[WIP] Split of L1CTL and L1IF

8 files changed, 485 insertions, 268 deletions

diff --git a/include/osmo-bts/gsm_data.h b/include/osmo-bts/gsm_data.h
index c75d726d..a3ae30f4 100644
--- a/include/osmo-bts/gsm_data.h
+++ b/include/osmo-bts/gsm_data.h
@@ -58,9 +58,9 @@ static inline struct femtol1_hdl *trx_femtol1_hdl(struct gsm_bts_trx *trx)
 	return trx->role_bts.l1h;
 }
 
-struct bbl1_hdl;
+struct osmo_l1_if;
 
-static inline struct bbl1_hdl *trx_bbl1_hdl(struct gsm_bts_trx *trx)
+static inline struct osmo_l1_if *trx_l1_if(struct gsm_bts_trx *trx)
 {
 	return trx->role_bts.l1h;
 }
diff --git a/src/osmo-bts-bb/Makefile.am b/src/osmo-bts-bb/Makefile.am
index c922fd22..f8791365 100644
--- a/src/osmo-bts-bb/Makefile.am
+++ b/src/osmo-bts-bb/Makefile.am
@@ -4,5 +4,5 @@ LDADD = $(LIBOSMOCORE_LIBS) $(LIBOSMOGSM_LIBS) $(LIBOSMOVTY_LIBS)
 
 bin_PROGRAMS = osmobts
 
-osmobts_SOURCES = main.c oml.c bts_model.c l1_if.c
+osmobts_SOURCES = main.c oml.c bts_model.c l1_if.c l1ctl.c
 osmobts_LDADD = $(top_builddir)/src/common/libbts.a $(LDADD)
diff --git a/src/osmo-bts-bb/l1_if.c b/src/osmo-bts-bb/l1_if.c
index d3f6a69f..77cccac3 100644
--- a/src/osmo-bts-bb/l1_if.c
+++ b/src/osmo-bts-bb/l1_if.c
@@ -1,8 +1,6 @@
 /* Interface to layer 1 of baseband */
 
-/* (C) 2010 by Holger Hans Peter Freyther
- * (C) 2010 by Harald Welte <laforge@gnumonks.org>
- * (C) 2011 by Andreas Eversberg <jolly@eversberg.eu>
+/* (C) 2011 by Andreas Eversberg <jolly@eversberg.eu>
  *
  * All Rights Reserved
  *
@@ -47,167 +45,16 @@
 #include <osmo-bts/gsm_data.h>
 #include <osmo-bts/signal.h>
 
+#include "l1ctl.h"
 #include "l1_if.h"
 #include "oml.h"
 
-uint16_t ref_arfcn;
 extern int tx_only;
 
