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osmo-bsc/src/libbsc/system_information.c

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/* 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>
* (C) 2012 Holger Hans Peter Freyther
*
* 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/licenses/>.
*
*/
#include <errno.h>
#include <string.h>
#include <stdio.h>
#include <netinet/in.h>
#include <stdbool.h>
#include <osmocom/core/bitvec.h>
#include <osmocom/core/utils.h>
#include <osmocom/gsm/sysinfo.h>
#include <openbsc/debug.h>
#include <openbsc/gsm_04_08.h>
#include <openbsc/gsm_data.h>
#include <openbsc/abis_rsl.h>
#include <openbsc/rest_octets.h>
#include <openbsc/arfcn_range_encode.h>
/*
* DCS1800 and PCS1900 have overlapping ARFCNs. We would need to set the
* ARFCN_PCS flag on the 1900 ARFCNs but this would increase cell_alloc
* and other arrays to make sure (ARFCN_PCS + 1024)/8 ARFCNs fit into the
* array. DCS1800 and PCS1900 can not be used at the same time so conserve
* memory and do the below.
*/
static int band_compatible(const struct gsm_bts *bts, int arfcn)
{
enum gsm_band band = gsm_arfcn2band(arfcn);
/* normal case */
if (band == bts->band)
return 1;
/* deal with ARFCN_PCS not set */
if (band == GSM_BAND_1800 && bts->band == GSM_BAND_1900)
return 1;
return 0;
}
static int is_dcs_net(const struct gsm_bts *bts)
{
if (bts->band == GSM_BAND_850)
return 0;
if (bts->band == GSM_BAND_1900)
return 0;
return 1;
}
/* Return p(n) for given NR_OF_TDD_CELLS - see Table 9.1.54.1a, 3GPP TS 44.018 */
unsigned range1024_p(unsigned n)
{
switch (n) {
case 0: return 0;
case 1: return 10;
case 2: return 19;
case 3: return 28;
case 4: return 36;
case 5: return 44;
case 6: return 52;
case 7: return 60;
case 8: return 67;
case 9: return 74;
case 10: return 81;
case 11: return 88;
case 12: return 95;
case 13: return 102;
case 14: return 109;
case 15: return 116;
case 16: return 122;
default: return 0;
}
}
/* Return q(m) for given NR_OF_TDD_CELLS - see Table 9.1.54.1b, 3GPP TS 44.018 */
unsigned range512_q(unsigned m)
{
switch (m) {
case 0: return 0;
case 1: return 9;
case 2: return 17;
case 3: return 25;
case 4: return 32;
case 5: return 39;
case 6: return 46;
case 7: return 53;
case 8: return 59;
case 9: return 65;
case 10: return 71;
case 11: return 77;
case 12: return 83;
case 13: return 89;
case 14: return 95;
case 15: return 101;
case 16: return 106;
case 17: return 111;
case 18: return 116;
case 19: return 121;
case 20: return 126;
default: return 0;
}
}
size_t si2q_earfcn_count(const struct osmo_earfcn_si2q *e)
{
unsigned i, ret = 0;
if (!e)
return 0;
for (i = 0; i < e->length; i++)
if (e->arfcn[i] != OSMO_EARFCN_INVALID)
ret++;
return ret;
}
/* generate SI2quater messages, return rest octets length of last generated message or negative error code */
static int make_si2quaters(struct gsm_bts *bts, bool counting)
{
int rc;
bool memory_exceeded = true;
struct gsm48_system_information_type_2quater *si2q;
for (bts->si2q_index = 0; bts->si2q_index < SI2Q_MAX_NUM; bts->si2q_index++) {
si2q = GSM_BTS_SI2Q(bts, bts->si2q_index);
if (counting) { /* that's legitimate if we're called for counting purpose: */
if (bts->si2q_count < bts->si2q_index)
bts->si2q_count = bts->si2q_index;
} else {
memset(si2q, GSM_MACBLOCK_PADDING, GSM_MACBLOCK_LEN);
si2q->header.l2_plen = GSM48_LEN2PLEN(22);
si2q->header.rr_protocol_discriminator = GSM48_PDISC_RR;
si2q->header.skip_indicator = 0;
si2q->header.system_information = GSM48_MT_RR_SYSINFO_2quater;
}
rc = rest_octets_si2quater(si2q->rest_octets, bts);
if (rc < 0)
return rc;
if (bts->u_offset >= bts->si_common.uarfcn_length &&
