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Diffstat (limited to 'Src/osmolib/src/target/firmware/layer1/prim_rx_nb.c')
-rw-r--r--Src/osmolib/src/target/firmware/layer1/prim_rx_nb.c215
1 files changed, 215 insertions, 0 deletions
diff --git a/Src/osmolib/src/target/firmware/layer1/prim_rx_nb.c b/Src/osmolib/src/target/firmware/layer1/prim_rx_nb.c
new file mode 100644
index 0000000..7eb4548
--- /dev/null
+++ b/Src/osmolib/src/target/firmware/layer1/prim_rx_nb.c
@@ -0,0 +1,215 @@
+/* Layer 1 - Receiving Normal Bursts */
+
+/* (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 <osmocom/gsm/gsm_utils.h>
+#include <osmocom/core/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/toa.h>
+#include <layer1/tdma_sched.h>
+#include <layer1/mframe_sched.h>
+#include <layer1/tpu_window.h>
+#include <layer1/l23_api.h>
+#include <layer1/rfch.h>
+#include <layer1/prim.h>
+
+#include <l1ctl_proto.h>
+
+struct l1s_rxnb_state {
+ struct l1s_meas_hdr meas[4];
+
+ struct msgb *msg;
+ struct l1ctl_info_dl *dl;
+ struct l1ctl_data_ind *di;
+};
+
+static struct l1s_rxnb_state rxnb;
+
+static int l1s_nb_resp(__unused uint8_t p1, uint8_t burst_id, uint16_t p3)
+{
+ struct gsm_time rx_time;
+ uint8_t mf_task_id = p3 & 0xff;
+ uint8_t mf_task_flags = p3 >> 8;
+ uint16_t rf_arfcn;
+ uint8_t tsc, tn;
+
+ putchart('n');
+
+ /* just for debugging, d_task_d should not be 0 */
+ if (dsp_api.db_r->d_task_d == 0) {
+ puts("EMPTY\n");
+ return 0;
+ }
+
+ /* DSP burst ID needs to correspond with what we expect */
+ if (dsp_api.db_r->d_burst_d != burst_id) {
+ printf("BURST ID %u!=%u\n", dsp_api.db_r->d_burst_d, burst_id);
+ return 0;
+ }
+
+ /* get radio parameters for _this_ burst */
+ gsm_fn2gsmtime(&rx_time, l1s.current_time.fn - 1);
+ rfch_get_params(&rx_time, &rf_arfcn, &tsc, &tn);
+
+ /* collect measurements */
+ rxnb.meas[burst_id].toa_qbit = dsp_api.db_r->a_serv_demod[D_TOA];
+ rxnb.meas[burst_id].pm_dbm8 =
+ agc_inp_dbm8_by_pm(dsp_api.db_r->a_serv_demod[D_PM] >> 3);
+ rxnb.meas[burst_id].freq_err =
+ ANGLE_TO_FREQ(dsp_api.db_r->a_serv_demod[D_ANGLE]);
+ rxnb.meas[burst_id].snr = dsp_api.db_r->a_serv_demod[D_SNR];
+
+ /* feed computed frequency error into AFC loop */
+ if (rxnb.meas[burst_id].snr > AFC_SNR_THRESHOLD)
+ afc_input(rxnb.meas[burst_id].freq_err, rf_arfcn, 1);
+ else
+ afc_input(rxnb.meas[burst_id].freq_err, rf_arfcn, 0);
+
+ /* feed computed TOA into TA loop */
+ toa_input(rxnb.meas[burst_id].toa_qbit << 2, rxnb.meas[burst_id].snr);
+
+ /* Tell the RF frontend to set the gain appropriately */
+ rffe_compute_gain(rxnb.meas[burst_id].pm_dbm8/8, CAL_DSP_TGT_BB_LVL);
+
+ /* 4th burst, get frame data */
+ if (dsp_api.db_r->d_burst_d == 3) {
+ uint8_t i;
+ uint16_t num_biterr;
+ uint32_t avg_snr = 0;
+ int32_t avg_dbm8 = 0;
+
+ /* Get radio parameters for the first burst */
+ gsm_fn2gsmtime(&rx_time, l1s.current_time.fn - 4);