-/*
- * socket communication with baseband
- */
-
-#include "../../osmocom-bb/include/l1ctl_proto.h"
-
-#define GSM_L2_LENGTH 256
-#define GSM_L2_HEADROOM 32
-
-static int l1if_recv(struct osmo_l1l2_if *l1l2if, struct msgb *msg);
-static int layer2_close(struct osmo_l1l2_if *l1l2if);
-
-static int layer2_read(struct osmo_fd *fd)
-{
-	struct msgb *msg;
-	u_int16_t len;
-	int rc;
-
-	msg = msgb_alloc_headroom(GSM_L2_LENGTH+GSM_L2_HEADROOM, GSM_L2_HEADROOM, "Layer2");
-	if (!msg) {
-		LOGP(DL1C, LOGL_ERROR, "Failed to allocate msg.\n");
-		return -ENOMEM;
-	}
-
-	rc = read(fd->fd, &len, sizeof(len));
-	if (rc < sizeof(len)) {
-		fprintf(stderr, "Layer2 socket failed\n");
-		msgb_free(msg);
-		if (rc >= 0)
-			rc = -EIO;
-		layer2_close((struct osmo_l1l2_if *) fd->data);
-		return rc;
-	}
-
-	len = ntohs(len);
-	if (len > GSM_L2_LENGTH) {
-		LOGP(DL1C, LOGL_ERROR, "Length is too big: %u\n", len);
-		msgb_free(msg);
-		return -EINVAL;
-	}
-
-
-	msg->l1h = msgb_put(msg, len);
-	rc = read(fd->fd, msg->l1h, msgb_l1len(msg));
-	if (rc != msgb_l1len(msg)) {
-		LOGP(DL1C, LOGL_ERROR, "Can not read data: len=%d rc=%d "
-		     "errno=%d\n", len, rc, errno);
-		msgb_free(msg);
-		return rc;
-	}
-
-	l1if_recv((struct osmo_l1l2_if *) fd->data, msg);
-
-	return 0;
-}
-
-static int layer2_write(struct osmo_fd *fd, struct msgb *msg)
-{
-	int rc;
-
-	if (fd->fd <= 0)
-		return -EINVAL;
-
-	rc = write(fd->fd, msg->data, msg->len);
-	if (rc != msg->len) {
-		LOGP(DL1C, LOGL_ERROR, "Failed to write data: rc: %d\n", rc);
-		return rc;
-	}
-
-	return 0;
-}
-
-static int layer2_open(struct osmo_l1l2_if *l1l2if, const char *socket_path)
-{
-	int rc;
-	struct sockaddr_un local;
-
-	l1l2if->l2_wq.bfd.fd = socket(AF_UNIX, SOCK_STREAM, 0);
-	if (l1l2if->l2_wq.bfd.fd < 0) {
-		fprintf(stderr, "Failed to create unix domain socket.\n");
-		return l1l2if->l2_wq.bfd.fd;
-	}
-
-	local.sun_family = AF_UNIX;
-	strncpy(local.sun_path, socket_path, sizeof(local.sun_path));
-	local.sun_path[sizeof(local.sun_path) - 1] = '\0';
-
-	rc = connect(l1l2if->l2_wq.bfd.fd, (struct sockaddr *) &local,
-		     sizeof(local));
-	if (rc < 0) {
-		fprintf(stderr, "Failed to connect to '%s': %s\n", local.sun_path,
-			strerror(errno));
-		fprintf(stderr, "Please run osmocon for this socket.\n");
-		close(l1l2if->l2_wq.bfd.fd);
-		return rc;
-	}
-
-	osmo_wqueue_init(&l1l2if->l2_wq, 100);
-	l1l2if->l2_wq.bfd.data = l1l2if;
-	l1l2if->l2_wq.bfd.when = BSC_FD_READ;
-	l1l2if->l2_wq.read_cb = layer2_read;
-	l1l2if->l2_wq.write_cb = layer2_write;
-
-	rc = osmo_fd_register(&l1l2if->l2_wq.bfd);
-	if (rc != 0) {
-		fprintf(stderr, "Failed to register fd.\n");
-		close(l1l2if->l2_wq.bfd.fd);
-		return rc;
-	}
-
-	return 0;
-}
-
-static int layer2_close(struct osmo_l1l2_if *l1l2if)
-{
-	if (l1l2if->l2_wq.bfd.fd <= 0)
-		return -EINVAL;
-
-	close(l1l2if->l2_wq.bfd.fd);
-	l1l2if->l2_wq.bfd.fd = -1;
-	osmo_fd_unregister(&l1l2if->l2_wq.bfd);
-
-	return 0;
-}
-
-static int osmo_send_l1(struct osmo_l1l2_if *l1l2if, struct msgb *msg)
+static struct msgb *osmo_l1if_alloc(uint8_t msg_type)
 {
-	uint16_t *len;
-
-	DEBUGP(DL1C, "Sending: '%s'\n", osmo_hexdump(msg->data, msg->len));
-
-	if (msg->l1h != msg->data)
-		LOGP(DL1C, LOGL_ERROR, "Message L1 header != Message Data\n");
-	
-	/* prepend 16bit length before sending */
-	len = (uint16_t *) msgb_push(msg, sizeof(*len));
-	*len = htons(msg->len - sizeof(*len));
-
-	if (osmo_wqueue_enqueue(&l1l2if->l2_wq, msg) != 0) {
-		LOGP(DL1C, LOGL_ERROR, "Failed to enqueue msg.\n");
-		msgb_free(msg);
-		return -1;
-	}
-
-	return 0;
-}
-
-/*
- * messages to and from layer 1
- */
-
-static struct msgb *osmo_l1_alloc(uint8_t msg_type)
-{
-	struct l1ctl_hdr *l1h;
-	struct msgb *msg = msgb_alloc_headroom(256, 4, "osmo_l1");
+	struct l1if_hdr *l1h;
+	struct msgb *msg = msgb_alloc_headroom(256, 16, "osmo_l1if");
 
 	if (!msg) {
 		LOGP(DL1C, LOGL_ERROR, "Failed to allocate memory.\n");
@@ -215,12 +62,11 @@ static struct msgb *osmo_l1_alloc(uint8_t msg_type)
 	}
 
 	msg->l1h = msgb_put(msg, sizeof(*l1h));
-	l1h = (struct l1ctl_hdr *) msg->l1h;
+	l1h = (struct l1if_hdr *) msg->l1h;
 	l1h->msg_type = msg_type;
 	
 	return msg;
 }
-
 /* l1 confirms setup */
 static int l1if_setup_conf(struct gsm_bts_trx *trx)
 {
@@ -246,7 +92,6 @@ int l1if_setup(struct gsm_bts_trx *trx)
 	LOGP(DL1C, LOGL_INFO, "Setup TRX: arfcn=%d bsic=%d/%d\n",
 		arfcn, bsic / 8, bsic & 7);
 	
