contiki/core/net/mac/contikimac.c

1230 lines
37 KiB
C

/*
* Copyright (c) 2010, Swedish Institute of Computer Science.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the Institute nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* This file is part of the Contiki operating system.
*
* $Id: contikimac.c,v 1.48 2011/01/25 14:29:46 adamdunkels Exp $
*/
/**
* \file
* The Contiki power-saving MAC protocol (ContikiMAC)
* \author
* Adam Dunkels <adam@sics.se>
* Niclas Finne <nfi@sics.se>
* Joakim Eriksson <joakime@sics.se>
*/
#include "net/netstack.h"
#include "dev/leds.h"
#include "dev/radio.h"
#include "dev/watchdog.h"
#include "lib/random.h"
#include "net/mac/contikimac.h"
#include "net/rime.h"
#include "sys/compower.h"
#include "sys/pt.h"
#include "sys/rtimer.h"
/*#include "cooja-debug.h"*/
#include "contiki-conf.h"
#ifdef EXPERIMENT_SETUP
#include "experiment-setup.h"
#endif
#include <string.h>
#ifndef WITH_PHASE_OPTIMIZATION
#define WITH_PHASE_OPTIMIZATION 1
#endif
#ifndef WITH_STREAMING
#define WITH_STREAMING 0
#endif
#ifndef WITH_CONTIKIMAC_HEADER
#define WITH_CONTIKIMAC_HEADER 1
#endif
#ifndef WITH_FAST_SLEEP
#define WITH_FAST_SLEEP 1
#endif
#if NETSTACK_RDC_CHANNEL_CHECK_RATE >= 64
#undef WITH_PHASE_OPTIMIZATION
#define WITH_PHASE_OPTIMIZATION 0
#endif
struct announcement_data {
uint16_t id;
uint16_t value;
};
/* The maximum number of announcements in a single announcement
message - may need to be increased in the future. */
#define ANNOUNCEMENT_MAX 10
#if WITH_CONTIKIMAC_HEADER
#define CONTIKIMAC_ID 0x00
struct hdr {
uint8_t id;
uint8_t len;
};
#endif /* WITH_CONTIKIMAC_HEADER */
/* The structure of the announcement messages. */
struct announcement_msg {
uint8_t announcement_magic[2];
uint16_t num;
struct announcement_data data[ANNOUNCEMENT_MAX];
};
#define ANNOUNCEMENT_MAGIC1 0xAD
#define ANNOUNCEMENT_MAGIC2 0xAD
/* The length of the header of the announcement message, i.e., the
"num" field in the struct. */
#define ANNOUNCEMENT_MSG_HEADERLEN (sizeof(uint16_t) * 2)
#ifdef CONTIKIMAC_CONF_CYCLE_TIME
#define CYCLE_TIME (CONTIKIMAC_CONF_CYCLE_TIME)
#else
#define CYCLE_TIME (RTIMER_ARCH_SECOND / NETSTACK_RDC_CHANNEL_CHECK_RATE)
#endif
/* ContikiMAC performs periodic channel checks. Each channel check
consists of two or more CCA checks. CCA_COUNT_MAX is the number of
CCAs to be done for each periodic channel check. The default is
two.*/
#define CCA_COUNT_MAX 2
/* CCA_CHECK_TIME is the time it takes to perform a CCA check. */
#define CCA_CHECK_TIME RTIMER_ARCH_SECOND / 8192
/* CCA_SLEEP_TIME is the time between two successive CCA checks. */
#define CCA_SLEEP_TIME RTIMER_ARCH_SECOND / 2000
/* CHECK_TIME is the total time it takes to perform CCA_COUNT_MAX
CCAs. */
#define CHECK_TIME (CCA_COUNT_MAX * (CCA_CHECK_TIME + CCA_SLEEP_TIME))
/* LISTEN_TIME_AFTER_PACKET_DETECTED is the time that we keep checking
for activity after a potential packet has been detected by a CCA
check. */
#define LISTEN_TIME_AFTER_PACKET_DETECTED RTIMER_ARCH_SECOND / 80
/* MAX_SILENCE_PERIODS is the maximum amount of periods (a period is
CCA_CHECK_TIME + CCA_SLEEP_TIME) that we allow to be silent before
we turn of the radio. */
#define MAX_SILENCE_PERIODS 5
/* MAX_NONACTIVITY_PERIODS is the maximum number of periods we allow
the radio to be turned on without any packet being received, when
WITH_FAST_SLEEP is enabled. */
#define MAX_NONACTIVITY_PERIODS 10
/* STROBE_TIME is the maximum amount of time a transmitted packet
should be repeatedly transmitted as part of a transmission. */
#define STROBE_TIME (CYCLE_TIME + 2 * CHECK_TIME)
/* GUARD_TIME is the time before the expected phase of a neighbor that
a transmitted should begin transmitting packets. */
#define GUARD_TIME 11 * CHECK_TIME
/* INTER_PACKET_INTERVAL is the interval between two successive packet transmissions */
#define INTER_PACKET_INTERVAL RTIMER_ARCH_SECOND / 5000