+ rfch_get_params(&rx_time, &rf_arfcn, &tsc, &tn);
+
+ /* Set Channel Number depending on MFrame Task ID */
+ rxnb.dl->chan_nr = mframe_task2chan_nr(mf_task_id, tn);
+
+ /* Set SACCH indication in Link IDentifier */
+ if (mf_task_flags & MF_F_SACCH)
+ rxnb.dl->link_id = 0x40;
+ else
+ rxnb.dl->link_id = 0x00;
+
+ rxnb.dl->band_arfcn = htons(rf_arfcn);
+
+ rxnb.dl->frame_nr = htonl(rx_time.fn);
+
+ /* compute average snr and rx level */
+ for (i = 0; i < 4; ++i) {
+ avg_snr += rxnb.meas[i].snr;
+ avg_dbm8 += rxnb.meas[i].pm_dbm8;
+ }
+ rxnb.dl->snr = avg_snr / 4;
+ rxnb.dl->rx_level = dbm2rxlev(avg_dbm8 / (8*4));
+
+ num_biterr = dsp_api.ndb->a_cd[2] & 0xffff;
+ if (num_biterr > 0xff)
+ rxnb.dl->num_biterr = 0xff;
+ else
+ rxnb.dl->num_biterr = num_biterr;
+
+ rxnb.dl->fire_crc = ((dsp_api.ndb->a_cd[0] & 0xffff) & ((1 << B_FIRE1) | (1 << B_FIRE0))) >> B_FIRE0;
+
+ /* update rx level for pm report */
+ pu_update_rx_level(rxnb.dl->rx_level);
+
+ /* copy actual data, skipping the information block [0,1,2] */
+ dsp_memcpy_from_api(rxnb.di->data, &dsp_api.ndb->a_cd[3], 23, 0);
+
+ l1_queue_for_l2(rxnb.msg);
+ rxnb.msg = NULL; rxnb.dl = NULL; rxnb.di = NULL;
+
+ /* clear downlink task */
+ dsp_api.db_w->d_task_d = 0;
+ }
+
+ /* mark READ page as being used */
+ dsp_api.r_page_used = 1;
+
+ return 0;
+}
+
+static int l1s_nb_cmd(__unused uint8_t p1, uint8_t burst_id,
+ __unused uint16_t p3)
+{
+ uint16_t arfcn;
+ uint8_t tsc, tn;
+
+ putchart('N');
+
+ if (burst_id == 1) {
+ /* allocate message only at 2nd burst in case of
+ * consecutive/overlapping normal burst RX tasks */
+ /* FIXME: we actually want all allocation out of L1S! */
+ if (rxnb.msg) {
+ /* Can happen when resetting ... */
+ printf("nb_cmd(0) and rxnb.msg != NULL\n");
+ msgb_free(rxnb.msg);
+ }
+ /* allocate msgb as needed. FIXME: from L1A ?? */
+ rxnb.msg = l1ctl_msgb_alloc(L1CTL_DATA_IND);
+ if (!rxnb.msg)
+ printf("nb_cmd(0): unable to allocate msgb\n");
+ rxnb.dl = (struct l1ctl_info_dl *) msgb_put(rxnb.msg, sizeof(*rxnb.dl));
+ rxnb.di = (struct l1ctl_data_ind *) msgb_put(rxnb.msg, sizeof(*rxnb.di));
+ }
+
+ rfch_get_params(&l1s.next_time, &arfcn, &tsc, &tn);
+
+ /* DDL_DSP_TASK, four normal bursts */
+ dsp_load_tch_param(&l1s.next_time,
+ SIG_ONLY_MODE, SDCCH_4, 0, 0, 0, tn);
+
+ dsp_load_rx_task(ALLC_DSP_TASK, burst_id, tsc);
+
+ l1s_rx_win_ctrl(arfcn, L1_RXWIN_NB, 0);
+
+ return 0;
+}
+
+const struct tdma_sched_item nb_sched_set[] = {
+ SCHED_ITEM_DT(l1s_nb_cmd, 0, 0, 0), SCHED_END_FRAME(),
+ SCHED_ITEM_DT(l1s_nb_cmd, 0, 0, 1), SCHED_END_FRAME(),
+ SCHED_ITEM(l1s_nb_resp, -4, 0, 0), SCHED_ITEM_DT(l1s_nb_cmd, 0, 0, 2), SCHED_END_FRAME(),
+ SCHED_ITEM(l1s_nb_resp, -4, 0, 1), SCHED_ITEM_DT(l1s_nb_cmd, 0, 0, 3), SCHED_END_FRAME(),
+ SCHED_ITEM(l1s_nb_resp, -4, 0, 2), SCHED_END_FRAME(),
+ SCHED_ITEM(l1s_nb_resp, -4, 0, 3), SCHED_END_FRAME(),
+ SCHED_END_SET()
+};