-// Sylvain: put your code here: init trx, then call on a confirm:
 	l1if_setup_conf(trx);
 
 	return 0;
@@ -259,7 +104,6 @@ static int l1if_new_si(struct gsm_bts_trx *trx, enum osmo_sysinfo_type osmo_si)
 	switch (osmo_si) {
 	case SYSINFO_TYPE_1:
 		name = "1";
-// Sylvain: put your code here
 		break;
 	case SYSINFO_TYPE_2:
 		name = "2";
@@ -309,8 +153,6 @@ static int l1if_new_si(struct gsm_bts_trx *trx, enum osmo_sysinfo_type osmo_si)
 
 	LOGP(DL1C, LOGL_INFO, "Providing Sysinfo %s to L1\n",
 		name);
-// FIXME: prepare bursts and send
-// Sylvain: put your code here
 
 	return 0;
 }
@@ -327,20 +169,22 @@ static int l1if_signal_cbfn(unsigned int subsys, unsigned int signal, void *hdlr
 	return 0;
 }
 
-static int l1if_reset_cnf(struct bbl1_hdl *bbl1h, struct msgb *msg, enum baseband_role bb_role)
+static int l1if_reset_cnf(struct osmo_l1ctl *l1ctl, struct msgb *msg)
 {
-	struct gsm_bts_trx *trx = bbl1h->trx;
+	enum baseband_role bb_role = l1ctl->bb_role;
+	struct osmo_l1_if *l1if = l1ctl->l1_if;
+	struct gsm_bts_trx *trx = l1if->trx;
 	int on = 1; // FIXME: handle failure (wrong firmware)
 
 	if (bb_role == BASEBAND_TX) {
 		LOGP(DL1C, LOGL_INFO, "Reset of TX baseband complete\n");
-		bbl1h->reset_cnf_tx = 1;
+		l1if->reset_cnf_tx = 1;
 	}
 	if (bb_role == BASEBAND_RX) {
 		LOGP(DL1C, LOGL_INFO, "Reset of RX baseband complete\n");
-		bbl1h->reset_cnf_rx = 1;
+		l1if->reset_cnf_rx = 1;
 	}
-	if (!bbl1h->reset_cnf_tx || (!bbl1h->reset_cnf_rx && !tx_only)) {
+	if (!l1if->reset_cnf_tx || (!l1if->reset_cnf_rx && !tx_only)) {
 		LOGP(DL1C, LOGL_INFO, "Waiting for other baseband\n");
 		return 0;
 	}
@@ -365,12 +209,12 @@ static int l1if_reset_cnf(struct bbl1_hdl *bbl1h, struct msgb *msg, enum baseban
 
 int l1if_reset(struct gsm_bts_trx *trx)
 {
-	struct bbl1_hdl *bbl1h = trx_bbl1_hdl(trx);
+	struct osmo_l1_if *l1if = trx_l1_if(trx);
 	struct msgb *msg;
 	struct l1ctl_reset *res;
 	uint8_t type = L1CTL_RES_T_FULL;
 
-	msg = osmo_l1_alloc(L1CTL_RESET_REQ);
+	msg = osmo_l1if_alloc(L1IF_RESET_REQ);
 	if (!msg)
 		return -1;
 
@@ -378,12 +222,12 @@ int l1if_reset(struct gsm_bts_trx *trx)
 	res = (struct l1ctl_reset *) msgb_put(msg, sizeof(*res));
 	res->type = type;
 
-	osmo_send_l1(&bbl1h->l1l2if_tx, msg);
+	l1ctl_send(&l1if->l1ctl_tx, msg);
 
 	if (tx_only)
 		return 0;
 
-	msg = osmo_l1_alloc(L1CTL_RESET_REQ);
+	msg = osmo_l1if_alloc(L1IF_RESET_REQ);
 	if (!msg)
 		return -1;
 
@@ -391,17 +235,16 @@ int l1if_reset(struct gsm_bts_trx *trx)
 	res = (struct l1ctl_reset *) msgb_put(msg, sizeof(*res));
 	res->type = type;
 
-	osmo_send_l1(&bbl1h->l1l2if_rx, msg);
+	l1ctl_send(&l1if->l1ctl_rx, msg);
 
 	return 0;
 }
 
 /* Receive incoming data from L1 using L1CTL format */
-static int l1if_recv(struct osmo_l1l2_if *l1l2if, struct msgb *msg)
+int l1if_recv(struct osmo_l1ctl *l1ctl, struct msgb *msg)
 {
-	struct bbl1_hdl *bbl1h = l1l2if->bbl1h;
-	int rc = 0;
-	struct l1ctl_hdr *l1h;
+	int rc = -EINVAL;
+	struct l1if_hdr *l1h;
 	struct l1ctl_info_dl *dl;
 
 	if (msgb_l2len(msg) < sizeof(*dl)) {
@@ -411,60 +254,15 @@ static int l1if_recv(struct osmo_l1l2_if *l1l2if, struct msgb *msg)
 		return -1;
 	}
 
