1 files changed, 562 insertions, 0 deletions
diff --git a/src/sysmo_l1_if.cpp b/src/sysmo_l1_if.cpp
new file mode 100644
index 00000000..09a31495
--- /dev/null
+++ b/src/sysmo_l1_if.cpp
@@ -0,0 +1,562 @@
+/* sysmo_l1_if.cpp
+ *
+ * Copyright (C) 2012 Andreas Eversberg <jolly@eversberg.eu>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * 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 General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+ */
+
+#include <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <assert.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+extern "C" {
+#include <osmocom/core/talloc.h>
+#include <osmocom/core/select.h>
+#include <osmocom/core/msgb.h>
+}
+
+#include <gprs_rlcmac.h>
+#include <pcu_l1_if.h>
+#include <gprs_debug.h>
+#include "../../osmo-bts/include/osmo-bts/pcuif_proto.h"
+
+static int pcu_sock_send(struct msgb *msg);
+static void pcu_sock_timeout(void *_priv);
+
+struct pcu_l1if_bts pcu_l1if_bts;
+
+// Variable for storage current FN.
+int frame_number;
+
+int get_current_fn()
+{
+	return frame_number;
+}
+
+void set_current_fn(int fn)
+{
+	frame_number = fn;
+}
+
+/*
+ * PCU messages
+ */
+
+struct msgb *pcu_msgb_alloc(uint8_t msg_type, uint8_t bts_nr)
+{
+	struct msgb *msg;
+	struct gsm_pcu_if *pcu_prim;
+
+	msg = msgb_alloc(sizeof(struct gsm_pcu_if), "pcu_sock_tx");
+	if (!msg)
+		return NULL;
+	msgb_put(msg, sizeof(struct gsm_pcu_if));
+	pcu_prim = (struct gsm_pcu_if *) msg->data;
+	pcu_prim->msg_type = msg_type;
+	pcu_prim->bts_nr = bts_nr;
+
+	return msg;
+}
+
+static int pcu_tx_act_req(uint8_t trx, uint8_t ts, uint8_t activate)
+{
+	struct msgb *msg;
+	struct gsm_pcu_if *pcu_prim;
+	struct gsm_pcu_if_act_req *act_req;
+
+	LOGP(DL1IF, LOGL_INFO, "Sending %s request: trx=%d ts=%d\n",
+		(activate) ? "activate" : "deactivate", trx, ts);
+
+	msg = pcu_msgb_alloc(PCU_IF_MSG_ACT_REQ, 0);
+	if (!msg)
+		return -ENOMEM;
+	pcu_prim = (struct gsm_pcu_if *) msg->data;
+	act_req = &pcu_prim->u.act_req;
+	act_req->activate = activate;
+	act_req->trx_nr = trx;
+	act_req->ts_nr = ts;
+
+	return pcu_sock_send(msg);
+}
+
+static int pcu_tx_data_req(uint8_t trx, uint8_t ts, uint8_t sapi,
+	uint16_t arfcn, uint32_t fn, uint8_t block_nr, uint8_t *data,
+	uint8_t len)
+{
+	struct msgb *msg;
+	struct gsm_pcu_if *pcu_prim;
+	struct gsm_pcu_if_data *data_req;
+
+	LOGP(DL1IF, LOGL_DEBUG, "Sending data request: trx=%d ts=%d sapi=%d "
+		"arfcn=%d fn=%d block=%d data=%s\n", trx, ts, sapi, arfcn, fn,
+		block_nr, osmo_hexdump(data, len));
+
+	msg = pcu_msgb_alloc(PCU_IF_MSG_DATA_REQ, 0);
+	if (!msg)
+		return -ENOMEM;
+	pcu_prim = (struct gsm_pcu_if *) msg->data;
