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-rw-r--r--src/osmo-bts-oc2g/tch.c545
1 files changed, 545 insertions, 0 deletions
diff --git a/src/osmo-bts-oc2g/tch.c b/src/osmo-bts-oc2g/tch.c
new file mode 100644
index 00000000..1bd93e4b
--- /dev/null
+++ b/src/osmo-bts-oc2g/tch.c
@@ -0,0 +1,545 @@
+/* Traffic channel support for NuRAN Wireless OC-2G BTS L1 */
+
+/* Copyright (C) 2015 by Yves Godin <support@nuranwireless.com>
+ *
+ * Based on sysmoBTS:
+ * (C) 2011-2012 by 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 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 <errno.h>
+#include <fcntl.h>
+#include <stdbool.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+
+#include <osmocom/core/talloc.h>
+#include <osmocom/core/utils.h>
+#include <osmocom/core/select.h>
+#include <osmocom/core/timer.h>
+#include <osmocom/core/bits.h>
+#include <osmocom/gsm/gsm_utils.h>
+
+#include <osmo-bts/logging.h>
+#include <osmo-bts/bts.h>
+#include <osmo-bts/gsm_data.h>
+#include <osmo-bts/msg_utils.h>
+#include <osmo-bts/measurement.h>
+#include <osmo-bts/amr.h>
+#include <osmo-bts/l1sap.h>
+#include <osmo-bts/dtx_dl_amr_fsm.h>
+
+#include <nrw/oc2g/oc2g.h>
+#include <nrw/oc2g/gsml1prim.h>
+#include <nrw/oc2g/gsml1const.h>
+#include <nrw/oc2g/gsml1types.h>
+
+#include "oc2gbts.h"
+#include "l1_if.h"
+
+static struct msgb *l1_to_rtppayload_fr(uint8_t *l1_payload, uint8_t payload_len,
+ struct gsm_lchan *lchan)
+{
+ struct msgb *msg;
+ uint8_t *cur;
+
+ msg = msgb_alloc_headroom(1024, 128, "L1P-to-RTP");
+ if (!msg)
+ return NULL;
+
+ /* new L1 can deliver bits like we need them */
+ cur = msgb_put(msg, GSM_FR_BYTES);
+ memcpy(cur, l1_payload, GSM_FR_BYTES);
+
+ lchan_set_marker(osmo_fr_check_sid(l1_payload, payload_len), lchan);
+
+ return msg;
+}
+
+/*! \brief convert GSM-FR from RTP payload to L1 format
+ * \param[out] l1_payload payload part of L1 buffer
+ * \param[in] rtp_payload pointer to RTP payload data
+ * \param[in] payload_len length of \a rtp_payload
+ * \returns number of \a l1_payload bytes filled
+ */
+static int rtppayload_to_l1_fr(uint8_t *l1_payload, const uint8_t *rtp_payload,
+ unsigned int payload_len)
+{
+ /* new L1 can deliver bits like we need them */
+ memcpy(l1_payload, rtp_payload, GSM_FR_BYTES);
+ return GSM_FR_BYTES;
+}
+
+static struct msgb *l1_to_rtppayload_efr(uint8_t *l1_payload,
+ uint8_t payload_len,
+ struct gsm_lchan *lchan)
+{
+ struct msgb *msg;
+ uint8_t *cur;
+
+ msg = msgb_alloc_headroom(1024, 128, "L1P-to-RTP");
+ if (!msg)
+ return NULL;
+
+ /* new L1 can deliver bits like we need them */
+ cur = msgb_put(msg, GSM_EFR_BYTES);
+ memcpy(cur, l1_payload, GSM_EFR_BYTES);
+ enum osmo_amr_type ft;
+ enum osmo_amr_quality bfi;
+ uint8_t cmr;
+ int8_t sti, cmi;
+ osmo_amr_rtp_dec(l1_payload, payload_len, &cmr, &cmi, &ft, &bfi, &sti);
+ lchan_set_marker(ft == AMR_GSM_EFR_SID, lchan);
+
+ return msg;
+}
+
+static int rtppayload_to_l1_efr(uint8_t *l1_payload, const uint8_t *rtp_payload,
+ unsigned int payload_len)