-	l1h = (struct l1ctl_hdr *) msg->l1h;
-
-	/* move the l1 header pointer to point _BEHIND_ l1ctl_hdr,
-	   as the l1ctl header is of no interest to subsequent code */
+	l1h = (struct l1if_hdr *) msg->l1h;
 	msg->l1h = l1h->data;
 
 	switch (l1h->msg_type) {
-	case L1CTL_RESET_IND:
-	case L1CTL_RESET_CONF:
-		rc = l1if_reset_cnf(bbl1h, msg, l1l2if->bb_role);
-		msgb_free(msg);
-		break;
-#if 0
-	case L1CTL_FBSB_CONF:
-		rc = rx_l1_fbsb_conf(ms, msg);
-		msgb_free(msg);
-		break;
-	case L1CTL_DATA_IND:
-		rc = rx_ph_data_ind(ms, msg);
-		break;
-	case L1CTL_DATA_CONF:
-		rc = rx_ph_data_conf(ms, msg);
-		break;
-	case L1CTL_PM_CONF:
-		rc = rx_l1_pm_conf(ms, msg);
-		if (l1h->flags & L1CTL_F_DONE)
-			osmo_signal_dispatch(SS_L1CTL, S_L1CTL_PM_DONE, ms);
+	case L1IF_RESET_IND:
+	case L1IF_RESET_CNF:
+		rc = l1if_reset_cnf(l1ctl, msg);
 		msgb_free(msg);
 		break;
-	case L1CTL_RACH_CONF:
-		rc = rx_l1_rach_conf(ms, msg);
-		break;
-	case L1CTL_CCCH_MODE_CONF:
-		rc = rx_l1_ccch_mode_conf(ms, msg);
-		msgb_free(msg);
-		break;
-	case L1CTL_TCH_MODE_CONF:
-		rc = rx_l1_tch_mode_conf(ms, msg);
-		msgb_free(msg);
-		break;
-	case L1CTL_SIM_CONF:
-		rc = rx_l1_sim_conf(ms, msg);
-		break;
-	case L1CTL_NEIGH_PM_IND:
-		rc = rx_l1_neigh_pm_ind(ms, msg);
-		msgb_free(msg);
-		break;
-	case L1CTL_TRAFFIC_IND:
-		rc = rx_l1_traffic_ind(ms, msg);
-		break;
-	case L1CTL_TRAFFIC_CONF:
-		msgb_free(msg);
-		break;
-#endif
 	default:
 		LOGP(DL1C, LOGL_ERROR, "Unknown MSG: %u\n", l1h->msg_type);
 		msgb_free(msg);
@@ -476,38 +274,38 @@ static int l1if_recv(struct osmo_l1l2_if *l1l2if, struct msgb *msg)
 
 int l1if_open(struct gsm_bts_trx *trx, const char *socket_path)
 {
-	struct bbl1_hdl *bbl1h;
+	struct osmo_l1_if *l1if;
 	char pathname[128];
 	int rc;
 
 	osmo_signal_register_handler(SS_GLOBAL, l1if_signal_cbfn, NULL);
 
-	bbl1h = talloc_zero(tall_bts_ctx, struct bbl1_hdl);
-	if (!bbl1h)
+	l1if = talloc_zero(tall_bts_ctx, struct osmo_l1_if);
+	if (!l1if)
 		return -ENOMEM;
-	bbl1h->trx = trx;
-	bbl1h->l1l2if_tx.bb_role = BASEBAND_TX;
-	bbl1h->l1l2if_tx.bbl1h = bbl1h;
+	l1if->trx = trx;
+	l1if->l1ctl_tx.bb_role = BASEBAND_TX;
+	l1if->l1ctl_tx.l1_if = l1if;
 	sprintf(pathname, "%s.tx", socket_path);
 	LOGP(DL1C, LOGL_INFO, "Open connection to TX baseband.\n");
-	rc = layer2_open(&bbl1h->l1l2if_tx, pathname);
+	rc = l1socket_open(&l1if->l1ctl_tx, pathname);
 	if (rc) {
-		talloc_free(bbl1h);
+		talloc_free(l1if);
 		return rc;
 	}
 	if (!tx_only) {
-		bbl1h->l1l2if_rx.bb_role = BASEBAND_RX;
-		bbl1h->l1l2if_rx.bbl1h = bbl1h;
+		l1if->l1ctl_rx.bb_role = BASEBAND_RX;
+		l1if->l1ctl_rx.l1_if = l1if;
 		sprintf(pathname, "%s.rx", socket_path);
 		LOGP(DL1C, LOGL_INFO, "Open connection to RX baseband.\n");
-		rc = layer2_open(&bbl1h->l1l2if_rx, pathname);
+		rc = l1socket_open(&l1if->l1ctl_rx, pathname);
 		if (rc) {
-			layer2_close(&bbl1h->l1l2if_tx);
-			talloc_free(bbl1h);
+			l1socket_close(&l1if->l1ctl_tx);
+			talloc_free(l1if);
 			return rc;
 		}
 	}
-	trx->role_bts.l1h = bbl1h;
+	trx->role_bts.l1h = l1if;
 	trx->nominal_power = 23;
 
 	return 0;
@@ -515,11 +313,12 @@ int l1if_open(struct gsm_bts_trx *trx, const char *socket_path)
 
 int l1if_close(struct gsm_bts_trx *trx)
 {
-	struct bbl1_hdl *bbl1h = trx_bbl1_hdl(trx);
+	struct osmo_l1_if *l1if = trx_l1_if(trx);
 
