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-rw-r--r--src/host/trxcon/Makefile.am1
-rw-r--r--src/host/trxcon/sched_lchan_tchh.c183
-rw-r--r--src/host/trxcon/sched_prim.c19
-rw-r--r--src/host/trxcon/sched_trx.h16
-rw-r--r--src/host/trxcon/scheduler.h4
5 files changed, 207 insertions, 16 deletions
diff --git a/src/host/trxcon/Makefile.am b/src/host/trxcon/Makefile.am
index c9cc170a..7095cb59 100644
--- a/src/host/trxcon/Makefile.am
+++ b/src/host/trxcon/Makefile.am
@@ -35,6 +35,7 @@ trxcon_SOURCES += \
sched_lchan_desc.c \
sched_lchan_xcch.c \
sched_lchan_tchf.c \
+ sched_lchan_tchh.c \
sched_lchan_rach.c \
sched_lchan_sch.c \
sched_mframe.c \
diff --git a/src/host/trxcon/sched_lchan_tchh.c b/src/host/trxcon/sched_lchan_tchh.c
new file mode 100644
index 00000000..316f995b
--- /dev/null
+++ b/src/host/trxcon/sched_lchan_tchh.c
@@ -0,0 +1,183 @@
+/*
+ * OsmocomBB <-> SDR connection bridge
+ * TDMA scheduler: handlers for DL / UL bursts on logical channels
+ *
+ * (C) 2018 by Vadim Yanitskiy <axilirator@gmail.com>
+ *
+ * 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 <errno.h>
+#include <stdint.h>
+#include <stdbool.h>
+
+#include "scheduler.h"
+#include "sched_trx.h"
+
+static const uint8_t tch_h0_traffic_block_map[3][4] = {
+ /* B0(0,2,4,6), B1(4,6,8,10), B2(8,10,0,2) */
+ { 0, 2, 4, 6 },
+ { 4, 6, 8, 10 },
+ { 8, 10, 0, 2 },
+};
+
+static const uint8_t tch_h1_traffic_block_map[3][4] = {
+ /* B0(1,3,5,7), B1(5,7,9,11), B2(9,11,1,3) */
+ { 1, 3, 5, 7 },
+ { 5, 7, 9, 11 },
+ { 9, 11, 1, 3 },
+};
+
+static const uint8_t tch_h0_dl_facch_block_map[3][6] = {
+ /* B0(4,6,8,10,13,15), B1(13,15,17,19,21,23), B2(21,23,0,2,4,6) */
+ { 4, 6, 8, 10, 13, 15 },
+ { 13, 15, 17, 19, 21, 23 },
+ { 21, 23, 0, 2, 4, 6 },
+};
+
+static const uint8_t tch_h0_ul_facch_block_map[3][6] = {
+ /* B0(0,2,4,6,8,10), B1(8,10,13,15,17,19), B2(17,19,21,23,0,2) */
+ { 0, 2, 4, 6, 8, 10 },
+ { 8, 10, 13, 15, 17, 19 },
+ { 17, 19, 21, 23, 0, 2 },
+};
+
+static const uint8_t tch_h1_dl_facch_block_map[3][6] = {
+ /* B0(5,7,9,11,14,16), B1(14,16,18,20,22,24), B2(22,24,1,3,5,7) */
+ { 5, 7, 9, 11, 14, 16 },
+ { 14, 16, 18, 20, 22, 24 },
+ { 22, 24, 1, 3, 5, 7 },
+};
+
+const uint8_t tch_h1_ul_facch_block_map[3][6] = {
+ /* B0(1,3,5,7,9,11), B1(9,11,14,16,18,20), B2(18,20,22,24,1,3) */
+ { 1, 3, 5, 7, 9, 11 },
+ { 9, 11, 14, 16, 18, 20 },
+ { 18, 20, 22, 24, 1, 3 },
+};
+
+/**
+ * Can a TCH/H block transmission be initiated / finished
+ * on a given frame number and a given channel type?