+{
+ memcpy(l1_payload, rtp_payload, payload_len);
+
+ return payload_len;
+}
+
+static struct msgb *l1_to_rtppayload_hr(uint8_t *l1_payload, uint8_t payload_len,
+ struct gsm_lchan *lchan)
+{
+ struct msgb *msg;
+ uint8_t *cur;
+
+ msg = msgb_alloc_headroom(1024, 128, "L1P-to-RTP");
+ if (!msg)
+ return NULL;
+
+ if (payload_len != GSM_HR_BYTES) {
+ LOGP(DL1P, LOGL_ERROR, "L1 HR frame length %u != expected %u\n",
+ payload_len, GSM_HR_BYTES);
+ return NULL;
+ }
+
+ cur = msgb_put(msg, GSM_HR_BYTES);
+ memcpy(cur, l1_payload, GSM_HR_BYTES);
+
+ lchan_set_marker(osmo_hr_check_sid(l1_payload, payload_len), lchan);
+
+ return msg;
+}
+
+/*! \brief convert GSM-FR from RTP payload to L1 format
+ * \param[out] l1_payload payload part of L1 buffer
+ * \param[in] rtp_payload pointer to RTP payload data
+ * \param[in] payload_len length of \a rtp_payload
+ * \returns number of \a l1_payload bytes filled
+ */
+static int rtppayload_to_l1_hr(uint8_t *l1_payload, const uint8_t *rtp_payload,
+ unsigned int payload_len)
+{
+
+ if (payload_len != GSM_HR_BYTES) {
+ LOGP(DL1P, LOGL_ERROR, "RTP HR frame length %u != expected %u\n",
+ payload_len, GSM_HR_BYTES);
+ return 0;
+ }
+
+ memcpy(l1_payload, rtp_payload, GSM_HR_BYTES);
+
+ return GSM_HR_BYTES;
+}
+
+static struct msgb *l1_to_rtppayload_amr(uint8_t *l1_payload, uint8_t payload_len,
+ struct gsm_lchan *lchan)
+{
+ struct msgb *msg;
+ uint8_t amr_if2_len = payload_len - 2;
+ uint8_t *cur;
+
+ msg = msgb_alloc_headroom(1024, 128, "L1P-to-RTP");
+ if (!msg)
+ return NULL;
+
+ cur = msgb_put(msg, amr_if2_len);
+ memcpy(cur, l1_payload+2, amr_if2_len);
+
+ /*
+ * Audiocode's MGW doesn't like receiving CMRs that are not
+ * the same as the previous one. This means we need to patch
+ * the content here.
+ */
+ if ((cur[0] & 0xF0) == 0xF0)
+ cur[0]= lchan->tch.last_cmr << 4;
+ else
+ lchan->tch.last_cmr = cur[0] >> 4;
+
+ return msg;
+}
+
+/*! \brief convert AMR from RTP payload to L1 format
+ * \param[out] l1_payload payload part of L1 buffer
+ * \param[in] rtp_payload pointer to RTP payload data
+ * \param[in] payload_len length of \a rtp_payload
+ * \returns number of \a l1_payload bytes filled
+ */
+static int rtppayload_to_l1_amr(uint8_t *l1_payload, const uint8_t *rtp_payload,
+ uint8_t payload_len, uint8_t ft)
+{
+ memcpy(l1_payload, rtp_payload, payload_len);
+ return payload_len;
+}
+
+#define RTP_MSGB_ALLOC_SIZE 512
+
+/*! \brief function for incoming RTP via TCH.req
+ * \param[in] rtp_pl buffer containing RTP payload
+ * \param[in] rtp_pl_len length of \a rtp_pl
+ * \param[in] use_cache Use cached payload instead of parsing RTP
+ * \param[in] marker RTP header Marker bit (indicates speech onset)
+ * \returns 0 if encoding result can be sent further to L1 without extra actions
+ * positive value if data is ready AND extra actions are required
+ * negative value otherwise (no data for L1 encoded)
+ *
+ * This function prepares a msgb with a L1 PH-DATA.req primitive and
+ * queues it into lchan->dl_tch_queue.
