rlcmac: Handle SI13 from L1CTL

Change-Id: Ifaddf0e6e5cad7ea25672804c83c254579874813
---
M include/osmocom/gprs/rlcmac/rlcmac_private.h
M src/rlcmac/rlcmac.c
M src/rlcmac/rlcmac_prim.c
3 files changed, 44 insertions(+), 2 deletions(-)

diff --git a/include/osmocom/gprs/rlcmac/rlcmac_private.h b/include/osmocom/gprs/rlcmac/rlcmac_private.h
index 80461da..e2d2494 100644
--- a/include/osmocom/gprs/rlcmac/rlcmac_private.h
+++ b/include/osmocom/gprs/rlcmac/rlcmac_private.h
@@ -7,10 +7,12 @@
 
 #include <osmocom/core/msgb.h>
 #include <osmocom/core/tdef.h>
+#include <osmocom/gsm/gsm48_rest_octets.h>
 
 #include <osmocom/gprs/rlcmac/rlcmac_prim.h>
 #include <osmocom/gprs/rlcmac/rlcmac.h>
 #include <osmocom/gprs/rlcmac/coding_scheme.h>
+#include <osmocom/gprs/rlcmac/csn1_defs.h>
 
 /* 3GPP TS 44.064 § 8.3 TLLI assignment procedures */
 #define GPRS_RLCMAC_TLLI_UNASSIGNED (0xffffffff)
@@ -73,6 +75,11 @@
 	struct {
 		struct gprs_rlcmac_pdch_ulc *ulc[8];
 	} sched;
+
+	/* Last SI13 received from BCCH: */
+	bool si13_available;
+	uint8_t si13[GSM_MACBLOCK_LEN];
+	SI13_RestOctets_t si13ro;
 };
 
 extern struct gprs_rlcmac_ctx *g_ctx;
@@ -82,6 +89,7 @@
 struct gprs_rlcmac_dl_tbf *gprs_rlcmac_find_dl_tbf_by_tfi(uint8_t dl_tfi);
 struct gprs_rlcmac_ul_tbf *gprs_rlcmac_find_ul_tbf_by_tfi(uint8_t ul_tfi);
 int gprs_rlcmac_handle_ccch_imm_ass(const struct gsm48_imm_ass *ia);
+int gprs_rlcmac_handle_bcch_si13(const struct gsm48_system_information_type_13 *si13);
 int gprs_rlcmac_handle_gprs_dl_block(const struct osmo_gprs_rlcmac_prim *rlcmac_prim,
 				     enum gprs_rlcmac_coding_scheme cs);
 
diff --git a/src/rlcmac/rlcmac.c b/src/rlcmac/rlcmac.c
index cff7c79..39e5c9e 100644
--- a/src/rlcmac/rlcmac.c
+++ b/src/rlcmac/rlcmac.c
@@ -299,6 +299,25 @@
 	return rc;
 }
 
+int gprs_rlcmac_handle_bcch_si13(const struct gsm48_system_information_type_13 *si13)
+{
+	int rc;
+
+	LOGRLCMAC(LOGL_DEBUG, "Rx SI13 from lower layers\n");
+	memcpy(g_ctx->si13, si13, GSM_MACBLOCK_LEN);
+
+	rc = osmo_gprs_rlcmac_decode_si13ro(&g_ctx->si13ro, si13->rest_octets,
+					    GSM_MACBLOCK_LEN - offsetof(struct gsm48_system_information_type_13, rest_octets));
+	if (rc < 0) {
+		LOGRLCMAC(LOGL_ERROR, "Error decoding SI13: %s\n",
+			  osmo_hexdump((uint8_t *)si13, GSM_MACBLOCK_LEN));
+		return rc;
+	}
+
+	g_ctx->si13_available = true;
+	return rc;
+}
+
 static int gprs_rlcmac_handle_pkt_ul_ack_nack(const struct osmo_gprs_rlcmac_prim *rlcmac_prim, const RlcMacDownlink_t *dl_block)
 {
 	const Packet_Uplink_Ack_Nack_t *ack = &dl_block->u.Packet_Uplink_Ack_Nack;
diff --git a/src/rlcmac/rlcmac_prim.c b/src/rlcmac/rlcmac_prim.c
index 1707578..dcf4424 100644
--- a/src/rlcmac/rlcmac_prim.c
+++ b/src/rlcmac/rlcmac_prim.c
@@ -495,10 +495,16 @@
 	/* TODO: check if it's IMM_ASS: */
 	int rc;
 
-	if (rlcmac_prim->l1ctl.ccch_data_ind.data[2] == GSM48_MT_RR_IMM_ASS)
+	switch (rlcmac_prim->l1ctl.ccch_data_ind.data[2]) {
+	case GSM48_MT_RR_IMM_ASS:
 		rc = gprs_rlcmac_handle_ccch_imm_ass((struct gsm48_imm_ass *)rlcmac_prim->l1ctl.ccch_data_ind.data);
-	else
+		break;
+	case GSM48_MT_RR_SYSINFO_13:
+		rc = gprs_rlcmac_handle_bcch_si13((struct gsm48_system_information_type_13 *)rlcmac_prim->l1ctl.ccch_data_ind.data);
+		break;
+	default:
 		rc = -ENOTSUP;
+	}
 	return rc;
 }
 

