diff --git a/configure.in b/configure.ac
similarity index 97%
rename from configure.in
rename to configure.ac
index 2e22bb2..b923a21 100644
--- a/configure.in
+++ b/configure.ac
@@ -24,7 +24,7 @@
 saved_CFLAGS="$CFLAGS"
 CFLAGS="$CFLAGS -fvisibility=hidden "
 AC_MSG_CHECKING([if ${CC} supports -fvisibility=hidden])
-AC_COMPILE_IFELSE([char foo;],
+AC_COMPILE_IFELSE([AC_LANG_SOURCE([char foo;])],
       [ AC_MSG_RESULT([yes])
         SYMBOL_VISIBILITY="-fvisibility=hidden"],
         AC_MSG_RESULT([no]))
diff --git a/include/osmocom/gsm/Makefile.am b/include/osmocom/gsm/Makefile.am
index c3670ec..547933e 100644
--- a/include/osmocom/gsm/Makefile.am
+++ b/include/osmocom/gsm/Makefile.am
@@ -1,5 +1,6 @@
 osmogsm_HEADERS = a5.h comp128.h gsm0808.h gsm48_ie.h mncc.h rxlev_stat.h \
-		  gsm0480.h gsm48.h gsm_utils.h rsl.h tlv.h abis_nm.h
+		  gsm0480.h gsm48.h gsm_utils.h rsl.h tlv.h abis_nm.h \
+		  sysinfo.h
 
 SUBDIRS = protocol
 
diff --git a/include/osmocom/gsm/abis_nm.h b/include/osmocom/gsm/abis_nm.h
index 04e4575..dcc8d4b 100644
--- a/include/osmocom/gsm/abis_nm.h
+++ b/include/osmocom/gsm/abis_nm.h
@@ -9,16 +9,19 @@
 const enum abis_nm_msgtype abis_nm_sw_load_msgs[9];
 const enum abis_nm_msgtype abis_nm_nacks[33];
 
+extern const struct value_string abis_nm_obj_class_names[];
+extern const struct value_string abis_nm_adm_state_names[];
+
 const char *abis_nm_nack_cause_name(uint8_t cause);
 const char *abis_nm_nack_name(uint8_t nack);
 const char *abis_nm_event_type_name(uint8_t cause);
 const char *abis_nm_severity_name(uint8_t cause);
 const struct tlv_definition abis_nm_att_tlvdef;
-const char *abis_nm_obj_class_name(uint8_t oc);
 const char *abis_nm_opstate_name(uint8_t os);
 const char *abis_nm_avail_name(uint8_t avail);
 const char *abis_nm_test_name(uint8_t test);
-const char *abis_nm_adm_name(uint8_t adm);
 void abis_nm_debugp_foh(int ss, struct abis_om_fom_hdr *foh);
 
+int abis_nm_chcomb4pchan(enum gsm_phys_chan_config pchan);
+enum abis_nm_chan_comb abis_nm_pchan4chcomb(uint8_t chcomb);
 #endif /* _OSMO_GSM_ABIS_NM_H */
diff --git a/include/osmocom/gsm/gsm_utils.h b/include/osmocom/gsm/gsm_utils.h
index 19adb70..a0ef3c4 100644
--- a/include/osmocom/gsm/gsm_utils.h
+++ b/include/osmocom/gsm/gsm_utils.h
@@ -114,4 +114,30 @@
 
 uint32_t gprs_tmsi2tlli(uint32_t p_tmsi, enum gprs_tlli_type type);
 