-	layer2_close(&bbl1h->l1l2if_tx);
-	layer2_close(&bbl1h->l1l2if_rx);
-	talloc_free(bbl1h);
+	l1socket_close(&l1if->l1ctl_tx);
+	l1socket_close(&l1if->l1ctl_rx);
+	talloc_free(l1if);
 	osmo_signal_unregister_handler(SS_GLOBAL, l1if_signal_cbfn, NULL);
 	return 0;
 }
+
diff --git a/src/osmo-bts-bb/l1_if.h b/src/osmo-bts-bb/l1_if.h
index ce97ba42..bdd33bcc 100644
--- a/src/osmo-bts-bb/l1_if.h
+++ b/src/osmo-bts-bb/l1_if.h
@@ -1,30 +1,31 @@
-#ifndef _BB_L1_H
-#define _BB_L1_H
-
-extern uint16_t ref_arfcn;
-
-#include <osmocom/core/write_queue.h>
-
-enum baseband_role {
-	BASEBAND_TX,
-	BASEBAND_RX,
+#ifndef _BB_L1_IF_H
+#define _BB_L1_IF_H
+
+enum l1if_prim {
+	L1IF_RESET_REQ,
+	L1IF_RESET_IND,
+	L1IF_RESET_CNF,
+	L1IF_SETUP_REQ,
+	L1IF_SETUP_CNF,
+	L1IF_BCCH_REQ,
+	L1IF_RACH_IND,
 };
 
-struct osmo_l1l2_if {
-
-	enum baseband_role bb_role;
-	struct bbl1_hdl *bbl1h;
-	struct osmo_wqueue l2_wq;
-};
+struct l1if_hdr {
+	uint8_t msg_type;
+	uint8_t data[0];
+} __attribute__((packed));
 
-struct bbl1_hdl {
+struct osmo_l1_if {
 	struct gsm_bts_trx *trx;
-	struct osmo_l1l2_if l1l2if_tx, l1l2if_rx;
+	struct osmo_l1ctl l1ctl_tx, l1ctl_rx;
 	int reset_cnf_tx, reset_cnf_rx;
 };
 
 int l1if_setup(struct gsm_bts_trx *trx);
+int l1if_reset(struct gsm_bts_trx *trx);
+int l1if_recv(struct osmo_l1ctl *l1ctl, struct msgb *msg);
 int l1if_open(struct gsm_bts_trx *trx,  const char *socket_path);
 int l1if_close(struct gsm_bts_trx *trx);
 
