Index: usr.sbin/bhyve/pci_nvme.c
===================================================================
--- usr.sbin/bhyve/pci_nvme.c
+++ usr.sbin/bhyve/pci_nvme.c
@@ -62,6 +62,7 @@
 #include <sys/errno.h>
 #include <sys/types.h>
 #include <net/ieee_oui.h>
+#include <sys/time.h>
 
 #include <assert.h>
 #include <pthread.h>
@@ -129,6 +130,9 @@
 
 #define	NVME_DOORBELL_OFFSET	offsetof(struct nvme_registers, doorbell)
 
+#define TIMEVAL_DIFF_MILISECONDS(now, from) \
+	((now.tv_sec - from.tv_sec) * 1000 + (now.tv_usec - from.tv_usec) / 1000)
+
 enum nvme_controller_register_offsets {
 	NVME_CR_CAP_LOW = 0x00,
 	NVME_CR_CAP_HI  = 0x04,
@@ -159,6 +163,8 @@
 #define	NVME_CQ_INTEN	0x01
 #define	NVME_CQ_INTCOAL	0x02
 
+#define NVME_FEAT_TIMESTAMP_TIMESTAMP_ORIGIN_SHIFT (1)
+
 struct nvme_completion_queue {
 	struct nvme_completion *qbase;
 	pthread_mutex_t	mtx;
@@ -248,6 +254,12 @@
 	bool namespace_specific;
 };
 
+struct nvme_feature_data {
+	/* timestamp */
+	uint8_t		timestamp_origin;
+	struct timeval	timestamp;
+};
+
 #define NVME_FID_MAX		(NVME_FEAT_ENDURANCE_GROUP_EVENT_CONFIGURATION + 1)
 
 struct pci_nvme_aer {
@@ -290,6 +302,7 @@
 	struct nvme_submission_queue *submit_queues;
 
 	struct nvme_feature_obj feat[NVME_FID_MAX];
+	struct nvme_feature_data feat_data;
 
 	enum nvme_dsm_type dataset_management;
 
@@ -303,6 +316,8 @@
 
 	STAILQ_HEAD(, pci_nvme_aer) aer_list;
 	uint32_t	aer_count;
+
+	struct timeval	power_on_time;
 };
 
 
@@ -359,6 +374,14 @@
     struct nvme_feature_obj *,
     struct nvme_command *,
     struct nvme_completion *);
+static void nvme_feature_timestamp_get(struct pci_nvme_softc *,
+    struct nvme_feature_obj *,
+    struct nvme_command *,
+    struct nvme_completion *);
+static void nvme_feature_timestamp_set(struct pci_nvme_softc *,
+    struct nvme_feature_obj *,
+    struct nvme_command *,
+    struct nvme_completion *);
 
 static __inline void
 cpywithpad(char *dst, size_t dst_size, const char *src, char pad)
@@ -487,7 +510,8 @@
 	    (4 << NVME_CTRLR_DATA_CQES_MIN_SHIFT);
 	cd->nn = 1;	/* number of namespaces */
 
-	cd->oncs = 0;
+	cd->oncs = 1 << NVME_CTRLR_DATA_ONCS_TIMESTAMP_SHIFT;
+
 	switch (sc->dataset_management) {
 	case NVME_DATASET_MANAGEMENT_AUTO:
 		if (sc->nvstore.deallocate)
@@ -503,6 +527,8 @@
 	cd->fna = 0x03;
 
 	cd->power_state[0].mp = 10;
+
+	gettimeofday(&sc->power_on_time, NULL);
 }
 
 /*
@@ -627,6 +653,10 @@
 	    nvme_feature_invalid_cb;
 	sc->feat[NVME_FEAT_PREDICTABLE_LATENCY_MODE_WINDOW].get =
 	    nvme_feature_invalid_cb;
+	sc->feat[NVME_FEAT_TIMESTAMP].set =
+	    nvme_feature_timestamp_set;
+	sc->feat[NVME_FEAT_TIMESTAMP].get =
+	    nvme_feature_timestamp_get;
 }
 
 static void
@@ -1376,6 +1406,55 @@
 	sc->num_q_is_set = true;
 }
 
+static void
+nvme_feature_timestamp_set(struct pci_nvme_softc *sc,
+    struct nvme_feature_obj *feat,
+    struct nvme_command *command,
+    struct nvme_completion *compl)
+{
+	uint64_t miliseconds;
+
+	nvme_prp_memcpy(sc->nsc_pi->pi_vmctx, command->prp1,
+	    command->prp2, (uint8_t*)&miliseconds,
+	    sizeof(miliseconds), NVME_COPY_FROM_PRP);
+
+	DPRINTF("%s: miliseconds: %lu", __func__, miliseconds);
+	miliseconds &= 0xFFFFFFFFFFFF;
+
+	/* Set by Timestamp command */
+	sc->feat_data.timestamp_origin = 1;
+	sc->feat_data.timestamp.tv_sec = miliseconds / 1000;
+	sc->feat_data.timestamp.tv_usec = (miliseconds % 1000) * 1000;
+}
+
+static void
+nvme_feature_timestamp_get(struct pci_nvme_softc *sc,
+    struct nvme_feature_obj *feat,
+    struct nvme_command *command,
+    struct nvme_completion *compl)
+{
+	uint8_t timestamp[8];
+	uint64_t elapsed;
+	struct timeval now;
+
+	gettimeofday(&now, NULL);
+	if (sc->feat_data.timestamp_origin == 0)
+		elapsed = TIMEVAL_DIFF_MILISECONDS(now, sc->power_on_time);
+	else
+		elapsed = TIMEVAL_DIFF_MILISECONDS(now, sc->feat_data.timestamp);
+
+	DPRINTF("%s: elapsed: %lu", __func__, elapsed);
+
+	memcpy(timestamp, (uint8_t*)&elapsed, sizeof(elapsed));
+	timestamp[7] = 0;
+	timestamp[6] = sc->feat_data.timestamp_origin <<
+	    NVME_FEAT_TIMESTAMP_TIMESTAMP_ORIGIN_SHIFT;
+
+	nvme_prp_memcpy(sc->nsc_pi->pi_vmctx, command->prp1,
+	    command->prp2, timestamp,
+	    sizeof(timestamp), NVME_COPY_TO_PRP);
+}
+
 static int
 nvme_opc_set_features(struct pci_nvme_softc *sc, struct nvme_command *command,
 	struct nvme_completion *compl)