/* AFTER_ACK_DETECTECT_WAIT_TIME is the time to wait after a potential
ACK packet has been detected until we can read it out from the
radio. */
#define AFTER_ACK_DETECTECT_WAIT_TIME RTIMER_ARCH_SECOND / 1500
/* MAX_PHASE_STROBE_TIME is the time that we transmit repeated packets
to a neighbor for which we have a phase lock. */
#define MAX_PHASE_STROBE_TIME RTIMER_ARCH_SECOND / 60
/* SHORTEST_PACKET_SIZE is the shortest packet that ContikiMAC
allows. Packets have to be a certain size to be able to be detected
by two consecutive CCA checks, and here is where we define this
shortest size. */
#define SHORTEST_PACKET_SIZE 43
/* The cycle time for announcements. */
#ifdef ANNOUNCEMENT_CONF_PERIOD
#define ANNOUNCEMENT_PERIOD ANNOUNCEMENT_CONF_PERIOD
#else /* ANNOUNCEMENT_CONF_PERIOD */
#define ANNOUNCEMENT_PERIOD 1 * CLOCK_SECOND
#endif /* ANNOUNCEMENT_CONF_PERIOD */
/* The time before sending an announcement within one announcement
cycle. */
#define ANNOUNCEMENT_TIME (random_rand() % (ANNOUNCEMENT_PERIOD))
#define ACK_LEN 3
#include <stdio.h>
static struct rtimer rt;
static struct pt pt;
static volatile uint8_t contikimac_is_on = 0;
static volatile uint8_t contikimac_keep_radio_on = 0;
static volatile unsigned char we_are_sending = 0;
static volatile unsigned char radio_is_on = 0;
#define DEBUG 0
#if DEBUG
#include <stdio.h>
#define PRINTF(...) printf(__VA_ARGS__)
#define PRINTDEBUG(...) printf(__VA_ARGS__)
#else
#define PRINTF(...)
#define PRINTDEBUG(...)
#endif
#if CONTIKIMAC_CONF_ANNOUNCEMENTS
/* Timers for keeping track of when to send announcements. */
static struct ctimer announcement_cycle_ctimer, announcement_ctimer;
static int announcement_radio_txpower;
#endif /* CONTIKIMAC_CONF_ANNOUNCEMENTS */
/* Flag that is used to keep track of whether or not we are snooping
for announcements from neighbors. */
static volatile uint8_t is_snooping;
#if CONTIKIMAC_CONF_COMPOWER
static struct compower_activity current_packet;
#endif /* CONTIKIMAC_CONF_COMPOWER */
#if WITH_PHASE_OPTIMIZATION
#include "net/mac/phase.h"
#ifndef MAX_PHASE_NEIGHBORS
#define MAX_PHASE_NEIGHBORS 30
#endif
PHASE_LIST(phase_list, MAX_PHASE_NEIGHBORS);
#endif /* WITH_PHASE_OPTIMIZATION */
static volatile uint8_t is_streaming;
static rimeaddr_t is_streaming_to, is_streaming_to_too;
static volatile rtimer_clock_t stream_until;
#define DEFAULT_STREAM_TIME (1 * CYCLE_TIME)
#ifndef MIN
#define MIN(a, b) ((a) < (b)? (a) : (b))
#endif /* MIN */
struct seqno {
rimeaddr_t sender;
uint8_t seqno;
};
#define MAX_SEQNOS 8
static struct seqno received_seqnos[MAX_SEQNOS];
#if CONTIKIMAC_CONF_BROADCAST_RATE_LIMIT
static struct timer broadcast_rate_timer;
static int broadcast_rate_counter;
#endif /* CONTIKIMAC_CONF_BROADCAST_RATE_LIMIT */
/*---------------------------------------------------------------------------*/
static void
on(void)
{
if(contikimac_is_on && radio_is_on == 0) {
radio_is_on = 1;
NETSTACK_RADIO.on();
}
}
/*---------------------------------------------------------------------------*/
static void
off(void)
{
if(contikimac_is_on && radio_is_on != 0 && /*is_streaming == 0 &&*/
contikimac_keep_radio_on == 0
/* && is_snooping == 0*/) {
radio_is_on = 0;
NETSTACK_RADIO.off();
}
}
/*---------------------------------------------------------------------------*/
static volatile rtimer_clock_t cycle_start;
static char powercycle(struct rtimer *t, void *ptr);
static void
schedule_powercycle(struct rtimer *t, rtimer_clock_t time)
{
int r;
if(contikimac_is_on) {
if(RTIMER_CLOCK_LT(RTIMER_TIME(t) + time, RTIMER_NOW() + 2)) {
time = RTIMER_NOW() - RTIMER_TIME(t) + 2;
}
#if NURTIMER
r = rtimer_reschedule(t, time, 1);
#else
r = rtimer_set(t, RTIMER_TIME(t) + time, 1,
(void (*)(struct rtimer *, void *))powercycle, NULL);
#endif
if(r != RTIMER_OK) {
printf("schedule_powercycle: could not set rtimer\n");
}
}
}
static void
schedule_powercycle_fixed(struct rtimer *t, rtimer_clock_t fixed_time)
