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, 192 insertions, 0 deletions

diff --git a/src/osmo-bts-sysmo/l1_transp_hw.c b/src/osmo-bts-sysmo/l1_transp_hw.c
new file mode 100644
index 00000000..d7e01e92
--- /dev/null
+++ b/src/osmo-bts-sysmo/l1_transp_hw.c
@@ -0,0 +1,192 @@
+/* Interface handler for Sysmocom L1 (real hardware) */
+
+/* (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 <osmocom/core/talloc.h>
+#include <osmocom/core/utils.h>
+#include <osmocom/core/select.h>
+#include <osmocom/core/write_queue.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"
+
+
+#define DEV_SYS_DSP2ARM_NAME	"/dev/msgq/femtobts_dsp2arm"
+#define DEV_SYS_ARM2DSP_NAME	"/dev/msgq/femtobts_arm2dsp"
+#define DEV_L1_DSP2ARM_NAME	"/dev/msgq/gsml1_dsp2arm"
+#define DEV_L1_ARM2DSP_NAME	"/dev/msgq/gsml1_arm2dsp"
+
+static const char *rd_devnames[] = {
+	[MQ_SYS_READ]	= DEV_SYS_DSP2ARM_NAME,
+	[MQ_L1_READ]	= DEV_L1_DSP2ARM_NAME,
+};
+
+static const char *wr_devnames[] = {
+	[MQ_SYS_WRITE]	= DEV_SYS_ARM2DSP_NAME,
+	[MQ_L1_WRITE]	= DEV_L1_ARM2DSP_NAME,
+};
+
+/* callback when there's something to read from the l1 msg_queue */
+static int l1if_fd_cb(struct osmo_fd *ofd, unsigned int what)
+{
+	//struct msgb *msg = l1p_msgb_alloc();
+	struct msgb *msg = msgb_alloc_headroom(2048, 128, "1l_fd");
+	struct femtol1_hdl *fl1h = ofd->data;
+	int rc;
+
+	msg->l1h = msg->data;
+	rc = read(ofd->fd, msg->l1h, sizeof(GsmL1_Prim_t));
+	if (rc < 0) {
+		if (rc != -1) 
+			LOGP(DL1C, LOGL_ERROR, "error reading from L1 msg_queue: %s\n",
+				strerror(errno));
+		msgb_free(msg);
+		return rc;
+	}
+	msgb_put(msg, rc);
+
+	if (ofd->priv_nr == MQ_L1_WRITE)
+		return l1if_handle_l1prim(fl1h, msg);
+	else
+		return l1if_handle_sysprim(fl1h, msg);
+};
+
+/* callback when we can write to one of the l1 msg_queue devices */
+static int l1fd_write_cb(struct osmo_fd *ofd, struct msgb *msg)
+{
+	int rc;
+
+	rc = write(ofd->fd, msg->l1h, msgb_l1len(msg));
+	if (rc < 0) {
+		LOGP(DL1C, LOGL_ERROR, "error writing to L1 msg_queue: %s\n",
+			strerror(errno));
+		return rc;
+	} else if (rc < msg->len) {
+		LOGP(DL1C, LOGL_ERROR, "short write to L1 msg_queue: "
+			"%u < %u\n", rc, msg->len);
+		return -EIO;
+	}
+
+	return 0;
+}
+
+int l1if_transport_open(struct femtol1_hdl *hdl)
+{
+	int rc, i;
+
+	/* Step 1: Open all msg_queue file descriptors */
+	for (i = 0; i < ARRAY_SIZE(hdl->read_ofd); i++) {
+		struct osmo_fd *ofd = &hdl->read_ofd[i];
+
+		rc = open(rd_devnames[i], O_RDONLY);
+		if (rc < 0) {
+			LOGP(DL1C, LOGL_FATAL, "unable to open msg_queue: %s\n",
+				strerror(errno));
+			goto out_free;
+		}
+		ofd->fd = rc;
+		ofd->priv_nr = i;
+		ofd->data = hdl;
+		ofd->cb = l1if_fd_cb;
+		ofd->when = BSC_FD_READ;
+		rc = osmo_fd_register(ofd);
+		if (rc < 0) {
+			close(ofd->fd);
+			ofd->fd = -1;
+			goto out_free;
+		}
+	}
+	for (i = 0; i < ARRAY_SIZE(hdl->write_q); i++) {
+		struct osmo_wqueue *wq = &hdl->write_q[i];
+		struct osmo_fd *ofd = &hdl->write_q[i].bfd;
+
+		rc = open(wr_devnames[i], O_WRONLY);
+		if (rc < 0) {
+			LOGP(DL1C, LOGL_FATAL, "unable to open msg_queue: %s\n",
+				strerror(errno));
+			goto out_read;
+		}
+
+		osmo_wqueue_init(wq, 10);
+		wq->write_cb = l1fd_write_cb;
+
+		ofd->fd = rc;
+		ofd->priv_nr = i;
+		ofd->data = hdl;
+		ofd->when = BSC_FD_WRITE;
+		rc = osmo_fd_register(ofd);
+		if (rc < 0) {
+			close(ofd->fd);
+			ofd->fd = -1;
+			goto out_read;
+		}
+
+	}
+	return 0;
+
+out_read:
+	for (i = 0; i < ARRAY_SIZE(hdl->read_ofd); i++) {
+		close(hdl->read_ofd[i].fd);
+		osmo_fd_unregister(&hdl->read_ofd[i]);
+	}
+out_free:
+	talloc_free(hdl);
+	return rc;
+}
+
+int l1if_transport_close(struct femtol1_hdl *hdl)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(hdl->read_ofd); i++) {
+		struct osmo_fd *ofd = &hdl->read_ofd[i];
+
+		osmo_fd_unregister(ofd);
+		close(ofd->fd);
+		ofd->fd = -1;
+	}
+
+	for (i = 0; i < ARRAY_SIZE(hdl->write_q); i++) {
+		struct osmo_fd *ofd = &hdl->write_q[i].bfd;
+
+		osmo_fd_unregister(ofd);
+		close(ofd->fd);
+		ofd->fd = -1;
+	}
+	return 0;
+}