HO: add handover algo 2 parameters; skip HO 1 if HO 2 is configured

Change-Id: I8811ee8a75be09048042b511ee4bd9bc1de63976

3 files changed, 336 insertions, 12 deletions

diff --git a/include/osmocom/bsc/handover_cfg.h b/include/osmocom/bsc/handover_cfg.h
index 95c0e50ec..63a393eb1 100644
--- a/include/osmocom/bsc/handover_cfg.h
+++ b/include/osmocom/bsc/handover_cfg.h
@@ -1,6 +1,7 @@
 #pragma once
 
 #include <stdbool.h>
+#include <string.h>
 
 struct vty;
 
@@ -17,6 +18,11 @@ struct handover_cfg *ho_cfg_init(void *ctx, struct handover_cfg *higher_level_cf
 #define HO_CFG_STR_WIN_RXQUAL HO_CFG_STR_WIN "Received-Quality averaging\n"
 #define HO_CFG_STR_POWER_BUDGET HO_CFG_STR_HANDOVER "Neighbor cell power triggering\n" "Neighbor cell power triggering\n"
 #define HO_CFG_STR_AVG_COUNT "Number of values to average over\n"
+#define HO_CFG_STR_2 " (HO algo 2 only)\n"
+#define HO_CFG_STR_MIN "Minimum Level/Quality thresholds before triggering HO" HO_CFG_STR_2
+#define HO_CFG_STR_AFS_BIAS "Configure bias to prefer AFS (AMR on TCH/F) over other codecs" HO_CFG_STR_2
+#define HO_CFG_STR_MIN_TCH "Minimum free TCH timeslots before cell is considered congested" HO_CFG_STR_2
+#define HO_CFG_STR_PENALTY_TIME "Set penalty times to wait between repeated handovers" HO_CFG_STR_2
 
 #define as_is(x) (x)
 
@@ -30,6 +36,17 @@ static inline int bool2i(bool arg)
 	return arg? 1 : 0;
 }
 
+static inline bool a2tdma(const char *arg)
+{
+	if (!strcmp(arg, "full"))
+		return true;
+	return false;
+}
+
+static inline const char *tdma2a(bool val)
+{
+	return val? "full" : "subset";
+}
 
 /* The HO_CFG_ONE_MEMBER macro gets redefined, depending on whether to define struct members,
  * function declarations or definitions... It is of the format
@@ -60,6 +77,15 @@ static inline int bool2i(bool arg)
 		"Enable in-call handover\n" \
 		"Enable/disable handover: ") \
 	\
+	HO_CFG_ONE_MEMBER(int, algorithm, 1, \
+		"handover algorithm", "1|2", atoi, "%d", as_is, \
+		HO_CFG_STR_HANDOVER \
+		"Choose algorithm for handover decision\n" \
+		"Algorithm 1: trigger handover based on comparing current cell and neighbor RxLev and RxQual," \
+		" only.\n" \
+		"Algorithm 2: trigger handover on RxLev/RxQual, and also to balance the load across several" \
+		" cells. Consider available codecs. Prevent repeated handover by penalty timers.\n") \
+	\
 	HO_CFG_ONE_MEMBER(unsigned int, rxlev_avg_win, 10, \
 		"handover window rxlev averaging", "<1-10>", atoi, "%u", as_is, \
 		HO_CFG_STR_WIN_RXLEV \
@@ -97,6 +123,95 @@ static inline int bool2i(bool arg)
 		"Maximum Timing-Advance value (i.e. MS distance) before triggering HO\n" \
 		"Maximum Timing-Advance value (i.e. MS distance) before triggering HO\n" \
 		"Maximum Timing-Advance value (i.e. MS distance) before triggering HO\n") \
+	\
+	HO_CFG_ONE_MEMBER(bool, as_active, 0, \
+		"handover assignment", "0|1", a2bool, "%d", bool2i, \
+		HO_CFG_STR_HANDOVER \
+		"Enable or disable in-call channel re-assignment" HO_CFG_STR_2 \
+		"Disable in-call assignment\n" \
+		"Enable in-call assignment\n") \
+	\
+	HO_CFG_ONE_MEMBER(bool, full_tdma, subset, \
+		"handover tdma-measurement", "full|subset", a2tdma, "%s", tdma2a, \
+		HO_CFG_STR_HANDOVER \
+		"Define measurement set of TDMA frames" HO_CFG_STR_2 \
+		"Full set of 102/104 TDMA frames\n" \
+		"Sub set of 4 TDMA frames (SACCH)\n") \
+	\
+	HO_CFG_ONE_MEMBER(int, min_rxlev, -100, \
+		"handover min rxlev", "<-110--50>", atoi, "%d", as_is, \
+		HO_CFG_STR_HANDOVER \
+		HO_CFG_STR_MIN \
+		"How weak may RxLev of an MS become before triggering HO\n" \
+		"minimum RxLev (dBm)\n") \
+	\
+	HO_CFG_ONE_MEMBER(int, min_rxqual, 5, \
+		"handover min rxqual", "<0-7>", atoi, "%d", as_is, \
+		HO_CFG_STR_HANDOVER \
+		HO_CFG_STR_MIN \
+		"How bad may RxQual of an MS become before triggering HO\n" \
+		"minimum RxQual (dBm)\n") \
+	\
+	HO_CFG_ONE_MEMBER(int, afs_bias_rxlev, 0, \
+		"handover afs-bias rxlev", "<0-20>", atoi, "%d", as_is, \
+		HO_CFG_STR_HANDOVER \
+		HO_CFG_STR_AFS_BIAS \
+		"RxLev improvement bias for AFS over other codecs\n" \
+		"Virtual RxLev improvement (dBm)\n") \
+	\
+	HO_CFG_ONE_MEMBER(int, afs_bias_rxqual, 0, \
+		"handover afs-bias rxqual", "<0-7>", atoi, "%d", as_is, \
+		HO_CFG_STR_HANDOVER \
+		HO_CFG_STR_AFS_BIAS \
+		"RxQual improvement bias for AFS over other codecs\n" \
+		"Virtual RxQual improvement (dBm)\n") \
+	\
+	HO_CFG_ONE_MEMBER(int, tchf_min_slots, 0, \
+		"handover min-free-slots tch/f", "<0-9999>", atoi, "%d", as_is, \
+		HO_CFG_STR_HANDOVER \
+		HO_CFG_STR_MIN_TCH \
+		"Minimum free TCH/F timeslots before cell is considered congested\n" \
+		"Number of TCH/F slots\n") \
+	\
+	HO_CFG_ONE_MEMBER(int, tchh_min_slots, 0, \
+		"handover min-free-slots tch/h", "<0-9999>", atoi, "%d", as_is, \
+		HO_CFG_STR_HANDOVER \
+		HO_CFG_STR_MIN_TCH \
+		"Minimum free TCH/H timeslots before cell is considered congested\n" \
+		"Number of TCH/H slots\n") \
+	\
+	HO_CFG_ONE_MEMBER(int, ho_max, 9999, \
+		"handover max-handovers", "<1-9999>", atoi, "%d", as_is, \
+		HO_CFG_STR_HANDOVER \
+		"Maximum number of concurrent handovers allowed per cell" HO_CFG_STR_2 \
+		"Number\n") \
+	\
+	HO_CFG_ONE_MEMBER(int, penalty_max_dist, 300, \
+		"handover penalty-time max-distance", "<0-99999>", atoi, "%d", as_is, \
+		HO_CFG_STR_HANDOVER \
+		HO_CFG_STR_PENALTY_TIME \
+		"Time to suspend handovers after leaving this cell due to exceeding max distance\n" \
+		"Seconds\n") \
+	\
+	HO_CFG_ONE_MEMBER(int, penalty_failed_ho, 60, \
+		"handover penalty-time failed-ho", "<0-99999>", atoi, "%d", as_is, \
+		HO_CFG_STR_HANDOVER \
+		HO_CFG_STR_PENALTY_TIME \
+		"Time to suspend handovers after handover failure to this cell\n" \
+		"Seconds\n") \
+	\
+	HO_CFG_ONE_MEMBER(int, penalty_failed_as, 60, \
+		"handover penalty-time failed-assignment", "<0-99999>", atoi, "%d", as_is, \
+		HO_CFG_STR_HANDOVER \
+		HO_CFG_STR_PENALTY_TIME \
+		"Time to suspend handovers after assignment failure in this cell\n" \
+		"Seconds\n") \
+	\
+	HO_CFG_ONE_MEMBER(int, retries, 0, \
+		"handover retries", "<0-9>", atoi, "%d", as_is, \
+		HO_CFG_STR_HANDOVER \
+		"Immediately retry on handover/assignment failure" HO_CFG_STR_2 \
+		"Number of retries\n") \
 
 
 /* Declare public API for handover cfg parameters... */
diff --git a/src/libbsc/handover_decision.c b/src/libbsc/handover_decision.c
index 158fc1c7c..1e2e0d944 100644
--- a/src/libbsc/handover_decision.c
+++ b/src/libbsc/handover_decision.c
@@ -265,6 +265,10 @@ static int process_meas_rep(struct gsm_meas_rep *mr)
 	int av_rxlev;
 	unsigned int pwr_interval;
 
+	/* If this cell does not use handover algorithm 1, then we're not responsible. */
+	if (ho_get_algorithm(bts->ho) != 1)
+		return 0;
+
 	/* we currently only do handover for TCH channels */
 	switch (mr->lchan->type) {
 	case GSM_LCHAN_TCH_F:
diff --git a/tests/handover_cfg.vty b/tests/handover_cfg.vty
index e181797f6..ff67c8ff0 100644
--- a/tests/handover_cfg.vty
+++ b/tests/handover_cfg.vty
@@ -143,30 +143,73 @@ network
   handover power budget interval 23
 ... !handover
 
+OsmoBSC(config-net-bts)# ### Verify that 'min rxlev' value range stops at -50
+OsmoBSC(config-net-bts)# handover min rxlev ?
+  <-110--50>  minimum RxLev (dBm)
+  default     Use default (-100), remove explicit setting on this node
+OsmoBSC(config-net-bts)# handover min rxlev -111
+% Unknown command.
+OsmoBSC(config-net-bts)# handover min rxlev -110
+OsmoBSC(config-net-bts)# handover min rxlev -50
+OsmoBSC(config-net-bts)# handover min rxlev -49
+% Unknown command.
+OsmoBSC(config-net-bts)# handover min rxlev 50
+% Unknown command.
+OsmoBSC(config-net-bts)# handover min rxlev default
+% 'handover min rxlev' setting removed, now is -100
+
 
 OsmoBSC(config-net-bts)# ### Checking online help
 OsmoBSC(config-net-bts)# exit
 OsmoBSC(config-net)# list
 ...
   handover (0|1|default)
+  handover algorithm (1|2|default)
   handover window rxlev averaging (<1-10>|default)
   handover window rxqual averaging (<1-10>|default)
   handover window rxlev neighbor averaging (<1-10>|default)
   handover power budget interval (<1-99>|default)
   handover power budget hysteresis (<0-999>|default)
   handover maximum distance (<0-9999>|default)
+  handover assignment (0|1|default)
+  handover tdma-measurement (full|subset|default)
+  handover min rxlev (<-110--50>|default)
+  handover min rxqual (<0-7>|default)
+  handover afs-bias rxlev (<0-20>|default)
+  handover afs-bias rxqual (<0-7>|default)
+  handover min-free-slots tch/f (<0-9999>|default)
+  handover min-free-slots tch/h (<0-9999>|default)
+  handover max-handovers (<1-9999>|default)
+  handover penalty-time max-distance (<0-99999>|default)
+  handover penalty-time failed-ho (<0-99999>|default)
+  handover penalty-time failed-assignment (<0-99999>|default)
+  handover retries (<0-9>|default)
 ...
 
 OsmoBSC(config-net)# handover?
   handover  Handover options
 
 OsmoBSC(config-net)# handover ?
-  0        Disable in-call handover
-  1        Enable in-call handover
-  default  Enable/disable handover: Use default (0), remove explicit setting on this node
-  window   Measurement averaging settings
-  power    Neighbor cell power triggering
-  maximum  Maximum Timing-Advance value (i.e. MS distance) before triggering HO
+  0                 Disable in-call handover
+  1                 Enable in-call handover
+  default           Enable/disable handover: Use default (0), remove explicit setting on this node
+  algorithm         Choose algorithm for handover decision
+  window            Measurement averaging settings
+  power             Neighbor cell power triggering
+  maximum           Maximum Timing-Advance value (i.e. MS distance) before triggering HO
+  assignment        Enable or disable in-call channel re-assignment (HO algo 2 only)
+  tdma-measurement  Define measurement set of TDMA frames (HO algo 2 only)
+  min               Minimum Level/Quality thresholds before triggering HO (HO algo 2 only)
+  afs-bias          Configure bias to prefer AFS (AMR on TCH/F) over other codecs (HO algo 2 only)
+  min-free-slots    Minimum free TCH timeslots before cell is considered congested (HO algo 2 only)
+  max-handovers     Maximum number of concurrent handovers allowed per cell (HO algo 2 only)
+  penalty-time      Set penalty times to wait between repeated handovers (HO algo 2 only)
+  retries           Immediately retry on handover/assignment failure (HO algo 2 only)
+
+OsmoBSC(config-net)# handover algorithm ?
+  1        Algorithm 1: trigger handover based on comparing current cell and neighbor RxLev and RxQual, only.
+  2        Algorithm 2: trigger handover on RxLev/RxQual, and also to balance the load across several cells. Consider available codecs. Prevent repeated handover by penalty timers.
+  default  Use default (1), remove explicit setting on this node
 
 OsmoBSC(config-net)# handover window ?
   rxlev   Received-Level averaging
@@ -216,6 +259,80 @@ OsmoBSC(config-net)# handover maximum distance ?
   <0-9999>  Maximum Timing-Advance value (i.e. MS distance) before triggering HO
   default   Use default (9999), remove explicit setting on this node
 
+OsmoBSC(config-net)# handover assignment ?
+  0        Disable in-call assignment
+  1        Enable in-call assignment
+  default  Use default (0), remove explicit setting on this node
+
+OsmoBSC(config-net)# handover tdma-measurement ?
+  full     Full set of 102/104 TDMA frames
+  subset   Sub set of 4 TDMA frames (SACCH)
+  default  Use default (subset), remove explicit setting on this node
+
+OsmoBSC(config-net)# handover min ?
+  rxlev   How weak may RxLev of an MS become before triggering HO
+  rxqual  How bad may RxQual of an MS become before triggering HO
+
+OsmoBSC(config-net)# handover min rxlev ?
+  <-110--50>  minimum RxLev (dBm)
+  default     Use default (-100), remove explicit setting on this node
+
+OsmoBSC(config-net)# handover min rxqual ?
+  <0-7>    minimum RxQual (dBm)
+  default  Use default (5), remove explicit setting on this node
+
+OsmoBSC(config-net)# handover afs-bias ?
+  rxlev   RxLev improvement bias for AFS over other codecs
+  rxqual  RxQual improvement bias for AFS over other codecs
+
+OsmoBSC(config-net)# handover afs-bias rxlev ?
+  <0-20>   Virtual RxLev improvement (dBm)
+  default  Use default (0), remove explicit setting on this node
+
+OsmoBSC(config-net)# handover afs-bias rxqual ?
+  <0-7>    Virtual RxQual improvement (dBm)
+  default  Use default (0), remove explicit setting on this node
+
+OsmoBSC(config-net)# handover min-free-slots ?
+  tch/f  Minimum free TCH/F timeslots before cell is considered congested
+  tch/h  Minimum free TCH/H timeslots before cell is considered congested
+
+OsmoBSC(config-net)# handover min-free-slots tch/f ?
+  <0-9999>  Number of TCH/F slots
+  default   Use default (0), remove explicit setting on this node
+
+OsmoBSC(config-net)# handover min-free-slots TCH/F ?
+% There is no matched command.
+
+OsmoBSC(config-net)# handover min-free-slots tch/h ?
+  <0-9999>  Number of TCH/H slots
+  default   Use default (0), remove explicit setting on this node
+
+OsmoBSC(config-net)# handover max-handovers ?
+  <1-9999>  Number
+  default   Use default (9999), remove explicit setting on this node
+
+OsmoBSC(config-net)# handover penalty-time ?
+  max-distance       Time to suspend handovers after leaving this cell due to exceeding max distance
+  failed-ho          Time to suspend handovers after handover failure to this cell
+  failed-assignment  Time to suspend handovers after assignment failure in this cell
+
+OsmoBSC(config-net)# handover penalty-time max-distance ?
+  <0-99999>  Seconds
+  default    Use default (300), remove explicit setting on this node
+
+OsmoBSC(config-net)# handover penalty-time failed-ho ?
+  <0-99999>  Seconds
+  default    Use default (60), remove explicit setting on this node
+
+OsmoBSC(config-net)# handover penalty-time failed-assignment ?
+  <0-99999>  Seconds
+  default    Use default (60), remove explicit setting on this node
+
+OsmoBSC(config-net)# handover retries ?
+  <0-9>    Number of retries
+  default  Use default (0), remove explicit setting on this node
+
 
 OsmoBSC(config-net)# ### Same on BTS level
 OsmoBSC(config-net)# bts 0
@@ -223,12 +340,26 @@ OsmoBSC(config-net-bts)# handover?
   handover  Handover options
 
 OsmoBSC(config-net-bts)# handover ?
-  0        Disable in-call handover
-  1        Enable in-call handover
-  default  Enable/disable handover: Use default (0), remove explicit setting on this node
-  window   Measurement averaging settings
-  power    Neighbor cell power triggering
-  maximum  Maximum Timing-Advance value (i.e. MS distance) before triggering HO
+  0                 Disable in-call handover
+  1                 Enable in-call handover
+  default           Enable/disable handover: Use default (0), remove explicit setting on this node
+  algorithm         Choose algorithm for handover decision
+  window            Measurement averaging settings
+  power             Neighbor cell power triggering
+  maximum           Maximum Timing-Advance value (i.e. MS distance) before triggering HO
+  assignment        Enable or disable in-call channel re-assignment (HO algo 2 only)
+  tdma-measurement  Define measurement set of TDMA frames (HO algo 2 only)
+  min               Minimum Level/Quality thresholds before triggering HO (HO algo 2 only)
+  afs-bias          Configure bias to prefer AFS (AMR on TCH/F) over other codecs (HO algo 2 only)
+  min-free-slots    Minimum free TCH timeslots before cell is considered congested (HO algo 2 only)
+  max-handovers     Maximum number of concurrent handovers allowed per cell (HO algo 2 only)
+  penalty-time      Set penalty times to wait between repeated handovers (HO algo 2 only)
+  retries           Immediately retry on handover/assignment failure (HO algo 2 only)
+
+OsmoBSC(config-net-bts)# handover algorithm ?
+  1        Algorithm 1: trigger handover based on comparing current cell and neighbor RxLev and RxQual, only.
+  2        Algorithm 2: trigger handover on RxLev/RxQual, and also to balance the load across several cells. Consider available codecs. Prevent repeated handover by penalty timers.
+  default  Use default (1), remove explicit setting on this node
 
 OsmoBSC(config-net-bts)# handover window ?
   rxlev   Received-Level averaging
@@ -277,3 +408,77 @@ OsmoBSC(config-net-bts)# handover maximum ?
 OsmoBSC(config-net-bts)# handover maximum distance ?
   <0-9999>  Maximum Timing-Advance value (i.e. MS distance) before triggering HO
   default   Use default (9999), remove explicit setting on this node
+
+OsmoBSC(config-net-bts)# handover assignment ?
+  0        Disable in-call assignment
+  1        Enable in-call assignment
+  default  Use default (0), remove explicit setting on this node
+
+OsmoBSC(config-net-bts)# handover tdma-measurement ?
+  full     Full set of 102/104 TDMA frames
+  subset   Sub set of 4 TDMA frames (SACCH)
+  default  Use default (subset), remove explicit setting on this node
+
+OsmoBSC(config-net-bts)# handover min ?
+  rxlev   How weak may RxLev of an MS become before triggering HO
+  rxqual  How bad may RxQual of an MS become before triggering HO
+
+OsmoBSC(config-net-bts)# handover min rxlev ?
+  <-110--50>  minimum RxLev (dBm)
+  default     Use default (-100), remove explicit setting on this node
+
+OsmoBSC(config-net-bts)# handover min rxqual ?
+  <0-7>    minimum RxQual (dBm)
+  default  Use default (5), remove explicit setting on this node
+
+OsmoBSC(config-net-bts)# handover afs-bias ?
+  rxlev   RxLev improvement bias for AFS over other codecs
+  rxqual  RxQual improvement bias for AFS over other codecs
+
+OsmoBSC(config-net-bts)# handover afs-bias rxlev ?
+  <0-20>   Virtual RxLev improvement (dBm)
+  default  Use default (0), remove explicit setting on this node
+
+OsmoBSC(config-net-bts)# handover afs-bias rxqual ?
+  <0-7>    Virtual RxQual improvement (dBm)
+  default  Use default (0), remove explicit setting on this node
+
+OsmoBSC(config-net-bts)# handover min-free-slots ?
+  tch/f  Minimum free TCH/F timeslots before cell is considered congested
+  tch/h  Minimum free TCH/H timeslots before cell is considered congested
+
+OsmoBSC(config-net-bts)# handover min-free-slots tch/f ?
+  <0-9999>  Number of TCH/F slots
+  default   Use default (0), remove explicit setting on this node
+
+OsmoBSC(config-net-bts)# handover min-free-slots TCH/F ?
+% There is no matched command.
+
+OsmoBSC(config-net-bts)# handover min-free-slots tch/h ?
+  <0-9999>  Number of TCH/H slots
+  default   Use default (0), remove explicit setting on this node
+
+OsmoBSC(config-net-bts)# handover max-handovers ?
+  <1-9999>  Number
+  default   Use default (9999), remove explicit setting on this node
+
+OsmoBSC(config-net-bts)# handover penalty-time ?
+  max-distance       Time to suspend handovers after leaving this cell due to exceeding max distance
+  failed-ho          Time to suspend handovers after handover failure to this cell
+  failed-assignment  Time to suspend handovers after assignment failure in this cell
+
+OsmoBSC(config-net-bts)# handover penalty-time max-distance ?
+  <0-99999>  Seconds
+  default    Use default (300), remove explicit setting on this node
+
+OsmoBSC(config-net-bts)# handover penalty-time failed-ho ?
+  <0-99999>  Seconds
+  default    Use default (60), remove explicit setting on this node
+
+OsmoBSC(config-net-bts)# handover penalty-time failed-assignment ?
+  <0-99999>  Seconds
+  default    Use default (60), remove explicit setting on this node
+
+OsmoBSC(config-net-bts)# handover retries ?
+  <0-9>    Number of retries
+  default  Use default (0), remove explicit setting on this node