bts->e_offset >= si2q_earfcn_count(&bts->si_common.si2quater_neigh_list)) {
memory_exceeded = false;
break;
}
}
if (memory_exceeded)
return -ENOMEM;
return rc;
}
/* we generate SI2q rest octets twice to get proper estimation but it's one time cost anyway */
uint8_t si2q_num(struct gsm_bts *bts)
{
int rc = make_si2quaters(bts, true);
uint8_t num = bts->si2q_index + 1; /* number of SI2quater messages */
/* N. B: si2q_num() should NEVER be called during actualSI2q rest octets generation
we're not re-entrant because of the following code: */
bts->u_offset = 0;
bts->e_offset = 0;
if (rc < 0)
return 0xFF; /* return impossible index as an indicator of error in generating SI2quater */
return num;
}
/* 3GPP TS 44.018, Table 9.1.54.1 - prepend diversity bit to scrambling code */
static inline uint16_t encode_fdd(uint16_t scramble, bool diversity)
{
if (diversity)
return scramble | (1 << 9);
return scramble;
}
int bts_earfcn_add(struct gsm_bts *bts, uint16_t earfcn, uint8_t thresh_hi, uint8_t thresh_lo, uint8_t prio,
uint8_t qrx, uint8_t meas_bw)
{
struct osmo_earfcn_si2q *e = &bts->si_common.si2quater_neigh_list;
int r = osmo_earfcn_add(e, earfcn, (meas_bw < EARFCN_MEAS_BW_INVALID) ? meas_bw : OSMO_EARFCN_MEAS_INVALID);
if (r < 0)
return r;
if (e->thresh_hi && thresh_hi != e->thresh_hi)
r = 1;
e->thresh_hi = thresh_hi;
if (thresh_lo != EARFCN_THRESH_LOW_INVALID) {
if (e->thresh_lo_valid && e->thresh_lo != thresh_lo)
r = EARFCN_THRESH_LOW_INVALID;
e->thresh_lo = thresh_lo;
e->thresh_lo_valid = true;
}
if (qrx != EARFCN_QRXLV_INVALID) {
if (e->qrxlm_valid && e->qrxlm != qrx)
r = EARFCN_QRXLV_INVALID + 1;
e->qrxlm = qrx;
e->qrxlm_valid = true;
}
if (prio != EARFCN_PRIO_INVALID) {
if (e->prio_valid && e->prio != prio)
r = EARFCN_PRIO_INVALID;
e->prio = prio;
e->prio_valid = true;
}
return r;
}
int bts_uarfcn_del(struct gsm_bts *bts, uint16_t arfcn, uint16_t scramble)
{
uint16_t sc0 = encode_fdd(scramble, false), sc1 = encode_fdd(scramble, true),
*ual = bts->si_common.data.uarfcn_list,
*scl = bts->si_common.data.scramble_list;
size_t len = bts->si_common.uarfcn_length, i;
for (i = 0; i < len; i++) {
if (arfcn == ual[i] && (sc0 == scl[i] || sc1 == scl[i])) {
/* we rely on the assumption that (uarfcn, scramble)
tuple is unique in the lists */
if (i != len - 1) { /* move the tail if necessary */
memmove(ual + i, ual + i + 1, 2 * (len - i + 1));
memmove(scl + i, scl + i + 1, 2 * (len - i + 1));
}
break;
}
}
if (i == len)
return -EINVAL;
bts->si_common.uarfcn_length--;
return 0;
}
int bts_uarfcn_add(struct gsm_bts *bts, uint16_t arfcn, uint16_t scramble, bool diversity)
{
size_t len = bts->si_common.uarfcn_length, i, k = 0;
uint16_t scr, chk,
*ual = bts->si_common.data.uarfcn_list,
*scl = bts->si_common.data.scramble_list,
scramble1 = encode_fdd(scramble, true),
scramble0 = encode_fdd(scramble, false);
scr = diversity ? scramble1 : scramble0;
chk = diversity ? scramble0 : scramble1;
if (len == MAX_EARFCN_LIST)
return -ENOMEM;
for (i = 0; i < len; i++) /* find the position of arfcn if any */
if (arfcn == ual[i])
break;
for (k = 0; i < len; i++) {
if (arfcn == ual[i] && (scr == scl[i] || chk == scl[i]))
return -EADDRINUSE;
if (scr > scl[i])
k = i + 1;
}
/* we keep lists sorted by scramble code:
insert into appropriate position and move the tail */
if (len - k) {
memmove(ual + k + 1, ual + k, (len - k) * 2);
memmove(scl + k + 1, scl + k, (len - k) * 2);
}
ual[k] = arfcn;
scl[k] = scr;
bts->si_common.uarfcn_length++;
if (si2q_num(bts) <= SI2Q_MAX_NUM) {
bts->si2q_count = si2q_num(bts) - 1;
return 0;
}
bts_uarfcn_del(bts, arfcn, scramble);
return -ENOSPC;
}
static inline int use_arfcn(const struct gsm_bts *bts, const bool bis, const bool ter,
