2 * Copyright (c) 1997, 2000 Hellmuth Michaelis. All rights reserved.
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
13 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
14 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
17 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 *---------------------------------------------------------------------------
27 * i4b_iframe.c - i frame handling routines
28 * ------------------------------------------
30 * $Id: i4b_iframe.c,v 1.25 2000/08/24 11:48:57 hm Exp $
32 * $FreeBSD: src/sys/i4b/layer2/i4b_iframe.c,v 1.6.2.1 2001/08/10 14:08:41 obrien Exp $
33 * $DragonFly: src/sys/net/i4b/layer2/i4b_iframe.c,v 1.7 2005/06/14 21:19:19 joerg Exp $
35 * last edit-date: [Thu Aug 24 12:49:18 2000]
37 *---------------------------------------------------------------------------*/
39 #include "use_i4bq921.h"
42 #include <sys/param.h>
43 #include <sys/kernel.h>
44 #include <sys/systm.h>
46 #include <sys/socket.h>
47 #include <sys/thread2.h>
50 #include <net/i4b/include/machine/i4b_debug.h>
51 #include <net/i4b/include/machine/i4b_trace.h>
53 #include "../include/i4b_global.h"
54 #include "../include/i4b_l1l2.h"
55 #include "../include/i4b_l2l3.h"
56 #include "../include/i4b_mbuf.h"
59 #include "i4b_l2fsm.h"
61 /*---------------------------------------------------------------------------*
63 * implements the routine "I COMMAND" Q.921 03/93 pp 68 and pp 77
64 *---------------------------------------------------------------------------*/
66 i4b_rxd_i_frame(int unit, struct mbuf *m)
68 l2_softc_t *l2sc = &l2_softc[unit];
69 u_char *ptr = m->m_data;
75 if(!((l2sc->tei_valid == TEI_VALID) &&
76 (l2sc->tei == GETTEI(*(ptr+OFF_TEI)))))
82 if((l2sc->Q921_state != ST_MULTIFR) && (l2sc->Q921_state != ST_TIMREC))
85 NDBGL2(L2_I_ERR, "ERROR, state != (MF || TR)!");
91 l2sc->stat.rx_i++; /* update frame count */
93 nr = GETINR(*(ptr + OFF_INR));
94 ns = GETINS(*(ptr + OFF_INS));
95 p = GETIP(*(ptr + OFF_INR));
97 i4b_rxd_ack(l2sc, nr); /* last packet ack */
99 if(l2sc->own_busy) /* own receiver busy ? */
101 i4b_Dfreembuf(m); /* yes, discard information */
103 if(p == 1) /* P bit == 1 ? */
105 i4b_tx_rnr_response(l2sc, p); /* yes, tx RNR */
106 l2sc->ack_pend = 0; /* clear ACK pending */
109 else /* own receiver ready */
111 if(ns == l2sc->vr) /* expected sequence number ? */
113 M128INC(l2sc->vr); /* yes, update */
115 l2sc->rej_excpt = 0; /* clr reject exception */
117 m_adj(m, I_HDR_LEN); /* strip i frame header */
119 l2sc->iframe_sent = 0; /* reset i acked already */
121 DL_Data_Ind(l2sc->unit, m); /* pass data up */
123 if(!l2sc->iframe_sent)
125 i4b_tx_rr_response(l2sc, p); /* yes, tx RR */
126 l2sc->ack_pend = 0; /* clr ACK pending */
129 else /* ERROR, sequence number NOT expected */
131 i4b_Dfreembuf(m); /* discard information */
133 if(l2sc->rej_excpt == 1) /* already exception ? */
135 if(p == 1) /* immediate response ? */
137 i4b_tx_rr_response(l2sc, p); /* yes, tx RR */
138 l2sc->ack_pend = 0; /* clr ack pend */
141 else /* not in exception cond */
143 l2sc->rej_excpt = 1; /* set exception */
144 i4b_tx_rej_response(l2sc, p); /* tx REJ */
145 l2sc->ack_pend = 0; /* clr ack pending */
150 /* sequence number ranges as expected ? */
152 if(i4b_l2_nr_ok(nr, l2sc->va, l2sc->vs))
154 if(l2sc->Q921_state == ST_TIMREC)
163 if(l2sc->peer_busy) /* yes, other side busy ? */
165 l2sc->va = nr; /* yes, update ack count */
167 else /* other side ready */
169 if(nr == l2sc->vs) /* count expected ? */
171 l2sc->va = nr; /* update ack */
173 i4b_T203_restart(l2sc);
180 i4b_T200_restart(l2sc);
187 i4b_nr_error_recovery(l2sc); /* sequence error */
188 l2sc->Q921_state = ST_AW_EST;
194 /*---------------------------------------------------------------------------*
195 * internal I FRAME QUEUED UP routine (Q.921 03/93 p 61)
196 *---------------------------------------------------------------------------*/
198 i4b_i_frame_queued_up(l2_softc_t *l2sc)
206 if((l2sc->peer_busy) || (l2sc->vs == ((l2sc->va + MAX_K_VALUE) & 127)))
210 NDBGL2(L2_I_MSG, "regen IFQUP, cause: peer busy!");
213 if(l2sc->vs == ((l2sc->va + MAX_K_VALUE) & 127))
215 NDBGL2(L2_I_MSG, "regen IFQUP, cause: vs=va+k!");
219 * XXX see: Q.921, page 36, 5.6.1 ".. may retransmit an I
220 * frame ...", shall we retransmit the last i frame ?
223 if(!(IF_QEMPTY(&l2sc->i_queue)))
225 NDBGL2(L2_I_MSG, "re-scheduling IFQU call!");
226 callout_reset(&l2sc->IFQU_timeout, IFQU_DLY,
227 (void *)i4b_i_frame_queued_up, l2sc);
233 IF_DEQUEUE(&l2sc->i_queue, m); /* fetch next frame to tx */
237 NDBGL2(L2_I_ERR, "ERROR, mbuf NULL after IF_DEQUEUE");
244 PUTSAPI(SAPI_CCP, CR_CMD_TO_NT, *(ptr + OFF_SAPI));
245 PUTTEI(l2sc->tei, *(ptr + OFF_TEI));
247 *(ptr + OFF_INS) = (l2sc->vs << 1) & 0xfe; /* bit 0 = 0 */
248 *(ptr + OFF_INR) = (l2sc->vr << 1) & 0xfe; /* P bit = 0 */
250 l2sc->stat.tx_i++; /* update frame counter */
252 PH_Data_Req(l2sc->unit, m, MBUF_DONTFREE); /* free'd when ack'd ! */
254 l2sc->iframe_sent = 1; /* in case we ack an I frame with another I frame */
256 if(l2sc->ua_num != UA_EMPTY) /* failsafe */
258 NDBGL2(L2_I_ERR, "ERROR, l2sc->ua_num: %d != UA_EMPTY", l2sc->ua_num);
259 i4b_print_l2var(l2sc);
260 i4b_Dfreembuf(l2sc->ua_frame);
263 l2sc->ua_frame = m; /* save unacked frame */
264 l2sc->ua_num = l2sc->vs; /* save frame number */
272 if(l2sc->T200 == TIMER_IDLE)
275 i4b_T200_start(l2sc);
279 #endif /* NI4BQ921 > 0 */