fixeria has submitted this change. ( https://gerrit.osmocom.org/c/osmocom-bb/+/38744?usp=email )
Change subject: trxcon/l1sched: clarify TDMA Fn (mod 26) maps ......................................................................
trxcon/l1sched: clarify TDMA Fn (mod 26) maps
* Clarify comments, fix 3GPP spec. references * Remove burst tables, refer to doc/l1sched_tch.txt * Rename mappings: include burst letter
Change-Id: Ib664ba643073e7673aa86aa860a1649225c19aa1 --- M src/host/trxcon/src/sched_lchan_tchf.c M src/host/trxcon/src/sched_lchan_tchh.c 2 files changed, 45 insertions(+), 58 deletions(-)
Approvals: Jenkins Builder: Verified pespin: Looks good to me, but someone else must approve osmith: Looks good to me, but someone else must approve fixeria: Looks good to me, approved
diff --git a/src/host/trxcon/src/sched_lchan_tchf.c b/src/host/trxcon/src/sched_lchan_tchf.c index 985bea4..598203a 100644 --- a/src/host/trxcon/src/sched_lchan_tchf.c +++ b/src/host/trxcon/src/sched_lchan_tchf.c @@ -47,22 +47,19 @@ #define BUFPOS(buf, n) &buf[(n) * BPLEN] #define BUFTAIL8(buf) BUFPOS(buf, (BUFMAX - 8))
-/* 3GPP TS 45.009, table 3.2.1.3-{1,3}: AMR on Downlink TCH/F. - * - * +---+---+---+---+---+---+---+---+ - * | a | b | c | d | e | f | g | h | Burst 'a' received first - * +---+---+---+---+---+---+---+---+ - * ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Speech/FACCH frame (bursts 'a' .. 'h') - * - * TDMA frame number of burst 'h' is always used as the table index. */ -static const uint8_t sched_tchf_dl_amr_cmi_map[26] = { +/* ------------------------------------------------------------------ + * 3GPP TS 45.009, table 3.2.1.3-1 + * "TDMA frames for Codec Mode Indication for TCH/AFS, TCH/WFS and O-TCH/WFS" */ + +/* TDMA frame number (mod 26) of burst 'h' (last) is the table index. */ +static const uint8_t sched_tchf_dl_amr_cmi_h_map[26] = { [11] = 1, /* TCH/F: a=4 / h=11 */ [20] = 1, /* TCH/F: a=13 / h=20 */ [3] = 1, /* TCH/F: a=21 / h=3 (21+7=28, 25 is idle -> 29. 29%26=3) */ };
-/* TDMA frame number of burst 'a' should be used as the table index. */ -static const uint8_t sched_tchf_ul_amr_cmi_map[26] = { +/* TDMA frame number (mod 26) of burst 'a' (first) is the table index. */ +static const uint8_t sched_tchf_ul_amr_cmi_a_map[26] = { [0] = 1, /* TCH/F: a=0 */ [8] = 1, /* TCH/F: a=8 */ [17] = 1, /* TCH/F: a=17 */ @@ -166,7 +163,7 @@ * know this before we actually decode the frame) */ amr = 2; rc = gsm0503_tch_afs_decode_dtx(&tch_data[amr], BUFTAIL8(bursts_p), - !sched_tchf_dl_amr_cmi_map[bi->fn % 26], + !sched_tchf_dl_amr_cmi_h_map[bi->fn % 26], lchan->amr.codec, lchan->amr.codecs, &lchan->amr.dl_ft, @@ -304,7 +301,7 @@ break; case GSM48_CMODE_SPEECH_AMR: { - bool amr_fn_is_cmr = !sched_tchf_ul_amr_cmi_map[br->fn % 26]; + bool amr_fn_is_cmr = !sched_tchf_ul_amr_cmi_a_map[br->fn % 26]; unsigned int offset = 0;
if (msg != NULL && msg != msg_facch) { /* TCH/AFS: speech */ diff --git a/src/host/trxcon/src/sched_lchan_tchh.c b/src/host/trxcon/src/sched_lchan_tchh.c index a158bef..359ab37 100644 --- a/src/host/trxcon/src/sched_lchan_tchh.c +++ b/src/host/trxcon/src/sched_lchan_tchh.c @@ -50,16 +50,16 @@ #define BUFPOS(buf, n) &buf[(n) * BPLEN] #define BUFTAIL8(buf) BUFPOS(buf, (BUFMAX - 8))