const bool pgsm, const int arfcn)
{
if (bts->force_combined_si)
return !bis && !ter;
if (!bis && !ter && band_compatible(bts, arfcn))
return 1;
/* Correct but somehow broken with either the nanoBTS or the iPhone5 */
if (bis && pgsm && band_compatible(bts, arfcn) && (arfcn < 1 || arfcn > 124))
return 1;
if (ter && !band_compatible(bts, arfcn))
return 1;
return 0;
}
/* Frequency Lists as per TS 04.08 10.5.2.13 */
/* 10.5.2.13.2: Bit map 0 format */
static int freq_list_bm0_set_arfcn(uint8_t *chan_list, unsigned int arfcn)
{
unsigned int byte, bit;
if (arfcn > 124 || arfcn < 1) {
LOGP(DRR, LOGL_ERROR, "Bitmap 0 only supports ARFCN 1...124\n");
return -EINVAL;
}
/* the bitmask is from 1..124, not from 0..123 */
arfcn--;
byte = arfcn / 8;
bit = arfcn % 8;
chan_list[GSM48_CELL_CHAN_DESC_SIZE-1-byte] |= (1 << bit);
return 0;
}
/* 10.5.2.13.7: Variable bit map format */
static int freq_list_bmrel_set_arfcn(uint8_t *chan_list, unsigned int arfcn)
{
unsigned int byte, bit;
unsigned int min_arfcn;
unsigned int bitno;
min_arfcn = (chan_list[0] & 1) << 9;
min_arfcn |= chan_list[1] << 1;
min_arfcn |= (chan_list[2] >> 7) & 1;
/* The lower end of our bitmaks is always implicitly included */
if (arfcn == min_arfcn)
return 0;
if (((arfcn - min_arfcn) & 1023) > 111) {
LOGP(DRR, LOGL_ERROR, "arfcn(%u) > min(%u) + 111\n", arfcn, min_arfcn);
return -EINVAL;
}
bitno = (arfcn - min_arfcn) & 1023;
byte = bitno / 8;
bit = bitno % 8;
chan_list[2 + byte] |= 1 << (7 - bit);
return 0;
}
/* generate a variable bitmap */
static inline int enc_freq_lst_var_bitmap(uint8_t *chan_list,
struct bitvec *bv, const struct gsm_bts *bts,
bool bis, bool ter, int min, bool pgsm)
{
int i;
/* set it to 'Variable bitmap format' */
chan_list[0] = 0x8e;
chan_list[0] |= (min >> 9) & 1;
chan_list[1] = (min >> 1);
chan_list[2] = (min & 1) << 7;
for (i = 0; i < bv->data_len*8; i++) {
/* see notes in bitvec2freq_list */
if (bitvec_get_bit_pos(bv, i)
&& ((!bis && !ter && band_compatible(bts,i))
|| (bis && pgsm && band_compatible(bts,i) && (i < 1 || i > 124))
|| (ter && !band_compatible(bts, i)))) {
int rc = freq_list_bmrel_set_arfcn(chan_list, i);
if (rc < 0)
return rc;
}
}
return 0;
}
int range_encode(enum gsm48_range r, int *arfcns, int arfcns_used, int *w,
int f0, uint8_t *chan_list)
{
/*
* Manipulate the ARFCN list according to the rules in J4 depending
* on the selected range.
*/
int rc, f0_included;
range_enc_filter_arfcns(arfcns, arfcns_used, f0, &f0_included);
rc = range_enc_arfcns(r, arfcns, arfcns_used, w, 0);
if (rc < 0)
return rc;
/* Select the range and the amount of bits needed */
switch (r) {
case ARFCN_RANGE_128:
return range_enc_range128(chan_list, f0, w);
case ARFCN_RANGE_256:
return range_enc_range256(chan_list, f0, w);
case ARFCN_RANGE_512:
return range_enc_range512(chan_list, f0, w);
case ARFCN_RANGE_1024:
return range_enc_range1024(chan_list, f0, f0_included, w);
default:
return -ERANGE;
};
return f0_included;
}
/* generate a frequency list with the range 512 format */
static inline int enc_freq_lst_range(uint8_t *chan_list,
struct bitvec *bv, const struct gsm_bts *bts,
bool bis, bool ter, bool pgsm)
{
int arfcns[RANGE_ENC_MAX_ARFCNS];
int w[RANGE_ENC_MAX_ARFCNS];
int arfcns_used = 0;
int i, range, f0;
/*
* Select ARFCNs according to the rules in bitvec2freq_list
*/
for (i = 0; i < bv->data_len * 8; ++i) {
/* More ARFCNs than the maximum */
if (arfcns_used > ARRAY_SIZE(arfcns))
return -1;
/* Check if we can select it? */
if (bitvec_get_bit_pos(bv, i) && use_arfcn(bts, bis, ter, pgsm, i))
arfcns[arfcns_used++] = i;
}
/*
* Check if the given list of ARFCNs can be encoded.
*/
range = range_enc_determine_range(arfcns, arfcns_used, &f0);
if (range == ARFCN_RANGE_INVALID)
return -2;
memset(w, 0, sizeof(w));
return range_encode(range, arfcns, arfcns_used, w, f0, chan_list);
}
/* generate a cell channel list as per Section 10.5.2.1b of 04.08 */
static int bitvec2freq_list(uint8_t *chan_list, struct bitvec *bv,
const struct gsm_bts *bts, bool bis, bool ter)
{
int i, rc, min = -1, max = -1, arfcns = 0;
bool pgsm = false;
memset(chan_list, 0, 16);
if (bts->band == GSM_BAND_900
&& bts->c0->arfcn >= 1 && bts->c0->arfcn <= 124)
pgsm = true;
/* P-GSM-only handsets only support 'bit map 0 format' */
if (!bis && !ter && pgsm) {
chan_list[0] = 0;
for (i = 0; i < bv->data_len*8; i++) {
if (i >= 1 && i <= 124
&& bitvec_get_bit_pos(bv, i)) {
rc = freq_list_bm0_set_arfcn(chan_list, i);
if (rc < 0)
return rc;
}
}
return 0;
}
for (i = 0; i < bv->data_len*8; i++) {
/* in case of SI2 or SI5 allow all neighbours in same band
* in case of SI*bis, allow neighbours in same band ouside pgsm
* in case of SI*ter, allow neighbours in different bands
*/
if (!bitvec_get_bit_pos(bv, i))
continue;
if (!use_arfcn(bts, bis, ter, pgsm, i))
continue;
/* count the arfcns we want to carry */
arfcns += 1;
/* 955..1023 < 0..885 */
if (min < 0)
min = i;
if (i >= 955 && min < 955)
min = i;
if (i >= 955 && min >= 955 && i < min)
min = i;
if (i < 955 && min < 955 && i < min)
min = i;
if (max < 0)
max = i;
if (i < 955 && max >= 955)
max = i;
if (i >= 955 && max >= 955 && i > max)
max = i;
if (i < 955 && max < 955 && i > max)
max = i;
}
if (max == -1) {
/* Empty set, use 'bit map 0 format' */
chan_list[0] = 0;
return 0;
}
/* Now find the best encoding */
if (((max - min) & 1023) <= 111)
return enc_freq_lst_var_bitmap(chan_list, bv, bts, bis,
ter, min, pgsm);
/* Attempt to do the range encoding */
rc = enc_freq_lst_range(chan_list, bv, bts, bis, ter, pgsm);
if (rc >= 0)
return 0;
LOGP(DRR, LOGL_ERROR, "min_arfcn=%u, max_arfcn=%u, arfcns=%d "
"can not generate ARFCN list", min, max, arfcns);
return -EINVAL;
}
/* generate a cell channel list as per Section 10.5.2.1b of 04.08 */
/* static*/ int generate_cell_chan_list(uint8_t *chan_list, struct gsm_bts *bts)
{
struct gsm_bts_trx *trx;
struct bitvec *bv = &bts->si_common.cell_alloc;
/* Zero-initialize the bit-vector */
memset(bv->data, 0, bv->data_len);
/* first we generate a bitvec of all TRX ARFCN's in our BTS */
llist_for_each_entry(trx, &bts->trx_list, list) {
unsigned int i, j;
/* Always add the TRX's ARFCN */
bitvec_set_bit_pos(bv, trx->arfcn, 1);
for (i = 0; i < ARRAY_SIZE(trx->ts); i++) {
struct gsm_bts_trx_ts *ts = &trx->ts[i];
/* Add any ARFCNs present in hopping channels */
for (j = 0; j < 1024; j++) {
if (bitvec_get_bit_pos(&ts->hopping.arfcns, j))
bitvec_set_bit_pos(bv, j, 1);
}
}
}
/* then we generate a GSM 04.08 frequency list from the bitvec */
return bitvec2freq_list(chan_list, bv, bts, false, false);
}
/* generate a cell channel list as per Section 10.5.2.1b of 04.08 */
static int generate_bcch_chan_list(uint8_t *chan_list, struct gsm_bts *bts,
bool si5, bool bis, bool ter)
{
struct gsm_bts *cur_bts;
struct bitvec *bv;
if (si5 && bts->neigh_list_manual_mode == NL_MODE_MANUAL_SI5SEP)
bv = &bts->si_common.si5_neigh_list;
else
bv = &bts->si_common.neigh_list;
/* Generate list of neighbor cells if we are in automatic mode */
if (bts->neigh_list_manual_mode == NL_MODE_AUTOMATIC) {
/* Zero-initialize the bit-vector */
memset(bv->data, 0, bv->data_len);
/* first we generate a bitvec of the BCCH ARFCN's in our BSC */
llist_for_each_entry(cur_bts, &bts->network->bts_list, list) {
if (cur_bts == bts)
continue;
bitvec_set_bit_pos(bv, cur_bts->c0->arfcn, 1);
}
}
/* then we generate a GSM 04.08 frequency list from the bitvec */
return bitvec2freq_list(chan_list, bv, bts, bis, ter);
}
static int list_arfcn(uint8_t *chan_list, uint8_t mask, char *text)
{
int n = 0, i;
struct gsm_sysinfo_freq freq[1024];
memset(freq, 0, sizeof(freq));
gsm48_decode_freq_list(freq, chan_list, 16, 0xce, 1);
for (i = 0; i < 1024; i++) {
if (freq[i].mask) {
if (!n)
LOGP(DRR, LOGL_INFO, "%s", text);
LOGPC(DRR, LOGL_INFO, " %d", i);
n++;
}
}
if (n)
LOGPC(DRR, LOGL_INFO, "\n");
return n;
}
static int generate_si1(enum osmo_sysinfo_type t, struct gsm_bts *bts)
{
int rc;
struct gsm48_system_information_type_1 *si1 = (struct gsm48_system_information_type_1 *) GSM_BTS_SI(bts, t);
memset(si1, GSM_MACBLOCK_PADDING, GSM_MACBLOCK_LEN);
si1->header.l2_plen = GSM48_LEN2PLEN(21);
si1->header.rr_protocol_discriminator = GSM48_PDISC_RR;
si1->header.skip_indicator = 0;
si1->header.system_information = GSM48_MT_RR_SYSINFO_1;
rc = generate_cell_chan_list(si1->cell_channel_description, bts);
if (rc < 0)
return rc;
list_arfcn(si1->cell_channel_description, 0xce, "Serving cell:");
si1->rach_control = bts->si_common.rach_control;
/*
* SI1 Rest Octets (10.5.2.32), contains NCH position and band
* indicator but that is not in the 04.08.
*/
rc = rest_octets_si1(si1->rest_octets, NULL, is_dcs_net(bts));
return sizeof(*si1) + rc;
}
static int generate_si2(enum osmo_sysinfo_type t, struct gsm_bts *bts)
{
int rc;
struct gsm48_system_information_type_2 *si2 = (struct gsm48_system_information_type_2 *) GSM_BTS_SI(bts, t);
memset(si2, GSM_MACBLOCK_PADDING, GSM_MACBLOCK_LEN);
si2->header.l2_plen = GSM48_LEN2PLEN(22);
si2->header.rr_protocol_discriminator = GSM48_PDISC_RR;
si2->header.skip_indicator = 0;
si2->header.system_information = GSM48_MT_RR_SYSINFO_2;
rc = generate_bcch_chan_list(si2->bcch_frequency_list, bts, false, false, false);
if (rc < 0)
return rc;
list_arfcn(si2->bcch_frequency_list, 0xce,
"SI2 Neighbour cells in same band:");
si2->ncc_permitted = bts->si_common.ncc_permitted;
si2->rach_control = bts->si_common.rach_control;
return sizeof(*si2);
}
static int generate_si2bis(enum osmo_sysinfo_type t, struct gsm_bts *bts)
{
int rc;
struct gsm48_system_information_type_2bis *si2b =
(struct gsm48_system_information_type_2bis *) GSM_BTS_SI(bts, t);
int n;
memset(si2b, GSM_MACBLOCK_PADDING, GSM_MACBLOCK_LEN);
si2b->header.l2_plen = GSM48_LEN2PLEN(22);
si2b->header.rr_protocol_discriminator = GSM48_PDISC_RR;
si2b->header.skip_indicator = 0;
si2b->header.system_information = GSM48_MT_RR_SYSINFO_2bis;
rc = generate_bcch_chan_list(si2b->bcch_frequency_list, bts, false, true, false);
if (rc < 0)
return rc;
n = list_arfcn(si2b->bcch_frequency_list, 0xce,
"Neighbour cells in same band, but outside P-GSM:");
if (n) {
/* indicate in SI2 and SI2bis: there is an extension */
struct gsm48_system_information_type_2 *si2 =
(struct gsm48_system_information_type_2 *) GSM_BTS_SI(bts, SYSINFO_TYPE_2);
si2->bcch_frequency_list[0] |= 0x20;
si2b->bcch_frequency_list[0] |= 0x20;
} else
bts->si_valid &= ~(1 << SYSINFO_TYPE_2bis);
si2b->rach_control = bts->si_common.rach_control;
return sizeof(*si2b);
}
static int generate_si2ter(enum osmo_sysinfo_type t, struct gsm_bts *bts)
{
int rc;
struct gsm48_system_information_type_2ter *si2t =
(struct gsm48_system_information_type_2ter *) GSM_BTS_SI(bts, t);
int n;
memset(si2t, GSM_MACBLOCK_PADDING, GSM_MACBLOCK_LEN);
si2t->header.l2_plen = GSM48_LEN2PLEN(22);
si2t->header.rr_protocol_discriminator = GSM48_PDISC_RR;
si2t->header.skip_indicator = 0;
si2t->header.system_information = GSM48_MT_RR_SYSINFO_2ter;
rc = generate_bcch_chan_list(si2t->ext_bcch_frequency_list, bts, false, false, true);
if (rc < 0)
return rc;
n = list_arfcn(si2t->ext_bcch_frequency_list, 0x8e,
"Neighbour cells in different band:");
if (!n)
bts->si_valid &= ~(1 << SYSINFO_TYPE_2ter);
return sizeof(*si2t);
}
/* SI2quater messages are optional - we only generate them when neighbor UARFCNs or EARFCNs are configured */
static inline bool si2quater_not_needed(struct gsm_bts *bts)
{
unsigned i = MAX_EARFCN_LIST;
if (bts->si_common.si2quater_neigh_list.arfcn)
for (i = 0; i < MAX_EARFCN_LIST; i++)
if (bts->si_common.si2quater_neigh_list.arfcn[i] != OSMO_EARFCN_INVALID)
break;
if (!bts->si_common.uarfcn_length && i == MAX_EARFCN_LIST) {
bts->si_valid &= ~(1 << SYSINFO_TYPE_2quater); /* mark SI2q as invalid if no (E|U)ARFCNs are present */
return true;
}
return false;
}
static int generate_si2quater(enum osmo_sysinfo_type t, struct gsm_bts *bts)
{
int rc;
struct gsm48_system_information_type_2quater *si2q;
if (si2quater_not_needed(bts)) /* generate rest_octets for SI2q only when necessary */
return GSM_MACBLOCK_LEN;
bts->u_offset = 0;
bts->e_offset = 0;
bts->si2q_index = 0;
bts->si2q_count = si2q_num(bts) - 1;
rc = make_si2quaters(bts, false);
if (rc < 0)
return rc;
OSMO_ASSERT(bts->si2q_count == bts->si2q_index);