+/* Osmocom internal, not part of any gsm spec */
+enum gsm_phys_chan_config {
+	GSM_PCHAN_NONE,
+	GSM_PCHAN_CCCH,
+	GSM_PCHAN_CCCH_SDCCH4,
+	GSM_PCHAN_TCH_F,
+	GSM_PCHAN_TCH_H,
+	GSM_PCHAN_SDCCH8_SACCH8C,
+	GSM_PCHAN_PDCH,		/* GPRS PDCH */
+	GSM_PCHAN_TCH_F_PDCH,	/* TCH/F if used, PDCH otherwise */
+	GSM_PCHAN_UNKNOWN,
+	_GSM_PCHAN_MAX
+};
+
+/* Osmocom internal, not part of any gsm spec */
+enum gsm_chan_t {
+	GSM_LCHAN_NONE,
+	GSM_LCHAN_SDCCH,
+	GSM_LCHAN_TCH_F,
+	GSM_LCHAN_TCH_H,
+	GSM_LCHAN_UNKNOWN,
+	GSM_LCHAN_CCCH,
+	_GSM_LCHAN_MAX
+};
+
+
 #endif
diff --git a/include/osmocom/gsm/protocol/gsm_04_08.h b/include/osmocom/gsm/protocol/gsm_04_08.h
index 3ad7dfd..39470e7 100644
--- a/include/osmocom/gsm/protocol/gsm_04_08.h
+++ b/include/osmocom/gsm/protocol/gsm_04_08.h
@@ -1257,6 +1257,9 @@
 	uint8_t rac;		/* Routing Area Code */
 } __attribute__ ((packed));
 
+#define GSM48_CELL_CHAN_DESC_SIZE	16
 
+#define GSM_MACBLOCK_LEN	23
+#define GSM_MACBLOCK_PADDING	0x2b
 
 #endif /* PROTO_GSM_04_08_H */
diff --git a/include/osmocom/gsm/sysinfo.h b/include/osmocom/gsm/sysinfo.h
new file mode 100644
index 0000000..a66f3f1
--- /dev/null
+++ b/include/osmocom/gsm/sysinfo.h
@@ -0,0 +1,40 @@
+#ifndef _OSMO_GSM_SYSINFO_H
+#define _OSMO_GSM_SYSINFO_H
+
+#include <osmocom/gsm/protocol/gsm_04_08.h>
+
+enum osmo_sysinfo_type {
+	SYSINFO_TYPE_NONE,
+	SYSINFO_TYPE_1,
+	SYSINFO_TYPE_2,
+	SYSINFO_TYPE_3,
+	SYSINFO_TYPE_4,
+	SYSINFO_TYPE_5,
+	SYSINFO_TYPE_6,
+	SYSINFO_TYPE_7,
+	SYSINFO_TYPE_8,
+	SYSINFO_TYPE_9,
+	SYSINFO_TYPE_10,
+	SYSINFO_TYPE_13,
+	SYSINFO_TYPE_16,
+	SYSINFO_TYPE_17,
+	SYSINFO_TYPE_18,
+	SYSINFO_TYPE_19,
+	SYSINFO_TYPE_20,
+	SYSINFO_TYPE_2bis,
+	SYSINFO_TYPE_2ter,
+	SYSINFO_TYPE_2quater,
+	SYSINFO_TYPE_5bis,
+	SYSINFO_TYPE_5ter,
+	/* FIXME all the various bis and ter */
+	_MAX_SYSINFO_TYPE
+};
+
+typedef uint8_t sysinfo_buf_t[GSM_MACBLOCK_LEN];
+
+extern const struct value_string osmo_sitype_strs[_MAX_SYSINFO_TYPE];
+
+uint8_t gsm_sitype2rsl(enum osmo_sysinfo_type si_type);
+enum osmo_sysinfo_type osmo_rsl2sitype(uint8_t rsl_si);
+
+#endif /* _OSMO_GSM_SYSINFO_H */
diff --git a/src/gsm/Makefile.am b/src/gsm/Makefile.am
index 94f137e..55b772f 100644
--- a/src/gsm/Makefile.am
+++ b/src/gsm/Makefile.am
@@ -8,7 +8,7 @@
 lib_LTLIBRARIES = libosmogsm.la
 
 libosmogsm_la_SOURCES = a5.c rxlev_stat.c tlv_parser.c comp128.c gsm_utils.c \
-                        rsl.c gsm48.c gsm48_ie.c gsm0808.c \
+                        rsl.c gsm48.c gsm48_ie.c gsm0808.c sysinfo.c \
 			gprs_cipher_core.c gsm0480.c abis_nm.c
 libosmogsm_la_LDFLAGS = -version-info $(LIBVERSION)
 libosmogsm_la_LIBADD = $(top_builddir)/src/libosmocore.la
diff --git a/src/gsm/abis_nm.c b/src/gsm/abis_nm.c
index acea4ed..a82194f 100644
--- a/src/gsm/abis_nm.c
+++ b/src/gsm/abis_nm.c
@@ -21,9 +21,12 @@
  */
 
