS_MSR_PMON_CTR0		0x08
+#define GNR_CMS_MSR_OFFSET		0x10
+/* Type ID for CMS */
+#define UNCORE_GNR_CMS			50
+
+static struct intel_uncore_type gnr_uncore_cms = {
+	/* Keep the PMU name aligned with the published CHACMS event list. */
+	.name			= "chacms",
+	.type_id		= UNCORE_GNR_CMS,
+	.event_mask		= SNBEP_PMON_RAW_EVENT_MASK,
+	.num_counters		= 4,
+	.perf_ctr_bits		= 48,
+	.event_ctl		= GNR_CMS_MSR_PMON_CTL0,
+	.perf_ctr		= GNR_CMS_MSR_PMON_CTR0,
+	.ops			= &intel_generic_uncore_msr_ops,
+	.format_group		= &snbep_uncore_format_group,
+	.attr_update		= uncore_alias_groups,
+	.cleanup_extra_boxes	= spr_extra_boxes_cleanup,
+};
+
 static struct intel_uncore_type gnr_uncore_ubox = {
 	.name			= "ubox",
 	.attr_update		= uncore_alias_groups,
@@ -6595,15 +6621,66 @@ static struct freerunning_counters gnr_iio_freerunning[] = {
 	[SPR_IIO_MSR_BW_OUT]	= { 0x2e0e, 0x10, 0x80, 8, 48 },
 };
 
+/*
+ * Neither the free-running IIO counters nor CMS are covered by the
+ * discovery table, so both are added as "extra" MSR uncore types, in
+ * addition to the ones enumerated in gnr_uncores[].
+ */
+#define UNCORE_GNR_MSR_EXTRA_UNCORES	2
+
+static struct intel_uncore_type *gnr_msr_uncores[UNCORE_GNR_MSR_EXTRA_UNCORES] = {
+	&spr_uncore_iio_free_running,
+	&gnr_uncore_cms,
+};
+
+/* Build the CMS boxes rb-tree by mirroring CHA's discovered boxes. */
+static void gnr_uncore_cms_init_boxes(struct intel_uncore_type **uncores)
+{
+	struct intel_uncore_discovery_unit *cha_unit, *cms_unit;
+	struct intel_uncore_type *cha;
+	struct rb_root *root;
+	struct rb_node *node;
+	u16 num_units = 0;
+
+	cha = uncore_find_type_by_id(uncores, UNCORE_SPR_CHA);
+	if (!cha || !cha->boxes)
+		return;
+
+	root = kzalloc_obj(*root);
+	if (!root)
+		return;
+	*root = RB_ROOT;
+
+	for (node = rb_first(cha->boxes); node; node = rb_next(node)) {
+		cha_unit = rb_entry(node, struct intel_uncore_discovery_unit, node);
+
+		cms_unit = kzalloc_obj(*cms_unit);
+		if (!cms_unit)
+			break;
+
+		cms_unit->id   = cha_unit->id;
+		cms_unit->die  = cha_unit->die;
+		cms_unit->addr = GNR_CMS_MSR_PMON_BOX_CTL +
+				 cha_unit->id * GNR_CMS_MSR_OFFSET;
+
+		uncore_find_add_unit(cms_unit, root, &num_units);
+	}
+
+	gnr_uncore_cms.boxes = root;
+	gnr_uncore_cms.num_boxes = num_units;
+}
+
 void gnr_uncore_cpu_init(void)
 {
 	uncore_msr_uncores = uncore_get_uncores(UNCORE_ACCESS_MSR,
-						UNCORE_SPR_MSR_EXTRA_UNCORES,
-						spr_msr_uncores,
+						UNCORE_GNR_MSR_EXTRA_UNCORES,
+						gnr_msr_uncores,
 						UNCORE_GNR_NUM_UNCORE_TYPES,
 						gnr_uncores);
 	spr_uncore_iio_free_running.num_boxes = uncore_type_max_boxes(uncore_msr_uncores, UNCORE_SPR_IIO);
 	spr_uncore_iio_free_running.freerunning = gnr_iio_freerunning;
+
+	gnr_uncore_cms_init_boxes(uncore_msr_uncores);
 }
 
 int gnr_uncore_pci_init(void)
-- 
2.55.0

Re: [PATCH] perf/x86/intel/uncore: Add Granite Rapids CMS PMU support

[sashiko-bot]

> Add support for the CMS (Common Mesh Stop) uncore PMON unit, shared by
> GNR, SRF, GRR, and CWF. One CMS box exists per CHA box, at a fixed MSR
> address: 0x3400 + 0x10 * unit_no + <reg offset>.
> 
> CMS is not enumerated in the discovery table, so it is added as an
> extra MSR uncore type instead of going through the normal gnr_uncores[]
> array. Since the CMS unit numbering matches the CHA unit numbering,
> build the CMS box rb-tree by mirroring the discovered CHA (die, id)
> pairs, ensuring CMS boxes only appear where a corresponding CHA exists.
> 
> Make generic_uncore_msr_ops global so the CMS type can reuse it.
> Opportunistically add the intel_ prefix to match the naming convention.
> 
> Cc: stable@vger.kernel.org
> Signed-off-by: Zide Chen <zide.chen@intel.com>

Sashiko has reviewed this patch and found no issues. It looks great!

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20261013194005.96615-1-zide.chen@intel.com?part=1