+	data_req = &pcu_prim->u.data_req;
+
+	data_req->sapi = sapi;
+	data_req->fn = fn;
+	data_req->arfcn = arfcn;
+	data_req->trx_nr = trx;
+	data_req->ts_nr = ts;
+	data_req->block_nr = block_nr;
+	memcpy(data_req->data, data, len);
+	data_req->len = len;
+
+	return pcu_sock_send(msg);
+}
+
+void pcu_l1if_tx_pdtch(msgb *msg, uint8_t trx, uint8_t ts, uint16_t arfcn,
+	uint32_t fn, uint8_t block_nr)
+{
+	pcu_tx_data_req(trx, ts, PCU_IF_SAPI_PDTCH, arfcn, fn, block_nr,
+		msg->data, msg->len);
+	msgb_free(msg);
+}
+
+void pcu_l1if_tx_ptcch(msgb *msg, uint8_t trx, uint8_t ts, uint16_t arfcn,
+	uint32_t fn, uint8_t block_nr)
+{
+	pcu_tx_data_req(trx, ts, PCU_IF_SAPI_PTCCH, arfcn, fn, block_nr,
+		msg->data, msg->len);
+	msgb_free(msg);
+}
+
+void pcu_l1if_tx_agch(bitvec * block, int len)
+{
+	uint8_t data[24]; /* prefix PLEN */
+	
+	/* FIXME: why does OpenBTS has no PLEN and no fill in message? */
+	bitvec_pack(block, data + 1);
+	data[0] = (len << 2) | 0x01;
+	pcu_tx_data_req(0, 0, PCU_IF_SAPI_AGCH, 0, 0, 0, data, 23);
+}
+
+static void pcu_l1if_tx_bcch(uint8_t *data, int len)
+{
+	pcu_tx_data_req(0, 0, PCU_IF_SAPI_BCCH, 0, 0, 0, data, len);
+}
+
+static int pcu_rx_data_ind(struct gsm_pcu_if_data *data_ind)
+{
+	int rc = 0;
+	bitvec *block;
+
+	LOGP(DL1IF, LOGL_DEBUG, "Data indication received: sapi=%d arfcn=%d "
+		"block=%d data=%s\n", data_ind->sapi,
+		data_ind->arfcn, data_ind->block_nr,
+		osmo_hexdump(data_ind->data, data_ind->len));
+
+	switch (data_ind->sapi) {
+	case PCU_IF_SAPI_PDTCH:
+		block = bitvec_alloc(data_ind->len);
+		if (!block) {
+			rc = -ENOMEM;
+			break;
+		}
+		bitvec_unpack(block, data_ind->data);
+		gprs_rlcmac_rcv_block(block);
+		bitvec_free(block);
+		break;
+	default:
+		LOGP(DL1IF, LOGL_ERROR, "Received PCU data indication with "
+			"unsupported sapi %d\n", data_ind->sapi);
+		rc = -EINVAL;
+	}
+
+	return rc;
+}
+
+static int pcu_rx_rts_req(struct gsm_pcu_if_rts_req *rts_req)
+{
+	int rc = 0;
+
+	LOGP(DL1IF, LOGL_DEBUG, "RTS request received: trx=%d ts=%d sapi=%d "
+		"arfcn=%d fn=%d block=%d\n", rts_req->trx_nr, rts_req->ts_nr,
+		rts_req->sapi, rts_req->arfcn, rts_req->fn, rts_req->block_nr);
+
+	switch (rts_req->sapi) {
+	case PCU_IF_SAPI_PDTCH:
+		gprs_rlcmac_rcv_rts_block(rts_req->trx_nr, rts_req->ts_nr,
+			rts_req->arfcn, rts_req->fn, rts_req->block_nr);
+		break;
+	case PCU_IF_SAPI_PTCCH:
+		/* FIXME */
+		{
+			struct msgb *msg = msgb_alloc(23, "l1_prim");
+			memset(msgb_put(msg, 23), 0x2b, 23);
+			pcu_l1if_tx_ptcch(msg, rts_req->trx_nr, rts_req->ts_nr,
+				rts_req->arfcn, rts_req->fn, rts_req->block_nr);
+		}
+		break;
+	default:
+		LOGP(DL1IF, LOGL_ERROR, "Received PCU RTS request with "