{
int r;
if(contikimac_is_on) {
if(RTIMER_CLOCK_LT(fixed_time, RTIMER_NOW() + 1)) {
fixed_time = RTIMER_NOW() + 1;
}
#if NURTIMER
r = rtimer_reschedule(t, RTIMER_TIME(t) - time, 1);
#else
r = rtimer_set(t, fixed_time, 1,
(void (*)(struct rtimer *, void *))powercycle, NULL);
#endif
if(r != RTIMER_OK) {
printf("schedule_powercycle: could not set rtimer\n");
}
}
}
static void
powercycle_turn_radio_off(void)
{
if(we_are_sending == 0) {
off();
}
}
static void
powercycle_turn_radio_on(void)
{
if(we_are_sending == 0) {
on();
}
}
static char
powercycle(struct rtimer *t, void *ptr)
{
PT_BEGIN(&pt);
cycle_start = RTIMER_NOW();
while(1) {
static uint8_t packet_seen;
static rtimer_clock_t t0;
static uint8_t count;
cycle_start += CYCLE_TIME;
if(WITH_STREAMING && is_streaming) {
#if NURTIMER
if(!RTIMER_CLOCK_LT(cycle_start, RTIMER_NOW(), stream_until))
#else
if(!RTIMER_CLOCK_LT(RTIMER_NOW(), stream_until))
#endif
{
is_streaming = 0;
rimeaddr_copy(&is_streaming_to, &rimeaddr_null);
rimeaddr_copy(&is_streaming_to_too, &rimeaddr_null);
}
}
packet_seen = 0;
do {
for(count = 0; count < CCA_COUNT_MAX; ++count) {
t0 = RTIMER_NOW();
if(we_are_sending == 0) {
powercycle_turn_radio_on();
// schedule_powercycle_fixed(t, t0 + CCA_CHECK_TIME);
#if 0
#if NURTIMER
while(RTIMER_CLOCK_LT(t0, RTIMER_NOW(), t0 + CCA_CHECK_TIME));
#else
while(RTIMER_CLOCK_LT(RTIMER_NOW(), t0 + CCA_CHECK_TIME));
#endif
#endif /* 0 */
/* Check if a packet is seen in the air. If so, we keep the
radio on for a while (LISTEN_TIME_AFTER_PACKET_DETECTED) to
be able to receive the packet. We also continuously check
the radio medium to make sure that we wasn't woken up by a
false positive: a spurious radio interference that was not
caused by an incoming packet. */
if(NETSTACK_RADIO.channel_clear() == 0) {
packet_seen = 1;
break;
}
powercycle_turn_radio_off();
}
// schedule_powercycle_fixed(t, t0 + CCA_CHECK_TIME + CCA_SLEEP_TIME);
schedule_powercycle_fixed(t, RTIMER_NOW() + CCA_SLEEP_TIME);
/* COOJA_DEBUG_STR("yield\n");*/
PT_YIELD(&pt);
}
if(packet_seen) {
static rtimer_clock_t start;
static uint8_t silence_periods, periods;
start = RTIMER_NOW();
periods = silence_periods = 0;
while(we_are_sending == 0 && radio_is_on &&
RTIMER_CLOCK_LT(RTIMER_NOW(),
(start + LISTEN_TIME_AFTER_PACKET_DETECTED))) {
/* Check for a number of consecutive periods of
non-activity. If we see two such periods, we turn the
radio off. Also, if a packet has been successfully
received (as indicated by the
NETSTACK_RADIO.pending_packet() function), we stop
snooping. */
if(NETSTACK_RADIO.channel_clear()) {
++silence_periods;
} else {
silence_periods = 0;
}
++periods;
if(NETSTACK_RADIO.receiving_packet()) {
silence_periods = 0;
}
if(silence_periods > MAX_SILENCE_PERIODS) {
powercycle_turn_radio_off();
#if CONTIKIMAC_CONF_COMPOWER
compower_accumulate(&compower_idle_activity);
#endif /* CONTIKIMAC_CONF_COMPOWER */
break;
}
if(WITH_FAST_SLEEP &&
periods > MAX_NONACTIVITY_PERIODS &&
!(NETSTACK_RADIO.receiving_packet() ||
NETSTACK_RADIO.pending_packet())) {
powercycle_turn_radio_off();
#if CONTIKIMAC_CONF_COMPOWER
compower_accumulate(&compower_idle_activity);
#endif /* CONTIKIMAC_CONF_COMPOWER */
break;
}
if(NETSTACK_RADIO.pending_packet()) {
break;
}
schedule_powercycle(t, CCA_CHECK_TIME + CCA_SLEEP_TIME);
PT_YIELD(&pt);
}
if(radio_is_on) {
if(!(NETSTACK_RADIO.receiving_packet() ||
NETSTACK_RADIO.pending_packet()) ||
!RTIMER_CLOCK_LT(RTIMER_NOW(),
(start + LISTEN_TIME_AFTER_PACKET_DETECTED))) {
powercycle_turn_radio_off();
#if CONTIKIMAC_CONF_COMPOWER
compower_accumulate(&compower_idle_activity);
#endif /* CONTIKIMAC_CONF_COMPOWER */
}
}
} else {
#if CONTIKIMAC_CONF_COMPOWER
compower_accumulate(&compower_idle_activity);
#endif /* CONTIKIMAC_CONF_COMPOWER */
}
} while((is_snooping || is_streaming) &&
RTIMER_CLOCK_LT(RTIMER_NOW() - cycle_start, CYCLE_TIME - CHECK_TIME));
