diff options
author | Harald Welte <laforge@gnumonks.org> | 2010-04-09 21:32:56 +0200 |
---|---|---|
committer | Harald Welte <laforge@gnumonks.org> | 2010-04-09 21:32:56 +0200 |
commit | 5f751d3db87eda867a9bf6f1758c29b7325b8dd1 (patch) | |
tree | a2bd55e1d4b6974fb4562b5d7678016e6b75c783 /src/target/firmware/layer1/sync.c | |
parent | a955cfd4e26b3dd210cf9c6bd09b74329109c382 (diff) |
layer1: move FB and SB detection into prim_fbsb.c
Diffstat (limited to 'src/target/firmware/layer1/sync.c')
-rw-r--r-- | src/target/firmware/layer1/sync.c | 425 |
1 files changed, 5 insertions, 420 deletions
diff --git a/src/target/firmware/layer1/sync.c b/src/target/firmware/layer1/sync.c index 1945dc3b..9bdaba5e 100644 --- a/src/target/firmware/layer1/sync.c +++ b/src/target/firmware/layer1/sync.c @@ -72,7 +72,7 @@ void l1s_set_handler(l1s_cb_t cb) #define GSM_MAX_FN (26*51*2048) -static void l1s_time_inc(struct gsm_time *time, uint32_t delta_fn) +void l1s_time_inc(struct gsm_time *time, uint32_t delta_fn) { ADD_MODULO(time->fn, delta_fn, GSM_MAX_FN); @@ -92,35 +92,11 @@ static void l1s_time_inc(struct gsm_time *time, uint32_t delta_fn) gsm_fn2gsmtime(time, time->fn); } -static void l1s_time_dump(const struct gsm_time *time) +void l1s_time_dump(const struct gsm_time *time) { printf("fn=%u(%u/%2u/%2u)", time->fn, time->t1, time->t2, time->t3); } -/* determine the GSM time and BSIC from a Sync Burst */ -static uint8_t l1s_decode_sb(struct gsm_time *time, uint32_t sb) -{ - uint8_t bsic = (sb >> 2) & 0x3f; - uint8_t t3p; - - memset(time, 0, sizeof(*time)); - - /* TS 05.02 Chapter 3.3.2.2.1 SCH Frame Numbers */ - time->t1 = ((sb >> 23) & 1) | ((sb >> 7) & 0x1fe) | ((sb << 9) & 0x600); - time->t2 = (sb >> 18) & 0x1f; - t3p = ((sb >> 24) & 1) | ((sb >> 15) & 6); - time->t3 = t3p*10 + 1; - - /* TS 05.02 Chapter 4.3.3 TDMA frame number */ - time->fn = gsm_gsmtime2fn(time); - - time->tc = (time->fn / 51) % 8; - - return bsic; -} - -extern uint16_t rf_arfcn; // TODO - /* clip a signed 16bit value at a certain limit */ int16_t clip_int16(int16_t angle, int16_t clip_at) { @@ -147,14 +123,8 @@ uint16_t l1s_snr_fract(uint16_t snr) #define AFC_MAX_ANGLE 328 /* 0.01 radian in fx1.15 */ -#define BITS_PER_TDMA 1250 -#define QBITS_PER_TDMA (BITS_PER_TDMA * 4) /* 5000 */ -#define TPU_RANGE QBITS_PER_TDMA -#define SWITCH_TIME (TPU_RANGE-10) - - /* synchronize the L1S to a new timebase (typically a new cell */ -static void synchronize_tdma(struct l1_cell_info *cinfo) +void synchronize_tdma(struct l1_cell_info *cinfo) { int32_t fn_offset; uint32_t tpu_shift = cinfo->time_alignment; @@ -199,7 +169,7 @@ static void synchronize_tdma(struct l1_cell_info *cinfo) cinfo->time_alignment = 0; } -static void l1s_reset_hw(void) +void l1s_reset_hw(void) { dsp_api.w_page = 0; dsp_api.r_page = 0; @@ -218,82 +188,7 @@ static void l1s_reset_hw(void) tpu_end_scenario(); } -struct mon_state { - uint32_t fnr_report; /* frame number when DSP reported it */ - int attempt; /* which attempt was this ? */ - - int16_t toa; - uint16_t pm; - uint16_t angle; - uint16_t snr; - - /* computed values */ - int16_t freq_diff; -}; - -static void dump_mon_state(struct mon_state *fb) -{ -#if 0 - printf("(%u:%u): TOA=%5u, Power=%4ddBm, Angle=%5dHz, " - "SNR=%04x(%d.