-/* 3GPP TS 45.009, table 3.2.1.3-{2,4}: AMR on Downlink TCH/H. - * - * +---+---+---+---+---+---+ - * | a | b | c | d | e | f | Burst 'a' received first - * +---+---+---+---+---+---+ - * ^^^^^^^^^^^^^^^^^^^^^^^ FACCH frame (bursts 'a' .. 'f') - * ^^^^^^^^^^^^^^^ Speech frame (bursts 'a' .. 'd') - * - * TDMA frame number of burst 'f' is always used as the table index. */ -static const uint8_t sched_tchh_dl_amr_cmi_map[26] = { +/* ------------------------------------------------------------------ + * 3GPP TS 45.009, table 3.2.1.3-2 + * "TDMA frames for Codec Mode Indication for TCH/AHS, O-TCH/AHS and O-TCH/WHS" + * These mappings are valid for both TCH/H(0) and TCH/H(1). */ + +/* TDMA frame number (mod 26) of burst 'f' (see below) is the table index. + * Even though a TCH/AHS block is interleaved over 4 bursts ('a' .. 'd'), + * we need to "think" 2 TDMA slots ahead because of the way we put bursts + * to the DL buffer (see doc/l1sched_tch.txt). */ +static const uint8_t sched_tchh_dl_amr_cmi_f_map[26] = { [15] = 1, /* TCH/H(0): a=4 / d=10 / f=15 */ [23] = 1, /* TCH/H(0): a=13 / d=19 / f=23 */ [6] = 1, /* TCH/H(0): a=21 / d=2 / f=6 */ @@ -69,8 +69,8 @@ [7] = 1, /* TCH/H(1): a=22 / d=3 / f=7 */ };
-/* TDMA frame number of burst 'a' is always used as the table index. */ -static const uint8_t sched_tchh_ul_amr_cmi_map[26] = { +/* TDMA frame number (mod 26) of burst 'a' (first) is the table index. */ +static const uint8_t sched_tchh_ul_amr_cmi_a_map[26] = { [0] = 1, /* TCH/H(0): a=0 */ [8] = 1, /* TCH/H(0): a=8 */ [17] = 1, /* TCH/H(0): a=17 */ @@ -80,10 +80,11 @@ [18] = 1, /* TCH/H(1): a=18 */ };
-/* FACCH/H channel mappings for DL and UL (see 3GPP TS 45.002, table 1). +/* ------------------------------------------------------------------ + * FACCH/H channel mappings for DL and UL (see 3GPP TS 45.002, table 1). * These mappings are valid for both FACCH/H(0) and FACCH/H(1). */
-/* TDMA frame number of burst 'f' is used as the table index. */ +/* TDMA frame number (mod 26) of burst 'f' (last) is the table index. */ static const uint8_t sched_tchh_dl_facch_f_map[26] = { [15] = 1, /* FACCH/H(0): B0(4,6,8,10,13,15) */ [16] = 1, /* FACCH/H(1): B0(5,7,9,11,14,16) */ @@ -93,7 +94,7 @@ [7] = 1, /* FACCH/H(1): B2(22,24,1,3,5,7) */ };
-/* TDMA frame number of burst 'a' is used as the table index. */ +/* TDMA frame number (mod 26) of burst 'a' (first) is the table index. */ static const uint8_t sched_tchh_dl_facch_a_map[26] = { [4] = 1, /* FACCH/H(0): B0(4,6,8,10,13,15) */ [5] = 1, /* FACCH/H(1): B0(5,7,9,11,14,16) */ @@ -103,8 +104,8 @@ [22] = 1, /* FACCH/H(1): B2(22,24,1,3,5,7) */ };
-/* TDMA frame number of burst 'a' is used as the table index. */ -static const uint8_t sched_tchh_ul_facch_map[26] = { +/* TDMA frame number (mod 26) of burst 'a' (first) is the table index. */ +static const uint8_t sched_tchh_ul_facch_a_map[26] = { [0] = 1, /* FACCH/H(0): B0(0,2,4,6,8,10) */ [1] = 1, /* FACCH/H(1): B0(1,3,5,7,9,11) */ [8] = 1, /* FACCH/H(0): B1(8,10,13,15,17,19) */ @@ -113,22 +114,12 @@ [18] = 1, /* FACCH/H(1): B2(18,20,22,24,1,3) */ };
-/* 3GPP TS 45.002, table 2 in clause 7: Mapping tables for TCH/H2.4 and TCH/H4.8. - * - * +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+ - * | a | b | c | d | e | f | g | h | i | j | k | l | m | n | o | p | q | r | s | t | u | v | - * +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+ - * - * TCH/H(0): B0(0,2,4,6,8,10,13,15,17,19,21,23,0,2,4,6,8,10,13,15,17,19) - * TCH/H(1): B0(1,3,5,7,9,11,14,16,18,20,22,24,1,3,5,7,9,11,14,16,18,20) - * TCH/H(0): B1(8,10,13,15,17,19,21,23,0,2,4,6,8,10,13,15,17,19,21,23,0,2) - * TCH/H(1): B1(9,11,14,16,18,20,22,24,1,3,5,7,9,11,14,16,18,20,22,24,1,3) - * TCH/H(0): B2(17,19,21,23,0,2,4,6,8,10,13,15,17,19,21,23,0,2,4,6,8,10) - * TCH/H(1): B2(18,20,22,24,1,3,5,7,9,11,14,16,18,20,22,24,1,3,5,7,9,11) - * - * TDMA frame number of burst 'a' % 26 is the table index. - * This mapping is valid for both TCH/H(0) and TCH/H(1). */ -static const uint8_t sched_tchh_ul_csd_map[26] = { +/* ------------------------------------------------------------------ + * 3GPP TS 45.002, table 2 in clause 7: Mapping tables for TCH/H2.4 and TCH/H4.8. + * These mappings are valid for both TCH/H(0) and TCH/H(1). */ + +/* TDMA frame number (mod 26) of burst 'a' (first) is the table index. */ +static const uint8_t sched_tchh_ul_csd_a_map[26] = { [0] = 1, /* TCH/H(0): B0(0 ... 