osmo-bts/src/osmo-bts-trx/trx_if.c

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/*
* OpenBTS-style TRX interface/protocol handling
*
* This file contains the BTS-side implementation of the OpenBTS-style
* UDP TRX protocol. It manages the clock, control + burst-data UDP
* sockets and their respective protocol encoding/parsing.
*
* Copyright (C) 2013 Andreas Eversberg <jolly@eversberg.eu>
* Copyright (C) 2016 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 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 <stdio.h>
#include <stdint.h>
#include <unistd.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>
#include <netinet/in.h>
#include <osmocom/core/select.h>
#include <osmocom/core/socket.h>
#include <osmocom/core/timer.h>
#include <osmocom/core/talloc.h>
#include <osmocom/core/bits.h>
#include <osmo-bts/phy_link.h>
#include <osmo-bts/logging.h>
#include <osmo-bts/bts.h>
#include <osmo-bts/scheduler.h>
#include "l1_if.h"
#include "trx_if.h"
/* enable to print RSSI level graph */
//#define TOA_RSSI_DEBUG
int transceiver_available = 0;
int settsc_enabled = 0;
int setbsic_enabled = 0;
#define TRX_MAX_BURST_LEN 512
/*
* socket helper functions
*/
/*! convenience wrapper to open socket + fill in osmo_fd */
static int trx_udp_open(void *priv, struct osmo_fd *ofd, const char *host_local,
uint16_t port_local, const char *host_remote, uint16_t port_remote,
int (*cb)(struct osmo_fd *fd, unsigned int what))
{
int rc;
/* Init */
ofd->fd = -1;
ofd->cb = cb;
ofd->data = priv;
/* Listen / Binds + Connect */
rc = osmo_sock_init2_ofd(ofd, AF_UNSPEC, SOCK_DGRAM, IPPROTO_UDP, host_local, port_local,
host_remote, port_remote, OSMO_SOCK_F_BIND | OSMO_SOCK_F_CONNECT);
if (rc < 0)
return rc;
return 0;
}
/* close socket + unregister osmo_fd */
static void trx_udp_close(struct osmo_fd *ofd)
{
if (ofd->fd > 0) {
osmo_fd_unregister(ofd);
close(ofd->fd);
ofd->fd = -1;
}
}
/*
* TRX clock socket
*/
/* get clock from clock socket */
static int trx_clk_read_cb(struct osmo_fd *ofd, unsigned int what)
{
struct phy_link *plink = ofd->data;
struct phy_instance *pinst = phy_instance_by_num(plink, 0);
char buf[1500];
int len;
uint32_t fn;
len = recv(ofd->fd, buf, sizeof(buf) - 1, 0);
if (len <= 0)
return len;
buf[len] = '\0';
if (!!strncmp(buf, "IND CLOCK ", 10)) {
LOGP(DTRX, LOGL_NOTICE, "Unknown message on clock port: %s\n",
buf);
return 0;
}
sscanf(buf, "IND CLOCK %u", &fn);
LOGP(DTRX, LOGL_INFO, "Clock indication: fn=%u\n", fn);
if (fn >= GSM_HYPERFRAME) {
fn %= GSM_HYPERFRAME;
LOGP(DTRX, LOGL_ERROR, "Indicated clock's FN is not wrapping "
"correctly, correcting to fn=%u\n", fn);
}
/* inform core TRX clock handling code that a FN has been received */
trx_sched_clock(pinst->trx->bts, fn);
return 0;
}
/*
* TRX ctrl socket
*/
static void trx_ctrl_timer_cb(void *data);
/* send first ctrl message and start timer */
static void trx_ctrl_send(struct trx_l1h *l1h)
{
struct trx_ctrl_msg *tcm;
/* get first command */
if (llist_empty(&l1h->trx_ctrl_list))
return;
tcm = llist_entry(l1h->trx_ctrl_list.next, struct trx_ctrl_msg, list);
LOGP(DTRX, LOGL_DEBUG, "Sending control '%s' to %s\n", tcm->cmd,
phy_instance_name(l1h->phy_inst));
/* send command */
send(l1h->trx_ofd_ctrl.fd, tcm->cmd, strlen(tcm->cmd)+1, 0);
/* start timer */
l1h->trx_ctrl_timer.cb = trx_ctrl_timer_cb;
l1h->trx_ctrl_timer.data = l1h;
osmo_timer_schedule(&l1h->trx_ctrl_timer, 2, 0);
}
/* send first ctrl message and start timer */
static void trx_ctrl_timer_cb(void *data)
{
struct trx_l1h *l1h = data;
LOGP(DTRX, LOGL_NOTICE, "No response from transceiver for %s\n",
phy_instance_name(l1h->phy_inst));
trx_ctrl_send(l1h);
}
/*! Send a new TRX control command.
