WIP: Initial check-in of a new virtual BTS

1 files changed, 318 insertions, 0 deletions

diff --git a/src/osmo-bts-virtual/l1_if.c b/src/osmo-bts-virtual/l1_if.c
new file mode 100644
index 00000000..0e407bba
--- /dev/null
+++ b/src/osmo-bts-virtual/l1_if.c
@@ -0,0 +1,318 @@
+/* Virtual BTS layer 1 primitive handling and interface
+ *
+ * Copyright (C) 2015 Harald Welte <laforge@gnumonks.org>
+ *
+ * All Rights Reserved
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <stdint.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <errno.h>
+
+#include <osmocom/core/talloc.h>
+#include <osmocom/core/bits.h>
+#include <osmocom/core/linuxlist.h>
+
+#include <osmo-bts/logging.h>
+#include <osmo-bts/bts.h>
+#include <osmo-bts/oml.h>
+#include <osmo-bts/rsl.h>
+#include <osmo-bts/l1sap.h>
+#include <osmo-bts/bts_model.h>
+#include <osmo-bts/phy_link.h>
+#include <osmo-bts/amr.h>
+#include <osmo-bts/abis.h>
+#include <osmo-bts/scheduler.h>
+
+#include "virtual_um.h"
+
+static void virt_um_rcv_cb(struct virt_um_inst *vui, struct msgb *msg)
+{
+	/* FIXME: Handle msg from MS */
+}
+
+
+/* called by common part once OML link is established */
+int bts_model_oml_estab(struct gsm_bts *bts)
+{
+	return 0;
+}
+
+int bts_model_phy_link_open(struct phy_link *plink)
+{
+	struct phy_instance *pinst;
+
+	//OSMO_ASSERT(plink->type == PHY_LINK_T_VIRTUAL);
+
+	if (plink->u.virt.virt_um)
+		virt_um_destroy(plink->u.virt.virt_um);
+
+	phy_link_state_set(plink, PHY_LINK_CONNECTING);
+
+	plink->u.virt.virt_um = virt_um_init(plink, plink->u.virt.mcast_group,
+				      plink->u.virt.mcast_port,
+				      plink->u.virt.mcast_dev, plink,
+				      virt_um_rcv_cb);
+	if (!plink->u.virt.virt_um) {
+		phy_link_state_set(plink, PHY_LINK_SHUTDOWN);
+		return -1;
+	}
+
+	/* iterate over list of PHY instances and initialize the
+	 * scheduler */
+	llist_for_each_entry(pinst, &plink->instances, list) {
+		trx_sched_init(&pinst->u.virt.sched, pinst->trx);
+		if (pinst->trx == pinst->trx->bts->c0)
+			vbts_sched_start(pinst->trx->bts);
+	}
+
+	/* this will automatically update the MO state of all associated
+	 * TRX objects */
+	phy_link_state_set(plink, PHY_LINK_CONNECTED);
+
+	return 0;
+}
+
+
+/*
+ * primitive handling
+ */
+
+/* enable ciphering */
+static int l1if_set_ciphering(struct gsm_lchan *lchan, uint8_t chan_nr, int downlink)
+{
+	struct gsm_bts_trx *trx = lchan->ts->trx;
+	struct phy_instance *pinst = trx_phy_instance(trx);
+	struct l1sched_trx *sched = &pinst->u.virt.sched;
+
+	/* ciphering already enabled in both directions */
+	if (lchan->ciph_state == LCHAN_CIPH_RXTX_CONF)
+		return -EINVAL;
+
+	if (!downlink) {
+		/* set uplink */
+		trx_sched_set_cipher(sched, chan_nr, 0, lchan->encr.alg_id - 1,
+			lchan->encr.key, lchan->encr.key_len);
+		lchan->ciph_state = LCHAN_CIPH_RX_CONF;
+	} else {
+		/* set downlink and also set uplink, if not already */
+		if (lchan->ciph_state != LCHAN_CIPH_RX_CONF) {
+			trx_sched_set_cipher(sched, chan_nr, 0,
+				lchan->encr.alg_id - 1, lchan->encr.key,
+				lchan->encr.key_len);
+		}
+		trx_sched_set_cipher(sched, chan_nr, 1, lchan->encr.alg_id - 1,
