re-work original osmo-bts with support for sysmocom femtobts

This code re-works osmo-bts to add support for the upcoming sysmocom BTS.

It also tries to add some level of abstraction between the generic
part of a BTS (A-bis, RSL, OML, data structures, paging scheduling,
BCCH/AGCH scheduling, etc.) and the actual hardware-specific bits.

The hardware-specific bits are currently only implemented for the sysmocom
femtobts, but should be (re-)added for osmocom-bb, as well as a virtual
BTS for simulation purpose later.

The sysmocom bts specific parts require hardware-specific header files
which are (at least currently) not publicly distributed.

1 files changed, 143 insertions, 0 deletions

diff --git a/src/osmo-bts-sysmo/l1_transp_fwd.c b/src/osmo-bts-sysmo/l1_transp_fwd.c
new file mode 100644
index 00000000..3d33751b
--- /dev/null
+++ b/src/osmo-bts-sysmo/l1_transp_fwd.c
@@ -0,0 +1,143 @@
+/* Interface handler for Sysmocom L1 (forwarding) */
+
+/* (C) 2011 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 <sys/types.h>
+#include <sys/stat.h>
+#include <sys/socket.h>
+
+#include <netinet/in.h>
+#include <arpa/inet.h>
+
+#include <osmocom/core/talloc.h>
+#include <osmocom/core/utils.h>
+#include <osmocom/core/select.h>
+#include <osmocom/core/write_queue.h>
+#include <osmocom/core/msgb.h>
+#include <osmocom/core/socket.h>
+#include <osmocom/gsm/gsm_utils.h>
+
+#include <osmo-bts/logging.h>
+#include <osmo-bts/gsm_data.h>
+
+#include <sysmocom/femtobts/femtobts.h>
+#include <sysmocom/femtobts/gsml1prim.h>
+#include <sysmocom/femtobts/gsml1const.h>
+#include <sysmocom/femtobts/gsml1types.h>
+
+#include "femtobts.h"
+#include "l1_if.h"
+#include "l1_transp.h"
+#include "l1_fwd.h"
+
+#define BTS_HOST "192.168.100.151"
+
+static const uint16_t fwd_udp_ports[] = {
+	[MQ_SYS_WRITE]	= L1FWD_SYS_PORT,
+	[MQ_L1_WRITE]	= L1FWD_L1_PORT,
+};
+
+static int fwd_read_cb(struct osmo_fd *ofd)
+{
+	struct msgb *msg = msgb_alloc_headroom(2048, 127, "udp_rx");
+	struct femtol1_hdl *fl1h = ofd->data;
+	int rc;
+
+	if (!msg)
+		return -ENOMEM;
+
+	msg->l1h = msg->data;
+	rc = read(ofd->fd, msg->l1h, msgb_tailroom(msg));
+	if (rc < 0) {
+		LOGP(DL1C, LOGL_ERROR, "Short read from UDP\n");
+		msgb_free(msg);
+		return rc;
+	} else if (rc == 0) {
+		LOGP(DL1C, LOGL_ERROR, "Len=0 from UDP\n");
+		msgb_free(msg);
+		return rc;
+	}
+	msgb_put(msg, rc);
+
+	if (ofd->priv_nr == MQ_SYS_WRITE)
+		rc = l1if_handle_sysprim(fl1h, msg);
+	else
+		rc = l1if_handle_l1prim(fl1h, msg);
+
+	return rc;
+}
+
+static int prim_write_cb(struct osmo_fd *ofd, struct msgb *msg)
+{
+	/* write to the fd */
+	return write(ofd->fd, msg->head, msg->len);
+}
+
+int l1if_transport_open(struct femtol1_hdl *fl1h)
+{
+	int rc, i;
+
+	printf("sizeof(GsmL1_Prim_t) = %lu\n", sizeof(GsmL1_Prim_t));
+	printf("sizeof(FemtoBts_Prim_t) = %lu\n", sizeof(FemtoBts_Prim_t));
+
+	for (i = 0; i < ARRAY_SIZE(fl1h->write_q); i++) {
+		struct osmo_wqueue *wq = &fl1h->write_q[i];
+		struct osmo_fd *ofd = &wq->bfd;
+
+		osmo_wqueue_init(wq, 10);
+		wq->write_cb = prim_write_cb;
+		wq->read_cb = fwd_read_cb;
+
+		ofd->data = fl1h;
+		ofd->priv_nr = i;
+		ofd->when |= BSC_FD_READ;
+
+		rc = osmo_sock_init_ofd(ofd, AF_UNSPEC, SOCK_DGRAM, IPPROTO_UDP,
+					BTS_HOST, fwd_udp_ports[i],
+					OSMO_SOCK_F_CONNECT);
+		if (rc < 0) {
+			talloc_free(fl1h);
+			return rc;
+		}
+	}
+
+	return 0;
+}
+
+int l1if_transport_close(struct femtol1_hdl *fl1h)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(fl1h->write_q); i++) {
+		struct osmo_wqueue *wq = &fl1h->write_q[i];
+		struct osmo_fd *ofd = &wq->bfd;
+
+		osmo_wqueue_clear(wq);
+		osmo_fd_unregister(ofd);
+		close(ofd->fd);
+	}
+	
+	return 0;
+}