+ *
+ * See GSM 05.02, clause 7, table 1
+ *
+ * @param chan channel type (TRXC_TCHH_0 or TRXC_TCHH_1)
+ * @param fn the current frame number
+ * @param ul Uplink or Downlink?
+ * @param facch FACCH/H or traffic?
+ * @param start init or end of transmission?
+ * @return true (yes) or false (no)
+ */
+bool sched_tchh_block_map_fn(enum trx_lchan_type chan,
+ uint32_t fn, bool ul, bool facch, bool start)
+{
+ uint8_t fn_mf;
+ int i = 0;
+
+ /* Just to be sure */
+ OSMO_ASSERT(chan == TRXC_TCHH_0 || chan == TRXC_TCHH_1);
+
+ /* Calculate a modulo */
+ fn_mf = facch ? (fn % 26) : (fn % 13);
+
+#define MAP_GET_POS(map) \
+ (start ? 0 : ARRAY_SIZE(map[i]) - 1)
+
+#define BLOCK_MAP_FN(map) \
+ do { \
+ if (map[i][MAP_GET_POS(map)] == fn_mf) \
+ return true; \
+ } while (++i < ARRAY_SIZE(map))
+
+ /* Choose a proper block map */
+ if (facch) {
+ if (ul) {
+ if (chan == TRXC_TCHH_0)
+ BLOCK_MAP_FN(tch_h0_ul_facch_block_map);
+ else
+ BLOCK_MAP_FN(tch_h1_ul_facch_block_map);
+ } else {
+ if (chan == TRXC_TCHH_0)
+ BLOCK_MAP_FN(tch_h0_dl_facch_block_map);
+ else
+ BLOCK_MAP_FN(tch_h1_dl_facch_block_map);
+ }
+ } else {
+ if (chan == TRXC_TCHH_0)
+ BLOCK_MAP_FN(tch_h0_traffic_block_map);
+ else
+ BLOCK_MAP_FN(tch_h1_traffic_block_map);
+ }
+
+ return false;
+}
+
+/**
+ * Calculates a frame number of the first burst
+ * using given frame number of the last burst.
+ *
+ * See GSM 05.02, clause 7, table 1
+ *
+ * @param chan channel type (TRXC_TCHH_0 or TRXC_TCHH_1)
+ * @param last_fn frame number of the last burst
+ * @param facch FACCH/H or traffic?
+ * @return either frame number of the first burst,
+ * or fn=last_fn if calculation failed
+ */
+uint32_t sched_tchh_block_dl_first_fn(enum trx_lchan_type chan,
+ uint32_t last_fn, bool facch)
+{
+ uint8_t fn_mf, fn_diff;
+ int i = 0;
+
+ /* Just to be sure */
+ OSMO_ASSERT(chan == TRXC_TCHH_0 || chan == TRXC_TCHH_1);
+
+ /* Calculate a modulo */
+ fn_mf = facch ? (last_fn % 26) : (last_fn % 13);
+
+#define BLOCK_FIRST_FN(map) \
+ do { \
+ if (map[i][ARRAY_SIZE(map[i]) - 1] == fn_mf) { \
+ fn_diff = TDMA_FN_DIFF(fn_mf, map[i][0]); \
+ return TDMA_FN_SUB(last_fn, fn_diff); \
+ } \
+ } while (++i < ARRAY_SIZE(map))
+
+ /* Choose a proper block map */
+ if (facch) {
+ if (chan == TRXC_TCHH_0)
+ BLOCK_FIRST_FN(tch_h0_dl_facch_block_map);
+ else
+ BLOCK_FIRST_FN(tch_h1_dl_facch_block_map);
+ } else {
+ if (chan == TRXC_TCHH_0)
+ BLOCK_FIRST_FN(tch_h0_traffic_block_map);
+ else
+ BLOCK_FIRST_FN(tch_h1_traffic_block_map);
+ }
+
+ LOGP(DSCHD, LOGL_ERROR, "Failed to calculate TDMA "
+ "frame number of the first burst of %s block, "
+ "using the current fn=%u\n", facch ?
