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bts-trx: Allocate struct osmo_trx_clock_state as part of bts-trx private data 

Related: OS#4215
Change-Id: I9b7ffb51423ada74b8be347c57eade08f307f88f
This commit is contained in:
Pau Espin 2019-09-27 16:44:14 +02:00 committed by pespin
parent 972c243146
commit accbf5bc73
3 changed files with 52 additions and 44 deletions
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44
src/osmo-bts-trx/l1_if.h
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@ -5,6 +5,50 @@
#include <osmo-bts/phy_link.h>
#include "trx_if.h"
/*
* TRX frame clock handling
*
* In a "normal" synchronous PHY layer, we would be polled every time
* the PHY needs data for a given frame number. However, the
* OpenBTS-inherited TRX protocol works differently: We (L1) must
* autonomously send burst data based on our own clock, and every so
* often (currently every ~ 216 frames), we get a clock indication from
* the TRX.
*
* We're using a MONOTONIC timerfd interval timer for the 4.615ms frame
* intervals, and then compute + send the 8 bursts for that frame.
*
* Upon receiving a clock indication from the TRX, we compensate
* accordingly: If we were transmitting too fast, we're delaying the
* next interval timer accordingly. If we were too slow, we immediately
* send burst data for the missing frame numbers.
*/
/*! clock state of a given TRX */
struct osmo_trx_clock_state {
/*! number of FN periods without TRX clock indication */
uint32_t fn_without_clock_ind;
struct {
/*! last FN we processed based on FN period timer */
uint32_t fn;
/*! time at which we last processed FN */
struct timespec tv;
} last_fn_timer;
struct {
/*! last FN we received a clock indication for */
uint32_t fn;
/*! time at which we received the last clock indication */
struct timespec tv;
} last_clk_ind;
/*! Osmocom FD wrapper for timerfd */
struct osmo_fd fn_timer_ofd;
};
/* gsm_bts->model_priv, specific to osmo-bts-trx */
struct bts_trx_priv {
struct osmo_trx_clock_state clk_s;
};
struct trx_config {
uint8_t trxd_hdr_ver_req; /* requested TRXD header version */
uint8_t trxd_hdr_ver_use; /* actual TRXD header version in use */

4
src/osmo-bts-trx/main.c
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@ -97,6 +97,10 @@ int bts_model_handle_options(int argc, char **argv)
int bts_model_init(struct gsm_bts *bts)
{
struct bts_trx_priv *bts_trx = talloc_zero(bts, struct bts_trx_priv);
bts_trx->clk_s.fn_timer_ofd.fd = -1;
bts->model_priv = bts_trx;
bts->variant = BTS_OSMO_TRX;
bts->support.ciphers = CIPHER_A5(1) | CIPHER_A5(2) | CIPHER_A5(3);

48
src/osmo-bts-trx/scheduler_trx.c
View File

@ -1581,48 +1581,6 @@ static int trx_sched_fn(struct gsm_bts *bts, uint32_t fn)
return 0;
}
/*
* TRX frame clock handling
*
* In a "normal" synchronous PHY layer, we would be polled every time
* the PHY needs data for a given frame number. However, the
* OpenBTS-inherited TRX protocol works differently: We (L1) must
* autonomously send burst data based on our own clock, and every so
* often (currently every ~ 216 frames), we get a clock indication from
* the TRX.
*
* We're using a MONOTONIC timerfd interval timer for the 4.615ms frame
* intervals, and then compute + send the 8 bursts for that frame.
*
* Upon receiving a clock indication from the TRX, we compensate
* accordingly: If we were transmitting too fast, we're delaying the
* next interval timer accordingly. If we were too slow, we immediately
* send burst data for the missing frame numbers.
*/
/*! clock state of a given TRX */
struct osmo_trx_clock_state {
/*! number of FN periods without TRX clock indication */
uint32_t fn_without_clock_ind;
struct {
/*! last FN we processed based on FN period timer */
uint32_t fn;
/*! time at which we last processed FN */
struct timespec tv;
} last_fn_timer;
struct {
/*! last FN we received a clock indication for */
uint32_t fn;
/*! time at which we received the last clock indication */
struct timespec tv;
} last_clk_ind;
/*! Osmocom FD wrapper for timerfd */
struct osmo_fd fn_timer_ofd;
};
/* TODO: This must go and become part of the phy_link */
static struct osmo_trx_clock_state g_clk_s = { .fn_timer_ofd.fd = -1 };
/*! duration of a GSM frame in nano-seconds. (120ms/26) */
#define FRAME_DURATION_nS 4615384
/*! duration of a GSM frame in micro-seconds (120s/26) */
@ -1666,7 +1624,8 @@ extern int quit;
static int trx_fn_timer_cb(struct osmo_fd *ofd, unsigned int what)
{
struct gsm_bts *bts = ofd->data;
struct osmo_trx_clock_state *tcs = &g_clk_s;
struct bts_trx_priv *bts_trx = (struct bts_trx_priv *)bts->model_priv;
struct osmo_trx_clock_state *tcs = &bts_trx->clk_s;
struct timespec tv_now;
uint64_t expire_count;
int64_t elapsed_us, error_us;
@ -1749,7 +1708,8 @@ static int trx_setup_clock(struct gsm_bts *bts, struct osmo_trx_clock_state *tcs
/*! called every time we receive a clock indication from TRX */
int trx_sched_clock(struct gsm_bts *bts, uint32_t fn)
{
struct osmo_trx_clock_state *tcs = &g_clk_s;
struct bts_trx_priv *bts_trx = (struct bts_trx_priv *)bts->model_priv;
struct osmo_trx_clock_state *tcs = &bts_trx->clk_s;
struct timespec tv_now;
int elapsed_fn;
int64_t elapsed_us, elapsed_us_since_clk, elapsed_fn_since_clk, error_us_since_clk;