-#endif /* _BB_L1_H */
+#endif /* _BB_L1_IF_H */
diff --git a/src/osmo-bts-bb/l1ctl.c b/src/osmo-bts-bb/l1ctl.c
new file mode 100644
index 00000000..e180fdd8
--- /dev/null
+++ b/src/osmo-bts-bb/l1ctl.c
@@ -0,0 +1,305 @@
+/* Interface to layer 1 of baseband */
+
+/* (C) 2010 by Holger Hans Peter Freyther
+ * (C) 2010 by Harald Welte <laforge@gnumonks.org>
+ * (C) 2011 by Andreas Eversberg <jolly@eversberg.eu>
+ *
+ * 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 <arpa/inet.h>
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+
+#include <osmocom/core/talloc.h>
+#include <osmocom/core/utils.h>
+//#include <osmocom/core/select.h>
+//#include <osmocom/core/timer.h>
+#include <osmocom/core/write_queue.h>
+#include <osmocom/gsm/gsm_utils.h>
+#include <osmocom/gsm/lapdm.h>
+
+#include <osmo-bts/logging.h>
+//#include <osmo-bts/bts.h>
+//#include <osmo-bts/oml.h>
+//#include <osmo-bts/gsm_data.h>
+//#include <osmo-bts/signal.h>
+
+#include "l1ctl.h"
+#include "l1_if.h"
+
+/*
+ * socket communication with baseband
+ */
+
+#define GSM_L2_LENGTH 256
+#define GSM_L2_HEADROOM 32
+
+static int l1ctl_recv(struct osmo_l1ctl *l1ctl, struct msgb *msg);
+
+static int l1socket_read(struct osmo_fd *fd)
+{
+	struct msgb *msg;
+	u_int16_t len;
+	int rc;
+
+	msg = msgb_alloc_headroom(GSM_L2_LENGTH+GSM_L2_HEADROOM, GSM_L2_HEADROOM, "Layer2");
+	if (!msg) {
+		LOGP(DL1C, LOGL_ERROR, "Failed to allocate msg.\n");
+		return -ENOMEM;
+	}
+
+	rc = read(fd->fd, &len, sizeof(len));
+	if (rc < sizeof(len)) {
+		fprintf(stderr, "Layer2 socket failed\n");
+		msgb_free(msg);
+		if (rc >= 0)
+			rc = -EIO;
+		l1socket_close((struct osmo_l1ctl *) fd->data);
+		return rc;
+	}
+
+	len = ntohs(len);
+	if (len > GSM_L2_LENGTH) {
+		LOGP(DL1C, LOGL_ERROR, "Length is too big: %u\n", len);
+		msgb_free(msg);
+		return -EINVAL;
+	}
+
+
+	msg->l1h = msgb_put(msg, len);
+	rc = read(fd->fd, msg->l1h, msgb_l1len(msg));
+	if (rc != msgb_l1len(msg)) {
+		LOGP(DL1C, LOGL_ERROR, "Can not read data: len=%d rc=%d "
+		     "errno=%d\n", len, rc, errno);
+		msgb_free(msg);
+		return rc;
+	}
+
+	l1ctl_recv((struct osmo_l1ctl *) fd->data, msg);
+
+	return 0;
+}
+
+static int l1socket_write(struct osmo_fd *fd, struct msgb *msg)
+{
+	int rc;
+
+	if (fd->fd <= 0)
+		return -EINVAL;
+
+	rc = write(fd->fd, msg->data, msg->len);
+	if (rc != msg->len) {
+		LOGP(DL1C, LOGL_ERROR, "Failed to write data: rc: %d\n", rc);
+		return rc;
+	}
+
+	return 0;
+}
+
+int l1socket_open(struct osmo_l1ctl *l1ctl, const char *socket_path)
+{
+	int rc;
+	struct sockaddr_un local;
+
+	l1ctl->l2_wq.bfd.fd = socket(AF_UNIX, SOCK_STREAM, 0);
+	if (l1ctl->l2_wq.bfd.fd < 0) {
+		fprintf(stderr, "Failed to create unix domain socket.\n");
+		return l1ctl->l2_wq.bfd.fd;
+	}
+
+	local.sun_family = AF_UNIX;
+	strncpy(local.sun_path, socket_path, sizeof(local.sun_path));
+	local.sun_path[sizeof(local.sun_path) - 1] = '\0';
+
+	rc = connect(l1ctl->l2_wq.bfd.fd, (struct sockaddr *) &local,
+		     sizeof(local));
+	if (rc < 0) {
+		fprintf(stderr, "Failed to connect to '%s': %s\n", local.sun_path,
+			strerror(errno));
+		fprintf(stderr, "Please run osmocon for this socket.\n");
+		close(l1ctl->l2_wq.bfd.fd);
+		return rc;
+	}
+
+	osmo_wqueue_init(&l1ctl->l2_wq, 100);
+	l1ctl->l2_wq.bfd.data = l1ctl;
+	l1ctl->l2_wq.bfd.when = BSC_FD_READ;
+	l1ctl->l2_wq.read_cb = l1socket_read;
+	l1ctl->l2_wq.write_cb = l1socket_write;
+
+	rc = osmo_fd_register(&l1ctl->l2_wq.bfd);
+	if (rc != 0) {
+		fprintf(stderr, "Failed to register fd.\n");
+		close(l1ctl->l2_wq.bfd.fd);
+		return rc;
+	}
+
+	return 0;
+}
+
+int l1socket_close(struct osmo_l1ctl *l1ctl)
+{
+	if (l1ctl->l2_wq.bfd.fd <= 0)
+		return -EINVAL;
+
+	close(l1ctl->l2_wq.bfd.fd);
+	l1ctl->l2_wq.bfd.fd = -1;
+	osmo_fd_unregister(&l1ctl->l2_wq.bfd);
+
+	return 0;
+}
+
+static int osmo_send_l1(struct osmo_l1ctl *l1ctl, struct msgb *msg)
+{
+	uint16_t *len;
+
+	DEBUGP(DL1C, "Sending: '%s'\n", osmo_hexdump(msg->data, msg->len));
+
+	if (msg->l1h != msg->data)
+		LOGP(DL1C, LOGL_ERROR, "Message L1 header != Message Data\n");
+	
+	/* prepend 16bit length before sending */
+	len = (uint16_t *) msgb_push(msg, sizeof(*len));
+	*len = htons(msg->len - sizeof(*len));
+
+	if (osmo_wqueue_enqueue(&l1ctl->l2_wq, msg) != 0) {
+		LOGP(DL1C, LOGL_ERROR, "Failed to enqueue msg.\n");
+		msgb_free(msg);
+		return -1;
+	}
+
+	return 0;
+}
+
+/*
+ * messages to and from layer 1
+ */
+
+static struct msgb *osmo_l1ctl_alloc(uint8_t msg_type)
+{
+	struct l1ctl_hdr *l1h;
+	struct msgb *msg = msgb_alloc_headroom(256, 4, "osmo_l1ctl");
+
+	if (!msg) {
+		LOGP(DL1C, LOGL_ERROR, "Failed to allocate memory.\n");
+		return NULL;
+	}
+
+	msg->l1h = msgb_put(msg, sizeof(*l1h));