%u) OFFSET=%u SYNCHRO=%u\n", - fb->fnr_report, fb->attempt, fb->toa, - agc_inp_dbm8_by_pm(fb->pm)/8, ANGLE_TO_FREQ(fb->angle), - fb->snr, l1s_snr_int(fb->snr), l1s_snr_fract(fb->snr), - tpu_get_offset(), tpu_get_synchro()); -#else - printf("(%u:%u): TOA=%5u, Power=%4ddBm, Angle=%5dHz ", - fb->fnr_report, fb->attempt, fb->toa, - agc_inp_dbm8_by_pm(fb->pm)/8, ANGLE_TO_FREQ(fb->angle)); -#endif -} - -static struct mon_state _last_fb, *last_fb = &_last_fb; - -static int read_fb_result(struct mon_state *st, int attempt) -{ - st->toa = dsp_api.ndb->a_sync_demod[D_TOA]; - st->pm = dsp_api.ndb->a_sync_demod[D_PM]>>3; - st->angle = dsp_api.ndb->a_sync_demod[D_ANGLE]; - st->snr = dsp_api.ndb->a_sync_demod[D_SNR]; - - //last_fb->angle = clip_int16(last_fb->angle, AFC_MAX_ANGLE); - st->freq_diff = ANGLE_TO_FREQ(last_fb->angle); - st->fnr_report = l1s.current_time.fn; - st->attempt = attempt; - - dump_mon_state(st); - - dsp_api.ndb->d_fb_det = 0; - dsp_api.ndb->a_sync_demod[D_TOA] = 0; /* TSM30 does it (really needed ?) */ - - /* Update AFC with current frequency offset */ - afc_correct(st->freq_diff, rf_arfcn); - - //tpu_dsp_frameirq_enable(); - return 1; -} - -static void read_sb_result(struct mon_state *st, int attempt) -{ - st->toa = dsp_api.db_r->a_serv_demod[D_TOA]; - st->pm = dsp_api.db_r->a_serv_demod[D_PM]>>3; - st->angle = dsp_api.db_r->a_serv_demod[D_ANGLE]; - st->snr = dsp_api.db_r->a_serv_demod[D_SNR]; - - st->freq_diff = ANGLE_TO_FREQ(st->angle); - st->fnr_report = l1s.current_time.fn; - st->attempt = attempt; - - dump_mon_state(st); - - if (st->snr > AFC_SNR_THRESHOLD) - afc_input(st->freq_diff, rf_arfcn, 1); - else - afc_input(st->freq_diff, rf_arfcn, 0); - - dsp_api.r_page_used = 1; -} - +/* Timer for detecting lost IRQ */ #define TIMER_TICKS_PER_TDMA 1875 static int last_timestamp; @@ -409,316 +304,6 @@ void l1s_dsp_abort(void) tdma_schedule(0, &l1s_abort_cmd, 0, 0, 0); } -/* FCCH Burst *****************************************************************/ - -/* scheduler callback to issue a FB detection task to the DSP */ -static int l1s_fbdet_cmd(__unused uint8_t p1, __unused uint8_t fb_mode, - __unused uint16_t p3) -{ - if (fb_mode == 0) { - putchart('F'); - } else { - putchart('V'); - } - - /* Program DSP */ - dsp_api.db_w->d_task_md = FB_DSP_TASK; /* maybe with I/Q swap? */ - dsp_api.ndb->d_fb_mode = fb_mode; - dsp_end_scenario(); - - /* Program TPU */ - l1s_rx_win_ctrl(rf_arfcn, L1_RXWIN_FB); - tpu_end_scenario(); - - return 