encoding: pass pdch slot directly to encoding functions

In order to be able to encode frequency hopping parameters, let's
pass a const pointer to 'gprs_rlcmac_pdch' (PDCH slot) directly,
instead of passing all related parameters separately.

Change-Id: I6bccad508f0fdccc4a763211008dd847a9111a8d
Related: SYS#4868, OS#4547

4 files changed, 34 insertions, 21 deletions

diff --git a/src/bts.cpp b/src/bts.cpp
index 76ca1b02..5cd2b1d9 100644
--- a/src/bts.cpp
+++ b/src/bts.cpp
@@ -899,8 +899,9 @@ send_imm_ass_rej:
 		     trx_no, m_bts.trx[trx_no].arfcn & ~ARFCN_FLAG_MASK,
 		     ts_no, ta, tsc, tbf ? tbf->tfi() : -1, usf);
 		plen = Encoding::write_immediate_assignment(
-			tbf, bv, false, rip->ra, Fn, ta, m_bts.trx[trx_no].arfcn,
-			ts_no, tsc, usf, false, sb_fn, m_bts.alpha, m_bts.gamma, -1,
+			&m_bts.trx[trx_no].pdch[ts_no], tbf, bv,
+			false, rip->ra, Fn, ta, usf, false, sb_fn,
+			m_bts.alpha, m_bts.gamma, -1,
 			rip->burst_type);
 		do_rate_ctr_inc(CTR_IMMEDIATE_ASSIGN_UL_TBF);
 	}
@@ -967,8 +968,9 @@ int BTS::rcv_ptcch_rach(const struct rach_ind_params *rip)
 
 void BTS::snd_dl_ass(gprs_rlcmac_tbf *tbf, bool poll, uint16_t pgroup)
 {
+	uint8_t trx_no = tbf->trx->trx_no;
+	uint8_t ts_no = tbf->first_ts;
 	int plen;
-	unsigned int ts = tbf->first_ts;
 
 	LOGPTBF(tbf, LOGL_INFO, "TX: START Immediate Assignment Downlink (PCH)\n");
 	bitvec *immediate_assignment = bitvec_alloc(22, tall_pcu_ctx); /* without plen */
@@ -976,12 +978,12 @@ void BTS::snd_dl_ass(gprs_rlcmac_tbf *tbf, bool poll, uint16_t pgroup)
 	/* use request reference that has maximum distance to current time,
 	 * so the assignment will not conflict with possible RACH requests. */
 	LOGP(DRLCMAC, LOGL_DEBUG, " - TRX=%d (%d) TS=%d TA=%d pollFN=%d\n",
-		tbf->trx->trx_no, tbf->trx->arfcn,
-		ts, tbf->ta(), poll ? tbf->poll_fn : -1);
-	plen = Encoding::write_immediate_assignment(tbf, immediate_assignment, true, 125,
-						    (tbf->pdch[ts]->last_rts_fn + 21216) % GSM_MAX_FN, tbf->ta(),
-						    tbf->trx->arfcn, ts, tbf->tsc(), 7, poll,
-						    tbf->poll_fn, m_bts.alpha, m_bts.gamma, -1,
+		trx_no, tbf->trx->arfcn, ts_no, tbf->ta(), poll ? tbf->poll_fn : -1);
+	plen = Encoding::write_immediate_assignment(&m_bts.trx[trx_no].pdch[ts_no],
+						    tbf, immediate_assignment, true, 125,
+						    (tbf->pdch[ts_no]->last_rts_fn + 21216) % GSM_MAX_FN,
+						    tbf->ta(), 7, poll, tbf->poll_fn,
+						    m_bts.alpha, m_bts.gamma, -1,
 						    GSM_L1_BURST_TYPE_ACCESS_0);
 	if (plen >= 0) {
 		do_rate_ctr_inc(CTR_IMMEDIATE_ASSIGN_DL_TBF);
diff --git a/src/encoding.cpp b/src/encoding.cpp
index 15de6d75..76a1cecb 100644
--- a/src/encoding.cpp
+++ b/src/encoding.cpp
@@ -439,9 +439,10 @@ int Encoding::write_immediate_assignment_reject(
  * see GSM 04.08, 9.1.18 and GSM 44.018, 9.1.18 + 10.5.2.16
  */
 int Encoding::write_immediate_assignment(
+	const struct gprs_rlcmac_pdch *pdch,
 	struct gprs_rlcmac_tbf *tbf,
 	bitvec * dest, bool downlink, uint16_t ra,
-	uint32_t ref_fn, uint8_t ta, uint16_t arfcn, uint8_t ts, uint8_t tsc,
+	uint32_t ref_fn, uint8_t ta,
 	uint8_t usf, bool polling, uint32_t fn, uint8_t alpha,
 	uint8_t gamma, int8_t ta_idx, enum ph_burst_type burst_type)
 {
@@ -462,11 +463,12 @@ int Encoding::write_immediate_assignment(
 	bitvec_write_field(dest, &wp,0x0,4); // Page Mode
 
