Osmocom Packet control Unit (PCU): Network-side GPRS (RLC/MAC); BTS- or BSC-colocated https://osmocom.org/projects/osmopcu
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osmo-pcu/src/gprs_pcu.c

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7.4 KiB

/*
* Copyright (C) 2013 by Holger Hans Peter Freyther
* Copyright (C) 2021 by sysmocom - s.f.m.c. GmbH <info@sysmocom.de>
* Author: Pau Espin Pedrol <pespin@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 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 <osmocom/core/utils.h>
#include <osmocom/core/linuxlist.h>
#include <osmocom/ctrl/ports.h>
#include "gprs_pcu.h"
#include "bts.h"
struct gprs_pcu *the_pcu;
static struct osmo_tdef T_defs_pcu[] = {
{ .T=3113, .default_val=7, .unit=OSMO_TDEF_S, .desc="Timeout for paging", .val=0 },
{ .T=3190, .default_val=5, .unit=OSMO_TDEF_S, .desc="Return to packet idle mode after Packet DL Assignment on CCCH (s)", .val=0},
{ .T=3141, .default_val=10, .unit=OSMO_TDEF_S, .desc="Timeout for contention resolution procedure (s)", .val=0 },
{ .T=PCU_TDEF_NEIGH_RESOLVE_TO, .default_val=1000, .unit=OSMO_TDEF_MS, .desc="[ARFCN+BSIC]->[RAC+CI] resolution timeout (ms)", .val=0 },
{ .T=PCU_TDEF_SI_RESOLVE_TO, .default_val=1000, .unit=OSMO_TDEF_MS, .desc="RIM RAN-INFO response timeout (ms)", .val=0 },
{ .T=PCU_TDEF_NEIGH_CACHE_ALIVE, .default_val=5, .unit=OSMO_TDEF_S, .desc="[ARFCN+BSIC]->[RAC+CI] resolution cache entry storage timeout (s)", .val=0 },
{ .T=PCU_TDEF_SI_CACHE_ALIVE, .default_val=5, .unit=OSMO_TDEF_S, .desc="[RAC+CI]->[SI] resolution cache entry storage timeout (s)", .val=0 },
{ .T=-101, .default_val=30, .unit=OSMO_TDEF_S, .desc="BSSGP (un)blocking procedures timer (s)", .val=0 },
{ .T=-102, .default_val=30, .unit=OSMO_TDEF_S, .desc="BSSGP reset procedure timer (s)", .val=0 },
{ .T=-2000, .default_val=2, .unit=OSMO_TDEF_MS, .desc="Delay release of UL TBF after tx Packet Access Reject (PACCH) (ms)", .val=0 },
{ .T=-2001, .default_val=2, .unit=OSMO_TDEF_S, .desc="PACCH assignment timeout (s)", .val=0 },
{ .T=-2002, .default_val=200, .unit=OSMO_TDEF_MS, .desc="Waiting after IMM.ASS confirm timer (ms)", .val=0 },
{ .T=-2030, .default_val=60, .unit=OSMO_TDEF_S, .desc="Time to keep an idle MS object alive (s)", .val=0 }, /* slightly above T3314 (default 44s, 24.008, 11.2.2) */
{ .T=-2031, .default_val=2000, .unit=OSMO_TDEF_MS, .desc="Time to keep an idle DL TBF alive (ms)", .val=0 },
{ .T=0, .default_val=0, .unit=OSMO_TDEF_S, .desc=NULL, .val=0 } /* empty item at the end */
};
static int gprs_pcu_talloc_destructor(struct gprs_pcu *pcu)
{
neigh_cache_free(pcu->neigh_cache);
si_cache_free(pcu->si_cache);
return 0;
}
struct gprs_pcu *gprs_pcu_alloc(void *ctx)
{
struct gprs_pcu *pcu;
pcu = (struct gprs_pcu *)talloc_zero(ctx, struct gprs_pcu);
OSMO_ASSERT(pcu);
talloc_set_destructor(pcu, gprs_pcu_talloc_destructor);