 #include <stdint.h>
+#include <errno.h>
+
 #include <osmocom/core/utils.h>
 #include <osmocom/core/logging.h>
 #include <osmocom/gsm/tlv.h>
+#include <osmocom/gsm/gsm_utils.h>
 #include <osmocom/gsm/protocol/gsm_12_21.h>
 #include <osmocom/gsm/abis_nm.h>
 
@@ -308,7 +311,7 @@
 	},
 };
 
-static const struct value_string abis_nm_obj_class_names[] = {
+const struct value_string abis_nm_obj_class_names[] = {
 	{ NM_OC_SITE_MANAGER,	"SITE-MANAGER" },
 	{ NM_OC_BTS,		"BTS" },
 	{ NM_OC_RADIO_CARRIER,	"RADIO-CARRIER" },
@@ -329,11 +332,6 @@
 	{ 0,			NULL }
 };
 
-const char *abis_nm_obj_class_name(uint8_t oc)
-{
-	return get_value_string(abis_nm_obj_class_names, oc);
-}
-
 const char *abis_nm_opstate_name(uint8_t os)
 {
 	switch (os) {
@@ -384,7 +382,7 @@
 	return get_value_string(test_names, test);
 }
 
-static const struct value_string abis_nm_adm_state_names[] = {
+const struct value_string abis_nm_adm_state_names[] = {
 	{ NM_STATE_LOCKED,	"Locked" },
 	{ NM_STATE_UNLOCKED,	"Unlocked" },
 	{ NM_STATE_SHUTDOWN,	"Shutdown" },
@@ -392,15 +390,39 @@
 	{ 0, NULL }
 };
 
