diff options
author | Vadim Yanitskiy <axilirator@gmail.com> | 2018-09-12 17:54:24 +0700 |
---|---|---|
committer | Vadim Yanitskiy <axilirator@gmail.com> | 2018-09-16 01:51:15 +0700 |
commit | 96419494d37c3879c375c7248fbb82647a9ce75b (patch) | |
tree | d24288a58f4e5134891197ebe7ada4822429bdc1 | |
parent | 60da22a67b228b9f07a2765ae25acdc08d2d6747 (diff) |
trxcon/scheduler: introduce TDMA frame math helpers
The 'normal' math operations, such as addition and substraction,
are not applicable for TDMA frame numbers because they may result
in out-of-range values.
Having TDMA frame math helpers in a single place would allow
one to avoid possible out-of-range result mistakes.
Change-Id: Ibb66ba846cc3d6c2eaa88414569e5f3751128047
-rw-r--r-- | src/host/trxcon/sched_clck.c | 9 | ||||
-rw-r--r-- | src/host/trxcon/sched_trx.c | 11 | ||||
-rw-r--r-- | src/host/trxcon/scheduler.h | 8 |
3 files changed, 16 insertions, 12 deletions
diff --git a/src/host/trxcon/sched_clck.c b/src/host/trxcon/sched_clck.c index dab95789..d4054c99 100644 --- a/src/host/trxcon/sched_clck.c +++ b/src/host/trxcon/sched_clck.c @@ -83,8 +83,7 @@ static void sched_clck_tick(void *data) timespecadd(tv_clock, &frame_duration, tv_clock); elapsed_us -= FRAME_DURATION_uS; - sched->fn_counter_proc = (sched->fn_counter_proc + 1) - % GSM_HYPERFRAME; + sched->fn_counter_proc = TDMA_FN_INC(sched->fn_counter_proc); /* Call frame callback */ if (sched->clock_cb) @@ -142,8 +141,7 @@ int sched_clck_handle(struct trx_sched *sched, uint32_t fn) /* Calculate elapsed time / frames since last processed fn */ timespecsub(&tv_now, tv_clock, &elapsed); elapsed_us = (elapsed.tv_sec * 1000000) + (elapsed.tv_nsec / 1000); - elapsed_fn = (fn + GSM_HYPERFRAME - sched->fn_counter_proc) - % GSM_HYPERFRAME; + elapsed_fn = TDMA_FN_SUB(fn, sched->fn_counter_proc); if (elapsed_fn >= 135774) elapsed_fn -= GSM_HYPERFRAME; @@ -181,8 +179,7 @@ int sched_clck_handle(struct trx_sched *sched, uint32_t fn) /* Transmit what we still need to transmit */ while (fn != sched->fn_counter_proc) { - sched->fn_counter_proc = (sched->fn_counter_proc + 1) - % GSM_HYPERFRAME; + sched->fn_counter_proc = TDMA_FN_INC(sched->fn_counter_proc); /* Call frame callback */ if (sched->clock_cb) diff --git a/src/host/trxcon/sched_trx.c b/src/host/trxcon/sched_trx.c index 8bd3c722..e20da39f 100644 --- a/src/host/trxcon/sched_trx.c +++ b/src/host/trxcon/sched_trx.c @@ -65,8 +65,8 @@ static void sched_frame_clck_cb(struct trx_sched *sched) * Advance frame number, giving the transceiver more * time until a burst must be transmitted... */ - fn = (sched->fn_counter_proc + sched->fn_counter_advance) - % GSM_HYPERFRAME; + fn = TDMA_FN_SUM(sched->fn_counter_proc, + sched->fn_counter_advance); /* Get frame from multiframe */ offset = fn % ts->mf_layout->period; @@ -608,15 +608,14 @@ int sched_trx_handle_rx_burst(struct trx_instance *trx, uint8_t tn, } /* Calculate how many frames have been elapsed */ - elapsed = (burst_fn + GSM_HYPERFRAME - ts->mf_last_fn); - elapsed %= GSM_HYPERFRAME; + elapsed = TDMA_FN_SUB(burst_fn, ts->mf_last_fn); /** * If not too many frames have been elapsed, * start counting from last fn + 1 */ if (elapsed < 10) - fn = (ts->mf_last_fn + 1) % GSM_HYPERFRAME; + fn = TDMA_FN_INC(ts->mf_last_fn); else fn = burst_fn; @@ -658,7 +657,7 @@ next_frame: if (fn == burst_fn) break; - fn = (fn + 1) % GSM_HYPERFRAME; + fn = TDMA_FN_INC(fn); } /* Set last processed frame number */ diff --git a/src/host/trxcon/scheduler.h b/src/host/trxcon/scheduler.h index ddb863f2..fccf7d23 100644 --- a/src/host/trxcon/scheduler.h +++ b/src/host/trxcon/scheduler.h @@ -10,6 +10,14 @@ #define GSM_SUPERFRAME (26 * 51) #define GSM_HYPERFRAME (2048 * GSM_SUPERFRAME) +/* TDMA frame number arithmetics */ +#define TDMA_FN_SUM(a, b) \ + ((a + b) % GSM_HYPERFRAME) +#define TDMA_FN_SUB(a, b) \ + ((a + GSM_HYPERFRAME - b) % GSM_HYPERFRAME) +#define TDMA_FN_INC(fn) \ + TDMA_FN_SUM(fn, 1) + enum tdma_sched_clck_state { SCH_CLCK_STATE_WAIT, SCH_CLCK_STATE_OK, |