#ifndef _CALYPSO_TPU_H
#define _CALYPSO_TPU_H
+#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)
+
/* Assert or de-assert TPU reset */
void tpu_reset(int active);
/* Enable or Disable a new scenario loaded into the TPU */
extern l1s_cb_t l1s_cb;
+void l1s_reset_hw(void);
+void synchronize_tdma(struct l1_cell_info *cinfo);
+void l1s_time_inc(struct gsm_time *time, uint32_t delta_fn);
+void l1s_time_dump(const struct gsm_time *time);
+
#endif /* _L1_SYNC_H */
layer1_SRCS=avg.c agc.c afc.c sync.c tdma_sched.c tpu_window.c init.c l23_api.c \
mframe_sched.c sched_gsmtime.c async.c
-layer1_SRCS += prim_pm.c prim_rach.c prim_tx_nb.c prim_rx_nb.c
+layer1_SRCS += prim_pm.c prim_rach.c prim_tx_nb.c prim_rx_nb.c prim_fbsb.c
--- /dev/null
+/* Layer 1 - FCCH and SCH burst handling */
+
+/* (C) 2010 by 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 General Public License as published by
+ * the Free Software Foundation; either version 2 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 General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ */
+
+#include <stdint.h>
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+
+#include <defines.h>
+#include <debug.h>
+#include <memory.h>
+#include <byteorder.h>
+#include <osmocore/gsm_utils.h>
+#include <osmocore/msgb.h>
+#include <calypso/dsp_api.h>
+#include <calypso/irq.h>
+#include <calypso/tpu.h>
+#include <calypso/tsp.h>
+#include <calypso/dsp.h>
+#include <calypso/timer.h>
+#include <comm/sercomm.h>
+
+#include <layer1/sync.h>
+#include <layer1/afc.h>
+#include <layer1/tdma_sched.h>
+#include <layer1/mframe_sched.h>
+#include <layer1/tpu_window.h>
+#include <layer1/l23_api.h>
+
+#include <l1a_l23_interface.h>
+
+extern uint16_t rf_arfcn; // TODO
+
+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;
+}
+
+/* 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 ********************************************************/
+
+/* 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;
+}
+
+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;
+}
+
+/* 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
+}
+
+
#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);
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)
{
#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;
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;
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;
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;
projects / osmocom-bb.git / commitdiff