* \param[inout] l1h TRX Layer1 handle to which to send command
* \param[in] criticial
* \param[in] cmd zero-terminated string containing command
* \param[in] fmt Format string (+ variable list of arguments)
* \returns 0 on success; negative on error
*
* The new ocommand will be added to the end of the control command
* queue.
*/
static int trx_ctrl_cmd(struct trx_l1h *l1h, int critical, const char *cmd,
const char *fmt, ...)
{
struct trx_ctrl_msg *tcm;
va_list ap;
int l, pending = 0;
if (!transceiver_available &&
!(!strcmp(cmd, "POWEROFF") || !strcmp(cmd, "POWERON"))) {
LOGP(DTRX, LOGL_ERROR, "CTRL %s ignored: No clock from "
"transceiver, please fix!\n", cmd);
return -EIO;
}
if (!llist_empty(&l1h->trx_ctrl_list))
pending = 1;
/* create message */
tcm = talloc_zero(tall_bts_ctx, struct trx_ctrl_msg);
if (!tcm)
return -ENOMEM;
if (fmt && fmt[0]) {
l = snprintf(tcm->cmd, sizeof(tcm->cmd)-1, "CMD %s ", cmd);
va_start(ap, fmt);
vsnprintf(tcm->cmd + l, sizeof(tcm->cmd) - l - 1, fmt, ap);
va_end(ap);
} else
snprintf(tcm->cmd, sizeof(tcm->cmd)-1, "CMD %s", cmd);
tcm->cmd_len = strlen(cmd);
tcm->critical = critical;
llist_add_tail(&tcm->list, &l1h->trx_ctrl_list);
LOGP(DTRX, LOGL_INFO, "Enqueuing TRX control command '%s'\n", tcm->cmd);
/* send message, if we didn't already have pending messages */
if (!pending)
trx_ctrl_send(l1h);
return 0;
}
/*! Send "POWEROFF" command to TRX */
int trx_if_cmd_poweroff(struct trx_l1h *l1h)
{
struct phy_instance *pinst = l1h->phy_inst;
if (pinst->num == 0)
return trx_ctrl_cmd(l1h, 1, "POWEROFF", "");
else
return 0;
}
/*! Send "POWERON" command to TRX */
int trx_if_cmd_poweron(struct trx_l1h *l1h)
{
struct phy_instance *pinst = l1h->phy_inst;
if (pinst->num == 0)
return trx_ctrl_cmd(l1h, 1, "POWERON", "");
else
return 0;
}
/*! Send "SETTSC" command to TRX */
int trx_if_cmd_settsc(struct trx_l1h *l1h, uint8_t tsc)
{
if (!settsc_enabled)
return 0;
/* if TSC is enabled only, the positive response is mandatory */
return trx_ctrl_cmd(l1h, (setbsic_enabled) ? 0 : 1, "SETTSC", "%d",
tsc);
}
/*! Send "SETBSIC" command to TRX */
int trx_if_cmd_setbsic(struct trx_l1h *l1h, uint8_t bsic)
{
if (!setbsic_enabled)
return 0;
/* if BSIC is enabled only, the positive response is mandatory */
return trx_ctrl_cmd(l1h, (settsc_enabled) ? 0 : 1, "SETBSIC", "%d",
bsic);
}
/*! Send "SETRXGAIN" command to TRX */
int trx_if_cmd_setrxgain(struct trx_l1h *l1h, int db)
{
return trx_ctrl_cmd(l1h, 0, "SETRXGAIN", "%d", db);
}
/*! Send "SETPOWER" command to TRX */
int trx_if_cmd_setpower(struct trx_l1h *l1h, int db)
{
return trx_ctrl_cmd(l1h, 0, "SETPOWER", "%d", db);
}
/*! Send "SETMAXDLY" command to TRX, i.e. maximum delay for RACH bursts */
int trx_if_cmd_setmaxdly(struct trx_l1h *l1h, int dly)
{
return trx_ctrl_cmd(l1h, 0, "SETMAXDLY", "%d", dly);
}
/*! Send "SETMAXDLYNB" command to TRX, i.e. maximum delay for normal bursts */
int trx_if_cmd_setmaxdlynb(struct trx_l1h *l1h, int dly)
{
return trx_ctrl_cmd(l1h, 0, "SETMAXDLYNB", "%d", dly);
}
/*! Send "SETSLOT" command to TRX: Configure Channel Combination for TS */