+			lchan->encr.key, lchan->encr.key_len);
+		lchan->ciph_state = LCHAN_CIPH_RXTX_CONF;
+	}
+
+	return 0;
+}
+
+static int mph_info_chan_confirm(struct gsm_bts_trx *trx, uint8_t chan_nr,
+	enum osmo_mph_info_type type, uint8_t cause)
+{
+	struct osmo_phsap_prim l1sap;
+
+	memset(&l1sap, 0, sizeof(l1sap));
+	osmo_prim_init(&l1sap.oph, SAP_GSM_PH, PRIM_MPH_INFO, PRIM_OP_CONFIRM,
+		NULL);
+	l1sap.u.info.type = type;
+	l1sap.u.info.u.act_cnf.chan_nr = chan_nr;
+	l1sap.u.info.u.act_cnf.cause = cause;
+
+	return l1sap_up(trx, &l1sap);
+}
+
+int l1if_mph_time_ind(struct gsm_bts *bts, uint32_t fn)
+{
+	struct osmo_phsap_prim l1sap;
+
+	memset(&l1sap, 0, sizeof(l1sap));
+	osmo_prim_init(&l1sap.oph, SAP_GSM_PH, PRIM_MPH_INFO,
+		PRIM_OP_INDICATION, NULL);
+	l1sap.u.info.type = PRIM_INFO_TIME;
+	l1sap.u.info.u.time_ind.fn = fn;
+
+	if (!bts->c0)
+		return -EINVAL;
+
+	return l1sap_up(bts->c0, &l1sap);
+}
+
+
+static void l1if_fill_meas_res(struct osmo_phsap_prim *l1sap, uint8_t chan_nr, float ta,
+				float ber, float rssi)
+{
+	memset(l1sap, 0, sizeof(*l1sap));
+	osmo_prim_init(&l1sap->oph, SAP_GSM_PH, PRIM_MPH_INFO,
+		PRIM_OP_INDICATION, NULL);
+	l1sap->u.info.type = PRIM_INFO_MEAS;
+	l1sap->u.info.u.meas_ind.chan_nr = chan_nr;
+	l1sap->u.info.u.meas_ind.ta_offs_qbits = (int16_t)(ta*4);
+	l1sap->u.info.u.meas_ind.ber10k = (unsigned int) (ber * 10000);
+	l1sap->u.info.u.meas_ind.inv_rssi = (uint8_t) (rssi * -1);
+}
+
+int l1if_process_meas_res(struct gsm_bts_trx *trx, uint8_t tn, uint32_t fn, uint8_t chan_nr,
+	int n_errors, int n_bits_total, float rssi, float toa)
+{
+	struct gsm_lchan *lchan = &trx->ts[tn].lchan[l1sap_chan2ss(chan_nr)];
+	struct osmo_phsap_prim l1sap;
+	/* 100% BER is n_bits_total is 0 */
+	float ber = n_bits_total==0 ? 1.0 : (float)n_errors / (float)n_bits_total;
+
+	LOGP(DMEAS, LOGL_DEBUG, "RX L1 frame %s fn=%u chan_nr=0x%02x MS pwr=%ddBm rssi=%.1f dBFS "
+		"ber=%.2f%% (%d/%d bits) L1_ta=%d rqd_ta=%d toa=%.2f\n",
+		gsm_lchan_name(lchan), fn, chan_nr, ms_pwr_dbm(lchan->ts->trx->bts->band, lchan->ms_power),
+		rssi, ber*100, n_errors, n_bits_total, lchan->meas.l1_info[1], lchan->rqd_ta, toa);
+
+	l1if_fill_meas_res(&l1sap, chan_nr, lchan->rqd_ta + toa, ber, rssi);
+
+	return l1sap_up(trx, &l1sap);
+}
+
+
+
+/* primitive from common part */
+int bts_model_l1sap_down(struct gsm_bts_trx *trx, struct osmo_phsap_prim *l1sap)
+{
+	struct phy_instance *pinst = trx_phy_instance(trx);
+	struct l1sched_trx *sched = &pinst->u.virt.sched;
+	struct msgb *msg = l1sap->oph.msg;
+	uint8_t chan_nr;
+	uint8_t tn, ss;
+	int rc = 0;
+	struct gsm_lchan *lchan;
+
+	switch (OSMO_PRIM_HDR(&l1sap->oph)) {
+	case OSMO_PRIM(PRIM_PH_DATA, PRIM_OP_REQUEST):
+		if (!msg)
+			break;
+		/* put data into scheduler's queue */
+		return trx_sched_ph_data_req(sched, l1sap);
+	case OSMO_PRIM(PRIM_TCH, PRIM_OP_REQUEST):
+		if (!msg)
+			break;
+		/* put data into scheduler's queue */
+		return trx_sched_tch_req(sched, l1sap);
+	case OSMO_PRIM(PRIM_MPH_INFO, PRIM_OP_REQUEST):
+		switch (l1sap->u.info.type) {
+		case PRIM_INFO_ACT_CIPH:
+			chan_nr = l1sap->u.info.u.ciph_req.chan_nr;