+ *
+ * Note that the actual L1 primitive header is not fully initialized
+ * yet, as things like the frame number, etc. are unknown at the time we
+ * pre-fill the primtive.
+ */
+int l1if_tch_encode(struct gsm_lchan *lchan, uint8_t *data, uint8_t *len,
+ const uint8_t *rtp_pl, unsigned int rtp_pl_len, uint32_t fn,
+ bool use_cache, bool marker)
+{
+ uint8_t *payload_type;
+ uint8_t *l1_payload, ft;
+ int rc = 0;
+ bool is_sid = false;
+
+ DEBUGP(DRTP, "%s RTP IN: %s\n", gsm_lchan_name(lchan),
+ osmo_hexdump(rtp_pl, rtp_pl_len));
+
+ payload_type = &data[0];
+ l1_payload = &data[1];
+
+ switch (lchan->tch_mode) {
+ case GSM48_CMODE_SPEECH_V1:
+ if (lchan->type == GSM_LCHAN_TCH_F) {
+ *payload_type = GsmL1_TchPlType_Fr;
+ rc = rtppayload_to_l1_fr(l1_payload,
+ rtp_pl, rtp_pl_len);
+ if (rc && lchan->ts->trx->bts->dtxd)
+ is_sid = osmo_fr_check_sid(rtp_pl, rtp_pl_len);
+ } else{
+ *payload_type = GsmL1_TchPlType_Hr;
+ rc = rtppayload_to_l1_hr(l1_payload,
+ rtp_pl, rtp_pl_len);
+ if (rc && lchan->ts->trx->bts->dtxd)
+ is_sid = osmo_hr_check_sid(rtp_pl, rtp_pl_len);
+ }
+ if (is_sid)
+ dtx_cache_payload(lchan, rtp_pl, rtp_pl_len, fn, -1);
+ break;
+ case GSM48_CMODE_SPEECH_EFR:
+ *payload_type = GsmL1_TchPlType_Efr;
+ rc = rtppayload_to_l1_efr(l1_payload, rtp_pl,
+ rtp_pl_len);
+ /* FIXME: detect and save EFR SID */
+ break;
+ case GSM48_CMODE_SPEECH_AMR:
+ if (use_cache) {
+ *payload_type = GsmL1_TchPlType_Amr;
+ rtppayload_to_l1_amr(l1_payload, lchan->tch.dtx.cache,
+ lchan->tch.dtx.len, ft);
+ *len = lchan->tch.dtx.len + 1;
+ return 0;
+ }
+
+ rc = dtx_dl_amr_fsm_step(lchan, rtp_pl, rtp_pl_len, fn,
+ l1_payload, marker, len, &ft);
+ if (rc < 0)
+ return rc;
+ if (!dtx_dl_amr_enabled(lchan)) {
+ *payload_type = GsmL1_TchPlType_Amr;
+ rtppayload_to_l1_amr(l1_payload + 2, rtp_pl, rtp_pl_len,
+ ft);
+ return 0;
+ }
+
+ /* DTX DL-specific logic below: */
+ switch (lchan->tch.dtx.dl_amr_fsm->state) {
+ case ST_ONSET_V:
+ *payload_type = GsmL1_TchPlType_Amr_Onset;
+ dtx_cache_payload(lchan, rtp_pl, rtp_pl_len, fn, 0);
+ *len = 3;
+ return 1;
+ case ST_VOICE:
+ *payload_type = GsmL1_TchPlType_Amr;
+ rtppayload_to_l1_amr(l1_payload + 2, rtp_pl, rtp_pl_len,
+ ft);
+ return 0;
+ case ST_SID_F1:
+ if (lchan->type == GSM_LCHAN_TCH_H) { /* AMR HR */
+ *payload_type = GsmL1_TchPlType_Amr_SidFirstP1;
+ rtppayload_to_l1_amr(l1_payload + 2, rtp_pl,
