aboutsummaryrefslogtreecommitdiffstats
path: root/src/mslot_class.c
blob: 2a482f18a962fc9fb90d40d838f9b1067715eb9d (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
/* mslot_class.c
 *
 * Copyright (C) 2012 Ivan Klyuchnikov
 * Copyright (C) 2012 Andreas Eversberg <jolly@eversberg.eu>
 * Copyright (C) 2013 by Holger Hans Peter Freyther
 * Copyright (C) 2017 by sysmocom - s.f.m.c. GmbH <info@sysmocom.de>
 *
 * 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., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 */

#include <mslot_class.h>
#include <gprs_debug.h>

#include <osmocom/core/bits.h>
#include <osmocom/core/utils.h>
#include <osmocom/core/logging.h>

#include <errno.h>

/* 3GPP TS 45.002 Annex B Table B.1 */

struct gprs_ms_multislot_class {
	uint8_t rx, tx, sum;	/* Maximum Number of Slots: RX, Tx, Sum Rx+Tx */
	uint8_t ta, tb, ra, rb;	/* Minimum Number of Slots */
	uint8_t type; /* Type of Mobile */
};

static const struct gprs_ms_multislot_class gprs_ms_multislot_class[] = {
	/* M-S Class |  Max # of slots |       Min # of slots      | Type */
	/*           | Rx     Tx   Sum |  Tta    Ttb    Tra    Trb |      */
	/* N/A */ { MS_NA, MS_NA, MS_NA, MS_NA, MS_NA, MS_NA, MS_NA, MS_NA },
	/*  1 */  {   1,     1,     2,     3,     2,     4,     2,     1 },
	/*  2 */  {   2,     1,     3,     3,     2,     3,     1,     1 },
	/*  3 */  {   2,     2,     3,     3,     2,     3,     1,     1 },
	/*  4 */  {   3,     1,     4,     3,     1,     3,     1,     1 },
	/*  5 */  {   2,     2,     4,     3,     1,     3,     1,     1 },
	/*  6 */  {   3,     2,     4,     3,     1,     3,     1,     1 },
	/*  7 */  {   3,     3,     4,     3,     1,     3,     1,     1 },
	/*  8 */  {   4,     1,     5,     3,     1,     2,     1,     1 },
	/*  9 */  {   3,     2,     5,     3,     1,     2,     1,     1 },
	/* 10 */  {   4,     2,     5,     3,     1,     2,     1,     1 },
	/* 11 */  {   4,     3,     5,     3,     1,     2,     1,     1 },
	/* 12 */  {   4,     4,     5,     2,     1,     2,     1,     1 },
	/* 13 */  {   3,     3,   MS_NA, MS_NA, MS_A,    3,   MS_A,    2 },
	/* 14 */  {   4,     4,   MS_NA, MS_NA, MS_A,    3,   MS_A,    2 },
	/* 15 */  {   5,     5,   MS_NA, MS_NA, MS_A,    3,   MS_A,    2 },
	/* 16 */  {   6,     6,   MS_NA, MS_NA, MS_A,    2,   MS_A,    2 },
	/* 17 */  {   7,     7,   MS_NA, MS_NA, MS_A,    1,     0,     2 },
	/* 18 */  {   8,     8,   MS_NA, MS_NA,   0,     0,     0,     2 },
	/* 19 */  {   6,     2,   MS_NA,   3,   MS_B,    2,   MS_C,    1 },
	/* 20 */  {   6,     3,   MS_NA,   3,   MS_B,    2,   MS_C,    1 },
	/* 21 */  {   6,     4,   MS_NA,   3,   MS_B,    2,   MS_C,    1 },
	/* 22 */  {   6,     4,   MS_NA,   2,   MS_B,    2,   MS_C,    1 },
	/* 23 */  {   6,     6,   MS_NA,   2,   MS_B,    2,   MS_C,    1 },
	/* 24 */  {   8,     2,   MS_NA,   3,   MS_B,    2,   MS_C,    1 },
	/* 25 */  {   8,     3,   MS_NA,   3,   MS_B,    2,   MS_C,    1 },
	/* 26 */  {   8,     4,   MS_NA,   3,   MS_B,    2,   MS_C,    1 },
	/* 27 */  {   8,     4,   MS_NA,   2,   MS_B,    2,   MS_C,    1 },
	/* 28 */  {   8,     6,   MS_NA,   2,   MS_B,    2,   MS_C,    1 },
	/* 29 */  {   8,     8,   MS_NA,   2,   MS_B,    2,   MS_C,    1 },
	/* 30 */  {   5,     1,     6,     2,     1,     1,     1,     1 },
	/* 31 */  {   5,     2,     6,     2,     1,     1,     1,     1 },
	/* 32 */  {   5,     3,     6,     2,     1,     1,     1,     1 },
	/* 33 */  {   5,     4,     6,     2,     1,     1,     1,     1 },
	/* 34 */  {   5,     5,     6,     2,     1,     1,     1,     1 },
	/* 35 */  {   5,     1,     6,     2,     1,   MS_TO,   1,     1 },
	/* 36 */  {   5,     2,     6,     2,     1,   MS_TO,   1,     1 },
	/* 37 */  {   5,     3,     6,     2,     1,   MS_TO,   1,     1 },
	/* 38 */  {   5,     4,     6,     2,     1,   MS_TO,   1,     1 },
	/* 39 */  {   5,     5,     6,     2,     1,   MS_TO,   1,     1 },
	/* 40 */  {   6,     1,     7,     1,     1,     1,   MS_TO,   1 },
	/* 41 */  {   6,     2,     7,     1,     1,     1,   MS_TO,   1 },
	/* 42 */  {   6,     3,     7,     1,     1,     1,   MS_TO,   1 },
	/* 43 */  {   6,     4,     7,     1,     1,     1,   MS_TO,   1 },
	/* 44 */  {   6,     5,     7,     1,     1,     1,   MS_TO,   1 },
	/* 45 */  {   6,     6,     7,     1,     1,     1,   MS_TO,   1 },
};

static inline const struct gprs_ms_multislot_class *get_mslot_table(uint8_t ms_cl)
{
	uint8_t index = ms_cl ? ms_cl : DEFAULT_MSLOT_CLASS;

	if (ms_cl >= ARRAY_SIZE(gprs_ms_multislot_class))
		index = 0;

	return &gprs_ms_multislot_class[index];
}

uint8_t mslot_class_max()
{
	return ARRAY_SIZE(gprs_ms_multislot_class);
}

uint8_t mslot_class_get_ta(uint8_t ms_cl)
{
	return get_mslot_table(ms_cl)->ta;
}

/* TODO: Set it to 1 if FH is implemented and enabled
 * MS_A and MS_B are 0 iff FH is disabled and there is no Tx/Rx change.
 * This is never the case with the current implementation, so 1 will always be used. */
uint8_t mslot_class_get_tb(uint8_t ms_cl)
{
	const struct gprs_ms_multislot_class *t = get_mslot_table(ms_cl);

	switch (t->tb) {
	case MS_A:
		return 0;
	case MS_B:
		return 1;
	default:
		return t->tb;
	}
}

uint8_t mslot_class_get_ra(uint8_t ms_cl, uint8_t ta)
{
	const struct gprs_ms_multislot_class *t = get_mslot_table(ms_cl);

	switch (t->ra) {
	case MS_TO:
		return ta + 1;
	default:
		return t->ra;
	}
}

uint8_t mslot_class_get_rb(uint8_t ms_cl, uint8_t ta)
{
	const struct gprs_ms_multislot_class *t = get_mslot_table(ms_cl);

	switch (t->rb) {
	case MS_A:
		return 0;
	case MS_C:
		return 1;
	case MS_TO:
		return ta;
	default:
		return t->rb;
	}
}

uint8_t mslot_class_get_tx(uint8_t ms_cl)
{
	return get_mslot_table(ms_cl)->tx;
}

uint8_t mslot_class_get_rx(uint8_t ms_cl)
{
	return get_mslot_table(ms_cl)->rx;
}

uint8_t mslot_class_get_sum(uint8_t ms_cl)
{
	return get_mslot_table(ms_cl)->sum;
}

uint8_t mslot_class_get_type(uint8_t ms_cl)
{
	return get_mslot_table(ms_cl)->type;
}