+ "FACCH/H" : "TCH/H", last_fn);
+
+ /* Couldn't calculate the first fn, return the last */
+ return last_fn;
+}
diff --git a/src/host/trxcon/sched_prim.c b/src/host/trxcon/sched_prim.c
index e663bc3f..6b160d1c 100644
--- a/src/host/trxcon/sched_prim.c
+++ b/src/host/trxcon/sched_prim.c
@@ -248,23 +248,10 @@ static struct trx_ts_prim *prim_dequeue_tch_h(struct llist_head *queue,
{
struct trx_ts_prim *facch;
struct trx_ts_prim *tch;
- bool facch_now = false;
- uint32_t fn_mf;
+ bool facch_now;
- /* Traffic multiframe period */
- fn_mf = fn % 26;
-
- /* FACCH/H0 frame alignment */
- if (lchan_type == TRXC_TCHH_0)
- if (fn_mf == 0 || fn_mf == 8 || fn_mf == 17)
- facch_now = true;
-
- /* FACCH/H1 frame alignment */
- if (lchan_type == TRXC_TCHH_1)
- if (fn_mf == 1 || fn_mf == 9 || fn_mf == 18)
- facch_now = true;
-
- /* If FACCH/H is not allowed for a given frame number */
+ /* May we initiate an UL FACCH/H frame transmission now? */
+ facch_now = sched_tchh_facch_start(lchan_type, fn, true);
if (!facch_now) /* Just dequeue a TCH/H prim */
goto no_facch;
diff --git a/src/host/trxcon/sched_trx.h b/src/host/trxcon/sched_trx.h
index 730923b4..2c8b4d8f 100644
--- a/src/host/trxcon/sched_trx.h
+++ b/src/host/trxcon/sched_trx.h
@@ -323,3 +323,19 @@ int sched_send_dt_ind(struct trx_instance *trx, struct trx_ts *ts,
int bit_error_count, bool dec_failed, bool traffic);
int sched_send_dt_conf(struct trx_instance *trx, struct trx_ts *ts,
struct trx_lchan_state *lchan, uint32_t fn, bool traffic);
+
+/* Interleaved TCH/H block TDMA frame mapping */
+uint32_t sched_tchh_block_dl_first_fn(enum trx_lchan_type chan,
+ uint32_t last_fn, bool facch);
+bool sched_tchh_block_map_fn(enum trx_lchan_type chan,
+ uint32_t fn, bool ul, bool facch, bool start);
+
+#define sched_tchh_traffic_start(chan, fn, ul) \
+ sched_tchh_block_map_fn(chan, fn, ul, 0, 1)
+#define sched_tchh_traffic_end(chan, fn, ul) \
+ sched_tchh_block_map_fn(chan, fn, ul, 0, 0)
+
+#define sched_tchh_facch_start(chan, fn, ul) \
+ sched_tchh_block_map_fn(chan, fn, ul, 1, 1)
+#define sched_tchh_facch_end(chan, fn, ul) \
+ sched_tchh_block_map_fn(chan, fn, ul, 1, 0)
diff --git a/src/host/trxcon/scheduler.h b/src/host/trxcon/scheduler.h
index fccf7d23..7ab17ab5 100644
--- a/src/host/trxcon/scheduler.h
+++ b/src/host/trxcon/scheduler.h
@@ -17,6 +17,10 @@
((a + GSM_HYPERFRAME - b) % GSM_HYPERFRAME)
#define TDMA_FN_INC(fn) \
TDMA_FN_SUM(fn, 1)
+#define TDMA_FN_MIN(a, b) \
+ (a < b ? a : b)
+#define TDMA_FN_DIFF(a, b) \
+ TDMA_FN_MIN(TDMA_FN_SUB(a, b), TDMA_FN_SUB(b, a))
enum tdma_sched_clck_state {
SCH_CLCK_STATE_WAIT,