if(RTIMER_CLOCK_LT(RTIMER_NOW() - cycle_start, CYCLE_TIME)) {
/* schedule_powercycle(t, CYCLE_TIME - (RTIMER_NOW() - cycle_start));*/
schedule_powercycle_fixed(t, CYCLE_TIME + cycle_start);
/* printf("cycle_start 0x%02x now 0x%02x wait 0x%02x\n",
cycle_start, RTIMER_NOW(), CYCLE_TIME - (RTIMER_NOW() - cycle_start));*/
PT_YIELD(&pt);
}
}
PT_END(&pt);
}
/*---------------------------------------------------------------------------*/
#if CONTIKIMAC_CONF_ANNOUNCEMENTS
static int
parse_announcements(void)
{
/* Parse incoming announcements */
struct announcement_msg adata;
const rimeaddr_t *from;
int i;
memcpy(&adata, packetbuf_dataptr(),
MIN(packetbuf_datalen(), sizeof(adata)));
from = packetbuf_addr(PACKETBUF_ADDR_SENDER);
/* printf("%d.%d: probe from %d.%d with %d announcements\n",
rimeaddr_node_addr.u8[0], rimeaddr_node_addr.u8[1],
from->u8[0], from->u8[1], adata.num); */
/* for(i = 0; i < packetbuf_datalen(); ++i) {
printf("%02x ", ((uint8_t *)packetbuf_dataptr())[i]);
}
printf("\n"); */
if(adata.num / sizeof(struct announcement_data) > sizeof(struct announcement_msg)) {
/* Sanity check. The number of announcements is too large -
corrupt packet has been received. */
return 0;
}
for(i = 0; i < adata.num; ++i) {
/* printf("%d.%d: announcement %d: %d\n",
rimeaddr_node_addr.u8[0], rimeaddr_node_addr.u8[1],
adata.data[i].id,
adata.data[i].value); */
announcement_heard(from, adata.data[i].id, adata.data[i].value);
}
return i;
}
/*---------------------------------------------------------------------------*/
static int
format_announcement(char *hdr)
{
struct announcement_msg adata;
struct announcement *a;
/* Construct the announcements */
/* adata = (struct announcement_msg *)hdr; */
adata.announcement_magic[0] = ANNOUNCEMENT_MAGIC1;
adata.announcement_magic[1] = ANNOUNCEMENT_MAGIC2;
adata.num = 0;
for(a = announcement_list();
a != NULL && adata.num < ANNOUNCEMENT_MAX;
a = a->next) {
if(a->has_value) {
adata.data[adata.num].id = a->id;
adata.data[adata.num].value = a->value;
adata.num++;
}
}
memcpy(hdr, &adata, sizeof(struct announcement_msg));
if(adata.num > 0) {
return ANNOUNCEMENT_MSG_HEADERLEN +
sizeof(struct announcement_data) * adata.num;
} else {
return 0;
}
}
#endif /* CONTIKIMAC_CONF_ANNOUNCEMENTS */
/*---------------------------------------------------------------------------*/
static int
broadcast_rate_drop(void)
{
#if CONTIKIMAC_CONF_BROADCAST_RATE_LIMIT
if(!timer_expired(&broadcast_rate_timer)) {
broadcast_rate_counter++;
if(broadcast_rate_counter < CONTIKIMAC_CONF_BROADCAST_RATE_LIMIT) {
return 0;
} else {
return 1;
}
} else {
timer_set(&broadcast_rate_timer, CLOCK_SECOND);
broadcast_rate_counter = 0;
return 0;
}
#else /* CONTIKIMAC_CONF_BROADCAST_RATE_LIMIT */
return 0;
#endif /* CONTIKIMAC_CONF_BROADCAST_RATE_LIMIT */
}
/*---------------------------------------------------------------------------*/
static int
send_packet(mac_callback_t mac_callback, void *mac_callback_ptr)
{
rtimer_clock_t t0;
rtimer_clock_t encounter_time = 0, previous_txtime = 0;
int strobes;
uint8_t got_strobe_ack = 0;
int hdrlen, len;
uint8_t is_broadcast = 0;
uint8_t is_reliable = 0;
uint8_t is_known_receiver = 0;
uint8_t collisions;
int transmit_len;
int i;
int ret;
uint8_t contikimac_was_on;
#if WITH_CONTIKIMAC_HEADER
struct hdr *chdr;
#endif /* WITH_CONTIKIMAC_HEADER */
if(packetbuf_totlen() == 0) {
PRINTF("contikimac: send_packet data len 0\n");
return MAC_TX_ERR_FATAL;
}
packetbuf_set_addr(PACKETBUF_ADDR_SENDER, &rimeaddr_node_addr);
if(rimeaddr_cmp(packetbuf_addr(PACKETBUF_ADDR_RECEIVER), &rimeaddr_null)) {
is_broadcast = 1;
PRINTDEBUG("contikimac: send broadcast\n");
if(broadcast_rate_drop()) {
return MAC_TX_COLLISION;
}
} else {
#if UIP_CONF_IPV6
PRINTDEBUG("contikimac: send unicast to %02x%02x:%02x%02x:%02x%02x:%02x%02x\n",
packetbuf_addr(PACKETBUF_ADDR_RECEIVER)->u8[0],
packetbuf_addr(PACKETBUF_ADDR_RECEIVER)->u8[1],
