perf/x86/intel: Add PMU support for Clearwater Forest

commit 48d66c89dce1e3687174608a5f5c31d5961a9916 upstream.

From the PMU's perspective, Clearwater Forest is similar to the previous
generation Sierra Forest.

The key differences are the ARCH PEBS feature and the new added 3 fixed
counters for topdown L1 metrics events.

The ARCH PEBS is supported in the following patches. This patch provides
support for basic perfmon features and 3 new added fixed counters.

Intel-SIG: commit 48d66c89dce1 perf/x86/intel: Add PMU support for Clearwater Forest.
CWF PMU core backporting

Signed-off-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20250415114428.341182-3-dapeng1.mi@linux.intel.com
[ Quanxian Wang: amend commit log ]
Signed-off-by: Quanxian Wang <quanxian.wang@intel.com>

Author: Dapeng Mi

arch/x86/events/intel/core.c

@@ -2209,6 +2209,18 @@ static struct extra_reg intel_cmt_extra_regs[] __read_mostly = {
 	EVENT_EXTRA_END
 };
 
+EVENT_ATTR_STR(topdown-fe-bound,       td_fe_bound_skt,        "event=0x9c,umask=0x01");
+EVENT_ATTR_STR(topdown-retiring,       td_retiring_skt,        "event=0xc2,umask=0x02");
+EVENT_ATTR_STR(topdown-be-bound,       td_be_bound_skt,        "event=0xa4,umask=0x02");
+
+static struct attribute *skt_events_attrs[] = {
+	EVENT_PTR(td_fe_bound_skt),
+	EVENT_PTR(td_retiring_skt),
+	EVENT_PTR(td_bad_spec_cmt),
+	EVENT_PTR(td_be_bound_skt),
+	NULL,
+};
+
 #define KNL_OT_L2_HITE		BIT_ULL(19) /* Other Tile L2 Hit */
 #define KNL_OT_L2_HITF		BIT_ULL(20) /* Other Tile L2 Hit */
 #define KNL_MCDRAM_LOCAL	BIT_ULL(21)
@@ -6331,6 +6343,18 @@ __init int intel_pmu_init(void)
 		name = "crestmont";
 		break;
 
+	case INTEL_ATOM_DARKMONT_X:
+		intel_pmu_init_skt(NULL);
+		intel_pmu_pebs_data_source_cmt();
+		x86_pmu.pebs_latency_data = cmt_latency_data;
+		x86_pmu.get_event_constraints = cmt_get_event_constraints;
+		td_attr = skt_events_attrs;
+		mem_attr = grt_mem_attrs;
+		extra_attr = cmt_format_attr;
+		pr_cont("Darkmont events, ");
+		name = "darkmont";
+		break;
+
 	case INTEL_WESTMERE:
 	case INTEL_WESTMERE_EP:
 	case INTEL_WESTMERE_EX: