shutdown_fsm: Add power_ramp_force() to jump straight to the tgt power

Both power_ramp_start() and power_ramp_force() are now small macros
around _power_ramp_start()

The new behavior is:
* ramp down power when stopping bts through Ctrl-C
* the other shutdown causes skip power ramping

This will cause the bts to reconnect faster when the oml link is
dropped and power ramping is enabled.

Change-Id: Ida1d7bbf094958b9142af306dbf84206729a609e
Related: SYS#6237

include/osmo-bts/bts.h

@@ -374,6 +374,7 @@ struct gsm_bts {
 
 	struct osmo_fsm_inst *shutdown_fi; /* FSM instance to manage shutdown procedure during process exit */
 	bool shutdown_fi_exit_proc; /* exit process when shutdown_fsm is finished? */
+	bool shutdown_fi_skip_power_ramp; /* Skip power ramping and change power in one step? */
 	struct osmo_fsm_inst *abis_link_fi; /* FSM instance to manage abis connection during process startup and link failure */
 	struct osmo_tdef *T_defs; /* Timer defines */
 
@@ -396,7 +397,7 @@ struct gsm_bts *gsm_bts_num(const struct gsm_network *net, int num);
 
 int bts_init(struct gsm_bts *bts);
 void bts_shutdown(struct gsm_bts *bts, const char *reason);
-void bts_shutdown_ext(struct gsm_bts *bts, const char *reason, bool exit_proc);
+void bts_shutdown_ext(struct gsm_bts *bts, const char *reason, bool exit_proc, bool skip_power_ramp);
 
 int bts_link_estab(struct gsm_bts *bts);
 

include/osmo-bts/tx_power.h

@@ -77,7 +77,12 @@ int get_p_trxout_target_mdBm_lchan(const struct gsm_lchan *lchan);
 int get_p_trxout_actual_mdBm(const struct gsm_bts_trx *trx, uint8_t bs_power_red);
 int get_p_trxout_actual_mdBm_lchan(const struct gsm_lchan *lchan);
 
-int power_ramp_start(struct gsm_bts_trx *trx, int p_total_tgt_mdBm, int bypass, ramp_compl_cb_t ramp_compl_cb);
+int _power_ramp_start(struct gsm_bts_trx *trx, int p_total_tgt_mdBm, int bypass_max_power, ramp_compl_cb_t ramp_compl_cb, bool skip_ramping);
+#define power_ramp_start(trx, p_total_tgt_mdBm, bypass_max_power, ramp_compl_cb) \
+	_power_ramp_start(trx, p_total_tgt_mdBm, bypass_max_power, ramp_compl_cb, false)
+#define power_ramp_force(trx, p_total_tgt_mdBm, bypass_max_power, ramp_compl_cb) \
+	_power_ramp_start(trx, p_total_tgt_mdBm, bypass_max_power, ramp_compl_cb, true)
+
 void power_ramp_abort(struct gsm_bts_trx *trx);
 
 void power_trx_change_compl(struct gsm_bts_trx *trx, int p_trxout_cur_mdBm);

src/common/bts_shutdown_fsm.c

@@ -89,7 +89,10 @@ static void st_wait_ramp_down_compl_on_enter(struct osmo_fsm_inst *fi, uint32_t
 	llist_for_each_entry(trx, &bts->trx_list, list) {
 		if (trx->mo.nm_state.operational != NM_OPSTATE_ENABLED)
 			continue;
-		power_ramp_start(trx, to_mdB(BTS_SHUTDOWN_POWER_RAMP_TGT), 1, ramp_down_compl_cb);
+		if (bts->shutdown_fi_skip_power_ramp)
+			power_ramp_force(trx, to_mdB(BTS_SHUTDOWN_POWER_RAMP_TGT), 1, ramp_down_compl_cb);
+		else
+			power_ramp_start(trx, to_mdB(BTS_SHUTDOWN_POWER_RAMP_TGT), 1, ramp_down_compl_cb);
 	}
 }
 
@@ -250,7 +253,7 @@ bool bts_shutdown_in_progress(const struct gsm_bts *bts)
 	return fi->state != BTS_SHUTDOWN_ST_NONE;
 }
 