OSMO_ASSERT(bts->si2q_count <= SI2Q_MAX_NUM);
return sizeof(*si2q) + rc;
}
static struct gsm48_si_ro_info si_info = {
.selection_params = {
.present = 0,
},
.power_offset = {
.present = 0,
},
.si2ter_indicator = 0,
.early_cm_ctrl = 1,
.scheduling = {
.present = 0,
},
.gprs_ind = {
.si13_position = 0,
.ra_colour = 0,
.present = 1,
},
.si2quater_indicator = 0,
.lsa_params = {
.present = 0,
},
.cell_id = 0, /* FIXME: doesn't the bts have this? */
.break_ind = 0,
};
static int generate_si3(enum osmo_sysinfo_type t, struct gsm_bts *bts)
{
int rc;
struct gsm48_system_information_type_3 *si3 = (struct gsm48_system_information_type_3 *) GSM_BTS_SI(bts, t);
memset(si3, GSM_MACBLOCK_PADDING, GSM_MACBLOCK_LEN);
si3->header.l2_plen = GSM48_LEN2PLEN(18);
si3->header.rr_protocol_discriminator = GSM48_PDISC_RR;
si3->header.skip_indicator = 0;
si3->header.system_information = GSM48_MT_RR_SYSINFO_3;
si3->cell_identity = htons(bts->cell_identity);
gsm48_generate_lai(&si3->lai, bts->network->country_code,
bts->network->network_code,
bts->location_area_code);
si3->control_channel_desc = bts->si_common.chan_desc;
si3->cell_options = bts->si_common.cell_options;
si3->cell_sel_par = bts->si_common.cell_sel_par;
si3->rach_control = bts->si_common.rach_control;
/* allow/disallow DTXu */
gsm48_set_dtx(&si3->cell_options, bts->dtxu, bts->dtxu, true);
if (GSM_BTS_HAS_SI(bts, SYSINFO_TYPE_2ter)) {
LOGP(DRR, LOGL_INFO, "SI 2ter is included.\n");
si_info.si2ter_indicator = 1;
} else {
si_info.si2ter_indicator = 0;
}
if (GSM_BTS_HAS_SI(bts, SYSINFO_TYPE_2quater)) {
LOGP(DRR, LOGL_INFO, "SI 2quater is included, based on %zu EARFCNs and %zu UARFCNs.\n",
si2q_earfcn_count(&bts->si_common.si2quater_neigh_list), bts->si_common.uarfcn_length);
si_info.si2quater_indicator = 1;
} else {
si_info.si2quater_indicator = 0;
}
si_info.early_cm_ctrl = bts->early_classmark_allowed;
/* SI3 Rest Octets (10.5.2.34), containing
CBQ, CELL_RESELECT_OFFSET, TEMPORARY_OFFSET, PENALTY_TIME
Power Offset, 2ter Indicator, Early Classmark Sending,
Scheduling if and WHERE, GPRS Indicator, SI13 position */
rc = rest_octets_si3(si3->rest_octets, &si_info);
return sizeof(*si3) + rc;
}
static int generate_si4(enum osmo_sysinfo_type t, struct gsm_bts *bts)
{
int rc;
struct gsm48_system_information_type_4 *si4 = (struct gsm48_system_information_type_4 *) GSM_BTS_SI(bts, t);
struct gsm_lchan *cbch_lchan;
uint8_t *restoct = si4->data;
/* length of all IEs present except SI4 rest octets and l2_plen */
int l2_plen = sizeof(*si4) - 1;
memset(si4, GSM_MACBLOCK_PADDING, GSM_MACBLOCK_LEN);
si4->header.rr_protocol_discriminator = GSM48_PDISC_RR;
si4->header.skip_indicator = 0;
si4->header.system_information = GSM48_MT_RR_SYSINFO_4;
gsm48_generate_lai(&si4->lai, bts->network->country_code,
bts->network->network_code,
bts->location_area_code);
si4->cell_sel_par = bts->si_common.cell_sel_par;
si4->rach_control = bts->si_common.rach_control;
/* Optional: CBCH Channel Description + CBCH Mobile Allocation */
cbch_lchan = gsm_bts_get_cbch(bts);
if (cbch_lchan) {
struct gsm48_chan_desc cd;
gsm48_lchan2chan_desc(&cd, cbch_lchan);
tv_fixed_put(si4->data, GSM48_IE_CBCH_CHAN_DESC, 3,
(uint8_t *) &cd);
l2_plen += 3 + 1;
restoct += 3 + 1;
/* we don't use hopping and thus don't need a CBCH MA */
}
si4->header.l2_plen = GSM48_LEN2PLEN(l2_plen);
/* SI4 Rest Octets (10.5.2.35), containing
Optional Power offset, GPRS Indicator,
Cell Identity, LSA ID, Selection Parameter */
rc = rest_octets_si4(restoct, &si_info, (uint8_t *)GSM_BTS_SI(bts, t) + GSM_MACBLOCK_LEN - restoct);
return l2_plen + 1 + rc;
}