-const char *abis_nm_adm_name(uint8_t adm)
-{
-	return get_value_string(abis_nm_adm_state_names, adm);
-}
-
 void abis_nm_debugp_foh(int ss, struct abis_om_fom_hdr *foh)
 {
 	DEBUGP(ss, "OC=%s(%02x) INST=(%02x,%02x,%02x) ",
-		abis_nm_obj_class_name(foh->obj_class), foh->obj_class,
-		foh->obj_inst.bts_nr, foh->obj_inst.trx_nr,
+		get_value_string(abis_nm_obj_class_names, foh->obj_class),
+		foh->obj_class, foh->obj_inst.bts_nr, foh->obj_inst.trx_nr,
 		foh->obj_inst.ts_nr);
 }
+
+static const enum abis_nm_chan_comb chcomb4pchan[] = {
+	[GSM_PCHAN_CCCH]	= NM_CHANC_mainBCCH,
+	[GSM_PCHAN_CCCH_SDCCH4]	= NM_CHANC_BCCHComb,
+	[GSM_PCHAN_TCH_F]	= NM_CHANC_TCHFull,
+	[GSM_PCHAN_TCH_H]	= NM_CHANC_TCHHalf,
+	[GSM_PCHAN_SDCCH8_SACCH8C] = NM_CHANC_SDCCH,
+	[GSM_PCHAN_PDCH]	= NM_CHANC_IPAC_PDCH,
+	[GSM_PCHAN_TCH_F_PDCH]	= NM_CHANC_IPAC_TCHFull_PDCH,
+	/* FIXME: bounds check */
+};
+
+int abis_nm_chcomb4pchan(enum gsm_phys_chan_config pchan)
+{
+	if (pchan < ARRAY_SIZE(chcomb4pchan))
+		return chcomb4pchan[pchan];
+
+	return -EINVAL;
+}
+
+enum abis_nm_chan_comb abis_nm_pchan4chcomb(uint8_t chcomb)
+{
+	int i;
+	for (i = 0; i < ARRAY_SIZE(chcomb4pchan); i++) {
+		if (chcomb4pchan[i] == chcomb)
+			return i;
+	}
+	return GSM_PCHAN_NONE;
+}
diff --git a/src/gsm/sysinfo.c b/src/gsm/sysinfo.c
new file mode 100644
index 0000000..0dbff3a
--- /dev/null
+++ b/src/gsm/sysinfo.c
@@ -0,0 +1,131 @@
+/* GSM 04.08 System Information (SI) encoding and decoding
+ * 3GPP TS 04.08 version 7.21.0 Release 1998 / ETSI TS 100 940 V7.21.0 */
+
+/* (C) 2008-2010 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 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, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include <errno.h>
+#include <string.h>
+#include <stdio.h>
+#include <netinet/in.h>
+
+#include <osmocom/core/bitvec.h>
+#include <osmocom/core/utils.h>
+#include <osmocom/gsm/sysinfo.h>
+#include <osmocom/gsm/protocol/gsm_04_08.h>
+#include <osmocom/gsm/protocol/gsm_08_58.h>
+
+/* verify the sizes of the system information type structs */
+
+/* rest octets are not part of the struct */
+osmo_static_assert(sizeof(struct gsm48_system_information_type_header) == 3, _si_header_size);
+osmo_static_assert(sizeof(struct gsm48_rach_control) == 3, _si_rach_control);
+osmo_static_assert(sizeof(struct gsm48_system_information_type_1) == 22, _si1_size);
+osmo_static_assert(sizeof(struct gsm48_system_information_type_2) == 23, _si2_size);
+osmo_static_assert(sizeof(struct gsm48_system_information_type_3) == 19, _si3_size);
+osmo_static_assert(sizeof(struct gsm48_system_information_type_4) == 13, _si4_size);
+
+/* bs11 forgot the l2 len, 0-6 rest octets */
+osmo_static_assert(sizeof(struct gsm48_system_information_type_5) == 18, _si5_size);
+osmo_static_assert(sizeof(struct gsm48_system_information_type_6) == 11, _si6_size);
+
+osmo_static_assert(sizeof(struct gsm48_system_information_type_13) == 3, _si13_size);
+
+static const uint8_t sitype2rsl[_MAX_SYSINFO_TYPE] = {
+	[SYSINFO_TYPE_1]	= RSL_SYSTEM_INFO_1,
+	[SYSINFO_TYPE_2]	= RSL_SYSTEM_INFO_2,
+	[SYSINFO_TYPE_3]	= RSL_SYSTEM_INFO_3,
+	[SYSINFO_TYPE_4]	= RSL_SYSTEM_INFO_4,
+	[SYSINFO_TYPE_5]	= RSL_SYSTEM_INFO_5,
+	[SYSINFO_TYPE_6]	= RSL_SYSTEM_INFO_6,
+	[SYSINFO_TYPE_7]	= RSL_SYSTEM_INFO_7,
+	[SYSINFO_TYPE_8]	= RSL_SYSTEM_INFO_8,
+	[SYSINFO_TYPE_9]	= RSL_SYSTEM_INFO_9,
+	[SYSINFO_TYPE_10]	= RSL_SYSTEM_INFO_10,
+	[SYSINFO_TYPE_13]	= RSL_SYSTEM_INFO_13,
+	[SYSINFO_TYPE_16]	= RSL_SYSTEM_INFO_16,
+	[SYSINFO_TYPE_17]	= RSL_SYSTEM_INFO_17,
+	[SYSINFO_TYPE_18]	= RSL_SYSTEM_INFO_18,
+	[SYSINFO_TYPE_19]	= RSL_SYSTEM_INFO_19,
+	[SYSINFO_TYPE_20]	= RSL_SYSTEM_INFO_20,
+	[SYSINFO_TYPE_2bis]	= RSL_SYSTEM_INFO_2bis,
+	[SYSINFO_TYPE_2ter]	= RSL_SYSTEM_INFO_2ter,
+	[SYSINFO_TYPE_2quater]	= RSL_SYSTEM_INFO_2quater,
+	[SYSINFO_TYPE_5bis]	= RSL_SYSTEM_INFO_5bis,
+	[SYSINFO_TYPE_5ter]	= RSL_SYSTEM_INFO_5ter,
+};
+
+static const uint8_t rsl2sitype[0xff] = {
+	[RSL_SYSTEM_INFO_1] = SYSINFO_TYPE_1,
+	[RSL_SYSTEM_INFO_2] = SYSINFO_TYPE_2,
+	[RSL_SYSTEM_INFO_3] = SYSINFO_TYPE_3,
+	[RSL_SYSTEM_INFO_4] = SYSINFO_TYPE_4,
+	[RSL_SYSTEM_INFO_5] = SYSINFO_TYPE_5,
+	[RSL_SYSTEM_INFO_6] = SYSINFO_TYPE_6,
+	[RSL_SYSTEM_INFO_7] = SYSINFO_TYPE_7,
+	[RSL_SYSTEM_INFO_8] = SYSINFO_TYPE_8,
+	[RSL_SYSTEM_INFO_9] = SYSINFO_TYPE_9,
+	[RSL_SYSTEM_INFO_10] = SYSINFO_TYPE_10,
+	[RSL_SYSTEM_INFO_13] = SYSINFO_TYPE_13,
+	[RSL_SYSTEM_INFO_16] = SYSINFO_TYPE_16,
+	[RSL_SYSTEM_INFO_17] = SYSINFO_TYPE_17,
+	[RSL_SYSTEM_INFO_18] = SYSINFO_TYPE_18,
+	[RSL_SYSTEM_INFO_19] = SYSINFO_TYPE_19,
+	[RSL_SYSTEM_INFO_20] = SYSINFO_TYPE_20,
+	[RSL_SYSTEM_INFO_2bis] = SYSINFO_TYPE_2bis,
+	[RSL_SYSTEM_INFO_2ter] = SYSINFO_TYPE_2ter,
+	[RSL_SYSTEM_INFO_2quater] = SYSINFO_TYPE_2quater,
+	[RSL_SYSTEM_INFO_5bis] = SYSINFO_TYPE_5bis,
+	[RSL_SYSTEM_INFO_5ter] = SYSINFO_TYPE_5ter,
+};
+
+const struct value_string osmo_sitype_strs[_MAX_SYSINFO_TYPE] = {
+	{ SYSINFO_TYPE_1,	"1" },
+	{ SYSINFO_TYPE_2,	"2" },
+	{ SYSINFO_TYPE_3,	"3" },
+	{ SYSINFO_TYPE_4,	"4" },
+	{ SYSINFO_TYPE_5,	"5" },
+	{ SYSINFO_TYPE_6,	"6" },
+	{ SYSINFO_TYPE_7,	"7" },
+	{ SYSINFO_TYPE_8,	"8" },
+	{ SYSINFO_TYPE_9,	"9" },
+	{ SYSINFO_TYPE_10,	"10" },
+	{ SYSINFO_TYPE_13,	"13" },
+	{ SYSINFO_TYPE_16,	"16" },
+	{ SYSINFO_TYPE_17,	"17" },
+	{ SYSINFO_TYPE_18,	"18" },
+	{ SYSINFO_TYPE_19,	"19" },
+	{ SYSINFO_TYPE_20,	"20" },
+	{ SYSINFO_TYPE_2bis,	"2bis" },
+	{ SYSINFO_TYPE_2ter,	"2ter" },
+	{ SYSINFO_TYPE_2quater,	"2quater" },
+	{ SYSINFO_TYPE_5bis,	"5bis" },
+	{ SYSINFO_TYPE_5ter,	"5ter" },
+	{ 0, NULL }
+};
+
+uint8_t osmo_sitype2rsl(enum osmo_sysinfo_type si_type)
+{
+	return sitype2rsl[si_type];
+}
+
+enum osmo_sysinfo_type osmo_rsl2sitype(uint8_t rsl_si)
+{
+	return rsl2sitype[rsl_si];
+}