+	l1h = (struct l1ctl_hdr *) msg->l1h;
+	l1h->msg_type = msg_type;
+	
+	return msg;
+}
+
+static int l1ctl_reset_req(struct osmo_l1ctl *l1ctl, struct msgb *msg, uint8_t msg_type)
+{
+	struct l1ctl_hdr *l1h;
+
+	l1h = (struct l1ctl_hdr *) msgb_push(msg, sizeof(*l1h));
+	msg->l1h = (uint8_t *) l1h;
+	l1h->msg_type = L1CTL_RESET_REQ;
+
+	osmo_send_l1(l1ctl, msg);
+
+	return 0;
+}
+
+/* got data from upper L1 interface */
+int l1ctl_send(struct osmo_l1ctl *l1ctl, struct msgb *msg)
+{
+	int rc = 0;
+	struct l1if_hdr *l1h;
+	uint8_t msg_type;
+
+	l1h = (struct l1if_hdr *) msg->l1h;
+
+	msg_type = l1h->msg_type;
+	msg->l1h = NULL;
+	msgb_pull(msg, sizeof(*l1h));
+
+	switch (msg_type) {
+	case L1IF_RESET_REQ:
+		rc = l1ctl_reset_req(l1ctl, msg, msg_type);
+		break;
+	default:
+		LOGP(DL1C, LOGL_ERROR, "Unknown MSG: %u\n", l1h->msg_type);
+		msgb_free(msg);
+		break;
+	}
+
+	return rc;
+}
+static int l1ctl_reset_ind(struct osmo_l1ctl *l1ctl, struct msgb *msg, uint8_t msg_type)
+{
+	struct l1if_hdr *l1h;
+
+	if (msg_type == L1CTL_RESET_IND)
+		msg_type = L1IF_RESET_IND;
+	else
+		msg_type = L1IF_RESET_CNF;
+
+	l1h = (struct l1if_hdr *) msgb_push(msg, sizeof(*l1h));
+	msg->l1h = (uint8_t *) l1h;
+	l1h->msg_type = msg_type;
+
+	return l1if_recv(l1ctl, msg);
+}
+
+
+/* Receive incoming data from L1 using L1CTL format */
+static int l1ctl_recv(struct osmo_l1ctl *l1ctl, struct msgb *msg)
+{
+	int rc = 0;
+	struct l1ctl_hdr *l1h;
+	struct l1ctl_info_dl *dl;
+	uint8_t msg_type;
+
+	if (msgb_l2len(msg) < sizeof(*dl)) {
+		LOGP(DL1C, LOGL_ERROR, "Short Layer2 message: %u\n",
+			msgb_l2len(msg));
+		msgb_free(msg);
+		return -1;
+	}
+
+	l1h = (struct l1ctl_hdr *) msg->l1h;
+	msg_type = l1h->msg_type;
+	msg->l1h = NULL;
+	msgb_pull(msg, sizeof(*l1h));
+
+	switch (msg_type) {
+	case L1CTL_RESET_IND:
+	case L1CTL_RESET_CONF:
+		rc = l1ctl_reset_ind(l1ctl, msg, msg_type);
+		break;
+	default:
+		LOGP(DL1C, LOGL_ERROR, "Unknown MSG: %u\n", l1h->msg_type);
+		msgb_free(msg);
+		break;
+	}
+
+	return rc;
+}
diff --git a/src/osmo-bts-bb/l1ctl.h b/src/osmo-bts-bb/l1ctl.h
new file mode 100644
index 00000000..b1402fb0
--- /dev/null
+++ b/src/osmo-bts-bb/l1ctl.h
@@ -0,0 +1,109 @@
+#ifndef _BB_L1CTL_H
+#define _BB_L1CTL_H
+
+#include <osmocom/core/write_queue.h>
+
+enum baseband_role {
+	BASEBAND_TX,
+	BASEBAND_RX,
+};
+
+struct osmo_l1ctl {
+
+	enum baseband_role bb_role;
+	struct osmo_l1_if *l1_if;
+	struct osmo_wqueue l2_wq;
+};
+
+int l1ctl_send(struct osmo_l1ctl *l1ctl, struct msgb *msg);
+int l1socket_open(struct osmo_l1ctl *l1ctl, const char *socket_path);
+int l1socket_close(struct osmo_l1ctl *l1ctl);
+
+/*
+ * L1CTL interface
+ */
+
+enum {
+	_L1CTL_NONE		= 0,
+	L1CTL_FBSB_REQ,
+	L1CTL_FBSB_CONF,
+	L1CTL_DATA_IND,
+	L1CTL_RACH_REQ,
+	L1CTL_DM_EST_REQ,
+	L1CTL_DATA_REQ,
+	L1CTL_RESET_IND,
+	L1CTL_PM_REQ,		/* power measurement */
+	L1CTL_PM_CONF,		/* power measurement */
+	L1CTL_ECHO_REQ,
+	L1CTL_ECHO_CONF,
+	L1CTL_RACH_CONF,
+	L1CTL_RESET_REQ,
+	L1CTL_RESET_CONF,
+	L1CTL_DATA_CONF,
+	L1CTL_CCCH_MODE_REQ,
+	L1CTL_CCCH_MODE_CONF,
+	L1CTL_DM_REL_REQ,
+	L1CTL_PARAM_REQ,
+	L1CTL_DM_FREQ_REQ,
+	L1CTL_CRYPTO_REQ,
+	L1CTL_SIM_REQ,
+	L1CTL_SIM_CONF,
+	L1CTL_TCH_MODE_REQ,
+	L1CTL_TCH_MODE_CONF,
+	L1CTL_NEIGH_PM_REQ,
+	L1CTL_NEIGH_PM_IND,
+	L1CTL_TRAFFIC_REQ,
+	L1CTL_TRAFFIC_CONF,
+	L1CTL_TRAFFIC_IND,
+};
+/* there are no more messages in a sequence */
+#define L1CTL_F_DONE	0x01
+
+struct l1ctl_hdr {
+	uint8_t msg_type;
+	uint8_t flags;
+	uint8_t padding[2];
+	uint8_t data[0];
+} __attribute__((packed));
+
+struct l1ctl_info_dl {
+	/* GSM 08.58 channel number (9.3.1) */
+	uint8_t chan_nr;
+	/* GSM 08.58 link identifier (9.3.2) */
+	uint8_t link_id;
+	/* the ARFCN and the band. FIXME: what about MAIO? */
+	uint16_t band_arfcn;
+
+	uint32_t frame_nr;
+
+	uint8_t rx_level;	/* 0 .. 63 in typical GSM notation (dBm+110) */
+	uint8_t snr;		/* Signal/Noise Ration (dB) */
+	uint8_t num_biterr;
+	uint8_t fire_crc;
+
+	uint8_t payload[0];
+} __attribute__((packed));
+
+struct l1ctl_info_ul {
+	/* GSM 08.58 channel number (9.3.1) */
+	uint8_t chan_nr;
+	/* GSM 08.58 link identifier (9.3.2) */
+	uint8_t link_id;
+	uint8_t padding[2];
+
+	uint8_t payload[0];
+} __attribute__((packed));
+
+enum l1ctl_reset_type {
+	L1CTL_RES_T_BOOT,	/* only _IND */
+	L1CTL_RES_T_FULL,
+	L1CTL_RES_T_SCHED,
+};
+
+/* argument to L1CTL_RESET_REQ and L1CTL_RESET_IND */
+struct l1ctl_reset {
+	uint8_t type;
+	uint8_t pad[3];
+} __attribute__((packed));
+
+#endif /* _BB_L1CTL_H */
diff --git a/src/osmo-bts-bb/main.c b/src/osmo-bts-bb/main.c
index 1ae46255..2b755837 100644
--- a/src/osmo-bts-bb/main.c
+++ b/src/osmo-bts-bb/main.c
@@ -32,6 +32,7 @@
 #include <osmo-bts/bts.h>
 #include <osmo-bts/vty.h>
 