-void bts_shutdown_ext(struct gsm_bts *bts, const char *reason, bool exit_proc)
+void bts_shutdown_ext(struct gsm_bts *bts, const char *reason, bool exit_proc, bool skip_power_ramp)
 {
 	struct osmo_fsm_inst *fi = bts->shutdown_fi;
 	if (bts_shutdown_in_progress(bts)) {
@@ -260,6 +263,7 @@ void bts_shutdown_ext(struct gsm_bts *bts, const char *reason, bool exit_proc)
 		return;
 	}
 	bts->shutdown_fi_exit_proc = exit_proc;
+	bts->shutdown_fi_skip_power_ramp = skip_power_ramp;
 	LOGPFSML(fi, LOGL_NOTICE, "Shutting down BTS, exit %u, reason: %s\n",
 		 exit_proc, reason);
 	osmo_fsm_inst_dispatch(fi, BTS_SHUTDOWN_EV_START, NULL);
@@ -267,7 +271,7 @@ void bts_shutdown_ext(struct gsm_bts *bts, const char *reason, bool exit_proc)
 
 void bts_shutdown(struct gsm_bts *bts, const char *reason)
 {
-	bts_shutdown_ext(bts, reason, true);
+	bts_shutdown_ext(bts, reason, true, true);
 }
 
 void bts_model_trx_close_cb(struct gsm_bts_trx *trx, int rc)

src/common/main.c

@@ -233,7 +233,7 @@ static void signal_handler(int signum)
 			oml_tx_failure_event_rep(&g_bts->mo,
 						 NM_SEVER_CRITICAL, OSMO_EVT_CRIT_PROC_STOP,
 						 "BTS: SIGINT received -> shutdown");
-			bts_shutdown(g_bts, "SIGINT");
+			bts_shutdown_ext(g_bts, "SIGINT", true, false);
 		}
 		quit++;
 		break;

src/common/tx_power.c

@@ -239,8 +239,7 @@ static void power_ramp_do_step(struct gsm_bts_trx *trx, int first)
 	osmo_timer_schedule(&tpp->ramp.step_timer, tpp->ramp.step_interval_sec, 0);
 }
 
-
-int power_ramp_start(struct gsm_bts_trx *trx, int p_total_tgt_mdBm, int bypass, ramp_compl_cb_t ramp_compl_cb)
+int _power_ramp_start(struct gsm_bts_trx *trx, int p_total_tgt_mdBm, int bypass, ramp_compl_cb_t ramp_compl_cb, bool skip_ramping)
 {
 	struct trx_power_params *tpp = &trx->power_params;
 
@@ -265,7 +264,12 @@ int power_ramp_start(struct gsm_bts_trx *trx, int p_total_tgt_mdBm, int bypass,
 	tpp->p_total_tgt_mdBm = p_total_tgt_mdBm;
 	tpp->ramp.compl_cb = ramp_compl_cb;
 
-	if (we_are_ramping_up(trx)) {
+	if (skip_ramping) {
+		/* Jump straight to the target power */
+		tpp->p_total_cur_mdBm = p_total_tgt_mdBm;
+		tpp->ramp.attenuation_mdB = 0;
+		power_ramp_timer_cb(trx);
+	} else if (we_are_ramping_up(trx)) {
 		if (tpp->p_total_tgt_mdBm <= tpp->ramp.max_initial_pout_mdBm) {
 			LOGPTRX(trx, DL1C, LOGL_INFO,
 				"target_power (%d mdBm) is below or equal to 'power ramp max-initial' power (%d mdBm)\n",

src/osmo-bts-trx/l1_if.c

@@ -195,7 +195,7 @@ void bts_model_abis_close(struct gsm_bts *bts)
 {
 	/* Go into shutdown state deactivating transceivers until Abis link
 	 * becomes up again */
-	bts_shutdown_ext(bts, "Abis close", false);
+	bts_shutdown_ext(bts, "Abis close", false, true);
 }
 
 int bts_model_adjst_ms_pwr(struct gsm_lchan *lchan)