+			"unsupported sapi %d\n", rts_req->sapi);
+		rc = -EINVAL;
+	}
+
+	return rc;
+}
+
+static int pcu_rx_rach_ind(struct gsm_pcu_if_rach_ind *rach_ind)
+{
+	int rc = 0;
+
+	LOGP(DL1IF, LOGL_INFO, "RACH request received: sapi=%d "
+		"qta=%d, ra=%d, fn=%d\n", rach_ind->sapi, rach_ind->qta,
+		rach_ind->ra, rach_ind->fn);
+
+	switch (rach_ind->sapi) {
+	case PCU_IF_SAPI_RACH:
+		rc = gprs_rlcmac_rcv_rach(rach_ind->ra, rach_ind->fn,
+			rach_ind->qta);
+		break;
+	default:
+		LOGP(DL1IF, LOGL_ERROR, "Received PCU rach request with "
+			"unsupported sapi %d\n", rach_ind->sapi);
+		rc = -EINVAL;
+	}
+
+	return rc;
+}
+
+static int pcu_rx_info_ind(struct gsm_pcu_if_info_ind *info_ind)
+{
+	int rc = 0;
+	int trx, ts;
+//	uint8_t si13[23];
+
+	LOGP(DL1IF, LOGL_INFO, "Info indication received:\n");
+
+	if (!(info_ind->flags & PCU_IF_FLAG_ACTIVE)) {
+		LOGP(DL1IF, LOGL_NOTICE, "BTS not available\n");
+		return 0;
+	}
+	LOGP(DL1IF, LOGL_INFO, "BTS available\n");
+
+	for (trx = 0; trx < 8; trx++) {
+		pcu_l1if_bts.trx[trx].arfcn = info_ind->trx[trx].arfcn;
+		for (ts = 0; ts < 8; ts++) {
+			if ((info_ind->trx[trx].pdch_mask & (1 << ts))) {
+				/* FIXME: activate dynamically at RLCMAC */
+				if (!pcu_l1if_bts.trx[trx].ts[ts].enable)
+					pcu_tx_act_req(trx, ts, 1);
+				pcu_l1if_bts.trx[trx].ts[ts].enable = 1;
+				pcu_l1if_bts.trx[trx].ts[ts].tsc =
+					info_ind->trx[trx].tsc[ts];
+				LOGP(DL1IF, LOGL_INFO, "PDCH: trx=%d ts=%d\n",
+					trx, ts);
+			} else {
+				if (pcu_l1if_bts.trx[trx].ts[ts].enable)
+					pcu_tx_act_req(trx, ts, 0);
+				pcu_l1if_bts.trx[trx].ts[ts].enable = 0;
+			}
+		}
+	}
+
+#warning FIXME: RAC
+//	rc = generate_si13(si13, 0 /* rac */);
+//	printf("rc=%d\n", rc);
+//	pcu_l1if_tx_bcch(si13, 23);
+
+	return rc;
+}
+
+static int pcu_rx(uint8_t msg_type, struct gsm_pcu_if *pcu_prim)
+{
+	int rc = 0;
+
+	switch (msg_type) {
+	case PCU_IF_MSG_DATA_IND:
+		rc = pcu_rx_data_ind(&pcu_prim->u.data_ind);
+		break;
+	case PCU_IF_MSG_RTS_REQ:
+		rc = pcu_rx_rts_req(&pcu_prim->u.rts_req);
+		break;
+	case PCU_IF_MSG_RACH_IND:
+		rc = pcu_rx_rach_ind(&pcu_prim->u.rach_ind);
+		break;
+	case PCU_IF_MSG_INFO_IND:
+		rc = pcu_rx_info_ind(&pcu_prim->u.info_ind);
+		break;
+	default:
+		LOGP(DL1IF, LOGL_ERROR, "Received unknwon PCU msg type %d\n",
+			msg_type);
+		rc = -EINVAL;
+	}
+
+	return rc;
+}
+
+/*
+ * SYSMO-PCU socket functions
+ */
+
+struct pcu_sock_state {
+	struct osmo_fd conn_bfd;	/* fd for connection to lcr */
+	struct osmo_timer_list timer;	/* socket connect retry timer */
+	struct llist_head upqueue;	/* queue for sending messages */
+} *pcu_sock_state = NULL;
+
+static int pcu_sock_send(struct msgb *msg)