int trx_if_cmd_setslot(struct trx_l1h *l1h, uint8_t tn, uint8_t type)
{
return trx_ctrl_cmd(l1h, 1, "SETSLOT", "%d %d", tn, type);
}
/*! Send "RXTUNE" command to TRX: Tune Receiver to given ARFCN */
int trx_if_cmd_rxtune(struct trx_l1h *l1h, uint16_t arfcn)
{
struct phy_instance *pinst = l1h->phy_inst;
uint16_t freq10;
if (pinst->trx->bts->band == GSM_BAND_1900)
arfcn |= ARFCN_PCS;
freq10 = gsm_arfcn2freq10(arfcn, 1); /* RX = uplink */
if (freq10 == 0xffff) {
LOGP(DTRX, LOGL_ERROR, "Arfcn %d not defined.\n",
arfcn & ~ARFCN_FLAG_MASK);
return -ENOTSUP;
}
return trx_ctrl_cmd(l1h, 1, "RXTUNE", "%d", freq10 * 100);
}
/*! Send "TXTUNE" command to TRX: Tune Transmitter to given ARFCN */
int trx_if_cmd_txtune(struct trx_l1h *l1h, uint16_t arfcn)
{
struct phy_instance *pinst = l1h->phy_inst;
uint16_t freq10;
if (pinst->trx->bts->band == GSM_BAND_1900)
arfcn |= ARFCN_PCS;
freq10 = gsm_arfcn2freq10(arfcn, 0); /* TX = downlink */
if (freq10 == 0xffff) {
LOGP(DTRX, LOGL_ERROR, "Arfcn %d not defined.\n",
arfcn & ~ARFCN_FLAG_MASK);
return -ENOTSUP;
}
return trx_ctrl_cmd(l1h, 1, "TXTUNE", "%d", freq10 * 100);
}
/*! Send "HANDOVER" command to TRX: Enable handover RACH Detection on timeslot/sub-slot */
2013-06-12 07:12:04 +00:00
int trx_if_cmd_handover(struct trx_l1h *l1h, uint8_t tn, uint8_t ss)
{
return trx_ctrl_cmd(l1h, 1, "HANDOVER", "%d %d", tn, ss);
}
/*! Send "NOHANDOVER" command to TRX: Disable handover RACH Detection on timeslot/sub-slot */
2013-06-12 07:12:04 +00:00
int trx_if_cmd_nohandover(struct trx_l1h *l1h, uint8_t tn, uint8_t ss)
{
return trx_ctrl_cmd(l1h, 1, "NOHANDOVER", "%d %d", tn, ss);
}
/*! Get + parse response from TRX ctrl socket */
static int trx_ctrl_read_cb(struct osmo_fd *ofd, unsigned int what)
{
struct trx_l1h *l1h = ofd->data;
struct phy_instance *pinst = l1h->phy_inst;
char buf[1500];
int len, resp;
len = recv(ofd->fd, buf, sizeof(buf) - 1, 0);
if (len <= 0)
return len;
buf[len] = '\0';
if (!strncmp(buf, "RSP ", 4)) {
struct trx_ctrl_msg *tcm;
char *p;
int rsp_len = 0;
/* calculate the length of response item */
p = strchr(buf + 4, ' ');
if (p)
rsp_len = p - buf - 4;
else
rsp_len = strlen(buf) - 4;
LOGP(DTRX, LOGL_INFO, "Response message: '%s'\n", buf);
/* abort timer and send next message, if any */
if (osmo_timer_pending(&l1h->trx_ctrl_timer))
osmo_timer_del(&l1h->trx_ctrl_timer);
/* get command for response message */
if (llist_empty(&l1h->trx_ctrl_list)) {
LOGP(DTRX, LOGL_NOTICE, "Response message without "
"command\n");
return -EINVAL;
}
tcm = llist_entry(l1h->trx_ctrl_list.next, struct trx_ctrl_msg,
list);
/* check if response matches command */
if (rsp_len != tcm->cmd_len) {
notmatch:
LOGP(DTRX, (tcm->critical) ? LOGL_FATAL : LOGL_NOTICE,
"Response message '%s' does not match command "
"message '%s'\n", buf, tcm->cmd);
goto rsp_error;
}
if (!!strncmp(buf + 4, tcm->cmd + 4, rsp_len))
goto notmatch;
/* check for response code */
sscanf(p + 1, "%d", &resp);
if (resp) {
LOGP(DTRX, (tcm->critical) ? LOGL_FATAL : LOGL_NOTICE,
"transceiver (%s) rejected TRX command "
"with response: '%s'\n",
phy_instance_name(pinst), buf);