0; -} - - -/* scheduler callback to check for a FB detection response */ -static int l1s_fbdet_resp(__unused uint8_t p1, uint8_t attempt, - __unused uint16_t p3) -{ - int ntdma, qbits, fn_offset; - - putchart('f'); - - if (!dsp_api.ndb->d_fb_det) { - /* we did not detect a FB, fall back to mode 0! */ - if (attempt == 12) { - /* If we don't reset here, we get DSP DMA errors */ - tdma_sched_reset(); - - /* if we are already synchronized initially, - * code below has set l1s.fb.mode to 1 and - * we switch to the more narrow mode 1 */ - l1s_fb_test(1, l1s.fb.mode); - } - return 0; - } - - printf("FB%u ", dsp_api.ndb->d_fb_mode); - read_fb_result(last_fb, attempt); - - /* FIXME: where did this magic 23 come from? */ - last_fb->toa -= 23; - - if (last_fb->toa < 0) { - qbits = (last_fb->toa + BITS_PER_TDMA) * 4; - ntdma = -1; - } else { - ntdma = (last_fb->toa) / BITS_PER_TDMA; - qbits = (last_fb->toa - ntdma * BITS_PER_TDMA) * 4; - } - - { - fn_offset = l1s.current_time.fn - attempt + ntdma; - int fnr_delta = last_fb->fnr_report - attempt; - int bits_delta = fnr_delta * BITS_PER_TDMA; - - struct l1_cell_info *cinfo = &l1s.serving_cell; - - cinfo->fn_offset = fnr_delta; - cinfo->time_alignment = qbits; - cinfo->arfcn = rf_arfcn; - - if (last_fb->toa > bits_delta) - printf("=> DSP reports FB in bit that is %d bits in " - "the future?!?\n", last_fb->toa - bits_delta); - else { - int fb_fnr = (last_fb->fnr_report - last_fb->attempt) - + last_fb->toa/BITS_PER_TDMA; - printf("=>FB @ FNR %u fn_offset=%d qbits=%u\n", - fb_fnr, fn_offset, qbits); - } - } - - /* We found a frequency burst, reset everything and start next task */ - l1s_reset_hw(); - tdma_sched_reset(); - - if (dsp_api.frame_ctr > 500 && l1s.fb.mode == 0) { - /* We've done more than 500 rounds of FB detection, so - * the AGC should be synchronized and we switch to the - * more narrow FB detection mode 1 */ - l1s.fb.mode = 1; - /* Don't synchronize_tdma() yet, it does probably not work - * reliable due to the TPU reset) */ - } - -#if 1 - /* restart a SB or new FB detection task */ - if (dsp_api.frame_ctr > 1000 && l1s.fb.mode == 1 && - abs(last_fb->freq_diff) < 1000) { - int delay; - - /* synchronize before reading SB */ - synchronize_tdma(&l1s.serving_cell); - - delay = fn_offset + 11 - l1s.current_time.fn - 1; - dsp_api.ndb->d_fb_det = 0; - dsp_api.ndb->a_sync_demod[D_TOA] = 0; /* TSM30 does it (really needed ?) */ - l1s.fb.mode = 0; - l1s_sb_test(delay); - } else -#endif - { - /* If we don't reset here, we get DSP DMA errors */ - tdma_sched_reset(); - /* use FB_MODE_1 if we are within certain limits */ - if (abs(last_fb->freq_diff < 2000)) - l1s_fb_test(fn_offset + 10 - l1s.current_time.fn - 1, 1); - else - l1s_fb_test(fn_offset + 10 - l1s.current_time.fn - 1, 0); - } - - return 0; -} - -/* we don't really