WIP: Implement packet access procedure FSM

Change-Id: I1dcaa593c6805873ef38511d4d562515b52c1f92

src/host/layer23/include/osmocom/bb/common/Makefile.am

@@ -10,6 +10,7 @@ noinst_HEADERS = \
 	gps.h \
 	sysinfo.h \
 	osmocom_data.h \
+	pkt_acc_proc_fsm.h \
 	utils.h \
 	sap_proto.h \
 	sap_fsm.h \

src/host/layer23/include/osmocom/bb/common/pkt_acc_proc_fsm.h

@@ -0,0 +1,31 @@
+/* Packet Access Procedure FSM */
+#pragma once
+
+#include <osmocom/core/fsm.h>
+
+struct osmocom_ms;
+
+enum apn_fsm_states {
+	PKT_ACC_PROC_ST_IDLE,
+	PKT_ACC_PROC_ST_ACTIVE,
+};
+
+enum pkt_acc_proc_fsm_events {
+	APN_EV_GPRS_ALLOWED,	/* data: bool *allowed */
+	APN_EV_GMM_ATTACHED,
+	APN_EV_GMM_DETACHED,
+	APN_EV_RX_SM_ACT_PDP_CTX_REJ, /* data: enum gsm48_gsm_cause *cause */
+	APN_EV_RX_SM_ACT_PDP_CTX_ACC,
+	APN_EV_RX_SM_DEACT_PDP_CTX_ACC,
+};
+
+struct pkt_acc_proc_fsm_ctx {
+	struct osmo_fsm_inst *fi;
+	struct osmocom_ms *ms;
+	uint8_t chan_req;
+};
+
+int pkt_acc_proc_fsm_ctx_init(struct pkt_acc_proc_fsm_ctx *ctx, struct osmocom_ms *ms);
+void pkt_acc_proc_fsm_ctx_release(struct pkt_acc_proc_fsm_ctx *ctx);
+
+int pkt_acc_proc_start(struct pkt_acc_proc_fsm_ctx *ctx, uint8_t chan_req);

src/host/layer23/src/common/Makefile.am

@@ -24,6 +24,7 @@ liblayer23_a_SOURCES = \
 	logging.c \
 	ms.c \
 	networks.c \
+	pkt_acc_proc_fsm.c \
 	sap_fsm.c \
 	sap_proto.c \
 	sap_interface.c \

src/host/layer23/src/common/pkt_acc_proc_fsm.c

@@ -0,0 +1,49 @@
+/* Packet Access Procedure FSM
+ * (C) 2023 by sysmocom - s.f.m.c. GmbH <info@sysmocom.de>
+ * 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 Affero 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/lienses/>.
+ *
+ */
+
+#include <stdbool.h>
+
+/* gsm48_rr.c:
+ * gsm48_rr_est_req()
+ *	gsm48_rr_chan_req()
+ *		gsm48_rr_tx_rand_acc()
+ */
+
+
+int pkt_acc_proc_start(struct pkt_acc_proc_fsm_ctx *ctx, uint8_t chan_req)
+{
+	struct gsm322_cellsel *cs = &ms->cellsel;
+	struct gsm48_rrlayer *rr = &ms->rrlayer;
+
+	OSMO_ASSERT(rr->state == GSM48_RR_ST_IDLE);
+
+	if (!cs->sel_si.si1 || !cs->sel_si.si13)
+		return -EAGAIN;
+	if (!cs->sel_si.gprs.supported)
+		return -ENOTSUP;
+
+	rr->cr_ra = chan_req;
+	memset(&rr->cr_hist[0], 0x00, sizeof(rr->cr_hist));
+
+	LOGP(DRR, LOGL_NOTICE, "Sending CHANNEL REQUEST (0x%02x)\n", rr->cr_ra);
+	l1ctl_tx_rach_req(ms, RSL_CHAN_RACH, 0x00, rr->cr_ra, 0,
+			  cs->ccch_mode == CCCH_MODE_COMBINED);
+
+	rr->state = GSM48_RR_ST_CONN_PEND;
+}