+#include "l1ctl.h"
 #include "l1_if.h"
 
 #include <net/if.h>
@@ -49,6 +50,7 @@
 char *debugs = "DL1C:DLLAPDM:DABIS:DOML:DRSL:DSUM";
 int debug_set = 0;
 int level_set = 0;
+uint16_t ref_arfcn = 0;
 int ref_set = 0;
 static char *layer2_socket_path = "/tmp/osmocom_l2";
 int tx_only = 0;
@@ -99,7 +101,7 @@ struct ipabis_link *link_init(struct gsm_bts *bts, uint32_t bsc_ip)
 	int rc;
 
 	link->bts = bts;
-	bts->oml_link = link;
+	bts->oml_link = (void *)link;
 
 	rc = abis_open(link, bsc_ip);
 	if (rc < 0)
diff --git a/src/osmo-bts-bb/oml.c b/src/osmo-bts-bb/oml.c
index 32f7e1c9..c812a3a7 100644
--- a/src/osmo-bts-bb/oml.c
+++ b/src/osmo-bts-bb/oml.c
@@ -27,6 +27,7 @@
 #include <osmo-bts/logging.h>
 #include <osmo-bts/oml.h>
 
+#include "l1ctl.h"
 #include "l1_if.h"
 
 int gsm_abis_mo_check_attr(const struct gsm_abis_mo *mo, uint8_t *attr_ids,