use this because we need to configure the fb_mode! */ -static const struct tdma_sched_item fb_sched_set[] = { - SCHED_ITEM(l1s_fbdet_cmd, 0, 0), SCHED_END_FRAME(), - SCHED_END_FRAME(), - SCHED_ITEM(l1s_fbdet_resp, 0, 1), SCHED_END_FRAME(), - SCHED_ITEM(l1s_fbdet_resp, 0, 2), SCHED_END_FRAME(), - SCHED_ITEM(l1s_fbdet_resp, 0, 3), SCHED_END_FRAME(), - SCHED_ITEM(l1s_fbdet_resp, 0, 4), SCHED_END_FRAME(), - SCHED_ITEM(l1s_fbdet_resp, 0, 5), SCHED_END_FRAME(), - SCHED_ITEM(l1s_fbdet_resp, 0, 6), SCHED_END_FRAME(), - SCHED_ITEM(l1s_fbdet_resp, 0, 7), SCHED_END_FRAME(), - SCHED_ITEM(l1s_fbdet_resp, 0, 8), SCHED_END_FRAME(), - SCHED_ITEM(l1s_fbdet_resp, 0, 9), SCHED_END_FRAME(), - SCHED_ITEM(l1s_fbdet_resp, 0, 10), SCHED_END_FRAME(), - SCHED_ITEM(l1s_fbdet_resp, 0, 11), SCHED_END_FRAME(), - SCHED_ITEM(l1s_fbdet_resp, 0, 12), SCHED_END_FRAME(), - SCHED_END_SET() -}; - -void l1s_fb_test(uint8_t base_fn, uint8_t fb_mode) -{ -#if 1 - int i; - /* schedule the FB detection command */ - tdma_schedule(base_fn, &l1s_fbdet_cmd, 0, fb_mode, 0); - - /* schedule 12 attempts to read the result */ - for (i = 1; i <= 12; i++) { - uint8_t fn = base_fn + 1 + i; - tdma_schedule(fn, &l1s_fbdet_resp, 0, i, 0); - } -#else - /* use the new scheduler 'set' and simply schedule the whole set */ - /* WARNING: we cannot set FB_MODE_1 this way !!! */ - tdma_schedule_set(base_fn, fb_sched_set, 0); -#endif -} - -/* SCH Burst Detection ********************************************************/ - -/* Note: When we get the SB response, it is 2 TDMA frames after the SB - * actually happened, as it is a "C W W R" task */ -#define SB2_LATENCY 2 - -static int l1s_sbdet_resp(__unused uint8_t p1, uint8_t attempt, - __unused uint16_t p3) -{ - uint32_t sb; - uint8_t bsic; - static struct gsm_time sb_time; - int qbits, fn_offset; - struct l1_cell_info *cinfo = &l1s.serving_cell; - int fnr_delta, bits_delta; - struct l1ctl_sync_new_ccch_resp *l1; - struct msgb *msg; - - putchart('s'); - - if (dsp_api.db_r->a_sch[0] & (1<<B_SCH_CRC)) { - /* after 2nd attempt, restart */ - if (attempt == 2) - l1s_sb_test(2); - - /* mark READ page as being used */ - dsp_api.r_page_used = 1; - - return 0; - } - - l1s.sb.count++; - - printf("SB%d ", attempt); - read_sb_result(last_fb, dsp_api.frame_ctr); - - sb = dsp_api.db_r->a_sch[3] | dsp_api.db_r->a_sch[4] << 16; - bsic = l1s_decode_sb(&sb_time, sb); - printf("=> SB 0x%08x: BSIC=%u ", sb, bsic); - l1s_time_dump(&sb_time); - - l1s.serving_cell.bsic = bsic; - - /* calculate synchronisation value (TODO: only complete for qbits) */ - last_fb->toa -= 23; - qbits = last_fb->toa * 4; - fn_offset = l1s.current_time.fn; // TODO - - if (qbits > QBITS_PER_TDMA) { - qbits -= QBITS_PER_TDMA; - fn_offset -= 1; - } else if (qbits < 0) { - qbits += QBITS_PER_TDMA; - fn_offset += 1; - } - - fnr_delta = last_fb->fnr_report - attempt; - bits_delta = fnr_delta * BITS_PER_TDMA; - - cinfo->fn_offset = fnr_delta; - cinfo->time_alignment = qbits; - cinfo->arfcn = rf_arfcn; - - if (last_fb->toa > bits_delta) - printf("=> DSP reports SB in bit that is %d bits in the " - "future?!?