static int generate_si5(enum osmo_sysinfo_type t, struct gsm_bts *bts)
{
struct gsm48_system_information_type_5 *si5;
uint8_t *output = GSM_BTS_SI(bts, t);
int rc, l2_plen = 18;
memset(output, GSM_MACBLOCK_PADDING, GSM_MACBLOCK_LEN);
/* ip.access nanoBTS needs l2_plen!! */
switch (bts->type) {
case GSM_BTS_TYPE_NANOBTS:
case GSM_BTS_TYPE_OSMOBTS:
*output++ = GSM48_LEN2PLEN(l2_plen);
l2_plen++;
break;
default:
break;
}
si5 = (struct gsm48_system_information_type_5 *) GSM_BTS_SI(bts, t);
/* l2 pseudo length, not part of msg: 18 */
si5->rr_protocol_discriminator = GSM48_PDISC_RR;
si5->skip_indicator = 0;
si5->system_information = GSM48_MT_RR_SYSINFO_5;
rc = generate_bcch_chan_list(si5->bcch_frequency_list, bts, true, false, false);
if (rc < 0)
return rc;
list_arfcn(si5->bcch_frequency_list, 0xce,
"SI5 Neighbour cells in same band:");
/* 04.08 9.1.37: L2 Pseudo Length of 18 */
return l2_plen;
}
static int generate_si5bis(enum osmo_sysinfo_type t, struct gsm_bts *bts)
{
struct gsm48_system_information_type_5bis *si5b;
uint8_t *output = GSM_BTS_SI(bts, t);
int rc, l2_plen = 18;
int n;
memset(output, GSM_MACBLOCK_PADDING, GSM_MACBLOCK_LEN);
/* ip.access nanoBTS needs l2_plen!! */
switch (bts->type) {
case GSM_BTS_TYPE_NANOBTS:
case GSM_BTS_TYPE_OSMOBTS:
*output++ = GSM48_LEN2PLEN(l2_plen);
l2_plen++;
break;
default:
break;
}
si5b = (struct gsm48_system_information_type_5bis *) GSM_BTS_SI(bts, t);
/* l2 pseudo length, not part of msg: 18 */
si5b->rr_protocol_discriminator = GSM48_PDISC_RR;
si5b->skip_indicator = 0;
si5b->system_information = GSM48_MT_RR_SYSINFO_5bis;
rc = generate_bcch_chan_list(si5b->bcch_frequency_list, bts, true, true, false);
if (rc < 0)
return rc;
n = list_arfcn(si5b->bcch_frequency_list, 0xce,
"Neighbour cells in same band, but outside P-GSM:");
if (n) {
/* indicate in SI5 and SI5bis: there is an extension */
struct gsm48_system_information_type_5 *si5 =
(struct gsm48_system_information_type_5 *) GSM_BTS_SI(bts, SYSINFO_TYPE_5);
si5->bcch_frequency_list[0] |= 0x20;
si5b->bcch_frequency_list[0] |= 0x20;
} else
bts->si_valid &= ~(1 << SYSINFO_TYPE_5bis);
/* 04.08 9.1.37: L2 Pseudo Length of 18 */
return l2_plen;
}
static int generate_si5ter(enum osmo_sysinfo_type t, struct gsm_bts *bts)
{
struct gsm48_system_information_type_5ter *si5t;
uint8_t *output = GSM_BTS_SI(bts, t);
int rc, l2_plen = 18;
int n;
memset(output, GSM_MACBLOCK_PADDING, GSM_MACBLOCK_LEN);
/* ip.access nanoBTS needs l2_plen!! */
switch (bts->type) {
case GSM_BTS_TYPE_NANOBTS:
case GSM_BTS_TYPE_OSMOBTS:
*output++ = GSM48_LEN2PLEN(l2_plen);
l2_plen++;
break;
default:
break;
}
si5t = (struct gsm48_system_information_type_5ter *) GSM_BTS_SI(bts, t);
/* l2 pseudo length, not part of msg: 18 */
si5t->rr_protocol_discriminator = GSM48_PDISC_RR;
si5t->skip_indicator = 0;
si5t->system_information = GSM48_MT_RR_SYSINFO_5ter;
rc = generate_bcch_chan_list(si5t->bcch_frequency_list, bts, true, false, true);
if (rc < 0)
return rc;
n = list_arfcn(si5t->bcch_frequency_list, 0x8e,
"Neighbour cells in different band:");
if (!n)
bts->si_valid &= ~(1 << SYSINFO_TYPE_5ter);
/* 04.08 9.1.37: L2 Pseudo Length of 18 */
return l2_plen;
}
static int generate_si6(enum osmo_sysinfo_type t, struct gsm_bts *bts)
{
struct gsm48_system_information_type_6 *si6;
uint8_t *output = GSM_BTS_SI(bts, t);
int l2_plen = 11;
int rc;
memset(output, GSM_MACBLOCK_PADDING, GSM_MACBLOCK_LEN);
/* ip.access nanoBTS needs l2_plen!! */
switch (bts->type) {
case GSM_BTS_TYPE_NANOBTS:
case GSM_BTS_TYPE_OSMOBTS:
*output++ = GSM48_LEN2PLEN(l2_plen);
l2_plen++;
break;
default:
break;
}
si6 = (struct gsm48_system_information_type_6 *) GSM_BTS_SI(bts, t);
/* l2 pseudo length, not part of msg: 11 */
si6->rr_protocol_discriminator = GSM48_PDISC_RR;
si6->skip_indicator = 0;
si6->system_information = GSM48_MT_RR_SYSINFO_6;
si6->cell_identity = htons(bts->cell_identity);
gsm48_generate_lai(&si6->lai, bts->network->country_code,
bts->network->network_code,
bts->location_area_code);
si6->cell_options = bts->si_common.cell_options;
si6->ncc_permitted = bts->si_common.ncc_permitted;
/* allow/disallow DTXu */
gsm48_set_dtx(&si6->cell_options, bts->dtxu, bts->dtxu, false);
/* SI6 Rest Octets: 10.5.2.35a: PCH / NCH info, VBS/VGCS options */
rc = rest_octets_si6(si6->rest_octets, is_dcs_net(bts));
return l2_plen + rc;
}
static struct gsm48_si13_info si13_default = {
.cell_opts = {
.nmo = GPRS_NMO_II,
.t3168 = 2000,
.t3192 = 1500,
.drx_timer_max = 3,
.bs_cv_max = 15,
.ctrl_ack_type_use_block = true,
.ext_info_present = 0,
.supports_egprs_11bit_rach = 0,
.ext_info = {
/* The values below are just guesses ! */
.egprs_supported = 0,
.use_egprs_p_ch_req = 1,
.bep_period = 5,
.pfc_supported = 0,
.dtm_supported = 0,
.bss_paging_coordination = 0,
},
},
.pwr_ctrl_pars = {
.alpha = 0, /* a = 0.0 */
.t_avg_w = 16,
.t_avg_t = 16,
.pc_meas_chan = 0, /* downling measured on CCCH */
.n_avg_i = 8,
},
.bcch_change_mark = 1,
.si_change_field = 0,
.pbcch_present = 0,
{
.no_pbcch = {
.rac = 0, /* needs to be patched */
.spgc_ccch_sup = 0,
.net_ctrl_ord = 0,
.prio_acc_thr = 6,
},
},
};
static int generate_si13(enum osmo_sysinfo_type t, struct gsm_bts *bts)
{
struct gsm48_system_information_type_13 *si13 =
(struct gsm48_system_information_type_13 *) GSM_BTS_SI(bts, t);
int ret;
memset(si13, GSM_MACBLOCK_PADDING, GSM_MACBLOCK_LEN);
si13->header.rr_protocol_discriminator = GSM48_PDISC_RR;
si13->header.skip_indicator = 0;
si13->header.system_information = GSM48_MT_RR_SYSINFO_13;
si13_default.no_pbcch.rac = bts->gprs.rac;
si13_default.no_pbcch.net_ctrl_ord = bts->gprs.net_ctrl_ord;
si13_default.cell_opts.ctrl_ack_type_use_block =
bts->gprs.ctrl_ack_type_use_block;
/* Information about the other SIs */
si13_default.bcch_change_mark = bts->bcch_change_mark;
si13_default.cell_opts.supports_egprs_11bit_rach =
bts->gprs.supports_egprs_11bit_rach;
ret = rest_octets_si13(si13->rest_octets, &si13_default);
if (ret < 0)
return ret;
/* length is coded in bit 2 an up */
si13->header.l2_plen = 0x01;
return sizeof (*si13) + ret;
}
typedef int (*gen_si_fn_t)(enum osmo_sysinfo_type t, struct gsm_bts *bts);
static const gen_si_fn_t gen_si_fn[_MAX_SYSINFO_TYPE] = {
[SYSINFO_TYPE_1] = &generate_si1,
[SYSINFO_TYPE_2] = &generate_si2,
[SYSINFO_TYPE_2bis] = &generate_si2bis,
[SYSINFO_TYPE_2ter] = &generate_si2ter,
[SYSINFO_TYPE_2quater] = &generate_si2quater,
[SYSINFO_TYPE_3] = &generate_si3,
[SYSINFO_TYPE_4] = &generate_si4,
[SYSINFO_TYPE_5] = &generate_si5,
[SYSINFO_TYPE_5bis] = &generate_si5bis,
[SYSINFO_TYPE_5ter] = &generate_si5ter,
[SYSINFO_TYPE_6] = &generate_si6,
[SYSINFO_TYPE_13] = &generate_si13,
};
int gsm_generate_si(struct gsm_bts *bts, enum osmo_sysinfo_type si_type)
{
gen_si_fn_t gen_si;
switch (bts->gprs.mode) {
case BTS_GPRS_EGPRS:
si13_default.cell_opts.ext_info_present = 1;
si13_default.cell_opts.ext_info.egprs_supported = 1;
/* fallthrough */
case BTS_GPRS_GPRS:
si_info.gprs_ind.present = 1;
break;
case BTS_GPRS_NONE:
si_info.gprs_ind.present = 0;
break;
}
memcpy(&si_info.selection_params,
&bts->si_common.cell_ro_sel_par,
sizeof(struct gsm48_si_selection_params));
gen_si = gen_si_fn[si_type];
if (!gen_si)
return -EINVAL;
return gen_si(si_type, bts);
}
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