+{
+	struct pcu_sock_state *state = pcu_sock_state;
+	struct osmo_fd *conn_bfd;
+
+	if (!state) {
+		LOGP(DL1IF, LOGL_NOTICE, "PCU socket not created, dropping "
+			"message\n");
+		return -EINVAL;
+	}
+	conn_bfd = &state->conn_bfd;
+	if (conn_bfd->fd <= 0) {
+		LOGP(DL1IF, LOGL_NOTICE, "PCU socket not connected, dropping "
+			"message\n");
+		return -EIO;
+	}
+	msgb_enqueue(&state->upqueue, msg);
+	conn_bfd->when |= BSC_FD_WRITE;
+
+	return 0;
+}
+
+static void pcu_sock_close(struct pcu_sock_state *state)
+{
+	struct osmo_fd *bfd = &state->conn_bfd;
+
+	LOGP(DL1IF, LOGL_NOTICE, "PCU socket has LOST connection\n");
+
+	close(bfd->fd);
+	bfd->fd = -1;
+	osmo_fd_unregister(bfd);
+
+	/* flush the queue */
+	while (!llist_empty(&state->upqueue)) {
+		struct msgb *msg = msgb_dequeue(&state->upqueue);
+		msgb_free(msg);
+	}
+
+	/* disable all slots */
+	memset(&pcu_l1if_bts, 0, sizeof(pcu_l1if_bts));
+
+	state->timer.cb = pcu_sock_timeout;
+	osmo_timer_schedule(&state->timer, 5, 0);
+}
+
+static int pcu_sock_read(struct osmo_fd *bfd)
+{
+	struct pcu_sock_state *state = (struct pcu_sock_state *)bfd->data;
+	struct gsm_pcu_if *pcu_prim;
+	struct msgb *msg;
+	int rc;
+
+	msg = msgb_alloc(sizeof(*pcu_prim), "pcu_sock_rx");
+	if (!msg)
+		return -ENOMEM;
+
+	pcu_prim = (struct gsm_pcu_if *) msg->tail;
+
+	rc = recv(bfd->fd, msg->tail, msgb_tailroom(msg), 0);
+	if (rc == 0)
+		goto close;
+
+	if (rc < 0) {
+		if (errno == EAGAIN)
+			return 0;
+		goto close;
+	}
+
+	rc = pcu_rx(pcu_prim->msg_type, pcu_prim);
+
+	/* as we always synchronously process the message in pcu_rx() and
+	 * its callbacks, we can free the message here. */
+	msgb_free(msg);
+
+	return rc;
+
+close:
+	msgb_free(msg);
+	pcu_sock_close(state);
+	return -1;
+}
+
+static int pcu_sock_write(struct osmo_fd *bfd)
+{
+	struct pcu_sock_state *state = (struct pcu_sock_state *)bfd->data;
+	int rc;
+
+	while (!llist_empty(&state->upqueue)) {
+		struct msgb *msg, *msg2;
+		struct gsm_pcu_if *pcu_prim;
+
+		/* peek at the beginning of the queue */
+		msg = llist_entry(state->upqueue.next, struct msgb, list);
+		pcu_prim = (struct gsm_pcu_if *)msg->data;
+
+		bfd->when &= ~BSC_FD_WRITE;
+
+		/* bug hunter 8-): maybe someone forgot msgb_put(...) ? */
+		if (!msgb_length(msg)) {
+			LOGP(DL1IF, LOGL_ERROR, "message type (%d) with ZERO "
+				"bytes!\n", pcu_prim->msg_type);
+			goto dontsend;
+		}
+
+		/* try to send it over the socket */
+		rc = write(bfd->fd, msgb_data(msg), msgb_length(msg));
+		if (rc == 0)
+			goto close;
+		if (rc < 0) {
+			if (errno == EAGAIN) {
+				bfd->when |= BSC_FD_WRITE;
+				break;
+			}
+			goto close;
+		}
+
+dontsend:
+		/* _after_ we send it, we can deueue */
+		msg2 = msgb_dequeue(&state->upqueue);
+		assert(msg == msg2);
+		msgb_free(msg);
+	}
+	return 0;
+
+close:
+	pcu_sock_close(state);
+
+	return -1;
+}
+
+static int pcu_sock_cb(struct osmo_fd *bfd, unsigned int flags)
+{
+	int rc = 0;
+
+	if (flags & BSC_FD_READ)
+		rc = pcu_sock_read(bfd);
+	if (rc < 0)
+		return rc;
+
+	if (flags & BSC_FD_WRITE)
+		rc = pcu_sock_write(bfd);
+
+	return rc;
+}
+
+int pcu_l1if_open(void)
+{
+	struct pcu_sock_state *state;
+	struct osmo_fd *bfd;
+	struct sockaddr_un local;
+	unsigned int namelen;
+	int rc;
+
+	memset(&pcu_l1if_bts, 0, sizeof(pcu_l1if_bts));
+
+	state = pcu_sock_state;
+	if (!state) {
+		state = talloc_zero(NULL, struct pcu_sock_state);
+		if (!state)
+			return -ENOMEM;
+		INIT_LLIST_HEAD(&state->upqueue);
+	}
+
+	bfd = &state->conn_bfd;
+
+	bfd->fd = socket(AF_UNIX, SOCK_SEQPACKET, 0);
+	if (bfd->fd < 0) {
+		LOGP(DL1IF, LOGL_ERROR, "Failed to create PCU-SYSMO socket.\n");
+		talloc_free(state);
+		return -1;
+	}
+
+	local.sun_family = AF_UNIX;
+	strncpy(local.sun_path, "/tmp/pcu_bts", sizeof(local.sun_path));
+	local.sun_path[sizeof(local.sun_path) - 1] = '\0';
+
+	/* we use the same magic that X11 uses in Xtranssock.c for
+	 * calculating the proper length of the sockaddr */
+#if defined(BSD44SOCKETS) || defined(__UNIXWARE__)
+	local.sun_len = strlen(local.sun_path);
+#endif
+#if defined(BSD44SOCKETS) || defined(SUN_LEN)
+	namelen = SUN_LEN(&local);
+#else
+	namelen = strlen(local.sun_path) +
+		  offsetof(struct sockaddr_un, sun_path);
+#endif
+	rc = connect(bfd->fd, (struct sockaddr *) &local, namelen);
+	if (rc != 0) {
+		LOGP(DL1IF, LOGL_ERROR, "Failed to Connect the PCU-SYSMO "
+			"socket, delaying... '%s'\n", local.sun_path);
+		close(bfd->fd);
+		bfd->fd = -1;
+		state->timer.cb = pcu_sock_timeout;
+		osmo_timer_schedule(&state->timer, 5, 0);
+		return -1;
+	}
+
+	bfd->when = BSC_FD_READ;
+	bfd->cb = pcu_sock_cb;
+	bfd->data = state;
+
+	rc = osmo_fd_register(bfd);
+	if (rc < 0) {
+		LOGP(DL1IF, LOGL_ERROR, "Could not register PCU fd: %d\n", rc);
+		close(bfd->fd);
+		talloc_free(state);
+		return rc;
+	}
+
+	LOGP(DL1IF, LOGL_NOTICE, "PCU-SYSMO socket has been connected\n");
+
+	pcu_sock_state = state;
+
+	return 0;
+}
+
+void pcu_l1if_close(void)
+{
+	struct pcu_sock_state *state = pcu_sock_state;
+	struct osmo_fd *bfd;
+
+	if (!state)
+		return;
+
+	if (osmo_timer_pending(&state->timer))
+		osmo_timer_del(&state->timer);
+
+	bfd = &state->conn_bfd;
+	if (bfd->fd > 0)
+		pcu_sock_close(state);
+	talloc_free(state);
+	pcu_sock_state = NULL;
+}
+
+static void pcu_sock_timeout(void *_priv)
+{
+	pcu_l1if_open();
+}
+
+
+
+