+ rtp_pl_len, ft);
+ return 0;
+ }
+ /* AMR FR */
+ *payload_type = GsmL1_TchPlType_Amr;
+ rtppayload_to_l1_amr(l1_payload + 2, rtp_pl, rtp_pl_len,
+ ft);
+ return 0;
+ case ST_SID_F2:
+ *payload_type = GsmL1_TchPlType_Amr;
+ rtppayload_to_l1_amr(l1_payload + 2, rtp_pl, rtp_pl_len,
+ ft);
+ return 0;
+ case ST_F1_INH_V:
+ *payload_type = GsmL1_TchPlType_Amr_SidFirstInH;
+ *len = 3;
+ dtx_cache_payload(lchan, rtp_pl, rtp_pl_len, fn, 0);
+ return 1;
+ case ST_U_INH_V:
+ *payload_type = GsmL1_TchPlType_Amr_SidUpdateInH;
+ *len = 3;
+ dtx_cache_payload(lchan, rtp_pl, rtp_pl_len, fn, 0);
+ return 1;
+ case ST_SID_U:
+ case ST_U_NOINH:
+ return -EAGAIN;
+ case ST_FACCH:
+ return -EBADMSG;
+ default:
+ LOGP(DRTP, LOGL_ERROR, "Unhandled DTX DL AMR FSM state "
+ "%d\n", lchan->tch.dtx.dl_amr_fsm->state);
+ return -EINVAL;
+ }
+ break;
+ default:
+ /* we don't support CSD modes */
+ rc = -1;
+ break;
+ }
+
+ if (rc < 0) {
+ LOGP(DRTP, LOGL_ERROR, "%s unable to parse RTP payload\n",
+ gsm_lchan_name(lchan));
+ return -EBADMSG;
+ }
+
+ *len = rc + 1;
+
+ DEBUGP(DRTP, "%s RTP->L1: %s\n", gsm_lchan_name(lchan),
+ osmo_hexdump(data, *len));
+ return 0;
+}
+
+static int is_recv_only(uint8_t speech_mode)
+{
+ return (speech_mode & 0xF0) == (1 << 4);
+}
+
+/*! \brief receive a traffic L1 primitive for a given lchan */
+int l1if_tch_rx(struct gsm_bts_trx *trx, uint8_t chan_nr, struct msgb *l1p_msg)
+{
+ GsmL1_Prim_t *l1p = msgb_l1prim(l1p_msg);
+ GsmL1_PhDataInd_t *data_ind = &l1p->u.phDataInd;
+ uint8_t *payload, payload_type, payload_len, sid_first[9] = { 0 };
+ struct msgb *rmsg = NULL;
+ struct gsm_lchan *lchan = &trx->ts[L1SAP_CHAN2TS(chan_nr)].lchan[l1sap_chan2ss(chan_nr)];
+
+ if (is_recv_only(lchan->abis_ip.speech_mode))
+ return -EAGAIN;
+
+ if (data_ind->msgUnitParam.u8Size < 1) {
+ LOGPFN(DL1P, LOGL_DEBUG, data_ind->u32Fn, "chan_nr %d Rx Payload size 0\n", chan_nr);
+ /* Push empty payload to upper layers */
+ rmsg = msgb_alloc_headroom(256, 128, "L1P-to-RTP");
+ return add_l1sap_header(trx, rmsg, lchan, chan_nr, data_ind->u32Fn,
+ data_ind->measParam.fBer * 10000,
+ data_ind->measParam.fLinkQuality * 10);
+ }
+
+ payload_type = data_ind->msgUnitParam.u8Buffer[0];
+ payload = data_ind->msgUnitParam.u8Buffer + 1;
+ payload_len = data_ind->msgUnitParam.u8Size - 1;
+
+ /* clear RTP marker if the marker has previously sent */