+			tn = L1SAP_CHAN2TS(chan_nr);
+			ss = l1sap_chan2ss(chan_nr);
+			lchan = &trx->ts[tn].lchan[ss];
+			if (l1sap->u.info.u.ciph_req.uplink)
+				l1if_set_ciphering(lchan, chan_nr, 0);
+			if (l1sap->u.info.u.ciph_req.downlink)
+				l1if_set_ciphering(lchan, chan_nr, 1);
+			break;
+		case PRIM_INFO_ACTIVATE:
+		case PRIM_INFO_DEACTIVATE:
+		case PRIM_INFO_MODIFY:
+			chan_nr = l1sap->u.info.u.act_req.chan_nr;
+			tn = L1SAP_CHAN2TS(chan_nr);
+			ss = l1sap_chan2ss(chan_nr);
+			lchan = &trx->ts[tn].lchan[ss];
+			if (l1sap->u.info.type == PRIM_INFO_ACTIVATE) {
+				if ((chan_nr & 0x80)) {
+					LOGP(DL1C, LOGL_ERROR, "Cannot activate"
+						" chan_nr 0x%02x\n", chan_nr);
+					break;
+				}
+				/* activate dedicated channel */
+				trx_sched_set_lchan(sched, chan_nr, 0x00, 1);
+				/* activate associated channel */
+				trx_sched_set_lchan(sched, chan_nr, 0x40, 1);
+				/* set mode */
+				trx_sched_set_mode(sched, chan_nr,
+					lchan->rsl_cmode, lchan->tch_mode,
+					lchan->tch.amr_mr.num_modes,
+					lchan->tch.amr_mr.bts_mode[0].mode,
+					lchan->tch.amr_mr.bts_mode[1].mode,
+					lchan->tch.amr_mr.bts_mode[2].mode,
+					lchan->tch.amr_mr.bts_mode[3].mode,
+					amr_get_initial_mode(lchan),
+					(lchan->ho.active == 1));
+				/* init lapdm */
+				lchan_init_lapdm(lchan);
+				/* set lchan active */
+				lchan_set_state(lchan, LCHAN_S_ACTIVE);
+				/* set initial ciphering */
+				l1if_set_ciphering(lchan, chan_nr, 0);
+				l1if_set_ciphering(lchan, chan_nr, 1);
+				if (lchan->encr.alg_id)
+					lchan->ciph_state = LCHAN_CIPH_RXTX_CONF;
+				else
+					lchan->ciph_state = LCHAN_CIPH_NONE;
+
+				/* confirm */
+				mph_info_chan_confirm(trx, chan_nr,
+					PRIM_INFO_ACTIVATE, 0);
+				break;
+			}
+			if (l1sap->u.info.type == PRIM_INFO_MODIFY) {
+				/* change mode */
+				trx_sched_set_mode(sched, chan_nr,
+					lchan->rsl_cmode, lchan->tch_mode,
+					lchan->tch.amr_mr.num_modes,
+					lchan->tch.amr_mr.bts_mode[0].mode,
+					lchan->tch.amr_mr.bts_mode[1].mode,
+					lchan->tch.amr_mr.bts_mode[2].mode,
+					lchan->tch.amr_mr.bts_mode[3].mode,
+					amr_get_initial_mode(lchan),
+					0);
+				break;
+			}
+			if ((chan_nr & 0x80)) {
+				LOGP(DL1C, LOGL_ERROR, "Cannot deactivate "
+					"chan_nr 0x%02x\n", chan_nr);
+				break;
+			}
+			/* deactivate associated channel */
+			trx_sched_set_lchan(sched, chan_nr, 0x40, 0);
+			if (!l1sap->u.info.u.act_req.sacch_only) {
+				/* set lchan inactive */
+				lchan_set_state(lchan, LCHAN_S_NONE);
+				/* deactivate dedicated channel */
+				trx_sched_set_lchan(sched, chan_nr, 0x00, 0);
+				/* confirm only on dedicated channel */
+				mph_info_chan_confirm(trx, chan_nr,
+					PRIM_INFO_DEACTIVATE, 0);
+				lchan->ciph_state = 0; /* FIXME: do this in common/\*.c */
+			}
+			break;
+		default:
+			LOGP(DL1C, LOGL_NOTICE, "unknown MPH-INFO.req %d\n",
+				l1sap->u.info.type);
+			rc = -EINVAL;
+			goto done;
+		}
+		break;
+	default:
+		LOGP(DL1C, LOGL_NOTICE, "unknown prim %d op %d\n",
+			l1sap->oph.primitive, l1sap->oph.operation);
+		rc = -EINVAL;
+		goto done;
+	}
+
+done:
+	if (msg)
+		msgb_free(msg);
+	return rc;
+}