[PATCH 2/3] pmdomain: core: Show latency/residency for domain idle states in debugfs

Ulf Hansson ulf.hansson at linaro.org
Mon Jan 19 06:31:14 PST 2026


Similar to how cpuidle provides the values for latency and residency for
CPU's idle states through sysfs, let's make the corresponding data for PM
domain's idle states available for user space, via genpd's debugfs support.

Suggested-by: Dhruva Gole <d-gole at ti.com>
Signed-off-by: Ulf Hansson <ulf.hansson at linaro.org>
---
 drivers/pmdomain/core.c | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/drivers/pmdomain/core.c b/drivers/pmdomain/core.c
index 919dff2081d6..bf512ff0857d 100644
--- a/drivers/pmdomain/core.c
+++ b/drivers/pmdomain/core.c
@@ -3809,15 +3809,24 @@ static int idle_states_desc_show(struct seq_file *s, void *data)
 	if (ret)
 		return -ERESTARTSYS;
 
-	seq_puts(s, "State  Name\n");
+	seq_puts(s, "State  Latency(us)  Residency(us)  Name\n");
 
 	for (i = 0; i < genpd->state_count; i++) {
 		struct genpd_power_state *state = &genpd->states[i];
+		u64 latency, residency;
 		char state_name[7];
 
+		latency = state->power_off_latency_ns +
+			state->power_on_latency_ns;
+		do_div(latency, NSEC_PER_USEC);
+
+		residency = state->residency_ns;
+		do_div(residency, NSEC_PER_USEC);
+
 		snprintf(state_name, ARRAY_SIZE(state_name), "S%-5d", i);
-		seq_printf(s, "%-6s %s\n",
-			   state_name, state->name ?: "N/A");
+		seq_printf(s, "%-6s %-12llu %-14llu %s\n",
+			   state_name, latency, residency,
+			   state->name ?: "N/A");
 	}
 
 	genpd_unlock(genpd);
-- 
2.43.0




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