\n", last_fb->toa - bits_delta); - else - printf(" qbits=%u\n", qbits); - - if (l1s.sb.count > 5 && l1s.sb.synced == 0) { - synchronize_tdma(&l1s.serving_cell); - l1s.sb.synced = 1; - } - - /* if we have recived a SYNC burst, update our local GSM time */ - gsm_fn2gsmtime(&l1s.current_time, sb_time.fn + SB2_LATENCY); - /* compute next time from new current time */ - l1s.next_time = l1s.current_time; - l1s_time_inc(&l1s.next_time, 1); - - /* place it in the queue for the layer2 */ - msg = l1_create_l2_msg(L1CTL_NEW_CCCH_RESP, sb_time.fn, - last_fb->snr, rf_arfcn); - l1 = (struct l1ctl_sync_new_ccch_resp *) msgb_put(msg, sizeof(*l1)); - l1->bsic = bsic; - l1_queue_for_l2(msg); - - /* If we call tdma_sched_reset(), which is only needed if there - * are further l1s_sbdet_resp() scheduled, we will bring - * dsp_api.db_r and dsp_api.db_w out of sync because we changed - * dsp_api.db_w for l1s_sbdet_cmd() and canceled - * l1s_sbdet_resp() which would change dsp_api.db_r. The DSP - * however expects dsp_api.db_w and dsp_api.db_r to be in sync - * (either "0 - 0" or "1 - 1"). So we have to bring dsp_api.db_w - * and dsp_api.db_r into sync again, otherwise NB reading will - * complain. We probably don't need the Abort command and could - * just bring dsp_api.db_w and dsp_api.db_r into sync. */ - if (attempt != 2) { - tdma_sched_reset(); - l1s_dsp_abort(); - } - - if (l1s.sb.count > 10 && sb_time.t3 == 41) { - l1s_reset_hw(); - /* enable the MF Task for BCCH reading */ - l1s.mf_tasks |= (1 << MF_TASK_BCCH_NORM); - l1s.mf_tasks |= (1 << MF_TASK_CCCH_COMB); - } else { - /* We have just seen a SCH burst, we know the next one - * is not in less than 7 TDMA frames from now */ - l1s_sb_test(7); - } - - return 0; -} - -static int l1s_sbdet_cmd(__unused uint8_t p1, __unused uint8_t p2, - __unused uint16_t p3) -{ - putchart('S'); - - dsp_api.db_w->d_task_md = SB_DSP_TASK; - dsp_api.ndb->d_fb_mode = 0; /* wideband search */ - dsp_end_scenario(); - - /* Program TPU */ - l1s_rx_win_ctrl(rf_arfcn, L1_RXWIN_SB); - tpu_end_scenario(); - - return 0; -} - -void l1s_sb_test(uint8_t base_fn) -{ -#if 1 - /* This is how it is done by the TSM30 */ - tdma_schedule(base_fn, &l1s_sbdet_cmd, 0, 1, 0); - tdma_schedule(base_fn + 1, &l1s_sbdet_cmd, 0, 2, 0); - tdma_schedule(base_fn + 3, &l1s_sbdet_resp, 0, 1, 0); - tdma_schedule(base_fn + 4, &l1s_sbdet_resp, 0, 2, 0); -#else - tdma_schedule(base_fn, &l1s_sbdet_cmd, 0, 1, 0); - tdma_schedule(base_fn + 1, &l1s_sbdet_resp, 0, 1, 0); - tdma_schedule(base_fn + 2, &l1s_sbdet_resp, 0, 2, 0); -#endif -} - void l1s_tx_apc_helper(void) { int i; |