+ if (!lchan->tch.dtx.is_speech_resume)
+ lchan->rtp_tx_marker = false;
+
+ switch (payload_type) {
+ case GsmL1_TchPlType_Fr:
+ case GsmL1_TchPlType_Efr:
+ if (lchan->type != GSM_LCHAN_TCH_F)
+ goto err_payload_match;
+ break;
+ case GsmL1_TchPlType_Hr:
+ if (lchan->type != GSM_LCHAN_TCH_H)
+ goto err_payload_match;
+ break;
+ case GsmL1_TchPlType_Amr:
+ if (lchan->type != GSM_LCHAN_TCH_H &&
+ lchan->type != GSM_LCHAN_TCH_F)
+ goto err_payload_match;
+ break;
+ case GsmL1_TchPlType_Amr_Onset:
+ if (lchan->type != GSM_LCHAN_TCH_H &&
+ lchan->type != GSM_LCHAN_TCH_F)
+ goto err_payload_match;
+ /* according to 3GPP TS 26.093 ONSET frames precede the first
+ speech frame of a speech burst - set the marker for next RTP
+ frame */
+ lchan->tch.dtx.is_speech_resume = true;
+ lchan->rtp_tx_marker = true;
+ break;
+ case GsmL1_TchPlType_Amr_SidFirstP1:
+ if (lchan->type != GSM_LCHAN_TCH_H)
+ goto err_payload_match;
+ LOGPFN(DL1P, LOGL_DEBUG, data_ind->u32Fn, "DTX: received SID_FIRST_P1 from L1 "
+ "(%d bytes)\n", payload_len);
+ break;
+ case GsmL1_TchPlType_Amr_SidFirstP2:
+ if (lchan->type != GSM_LCHAN_TCH_H)
+ goto err_payload_match;
+ LOGPFN(DL1P, LOGL_DEBUG, data_ind->u32Fn, "DTX: received SID_FIRST_P2 from L1 "
+ "(%d bytes)\n", payload_len);
+ break;
+ case GsmL1_TchPlType_Amr_SidFirstInH:
+ if (lchan->type != GSM_LCHAN_TCH_H)
+ goto err_payload_match;
+ lchan->tch.dtx.is_speech_resume = true;
+ lchan->rtp_tx_marker = true;
+ LOGPFN(DL1P, LOGL_DEBUG, data_ind->u32Fn, "DTX: received SID_FIRST_INH from L1 "
+ "(%d bytes)\n", payload_len);
+ break;
+ case GsmL1_TchPlType_Amr_SidUpdateInH:
+ if (lchan->type != GSM_LCHAN_TCH_H)
+ goto err_payload_match;
+ lchan->tch.dtx.is_speech_resume = true;
+ lchan->rtp_tx_marker = true;
+ LOGPFN(DL1P, LOGL_DEBUG, data_ind->u32Fn, "DTX: received SID_UPDATE_INH from L1 "
+ "(%d bytes)\n", payload_len);
+ break;
+ default:
+ LOGPFN(DL1P, LOGL_NOTICE, data_ind->u32Fn, "%s Rx Payload Type %s is unsupported\n",
+ gsm_lchan_name(lchan),
+ get_value_string(oc2gbts_tch_pl_names, payload_type));
+ break;
+ }
+
+ LOGP(DL1P, LOGL_DEBUG, "%s %s lchan->rtp_tx_marker = %s, len=%u\n",
+ gsm_lchan_name(lchan),
+ get_value_string(oc2gbts_tch_pl_names, payload_type),
+ lchan->rtp_tx_marker ? "true" : "false",
+ payload_len);
+
+ switch (payload_type) {
+ case GsmL1_TchPlType_Fr:
+ rmsg = l1_to_rtppayload_fr(payload, payload_len, lchan);
+ break;
+ case GsmL1_TchPlType_Hr:
+ rmsg = l1_to_rtppayload_hr(payload, payload_len, lchan);
+ break;
+ case GsmL1_TchPlType_Efr:
+ rmsg = l1_to_rtppayload_efr(payload, payload_len, lchan);
+ break;
+ case GsmL1_TchPlType_Amr:
+ rmsg = l1_to_rtppayload_amr(payload, payload_len, lchan);
+ break;
+ case GsmL1_TchPlType_Amr_SidFirstP1:
+ memcpy(sid_first, payload, payload_len);
+ int len = osmo_amr_rtp_enc(sid_first, 0, AMR_SID, AMR_GOOD);
+ if (len < 0)
+ return 0;
+ rmsg = l1_to_rtppayload_amr(sid_first, len, lchan);
+ break;
+ }
+
+ if (rmsg)
+ return add_l1sap_header(trx, rmsg, lchan, chan_nr, data_ind->u32Fn,
+ data_ind->measParam.fBer * 10000,
+ data_ind->measParam.fLinkQuality * 10);
+
+ return 0;
+
+err_payload_match:
+ LOGPFN(DL1P, LOGL_ERROR, data_ind->u32Fn, "%s Rx Payload Type %s incompatible with lchan\n",
+ gsm_lchan_name(lchan), get_value_string(oc2gbts_tch_pl_names, payload_type));
+ return -EINVAL;
+}
+
+struct msgb *gen_empty_tch_msg(struct gsm_lchan *lchan, uint32_t fn)
+{
+ struct msgb *msg;
+ GsmL1_Prim_t *l1p;
+ GsmL1_PhDataReq_t *data_req;
+ GsmL1_MsgUnitParam_t *msu_param;
+ uint8_t *payload_type;
+ uint8_t *l1_payload;
+ int rc;
+
+ msg = l1p_msgb_alloc();
+ if (!msg)
+ return NULL;
+
+ l1p = msgb_l1prim(msg);
+ data_req = &l1p->u.phDataReq;
+ msu_param = &data_req->msgUnitParam;
+ payload_type = &msu_param->u8Buffer[0];
+ l1_payload = &msu_param->u8Buffer[1];
+
+ switch (lchan->tch_mode) {
+ case GSM48_CMODE_SPEECH_AMR:
+ if (lchan->type == GSM_LCHAN_TCH_H &&
+ dtx_dl_amr_enabled(lchan)) {
+ /* we have to explicitly handle sending SID FIRST P2 for
+ AMR HR in here */
+ *payload_type = GsmL1_TchPlType_Amr_SidFirstP2;
+ rc = dtx_dl_amr_fsm_step(lchan, NULL, 0, fn, l1_payload,
+ false, &(msu_param->u8Size),
+ NULL);
+ if (rc == 0)
+ return msg;
+ }
+ *payload_type = GsmL1_TchPlType_Amr;
+ break;
+ case GSM48_CMODE_SPEECH_V1:
+ if (lchan->type == GSM_LCHAN_TCH_F)
+ *payload_type = GsmL1_TchPlType_Fr;
+ else
+ *payload_type = GsmL1_TchPlType_Hr;
+ break;
+ case GSM48_CMODE_SPEECH_EFR:
+ *payload_type = GsmL1_TchPlType_Efr;
+ break;
+ default:
+ msgb_free(msg);
+ return NULL;
+ }
+
+ rc = repeat_last_sid(lchan, l1_payload, fn);
+ if (!rc) {
+ msgb_free(msg);
+ return NULL;
+ }
+ msu_param->u8Size = rc;
+
+ return msg;
+}