pcu->vty.fc_interval = 1;
pcu->vty.max_cs_ul = MAX_GPRS_CS;
pcu->vty.max_cs_dl = MAX_GPRS_CS;
pcu->vty.max_mcs_ul = MAX_EDGE_MCS;
pcu->vty.max_mcs_dl = MAX_EDGE_MCS;
pcu->vty.force_alpha = (uint8_t)-1; /* don't force by default, use BTS SI13 provided value */
pcu->vty.dl_tbf_preemptive_retransmission = true;
/* By default resegmentation is supported in DL can also be configured
* through VTY */
pcu->vty.dl_arq_type = EGPRS_ARQ1;
pcu->vty.cs_adj_enabled = true;
pcu->vty.cs_adj_upper_limit = 33; /* Decrease CS if the error rate is above */
pcu->vty.cs_adj_lower_limit = 10; /* Increase CS if the error rate is below */
pcu->vty.cs_downgrade_threshold = 200;
/* CS-1 to CS-4 */
pcu->vty.cs_lqual_ranges[0].low = -256;
pcu->vty.cs_lqual_ranges[0].high = 6;
pcu->vty.cs_lqual_ranges[1].low = 5;
pcu->vty.cs_lqual_ranges[1].high = 8;
pcu->vty.cs_lqual_ranges[2].low = 7;
pcu->vty.cs_lqual_ranges[2].high = 13;
pcu->vty.cs_lqual_ranges[3].low = 12;
pcu->vty.cs_lqual_ranges[3].high = 256;
/* MCS-1 to MCS-9 */
/* Default thresholds are referenced from literature */
/* Fig. 2.3, Chapter 2, Optimizing Wireless Communication Systems, Springer (2009) */
pcu->vty.mcs_lqual_ranges[0].low = -256;
pcu->vty.mcs_lqual_ranges[0].high = 6;
pcu->vty.mcs_lqual_ranges[1].low = 5;
pcu->vty.mcs_lqual_ranges[1].high = 8;
pcu->vty.mcs_lqual_ranges[2].low = 7;
pcu->vty.mcs_lqual_ranges[2].high = 13;
pcu->vty.mcs_lqual_ranges[3].low = 12;
pcu->vty.mcs_lqual_ranges[3].high = 15;
pcu->vty.mcs_lqual_ranges[4].low = 14;
pcu->vty.mcs_lqual_ranges[4].high = 17;
pcu->vty.mcs_lqual_ranges[5].low = 16;
pcu->vty.mcs_lqual_ranges[5].high = 18;
pcu->vty.mcs_lqual_ranges[6].low = 17;
pcu->vty.mcs_lqual_ranges[6].high = 20;
pcu->vty.mcs_lqual_ranges[7].low = 19;
pcu->vty.mcs_lqual_ranges[7].high = 24;
pcu->vty.mcs_lqual_ranges[8].low = 23;
pcu->vty.mcs_lqual_ranges[8].high = 256;
pcu->vty.ns_dialect = GPRS_NS2_DIALECT_IPACCESS;
pcu->vty.ns_ip_dscp = -1;
pcu->vty.ns_priority = -1;
/* TODO: increase them when CRBB decoding is implemented */
pcu->vty.ws_base = 64;
pcu->vty.ws_pdch = 0;
pcu->vty.llc_codel_interval_msec = LLC_CODEL_USE_DEFAULT;
pcu->vty.llc_idle_ack_csec = 10;
Support Neighbor Address Resolution over PCUIF IPA multiplex While NACC was initially developed, it became clear there was need for a way to interact PCU<->BSC in order resolve ARFCN+BSIC into CGI-PS for later RIM usage. Hence, this resolution was first (until today) implemented using an out of bands RPC system using the CTRL interface, which required specific config to be written and matches in osmo-pcu and osmo-bsc VTY (ip+port of the CTRL interface to use). However, this has several shortcomings: * As explained above, specific configuration is required * Since recently, we do support BSC redundancy in osmo-bts. Hence the BTS may switch to a BSC other than