diff --git a/nimble/controller/include/controller/ble_ll_rfmgmt.h b/nimble/controller/include/controller/ble_ll_rfmgmt.h
index da584e562..37b81a88b 100644
--- a/nimble/controller/include/controller/ble_ll_rfmgmt.h
+++ b/nimble/controller/include/controller/ble_ll_rfmgmt.h
@@ -26,7 +26,7 @@ extern "C" {
 
 void ble_ll_rfmgmt_init(void);
 
-#if MYNEWT_VAL(BLE_XTAL_SETTLE_TIME) > 0
+#if MYNEWT_VAL(BLE_LL_RFMGMT_ENABLE_TIME) > 0
 
 void ble_ll_rfmgmt_reset(void);
 
diff --git a/nimble/controller/src/ble_ll_rfmgmt.c b/nimble/controller/src/ble_ll_rfmgmt.c
index 58dad7c3f..3bf5d5fae 100644
--- a/nimble/controller/src/ble_ll_rfmgmt.c
+++ b/nimble/controller/src/ble_ll_rfmgmt.c
@@ -28,7 +28,7 @@
 #include "controller/ble_ll_sched.h"
 #include "controller/ble_ll_rfmgmt.h"
 
-#if MYNEWT_VAL(BLE_XTAL_SETTLE_TIME) > 0
+#if MYNEWT_VAL(BLE_LL_RFMGMT_ENABLE_TIME) > 0
 
 enum ble_ll_rfmgmt_state {
     RFMGMT_STATE_OFF = 0,
@@ -215,7 +215,7 @@ ble_ll_rfmgmt_init(void)
     rfmgmt->state = RFMGMT_STATE_OFF;
 
     rfmgmt->ticks_to_enabled =
-            ble_ll_usecs_to_ticks_round_up(MYNEWT_VAL(BLE_XTAL_SETTLE_TIME));
+            ble_ll_usecs_to_ticks_round_up(MYNEWT_VAL(BLE_LL_RFMGMT_ENABLE_TIME));
 
     rfmgmt->timer_scheduled = false;
     os_cputime_timer_init(&rfmgmt->timer, ble_ll_rfmgmt_timer_exp, NULL);
diff --git a/nimble/controller/syscfg.yml b/nimble/controller/syscfg.yml
index 06f08b664..ac87b28f4 100644
--- a/nimble/controller/syscfg.yml
+++ b/nimble/controller/syscfg.yml
@@ -175,13 +175,18 @@ syscfg.defs:
             material often.
         value: '32'
 
-    # Crystal setting time
-    BLE_XTAL_SETTLE_TIME:
+    BLE_LL_RFMGMT_ENABLE_TIME:
         description: >
-            The settling time of the high-frequency oscillator. This is
-            used to turn on/off the clock used for the radio (assuming
-            the HW supports this). This value is in microseconds.
-        value: '0'
+            Time required for radio and/or related components to be fully
+            enabled before any request from LL is sent. This value is used
+            by rfmgmt to enable PHY in advance, before request from LL is
+            made. It depends on radio driver selected and may also depend
+            on hardware used:
+            - nrf51 - time required for XTAL to settle
+            - nrf52 - time required for XTAL to settle
+            Value is specified in microseconds. If set to 0, rfmgmt keeps
+            PHY enabled all the time.
+        value: MYNEWT_VAL(BLE_XTAL_SETTLE_TIME)
 
     # Configuration for LL supported features.
     #
@@ -369,6 +374,10 @@ syscfg.defs:
         description: use BLE_LL_DTM instead
         value: 0
         deprecated: 1
+    BLE_XTAL_SETTLE_TIME:
+        description: use BLE_LL_RFMGMT_ENABLE_TIME instead
+        value: 0
+        deprecated: 1
 
 # defunct settings (to be removed eventually)
     BLE_DEVICE: