[PATCH v6 2/4] lib/power: add get and set API for pause duration

[Kevin Laatz <kevin.laatz@intel.com>]

Add new get/set API for configuring 'pause_duration' which used to adjust
the pause mode callback duration.

Signed-off-by: Kevin Laatz <kevin.laatz@intel.com>
Acked-by: Ray Kinsella <mdr@ashroe.eu>
Acked-by: Anatoly Burakov <anatoly.burakov@intel.com>
Tested-by: David Hunt <david.hunt@intel.com>

---
v6: fix unit of pause duration in doc
v5: add doc entry for new API
v3: changed printf to RTE_LOG
---
 doc/guides/prog_guide/power_man.rst |  6 ++++++
 lib/power/rte_power_pmd_mgmt.c      | 25 +++++++++++++++++++++--
 lib/power/rte_power_pmd_mgmt.h      | 31 +++++++++++++++++++++++++++++
 lib/power/version.map               |  2 ++
 4 files changed, 62 insertions(+), 2 deletions(-)

diff --git a/doc/guides/prog_guide/power_man.rst b/doc/guides/prog_guide/power_man.rst
index 5d345f6eb9..266c7544e5 100644
--- a/doc/guides/prog_guide/power_man.rst
+++ b/doc/guides/prog_guide/power_man.rst
@@ -258,6 +258,12 @@ API Overview for Ethernet PMD Power Management
 * **Set Emptypoll Max**: Set the number of empty polls to wait before entering
   sleep state.
 
+* **Get Pause Duration**: Get the configured duration (microseconds) to be used
+  in the Pause callback.
+
+* **Set Pause Duration**: Set the duration of the pause (microseconds) used in
+  the Pause mode callback.
+
 References
 ----------
 
diff --git a/lib/power/rte_power_pmd_mgmt.c b/lib/power/rte_power_pmd_mgmt.c
index dfb7ca9187..1374cc213d 100644
--- a/lib/power/rte_power_pmd_mgmt.c
+++ b/lib/power/rte_power_pmd_mgmt.c
@@ -12,6 +12,7 @@
 #include "rte_power_pmd_mgmt.h"
 
 unsigned int emptypoll_max;
+unsigned int pause_duration;
 
 /* store some internal state */
 static struct pmd_conf_data {
@@ -315,6 +316,7 @@ clb_pause(uint16_t port_id __rte_unused, uint16_t qidx __rte_unused,
 	struct queue_list_entry *queue_conf = arg;
 	struct pmd_core_cfg *lcore_conf;
 	const bool empty = nb_rx == 0;
+	uint32_t pause_duration = rte_power_pmd_mgmt_get_pause_duration();
 
 	lcore_conf = &lcore_cfgs[lcore];
 
@@ -334,11 +336,11 @@ clb_pause(uint16_t port_id __rte_unused, uint16_t qidx __rte_unused,
 		if (global_data.intrinsics_support.power_pause) {
 			const uint64_t cur = rte_rdtsc();
 			const uint64_t wait_tsc =
-					cur + global_data.tsc_per_us;
+					cur + global_data.tsc_per_us * pause_duration;
 			rte_power_pause(wait_tsc);
 		} else {
 			uint64_t i;
-			for (i = 0; i < global_data.pause_per_us; i++)
+			for (i = 0; i < global_data.pause_per_us * pause_duration; i++)
 				rte_pause();
 		}
 	}
@@ -673,6 +675,24 @@ rte_power_pmd_mgmt_get_emptypoll_max(void)
 	return emptypoll_max;
 }
 
+int
+rte_power_pmd_mgmt_set_pause_duration(unsigned int duration)
+{
+	if (duration == 0) {
+		RTE_LOG(ERR, POWER, "Pause duration must be greater than 0, value unchanged");
+		return -EINVAL;
+	}
+	pause_duration = duration;
+
+	return 0;
+}
+
+unsigned int
+rte_power_pmd_mgmt_get_pause_duration(void)
+{
+	return pause_duration;
+}
+
 RTE_INIT(rte_power_ethdev_pmgmt_init) {
 	size_t i;
 
@@ -684,4 +704,5 @@ RTE_INIT(rte_power_ethdev_pmgmt_init) {
 
 	/* initialize config defaults */
 	emptypoll_max = 512;
+	pause_duration = 1;
 }
diff --git a/lib/power/rte_power_pmd_mgmt.h b/lib/power/rte_power_pmd_mgmt.h
index d5a94f8187..18a9c3abb5 100644
--- a/lib/power/rte_power_pmd_mgmt.h
+++ b/lib/power/rte_power_pmd_mgmt.h
@@ -117,6 +117,37 @@ __rte_experimental
 unsigned int
 rte_power_pmd_mgmt_get_emptypoll_max(void);
 
+/**
+ * @warning
+ * @b EXPERIMENTAL: this API may change, or be removed, without prior notice.
+ *
+ * Set the pause_duration. Used to adjust the pause mode callback duration.
+ *
+ * @note Duration must be greater than zero.
+ *
+ * @param duration
+ *   The value to set pause_duration to.
+ * @return
+ *   0 on success
+ *   <0 on error
+ */
+__rte_experimental
+int
+rte_power_pmd_mgmt_set_pause_duration(unsigned int duration);
+
+/**
+ * @warning
+ * @b EXPERIMENTAL: this API may change, or be removed, without prior notice.
+ *
+ * Get the current value of pause_duration.
+ *
+ * @return
+ *   The current pause_duration value.
+ */
+__rte_experimental
+unsigned int
+rte_power_pmd_mgmt_get_pause_duration(void);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/lib/power/version.map b/lib/power/version.map
index 812843c3f3..4673b719f9 100644
--- a/lib/power/version.map
+++ b/lib/power/version.map
@@ -41,5 +41,7 @@ EXPERIMENTAL {
 
 	# added in 22.07
 	rte_power_pmd_mgmt_get_emptypoll_max;
+	rte_power_pmd_mgmt_get_pause_duration;
 	rte_power_pmd_mgmt_set_emptypoll_max;
+	rte_power_pmd_mgmt_set_pause_duration;
 };
-- 
2.31.1