first one. If that happened, that'd mean the CTRL interface would still point to the initially configured one, which may not be the same currently serving the PCU. During recent development of ANR related features, a similar need for PCU<->BSC was required, but this time it was decided to extend the IPA multiplex of the Abis OML connection to pass PCUIF messages, transparently forwarded to each side by the BTS. This has the advantage that connection PCU<->BTS is handled by BTS and both sides send messages transparently. Let's switch by default to using this new interface, while still maintaing the old way for a while (announcing them as deprecated) to avoid breaking existing deployments until they are upgraded to new versions of osmo-pcu and osmo-bsc. Related: SYS#4971 Change-Id: I6ad33c7ab10202840cf804dea9ba595978d0e920
1 year ago
pcu->vty.neigh_ctrl_addr = NULL; /* don't use CTRL iface for Neigh Addr Resolution */
pcu->vty.neigh_ctrl_port = OSMO_CTRL_PORT_BSC_NEIGH;
pcu->T_defs = T_defs_pcu;
osmo_tdefs_reset(pcu->T_defs);
INIT_LLIST_HEAD(&pcu->bts_list);
pcu->neigh_cache = neigh_cache_alloc(pcu, osmo_tdef_get(pcu->T_defs, PCU_TDEF_NEIGH_CACHE_ALIVE, OSMO_TDEF_S, -1));
pcu->si_cache = si_cache_alloc(pcu, osmo_tdef_get(pcu->T_defs, PCU_TDEF_SI_CACHE_ALIVE, OSMO_TDEF_S, -1));
return pcu;
}
struct gprs_rlcmac_bts *gprs_pcu_get_bts_by_nr(struct gprs_pcu *pcu, uint8_t bts_nr)
{
struct gprs_rlcmac_bts *pos;
llist_for_each_entry(pos, &pcu->bts_list, list) {
if (pos->nr == bts_nr)
return pos;
}
return NULL;
}
struct gprs_rlcmac_bts *gprs_pcu_get_bts_by_cgi_ps(struct gprs_pcu *pcu, struct osmo_cell_global_id_ps *cgi_ps)
{
struct gprs_rlcmac_bts *pos;
llist_for_each_entry(pos, &pcu->bts_list, list) {
if (osmo_cgi_ps_cmp(&pos->cgi_ps, cgi_ps) == 0)
return pos;
}
return NULL;
}
void gprs_pcu_set_initial_cs(struct gprs_pcu *pcu, uint8_t cs_dl, uint8_t cs_ul)
{
struct gprs_rlcmac_bts *bts;
the_pcu->vty.initial_cs_dl = cs_dl;
the_pcu->vty.initial_cs_ul = cs_ul;
llist_for_each_entry(bts, &pcu->bts_list, list) {
bts_recalc_initial_cs(bts);
}
}
void gprs_pcu_set_initial_mcs(struct gprs_pcu *pcu, uint8_t mcs_dl, uint8_t mcs_ul)
{
struct gprs_rlcmac_bts *bts;
the_pcu->vty.initial_mcs_dl = mcs_dl;
the_pcu->vty.initial_mcs_ul = mcs_ul;
llist_for_each_entry(bts, &pcu->bts_list, list) {
bts_recalc_initial_mcs(bts);
}
}
void gprs_pcu_set_max_cs(struct gprs_pcu *pcu, uint8_t cs_dl, uint8_t cs_ul)
{
struct gprs_rlcmac_bts *bts;
the_pcu->vty.max_cs_dl = cs_dl;
the_pcu->vty.max_cs_ul = cs_ul;
llist_for_each_entry(bts, &pcu->bts_list, list) {
bts_recalc_max_cs(bts);
}
}
void gprs_pcu_set_max_mcs(struct gprs_pcu *pcu, uint8_t mcs_dl, uint8_t mcs_ul)
{
struct gprs_rlcmac_bts *bts;
the_pcu->vty.max_mcs_dl = mcs_dl;
the_pcu->vty.max_mcs_ul = mcs_ul;
llist_for_each_entry(bts, &pcu->bts_list, list) {
bts_recalc_max_mcs(bts);
}
}