packetbuf_addr(PACKETBUF_ADDR_RECEIVER)->u8[2],
packetbuf_addr(PACKETBUF_ADDR_RECEIVER)->u8[3],
packetbuf_addr(PACKETBUF_ADDR_RECEIVER)->u8[4],
packetbuf_addr(PACKETBUF_ADDR_RECEIVER)->u8[5],
packetbuf_addr(PACKETBUF_ADDR_RECEIVER)->u8[6],
packetbuf_addr(PACKETBUF_ADDR_RECEIVER)->u8[7]);
#else /* UIP_CONF_IPV6 */
PRINTDEBUG("contikimac: send unicast to %u.%u\n",
packetbuf_addr(PACKETBUF_ADDR_RECEIVER)->u8[0],
packetbuf_addr(PACKETBUF_ADDR_RECEIVER)->u8[1]);
#endif /* UIP_CONF_IPV6 */
}
is_reliable = packetbuf_attr(PACKETBUF_ATTR_RELIABLE) ||
packetbuf_attr(PACKETBUF_ATTR_ERELIABLE);
if(WITH_STREAMING) {
if(packetbuf_attr(PACKETBUF_ATTR_PACKET_TYPE) ==
PACKETBUF_ATTR_PACKET_TYPE_STREAM) {
if(rimeaddr_cmp(&is_streaming_to, &rimeaddr_null)) {
rimeaddr_copy(&is_streaming_to,
packetbuf_addr(PACKETBUF_ADDR_RECEIVER));
} else if(!rimeaddr_cmp
(&is_streaming_to, packetbuf_addr(PACKETBUF_ADDR_RECEIVER))) {
rimeaddr_copy(&is_streaming_to_too,
packetbuf_addr(PACKETBUF_ADDR_RECEIVER));
}
stream_until = RTIMER_NOW() + DEFAULT_STREAM_TIME;
is_streaming = 1;
} else {
is_streaming = 0;
}
}
if(is_streaming) {
packetbuf_set_attr(PACKETBUF_ATTR_PENDING, 1);
}
packetbuf_set_attr(PACKETBUF_ATTR_MAC_ACK, 1);
if(WITH_CONTIKIMAC_HEADER) {
hdrlen = packetbuf_totlen();
if(packetbuf_hdralloc(sizeof(struct hdr)) == 0) {
/* Failed to allocate space for contikimac header */
PRINTF("contikimac: send failed, too large header\n");
return MAC_TX_ERR_FATAL;
}
chdr = packetbuf_hdrptr();
chdr->id = CONTIKIMAC_ID;
chdr->len = hdrlen;
/* Create the MAC header for the data packet. */
hdrlen = NETSTACK_FRAMER.create();
if(hdrlen == 0) {
/* Failed to send */
PRINTF("contikimac: send failed, too large header\n");
packetbuf_hdr_remove(sizeof(struct hdr));
return MAC_TX_ERR_FATAL;
}
hdrlen += sizeof(struct hdr);
} else {
/* Create the MAC header for the data packet. */
hdrlen = NETSTACK_FRAMER.create();
if(hdrlen == 0) {
/* Failed to send */
PRINTF("contikimac: send failed, too large header\n");
return MAC_TX_ERR_FATAL;
}
}
/* Make sure that the packet is longer or equal to the shortest
packet length. */
transmit_len = packetbuf_totlen();
if(transmit_len < SHORTEST_PACKET_SIZE) {
#if 0
/* Pad with zeroes */
uint8_t *ptr;
ptr = packetbuf_dataptr();
memset(ptr + packetbuf_datalen(), 0, SHORTEST_PACKET_SIZE - packetbuf_totlen());
#endif
PRINTF("contikimac: shorter than shortest (%d)\n", packetbuf_totlen());
transmit_len = SHORTEST_PACKET_SIZE;
}
packetbuf_compact();
NETSTACK_RADIO.prepare(packetbuf_hdrptr(), transmit_len);
/* Remove the MAC-layer header since it will be recreated next time around. */
packetbuf_hdr_remove(hdrlen);
if(!is_broadcast && !is_streaming) {
#if WITH_PHASE_OPTIMIZATION
ret = phase_wait(&phase_list, packetbuf_addr(PACKETBUF_ADDR_RECEIVER),
CYCLE_TIME, GUARD_TIME,
mac_callback, mac_callback_ptr);
if(ret == PHASE_DEFERRED) {
return MAC_TX_DEFERRED;
}
if(ret != PHASE_UNKNOWN) {
is_known_receiver = 1;
}
#endif /* WITH_PHASE_OPTIMIZATION */
}
/* By setting we_are_sending to one, we ensure that the rtimer
powercycle interrupt do not interfere with us sending the packet. */
we_are_sending = 1;
/* If we have a pending packet in the radio, we should not send now,
because we will trash the received packet. Instead, we signal
that we have a collision, which lets the packet be received. This
packet will be retransmitted later by the MAC protocol
instread. */
if(NETSTACK_RADIO.receiving_packet() || NETSTACK_RADIO.pending_packet()) {
we_are_sending = 0;
PRINTF("contikimac: collision receiving %d, pending %d\n",
NETSTACK_RADIO.receiving_packet(), NETSTACK_RADIO.pending_packet());
return MAC_TX_COLLISION;
}
/* Switch off the radio to ensure that we didn't start sending while
the radio was doing a channel check. */
off();
strobes = 0;
/* Send a train of strobes until the receiver answers with an ACK. */
collisions = 0;
got_strobe_ack = 0;
/* Set contikimac_is_on to one to allow the on() and off() functions
to control the radio. We restore the old value of
contikimac_is_on when we are done. */
contikimac_was_on = contikimac_is_on;
contikimac_is_on = 1;
if(is_streaming == 0) {
/* Check if there are any transmissions by others. */
for(i = 0; i < CCA_COUNT_MAX; ++i) {
t0 = RTIMER_NOW();
on();
#if NURTIMER
while(RTIMER_CLOCK_LT(t0, RTIMER_NOW(), t0 + CCA_CHECK_TIME));
#else
while(RTIMER_CLOCK_LT(RTIMER_NOW(), t0 + CCA_CHECK_TIME)) { }
#endif
if(NETSTACK_RADIO.channel_clear() == 0) {
collisions++;
off();
break;
}
off();
t0 = RTIMER_NOW();
#if NURTIMER
while(RTIMER_CLOCK_LT(t0, RTIMER_NOW(), t0 + CCA_SLEEP_TIME));
#else
while(RTIMER_CLOCK_LT(RTIMER_NOW(), t0 + CCA_SLEEP_TIME)) { }
#endif
}
}
if(collisions > 0) {
we_are_sending = 0;
off();
PRINTF("contikimac: collisions before sending\n");
contikimac_is_on = contikimac_was_on;
return MAC_TX_COLLISION;
}
if(!is_broadcast) {
on();
}
watchdog_periodic();
t0 = RTIMER_NOW();
#if NURTIMER
for(strobes = 0, collisions = 0;
got_strobe_ack == 0 && collisions == 0 &&
RTIMER_CLOCK_LT(t0, RTIMER_NOW(), t0 + STROBE_TIME); strobes++) {
#else
for(strobes = 0, collisions = 0;
got_strobe_ack == 0 && collisions == 0 &&
RTIMER_CLOCK_LT(RTIMER_NOW(), t0 + STROBE_TIME); strobes++) {
#endif
watchdog_periodic();
if(is_known_receiver && !RTIMER_CLOCK_LT(RTIMER_NOW(), t0 + MAX_PHASE_STROBE_TIME)) {
PRINTF("miss to %d\n", packetbuf_addr(PACKETBUF_ADDR_RECEIVER)->u8[0]);
break;
}
len = 0;
previous_txtime = RTIMER_NOW();
{
rtimer_clock_t wt;
rtimer_clock_t txtime;
int ret;
txtime = RTIMER_NOW();
ret = NETSTACK_RADIO.transmit(transmit_len);
wt = RTIMER_NOW();
#if NURTIMER
while(RTIMER_CLOCK_LT(wt, RTIMER_NOW(), wt + INTER_PACKET_INTERVAL));
#else
while(RTIMER_CLOCK_LT(RTIMER_NOW(), wt + INTER_PACKET_INTERVAL)) { }
#endif
if(!is_broadcast && (NETSTACK_RADIO.receiving_packet() ||
NETSTACK_RADIO.pending_packet() ||
NETSTACK_RADIO.channel_clear() == 0)) {
uint8_t ackbuf[ACK_LEN];
wt = RTIMER_NOW();
#if NURTIMER
while(RTIMER_CLOCK_LT(wt, RTIMER_NOW(), wt + AFTER_ACK_DETECTECT_WAIT_TIME));
#else
while(RTIMER_CLOCK_LT(RTIMER_NOW(), wt + AFTER_ACK_DETECTECT_WAIT_TIME)) { }
#endif
len = NETSTACK_RADIO.read(ackbuf, ACK_LEN);
if(len == ACK_LEN) {
got_strobe_ack = 1;
encounter_time = previous_txtime;
break;
} else {
PRINTF("contikimac: collisions while sending\n");
collisions++;
}
}
previous_txtime = txtime;
}
}
off();
PRINTF("contikimac: send (strobes=%u, len=%u, %s, %s), done\n", strobes,
packetbuf_totlen(),
got_strobe_ack ? "ack" : "no ack",
collisions ? "collision" : "no collision");
#if CONTIKIMAC_CONF_COMPOWER
/* Accumulate the power consumption for the packet transmission. */
compower_accumulate(&current_packet);
/* Convert the accumulated power consumption for the transmitted
packet to packet attributes so that the higher levels can keep
track of the amount of energy spent on transmitting the
packet. */
compower_attrconv(&current_packet);
/* Clear the accumulated power consumption so that it is ready for
the next packet. */
compower_clear(&current_packet);
#endif /* CONTIKIMAC_CONF_COMPOWER */
contikimac_is_on = contikimac_was_on;
we_are_sending = 0;
/* Determine the return value that we will return from the
function. We must pass this value to the phase module before we
return from the function. */
if(collisions > 0) {
ret = MAC_TX_COLLISION;
} else if(!is_broadcast && !got_strobe_ack) {
ret = MAC_TX_NOACK;
} else {
ret = MAC_TX_OK;
}
#if WITH_PHASE_OPTIMIZATION
if(is_known_receiver && got_strobe_ack) {
PRINTF("no miss %d wake-ups %d\n", packetbuf_addr(PACKETBUF_ADDR_RECEIVER)->u8[0],
strobes);
}
if(!is_broadcast) {
if(collisions == 0 && is_streaming == 0) {
phase_update(&phase_list, packetbuf_addr(PACKETBUF_ADDR_RECEIVER), encounter_time,
ret);
}
}
#endif /* WITH_PHASE_OPTIMIZATION */
return ret;
}
/*---------------------------------------------------------------------------*/
static void
qsend_packet(mac_callback_t sent, void *ptr)
{
int ret = send_packet(sent, ptr);
if(ret != MAC_TX_DEFERRED) {
// printf("contikimac qsend_packet %p\n", ptr);
mac_call_sent_callback(sent, ptr, ret, 1);
}
}
/*---------------------------------------------------------------------------*/
static void
input_packet(void)
{
/* We have received the packet, so we can go back to being
asleep. */
off();
/* printf("cycle_start 0x%02x 0x%02x\n", cycle_start, cycle_start % CYCLE_TIME);*/
if(packetbuf_totlen() > 0 && NETSTACK_FRAMER.parse()) {
#if WITH_CONTIKIMAC_HEADER
struct hdr *chdr;
chdr = packetbuf_dataptr();
if(chdr->id != CONTIKIMAC_ID) {
PRINTF("contikimac: failed to parse hdr (%u)\n", packetbuf_totlen());
return;
}
packetbuf_hdrreduce(sizeof(struct hdr));
packetbuf_set_datalen(chdr->len);
#endif /* WITH_CONTIKIMAC_HEADER */
if(packetbuf_datalen() > 0 &&
packetbuf_totlen() > 0 &&
(rimeaddr_cmp(packetbuf_addr(PACKETBUF_ADDR_RECEIVER),
&rimeaddr_node_addr) ||
rimeaddr_cmp(packetbuf_addr(PACKETBUF_ADDR_RECEIVER),
&rimeaddr_null))) {
/* This is a regular packet that is destined to us or to the
broadcast address. */
#if CONTIKIMAC_CONF_ANNOUNCEMENTS
{
struct announcement_msg *hdr = packetbuf_dataptr();
uint8_t magic[2];
memcpy(magic, hdr->announcement_magic, 2);
if(magic[0] == ANNOUNCEMENT_MAGIC1 &&
magic[1] == ANNOUNCEMENT_MAGIC2) {
parse_announcements();
}
}
#endif /* CONTIKIMAC_CONF_ANNOUNCEMENTS */
#if WITH_PHASE_OPTIMIZATION
/* If the sender has set its pending flag, it has its radio
turned on and we should drop the phase estimation that we
have from before. */
if(packetbuf_attr(PACKETBUF_ATTR_PENDING)) {
phase_remove(&phase_list, packetbuf_addr(PACKETBUF_ADDR_SENDER));
}
#endif /* WITH_PHASE_OPTIMIZATION */
/* Check for duplicate packet by comparing the sequence number
of the incoming packet with the last few ones we saw. */
{
int i;
for(i = 0; i < MAX_SEQNOS; ++i) {
if(packetbuf_attr(PACKETBUF_ATTR_PACKET_ID) == received_seqnos[i].seqno &&
rimeaddr_cmp(packetbuf_addr(PACKETBUF_ADDR_SENDER),
&received_seqnos[i].sender)) {
/* Drop the packet. */
/* printf("Drop duplicate ContikiMAC layer packet\n");*/
return;
}
}
for(i = MAX_SEQNOS - 1; i > 0; --i) {
memcpy(&received_seqnos[i], &received_seqnos[i - 1],
sizeof(struct seqno));
}
received_seqnos[0].seqno = packetbuf_attr(PACKETBUF_ATTR_PACKET_ID);
rimeaddr_copy(&received_seqnos[0].sender,
packetbuf_addr(PACKETBUF_ADDR_SENDER));
}
#if CONTIKIMAC_CONF_COMPOWER
/* Accumulate the power consumption for the packet reception. */
compower_accumulate(&current_packet);
/* Convert the accumulated power consumption for the received
packet to packet attributes so that the higher levels can
keep track of the amount of energy spent on receiving the
packet. */
compower_attrconv(&current_packet);
/* Clear the accumulated power consumption so that it is ready
for the next packet. */
compower_clear(&current_packet);
#endif /* CONTIKIMAC_CONF_COMPOWER */
PRINTDEBUG("contikimac: data (%u)\n", packetbuf_datalen());
NETSTACK_MAC.input();
return;
} else {
PRINTDEBUG("contikimac: data not for us\n");
}
} else {
PRINTF("contikimac: failed to parse (%u)\n", packetbuf_totlen());
}
}
/*---------------------------------------------------------------------------*/
#if CONTIKIMAC_CONF_ANNOUNCEMENTS
static void
send_announcement(void *ptr)
{
int announcement_len;
int transmit_len;
#if WITH_CONTIKIMAC_HEADER
struct hdr *chdr;
#endif /* WITH_CONTIKIMAC_HEADER */
/* Set up the probe header. */
packetbuf_clear();
announcement_len = format_announcement(packetbuf_dataptr());
if(announcement_len > 0) {
packetbuf_set_datalen(announcement_len);
packetbuf_set_addr(PACKETBUF_ADDR_SENDER, &rimeaddr_node_addr);
packetbuf_set_addr(PACKETBUF_ADDR_RECEIVER, &rimeaddr_null);
packetbuf_set_attr(PACKETBUF_ATTR_RADIO_TXPOWER,
announcement_radio_txpower);