rsp_error:
if (tcm->critical) {
bts_shutdown(pinst->trx->bts, "TRX-CTRL-MSG: CRITICAL");
/* keep tcm list, so process is stopped */
return -EIO;
}
}
/* remove command from list */
llist_del(&tcm->list);
talloc_free(tcm);
trx_ctrl_send(l1h);
} else
LOGP(DTRX, LOGL_NOTICE, "Unknown message on ctrl port: %s\n",
buf);
return 0;
}
/*
* TRX burst data socket
*/
static int trx_data_read_cb(struct osmo_fd *ofd, unsigned int what)
{
struct trx_l1h *l1h = ofd->data;
uint8_t buf[TRX_MAX_BURST_LEN];
int len;
uint8_t tn;
int8_t rssi;
float toa = 0.0;
uint32_t fn;
sbit_t bits[EGPRS_BURST_LEN];
int i, burst_len = GSM_BURST_LEN;
len = recv(ofd->fd, buf, sizeof(buf), 0);
if (len <= 0) {
return len;
} else if (len == EGPRS_BURST_LEN + 10) {
burst_len = EGPRS_BURST_LEN;
} else if (len != GSM_BURST_LEN + 10) {
LOGP(DTRX, LOGL_NOTICE, "Got data message with invalid lenght "
"'%d'\n", len);
return -EINVAL;
}
tn = buf[0];
fn = (buf[1] << 24) | (buf[2] << 16) | (buf[3] << 8) | buf[4];
rssi = -(int8_t)buf[5];
toa = ((int16_t)(buf[6] << 8) | buf[7]) / 256.0F;
/* copy and convert bits {254..0} to sbits {-127..127} */
for (i = 0; i < burst_len; i++) {
if (buf[8 + i] == 255)
bits[i] = -127;
else
bits[i] = 127 - buf[8 + i];
}
if (tn >= 8) {
LOGP(DTRX, LOGL_ERROR, "Illegal TS %d\n", tn);
return -EINVAL;
}
if (fn >= GSM_HYPERFRAME) {
LOGP(DTRX, LOGL_ERROR, "Illegal FN %u\n", fn);
return -EINVAL;
}
LOGP(DTRX, LOGL_DEBUG, "RX burst tn=%u fn=%u rssi=%d toa=%.2f\n",
tn, fn, rssi, toa);
#ifdef TOA_RSSI_DEBUG
char deb[128];
sprintf(deb, "| 0 "
" | rssi=%4d toa=%4.2f fn=%u", rssi, toa, fn);
deb[1 + (128 + rssi) / 4] = '*';
fprintf(stderr, "%s\n", deb);
#endif
/* feed received burst into scheduler code */
trx_sched_ul_burst(&l1h->l1s, tn, fn, bits, burst_len, rssi, toa);
return 0;
}
/*! Send burst data for given FN/timeslot to TRX
* \param[inout] l1h TRX Layer1 handle referring to TX
* \param[in] tn Timeslot Number (0..7)
* \param[in] fn GSM Frame Number
* \param[in] pwr Transmit Power to use
* \param[in] bits Unpacked bits to be transmitted
* \param[in] nbits Number of \a bits
* \returns 0 on success; negative on error */
int trx_if_data(struct trx_l1h *l1h, uint8_t tn, uint32_t fn, uint8_t pwr,
const ubit_t *bits, uint16_t nbits)
{
uint8_t buf[TRX_MAX_BURST_LEN];
if ((nbits != GSM_BURST_LEN) && (nbits != EGPRS_BURST_LEN)) {
LOGP(DTRX, LOGL_ERROR, "Tx burst length %u invalid\n", nbits);
return -1;
}
LOGP(DTRX, LOGL_DEBUG, "TX burst tn=%u fn=%u pwr=%u\n", tn, fn, pwr);
buf[0] = tn;
buf[1] = (fn >> 24) & 0xff;
buf[2] = (fn >> 16) & 0xff;
buf[3] = (fn >> 8) & 0xff;
buf[4] = (fn >> 0) & 0xff;
buf[5] = pwr;
/* copy ubits {0,1} */
memcpy(buf + 6, bits, nbits);
/* we must be sure that we have clock, and we have sent all control
* data */
if (transceiver_available && llist_empty(&l1h->trx_ctrl_list)) {
send(l1h->trx_ofd_data.fd, buf, nbits + 6, 0);
} else
LOGP(DTRX, LOGL_DEBUG, "Ignoring TX data, transceiver "
"offline.\n");
return 0;
}
/*
* open/close
*/
/*! open the PHY link using TRX protocol */
int bts_model_phy_link_open(struct phy_link *plink)
{
struct phy_instance *pinst;
