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/*! \defgroup gsm0502 GSM 05.02 / 3GPP TS 45.002
* @{
* \file gsm0502.h
*/
#pragma once
#include <stdint.h>
#include <osmocom/gsm/protocol/gsm_04_08.h>
#include <osmocom/gsm/protocol/gsm_08_58.h>
/* 4.3.3 TDMA frame number : constants and modular arithmetic */
#define GSM_TDMA_FN_DURATION_nS 4615384 /* in 1e−9 seconds (approx) */
#define GSM_TDMA_FN_DURATION_uS 4615 /* in 1e-6 seconds (approx) */
#define GSM_TDMA_SUPERFRAME (26 * 51)
#define GSM_TDMA_HYPERFRAME (2048 * GSM_TDMA_SUPERFRAME)
/*! Return the sum of two specified TDMA frame numbers (summation) */
#define GSM_TDMA_FN_SUM(a, b) \
(((a) + (b)) % GSM_TDMA_HYPERFRAME)
/*! Return the difference of two specified TDMA frame numbers (subtraction) */
#define GSM_TDMA_FN_SUB(a, b) \
(((a) + GSM_TDMA_HYPERFRAME - (b)) % GSM_TDMA_HYPERFRAME)
/*! Return the *minimum* difference of two specified TDMA frame numbers (distance) */
#define GSM_TDMA_FN_DIFF(a, b) \
OSMO_MIN(GSM_TDMA_FN_SUB(a, b), GSM_TDMA_FN_SUB(b, a))
/*! Increment the given TDMA frame number by 1 and return the result (like ++fn) */
#define GSM_TDMA_FN_INC(fn) \
((fn) = GSM_TDMA_FN_SUM((fn), 1))
/*! Decrement the given TDMA frame number by 1 and return the result (like --fn) */
#define GSM_TDMA_FN_DEC(fn) \
((fn) = GSM_TDMA_FN_SUB((fn), 1))
/* 5.2.3.1 Normal burst for GMSK (1 bit per symbol) */
#define GSM_NBITS_NB_GMSK_TAIL 3
#define GSM_NBITS_NB_GMSK_PAYLOAD (2 * 58)
#define GSM_NBITS_NB_GMSK_TRAIN_SEQ 26
#define GSM_NBITS_NB_GMSK_BURST 148 /* without guard period */
/* 5.2.3.3 Normal burst for 8-PSK (3 bits per symbol) */
#define GSM_NBITS_NB_8PSK_TAIL (GSM_NBITS_NB_GMSK_TAIL * 3)
#define GSM_NBITS_NB_8PSK_PAYLOAD (GSM_NBITS_NB_GMSK_PAYLOAD * 3)
#define GSM_NBITS_NB_8PSK_TRAIN_SEQ (GSM_NBITS_NB_GMSK_TRAIN_SEQ * 3)
#define GSM_NBITS_NB_8PSK_BURST (GSM_NBITS_NB_GMSK_BURST * 3)
/* 5.2.5 Synchronization burst (also GMSK) */
#define GSM_NBITS_SB_GMSK_TAIL GSM_NBITS_NB_GMSK_TAIL
#define GSM_NBITS_SB_GMSK_PAYLOAD (2 * 39)
#define GSM_NBITS_SB_GMSK_ETRAIN_SEQ 64
#define GSM_NBITS_SB_GMSK_BURST GSM_NBITS_NB_GMSK_BURST
/* 5.2.6 Dummy burst (also GMSK) */
#define GSM_NBITS_DB_GMSK_TAIL GSM_NBITS_NB_GMSK_TAIL
#define GSM_NBITS_DB_GMSK_MIXED 142
#define GSM_NBITS_DB_GMSK_BURST GSM_NBITS_NB_GMSK_BURST
/* 5.2.7 Access burst (also GMSK) */
#define GSM_NBITS_AB_GMSK_ETAIL 8
#define GSM_NBITS_AB_GMSK_SYNCH_SEQ 41
#define GSM_NBITS_AB_GMSK_PAYLOAD 36
#define GSM_NBITS_AB_GMSK_TAIL GSM_NBITS_NB_GMSK_TAIL
#define GSM_NBITS_AB_GMSK_BURST GSM_NBITS_NB_GMSK_BURST
/*! Compare the given TDMA FNs, taking the wrapping into account.
* \param[in] fn1 First TDMA Fn value to compare.
* \param[in] fn2 Second TDMA Fn value to compare.
* \returns similarly to memcmp(), -1 if fn1 goes before fn2;
* 0 if fn1 equals fn2;
* 1 if fn1 goes after fn2. */
static inline int gsm0502_fncmp(uint32_t fn1, uint32_t fn2)
{
const uint32_t thresh = GSM_TDMA_HYPERFRAME / 2;
if (fn1 == fn2)
return 0;
if ((fn1 < fn2 && (fn2 - fn1) < thresh) ||
(fn1 > fn2 && (fn1 - fn2) > thresh))
return -1;
return 1;
}
/* Table 5 Clause 7 TS 05.02 */
static inline unsigned int
gsm0502_get_n_pag_blocks(const struct gsm48_control_channel_descr *chan_desc)
{
if (chan_desc->ccch_conf == RSL_BCCH_CCCH_CONF_1_C)
return 3 - chan_desc->bs_ag_blks_res;
else
return 9 - chan_desc->bs_ag_blks_res;
}
/* Chapter 6.5.2 of TS 05.02 */
static inline unsigned int
gsm0502_get_ccch_group(uint64_t imsi, unsigned int bs_cc_chans,
unsigned int n_pag_blocks)
{
return (imsi % 1000) % (bs_cc_chans * n_pag_blocks) / n_pag_blocks;
}
/* Chapter 6.5.2 of TS 05.02 */
static inline unsigned int
gsm0502_get_paging_group(uint64_t imsi, unsigned int bs_cc_chans,
int n_pag_blocks)
{
return (imsi % 1000) % (bs_cc_chans * n_pag_blocks) % n_pag_blocks;
}
unsigned int
gsm0502_calc_paging_group(const struct gsm48_control_channel_descr *chan_desc, uint64_t imsi);
enum gsm0502_fn_remap_channel {
FN_REMAP_TCH_F,
FN_REMAP_TCH_H0,
FN_REMAP_TCH_H1,
FN_REMAP_FACCH_F,
FN_REMAP_FACCH_H0,
FN_REMAP_FACCH_H1,
FN_REMAP_MAX,
};
uint32_t gsm0502_fn_remap(uint32_t fn, enum gsm0502_fn_remap_channel channel);
uint16_t gsm0502_hop_seq_gen(const struct gsm_time *t,
uint8_t hsn, uint8_t maio,
size_t n, const uint16_t *ma);
int gsm0502_fn2ccch_block(uint32_t fn);
/*! @} */
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