/*! Fill in RX mask table for a given MS Class
 *
 *  \param[in] ms_cl MS Class pointer
 *  \param[in] num_tx Number of TX slots to consider
 *  \param[out] rx_mask RX mask table
 */
void mslot_fill_rx_mask(uint8_t mslot_class, uint8_t num_tx, uint8_t *rx_mask)
{
	static const char *digit[10] = { "0","1","2","3","4","5","6","7","8","9" };
	uint8_t Tx = mslot_class_get_tx(mslot_class),     /* Max number of Tx slots */
		Sum = mslot_class_get_sum(mslot_class),	  /* Max number of Tx + Rx slots */
		Type = mslot_class_get_type(mslot_class), /* Type of Mobile */
		Tta = mslot_class_get_ta(mslot_class),    /* Minimum number of slots */
		Ttb = mslot_class_get_tb(mslot_class),
		/* FIXME: use actual TA offset for computation - make sure to adjust "1 + MS_TO" accordingly
		   see also "Offset required" bit in 3GPP TS 24.008 §10.5.1.7 */
		Tra = mslot_class_get_ra(mslot_class, 0),
		Trb = mslot_class_get_rb(mslot_class, 0);

	if (num_tx == 1) /* it's enough to log this once per TX slot set iteration */
		LOGP(DRLCMAC, LOGL_DEBUG,
		     "Rx=%d Tx=%d Sum Rx+Tx=%s, Tta=%s Ttb=%d, Tra=%d Trb=%d, Type=%d\n",
		     mslot_class_get_rx(mslot_class), Tx,
		     (Sum == MS_NA) ? "N/A" : digit[Sum],
		     (Tta == MS_NA) ? "N/A" : digit[Tta], Ttb, Tra, Trb, Type);

	if (Type == 1) {
		rx_mask[MASK_TT] = (0x100 >> OSMO_MAX(Ttb, Tta)) - 1;
		rx_mask[MASK_TT] &= ~((1 << (Trb + num_tx)) - 1);
		rx_mask[MASK_TR] = (0x100 >> Ttb) - 1;
		rx_mask[MASK_TR] &= ~((1 << (OSMO_MAX(Trb, Tra) + num_tx)) - 1);
	} else {
		/* Class type 2 MS have independant RX and TX */
		rx_mask[MASK_TT] = 0xff;
		rx_mask[MASK_TR] = 0xff;
	}

	rx_mask[MASK_TT] = (rx_mask[MASK_TT] << 3) | (rx_mask[MASK_TT] >> 5);
	rx_mask[MASK_TR] = (rx_mask[MASK_TR] << 3) | (rx_mask[MASK_TR] >> 5);
}

/* look for USF, don't use USF=7 */
int8_t find_free_usf(uint8_t usf_map)
{
	uint8_t usf;

	if (usf_map == (1 << 7) - 1)
		return -1;

	for (usf = 0; usf < 7; usf++) {
		if (!(usf_map & (1 << usf)))
			return usf;
	}

	return -1;
}

/* look for USF, don't use USF=7 */
int8_t find_free_tfi(uint32_t tfi_map)
{
	int8_t tfi;

	if (tfi_map == NO_FREE_TFI)
		return -1;

	for (tfi = 0; tfi < 32; tfi++) {
		if (!(tfi_map & (1 << tfi)))
			return tfi;
	}

	return -1;
}

void masked_override_with(char *buf, uint8_t mask, char set_char)
{
	int i;
	for (i = 0; mask; i++, mask >>= 1)
		if (mask & 1)
			buf[i] = set_char;
}

void ts_format(char *buf, uint8_t dl_mask, uint8_t ul_mask)
{
	snprintf(buf, 9, OSMO_BIT_SPEC, OSMO_BIT_PRINT_EX(dl_mask, 'D'));
	masked_override_with(buf, ul_mask, 'U');
	masked_override_with(buf, ul_mask & dl_mask, 'C');
}

uint16_t mslot_wrap_window(uint16_t win)
{
	return (win | win >> 8) & 0xFF;
}

bool mslot_test_and_set_bit(uint32_t *bits, size_t elem)
{
	bool was_set = bits[elem/32] & (1 << (elem % 32));
	bits[elem/32] |= (1 << (elem % 32));

	return was_set;
}

/*! Filter out bad slots
 *
 *  \param[in] mask TS selection mask
 *  \param[in] ul_slots set of UL timeslots
 *  \param[in] dl_slots set of DL timeslots
 *  \param[in] rx_valid_win Mask for valid RX window value
 *  \returns negative error code or RX window on success
 */
int16_t mslot_filter_bad(uint8_t mask, uint8_t ul_slots, uint8_t dl_slots, uint16_t rx_valid_win)
{
	uint8_t rx_good;
	uint16_t rx_bad = (uint16_t)(0xFF & ~mask) << ul_slots;

	/* TODO: CHECK this calculation -> separate function for unit testing */
	rx_bad = (rx_bad | (rx_bad >> 8)) & 0xFF;
	rx_good = dl_slots & ~rx_bad;
	if (!rx_good)
		return -1;

	return rx_good & rx_valid_win;
}