int rc;
phy_link_state_set(plink, PHY_LINK_CONNECTING);
/* open the shared/common clock socket */
rc = trx_udp_open(plink, &plink->u.osmotrx.trx_ofd_clk,
plink->u.osmotrx.local_ip,
plink->u.osmotrx.base_port_local,
plink->u.osmotrx.remote_ip,
plink->u.osmotrx.base_port_remote,
trx_clk_read_cb);
if (rc < 0) {
phy_link_state_set(plink, PHY_LINK_SHUTDOWN);
return -1;
}
/* open the individual instances with their ctrl+data sockets */
llist_for_each_entry(pinst, &plink->instances, list) {
pinst->u.osmotrx.hdl = l1if_open(pinst);
if (!pinst->u.osmotrx.hdl)
goto cleanup;
}
/* FIXME: is there better way to check/report TRX availability? */
transceiver_available = 1;
phy_link_state_set(plink, PHY_LINK_CONNECTED);
return 0;
cleanup:
phy_link_state_set(plink, PHY_LINK_SHUTDOWN);
llist_for_each_entry(pinst, &plink->instances, list) {
if (pinst->u.osmotrx.hdl) {
trx_if_close(pinst->u.osmotrx.hdl);
pinst->u.osmotrx.hdl = NULL;
}
}
trx_udp_close(&plink->u.osmotrx.trx_ofd_clk);
return -1;
}
/*! compute UDP port number used for TRX protocol */
static uint16_t compute_port(struct phy_instance *pinst, int remote, int is_data)
{
struct phy_link *plink = pinst->phy_link;
uint16_t inc = 1;
if (is_data)
inc = 2;
if (remote)
return plink->u.osmotrx.base_port_remote + (pinst->num << 1) + inc;
else
return plink->u.osmotrx.base_port_local + (pinst->num << 1) + inc;
}
/*! open a TRX interface. creates contro + data sockets */
int trx_if_open(struct trx_l1h *l1h)
{
struct phy_instance *pinst = l1h->phy_inst;
struct phy_link *plink = pinst->phy_link;
int rc;
LOGP(DTRX, LOGL_NOTICE, "Open transceiver for %s\n",
phy_instance_name(pinst));
/* initialize ctrl queue */
INIT_LLIST_HEAD(&l1h->trx_ctrl_list);
/* open sockets */
rc = trx_udp_open(l1h, &l1h->trx_ofd_ctrl,
plink->u.osmotrx.local_ip,
compute_port(pinst, 0, 0),
plink->u.osmotrx.remote_ip,
compute_port(pinst, 1, 0), trx_ctrl_read_cb);
if (rc < 0)
goto err;
rc = trx_udp_open(l1h, &l1h->trx_ofd_data,
plink->u.osmotrx.local_ip,
compute_port(pinst, 0, 1),
plink->u.osmotrx.remote_ip,
compute_port(pinst, 1, 1), trx_data_read_cb);
if (rc < 0)
goto err;
/* enable all slots */
l1h->config.slotmask = 0xff;
/* FIXME: why was this only for TRX0 ? */
//if (l1h->trx->nr == 0)
trx_if_cmd_poweroff(l1h);
return 0;
err:
trx_if_close(l1h);
return rc;
}
/*! flush (delete) all pending control messages */
void trx_if_flush(struct trx_l1h *l1h)
{
struct trx_ctrl_msg *tcm;
/* free ctrl message list */
while (!llist_empty(&l1h->trx_ctrl_list)) {
tcm = llist_entry(l1h->trx_ctrl_list.next, struct trx_ctrl_msg,
list);
llist_del(&tcm->list);
talloc_free(tcm);
}
}
/*! close the TRX for given handle (data + control socket) */
void trx_if_close(struct trx_l1h *l1h)
{
struct phy_instance *pinst = l1h->phy_inst;
LOGP(DTRX, LOGL_NOTICE, "Close transceiver for %s\n",
phy_instance_name(pinst));
trx_if_flush(l1h);
/* close sockets */
trx_udp_close(&l1h->trx_ofd_ctrl);
trx_udp_close(&l1h->trx_ofd_data);
}
/*! determine if the TRX for given handle is powered up */
int trx_if_powered(struct trx_l1h *l1h)
{
return l1h->config.poweron;
}