 	// GSM 04.08 10.5.2.25a Packet Channel Description
-	bitvec_write_field(dest, &wp,0x1,5);                               // Channel type
-	bitvec_write_field(dest, &wp,ts,3);     // TN
-	bitvec_write_field(dest, &wp,tsc,3);    // TSC
-	bitvec_write_field(dest, &wp,0x0,3);                               // non-hopping RF channel configuraion
-	bitvec_write_field(dest, &wp,arfcn,10); // ARFCN
+	bitvec_write_field(dest, &wp, 0x01, 5);			// Channel type
+	bitvec_write_field(dest, &wp, pdch->ts_no, 3);		// TN
+	bitvec_write_field(dest, &wp, pdch->tsc, 3);		// TSC
+
+	bitvec_write_field(dest, &wp, 0x00, 3);			// spare (non-hopping RF channel configuraion)
+	bitvec_write_field(dest, &wp, pdch->trx->arfcn, 10);	// ARFCN
 
 	//10.5.2.30 Request Reference
 	if (((burst_type == GSM_L1_BURST_TYPE_ACCESS_1) ||
diff --git a/src/encoding.h b/src/encoding.h
index a5566878..18392f75 100644
--- a/src/encoding.h
+++ b/src/encoding.h
@@ -42,10 +42,11 @@ struct gprs_rlc_data_block_info;
 class Encoding {
 public:
 	static int write_immediate_assignment(
+			const struct gprs_rlcmac_pdch *pdch,
 			struct gprs_rlcmac_tbf *tbf,
 			bitvec * dest, bool downlink, uint16_t ra,
-			uint32_t ref_fn, uint8_t ta, uint16_t arfcn, uint8_t ts,
-			uint8_t tsc, uint8_t usf, bool polling,
+			uint32_t ref_fn, uint8_t ta,
+			uint8_t usf, bool polling,
 			uint32_t fn, uint8_t alpha, uint8_t gamma,
 			int8_t ta_idx,
 			enum ph_burst_type burst_type);
diff --git a/tests/types/TypesTest.cpp b/tests/types/TypesTest.cpp
index e1c894dd..353d8212 100644
--- a/tests/types/TypesTest.cpp
+++ b/tests/types/TypesTest.cpp
@@ -728,17 +728,25 @@ static void test_egprs_ul_ack_nack()
 static void check_imm_ass(struct gprs_rlcmac_tbf *tbf, bool dl, enum ph_burst_type bt, const uint8_t *exp, uint8_t len,
 			  const char *kind)
 {
-	uint8_t alpha = 7, gamma = 8, ta = 35, ts = 5, tsc = 1, usf = 1, sz = sizeof(DUMMY_VEC) / 2, plen;
+	uint8_t alpha = 7, gamma = 8, ta = 35, usf = 1, sz = sizeof(DUMMY_VEC) / 2, plen;
 	bitvec *immediate_assignment = bitvec_alloc(sz, tall_pcu_ctx);
 	struct msgb *m = msgb_alloc(80, "test");
 	bool poll = true;
-	uint16_t ra = 13, arfcn = 877;
+	uint16_t ra = 13;
 	uint32_t ref_fn = 24, fn = 11;
 	int8_t ta_idx = 0;
 
+	/* HACK: tbf can be NULL, so we cannot use tbf->trx here */
+	struct gprs_rlcmac_trx trx = { };
+	trx.pdch[5].trx = &trx;
+	trx.pdch[5].ts_no = 5;
+	trx.pdch[5].tsc = 1;
+	trx.arfcn = 877;
+
 	bitvec_unhex(immediate_assignment, DUMMY_VEC);
-	plen = Encoding::write_immediate_assignment(tbf, immediate_assignment, dl,
-						    ra, ref_fn, ta, arfcn, ts, tsc, usf,
+	plen = Encoding::write_immediate_assignment(&trx.pdch[5], tbf,
+						    immediate_assignment,
+						    dl, ra, ref_fn, ta, usf,
 						    poll, fn, alpha, gamma, ta_idx, bt);
 	printf("[%u] %s Immediate Assignment <%s>:\n\t%s\n", plen, dl ? "DL" : "UL", kind,
 	       osmo_hexdump(immediate_assignment->data, sz));