19) */ [1] = 1, /* TCH/H(1): B0(1 ... 20) */ [8] = 1, /* TCH/H(0): B1(8 ... 2) */ @@ -137,9 +128,8 @@ [18] = 1, /* TCH/H(1): B2(18 ... 11) */ };
-/* TDMA frame number of burst 'v' % 26 is the table index. - * This mapping is valid for both TCH/H(0) and TCH/H(1). */ -static const uint8_t sched_tchh_dl_csd_map[26] = { +/* TDMA frame number (mod 26) of burst 'v' (last) is the table index. */ +static const uint8_t sched_tchh_dl_csd_v_map[26] = { [19] = 1, /* TCH/H(0): B0(0 ... 19) */ [20] = 1, /* TCH/H(1): B0(1 ... 20) */ [2] = 1, /* TCH/H(0): B1(8 ... 2) */ @@ -265,7 +255,7 @@ amr = 2; rc = gsm0503_tch_ahs_decode_dtx(&tch_data[amr], BUFTAIL8(bursts_p), !sched_tchh_dl_facch_f_map[bi->fn % 26], - !sched_tchh_dl_amr_cmi_map[bi->fn % 26], + !sched_tchh_dl_amr_cmi_f_map[bi->fn % 26], lchan->amr.codec, lchan->amr.codecs, &lchan->amr.dl_ft, @@ -294,7 +284,7 @@ /* FACCH/H does not steal TCH/H4.8 frames, but only disturbs some bits */ if (sched_tchh_dl_facch_f_map[bi->fn % 26]) decode_hr_facch(lchan); - if (!sched_tchh_dl_csd_map[bi->fn % 26]) + if (!sched_tchh_dl_csd_v_map[bi->fn % 26]) return 0; rc = gsm0503_tch_hr48_decode(&tch_data[0], BUFPOS(bursts_p, 0), &n_errors, &n_bits_total); @@ -304,7 +294,7 @@ /* FACCH/H does not steal TCH/H2.4 frames, but only disturbs some bits */ if (sched_tchh_dl_facch_f_map[bi->fn % 26]) decode_hr_facch(lchan); - if (!sched_tchh_dl_csd_map[bi->fn % 26]) + if (!sched_tchh_dl_csd_v_map[bi->fn % 26]) return 0; rc = gsm0503_tch_hr24_decode(&tch_data[0], BUFPOS(bursts_p, 0), &n_errors, &n_bits_total); @@ -373,12 +363,12 @@ /* Align transmission of the first frame */ switch (lchan->tch_mode) { case GSM48_CMODE_SIGN: - if (!sched_tchh_ul_facch_map[br->fn % 26]) + if (!sched_tchh_ul_facch_a_map[br->fn % 26]) return 0; break; case GSM48_CMODE_DATA_6k0: case GSM48_CMODE_DATA_3k6: - if (!sched_tchh_ul_csd_map[br->fn % 26]) + if (!sched_tchh_ul_csd_a_map[br->fn % 26]) return 0; break; } @@ -400,14 +390,14 @@ case GSM48_CMODE_DATA_6k0: case GSM48_CMODE_DATA_3k6: /* CSD: skip dequeueing/encoding, send 2 more bursts */ - if (!sched_tchh_ul_csd_map[br->fn % 26]) + if (!sched_tchh_ul_csd_a_map[br->fn % 26]) goto send_burst; break; }
/* dequeue a pair of TCH and FACCH frames */ msg_tch = l1sched_lchan_prim_dequeue_tch(lchan, false); - if (sched_tchh_ul_facch_map[br->fn % 26]) + if (sched_tchh_ul_facch_a_map[br->fn % 26]) msg_facch = l1sched_lchan_prim_dequeue_tch(lchan, true); else msg_facch = NULL; @@ -417,7 +407,7 @@ /* populate the buffer with bursts */ switch (lchan->tch_mode) { case GSM48_CMODE_SIGN: - if (!sched_tchh_ul_facch_map[br->fn % 26]) + if (!sched_tchh_ul_facch_a_map[br->fn % 26]) goto send_burst; /* XXX: should not happen */ if (msg == NULL) msg = l1sched_lchan_prim_dummy_lapdm(lchan); @@ -439,7 +429,7 @@ break; case GSM48_CMODE_SPEECH_AMR: { - bool amr_fn_is_cmr = !sched_tchh_ul_amr_cmi_map[br->fn % 26]; + bool amr_fn_is_cmr = !sched_tchh_ul_amr_cmi_a_map[br->fn % 26]; unsigned int offset = 0;
if (msg != NULL && msg != msg_facch) { /* TCH/AHS: speech */
-
fixeria