[PATCH v6 6/7] cpufreq/cppc: Set the frequency used for computing the capacity

Vincent Guittot vincent.guittot at linaro.org
Thu Nov 9 02:14:37 PST 2023


Save the frequency associated to the performance that has been used when
initializing the capacity of CPUs.
Also, cppc cpufreq driver can register an artificial energy model. In such
case, it needs the frequency for this compute capacity.

Signed-off-by: Vincent Guittot <vincent.guittot at linaro.org>
Acked-by: Sudeep Holla <sudeep.holla at arm.com>
---
 drivers/base/arch_topology.c | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/drivers/base/arch_topology.c b/drivers/base/arch_topology.c
index e8d1cdf1f761..0a2e43728286 100644
--- a/drivers/base/arch_topology.c
+++ b/drivers/base/arch_topology.c
@@ -349,6 +349,7 @@ bool __init topology_parse_cpu_capacity(struct device_node *cpu_node, int cpu)
 
 void topology_init_cpu_capacity_cppc(void)
 {
+	u64 capacity, capacity_scale = 0;
 	struct cppc_perf_caps perf_caps;
 	int cpu;
 
@@ -365,6 +366,10 @@ void topology_init_cpu_capacity_cppc(void)
 		    (perf_caps.highest_perf >= perf_caps.nominal_perf) &&
 		    (perf_caps.highest_perf >= perf_caps.lowest_perf)) {
 			raw_capacity[cpu] = perf_caps.highest_perf;
+			capacity_scale = max_t(u64, capacity_scale, raw_capacity[cpu]);
+
+			per_cpu(capacity_freq_ref, cpu) = cppc_perf_to_khz(&perf_caps, raw_capacity[cpu]);
+
 			pr_debug("cpu_capacity: CPU%d cpu_capacity=%u (raw).\n",
 				 cpu, raw_capacity[cpu]);
 			continue;
@@ -375,7 +380,15 @@ void topology_init_cpu_capacity_cppc(void)
 		goto exit;
 	}
 
-	topology_normalize_cpu_scale();
+	for_each_possible_cpu(cpu) {
+		capacity = raw_capacity[cpu];
+		capacity = div64_u64(capacity << SCHED_CAPACITY_SHIFT,
+				     capacity_scale);
+		topology_set_cpu_scale(cpu, capacity);
+		pr_debug("cpu_capacity: CPU%d cpu_capacity=%lu\n",
+			cpu, topology_get_cpu_scale(cpu));
+	}
+
 	schedule_work(&update_topology_flags_work);
 	pr_debug("cpu_capacity: cpu_capacity initialization done\n");
 
-- 
2.34.1




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