#if WITH_CONTIKIMAC_HEADER
transmit_len = packetbuf_totlen();
if(packetbuf_hdralloc(sizeof(struct hdr)) == 0) {
/* Failed to allocate space for contikimac header */
PRINTF("contikimac: send announcement failed, too large header\n");
return;
}
chdr = packetbuf_hdrptr();
chdr->id = CONTIKIMAC_ID;
chdr->len = transmit_len;
#endif /* WITH_CONTIKIMAC_HEADER */
if(NETSTACK_FRAMER.create()) {
rtimer_clock_t t;
int i, collisions;
we_are_sending = 1;
/* Make sure that the packet is longer or equal to the shorest
packet length. */
transmit_len = packetbuf_totlen();
if(transmit_len < SHORTEST_PACKET_SIZE) {
#if 0
/* Pad with zeroes */
uint8_t *ptr;
ptr = packetbuf_dataptr();
memset(ptr + packetbuf_datalen(), 0, SHORTEST_PACKET_SIZE - transmit_len);
#endif
PRINTF("contikimac: shorter than shortest (%d)\n", packetbuf_totlen());
transmit_len = SHORTEST_PACKET_SIZE;
}
collisions = 0;
/* Check for collisions */
for(i = 0; i < CCA_COUNT_MAX; ++i) {
t = RTIMER_NOW();
on();
#if NURTIMER
while(RTIMER_CLOCK_LT(t, RTIMER_NOW(), t + CCA_CHECK_TIME));
#else
while(RTIMER_CLOCK_LT(RTIMER_NOW(), t + CCA_CHECK_TIME));
#endif
if(NETSTACK_RADIO.channel_clear() == 0) {
collisions++;
off();
break;
}
off();
#if NURTIMER
while(RTIMER_CLOCK_LT(t0, RTIMER_NOW(), t + CCA_SLEEP_TIME + CCA_CHECK_TIME));
#else
while(RTIMER_CLOCK_LT(RTIMER_NOW(), t + CCA_SLEEP_TIME + CCA_CHECK_TIME)) { }
#endif
}
if(collisions == 0) {
NETSTACK_RADIO.prepare(packetbuf_hdrptr(), transmit_len);
NETSTACK_RADIO.transmit(transmit_len);
t = RTIMER_NOW();
#if NURTIMER
while(RTIMER_CLOCK_LT(t, RTIMER_NOW(), t + INTER_PACKET_INTERVAL));
#else
while(RTIMER_CLOCK_LT(RTIMER_NOW(), t + INTER_PACKET_INTERVAL)) { }
#endif
NETSTACK_RADIO.transmit(transmit_len);
}
we_are_sending = 0;
}
}
}
/*---------------------------------------------------------------------------*/
static void
cycle_announcement(void *ptr)
{
ctimer_set(&announcement_ctimer, ANNOUNCEMENT_TIME,
send_announcement, NULL);
ctimer_set(&announcement_cycle_ctimer, ANNOUNCEMENT_PERIOD,
cycle_announcement, NULL);
if(is_snooping > 0) {
is_snooping--;
/* printf("is_snooping %d\n", is_snooping); */
}
}
/*---------------------------------------------------------------------------*/
static void
listen_callback(int periods)
{
printf("Snoop\n");
is_snooping = periods + 1;
}
#endif /* CONTIKIMAC_CONF_ANNOUNCEMENTS */
/*---------------------------------------------------------------------------*/
void
contikimac_set_announcement_radio_txpower(int txpower)
{
#if CONTIKIMAC_CONF_ANNOUNCEMENTS
announcement_radio_txpower = txpower;
#endif /* CONTIKIMAC_CONF_ANNOUNCEMENTS */
}
/*---------------------------------------------------------------------------*/
static void
init(void)
{
radio_is_on = 0;
PT_INIT(&pt);
#if NURTIMER
rtimer_setup(&rt, RTIMER_HARD,
(void (*)(struct rtimer *, void *, int status))powercycle,
NULL);
rtimer_schedule(&rt, CYCLE_TIME, 1);
#else
rtimer_set(&rt, RTIMER_NOW() + CYCLE_TIME, 1,
(void (*)(struct rtimer *, void *))powercycle, NULL);
#endif
contikimac_is_on = 1;
#if WITH_PHASE_OPTIMIZATION
phase_init(&phase_list);
#endif /* WITH_PHASE_OPTIMIZATION */
#if CONTIKIMAC_CONF_ANNOUNCEMENTS
announcement_register_listen_callback(listen_callback);
ctimer_set(&announcement_cycle_ctimer, ANNOUNCEMENT_TIME,
cycle_announcement, NULL);
#endif /* CONTIKIMAC_CONF_ANNOUNCEMENTS */
}
/*---------------------------------------------------------------------------*/
static int
turn_on(void)
{
if(contikimac_is_on == 0) {
contikimac_is_on = 1;
contikimac_keep_radio_on = 0;
#if NURTIMER
rtimer_schedule(&rt, CYCLE_TIME, 1);
#else
rtimer_set(&rt, RTIMER_NOW() + CYCLE_TIME, 1,
(void (*)(struct rtimer *, void *))powercycle, NULL);
#endif
}
return 1;
}
/*---------------------------------------------------------------------------*/
static int
turn_off(int keep_radio_on)
{
contikimac_is_on = 0;
contikimac_keep_radio_on = keep_radio_on;
if(keep_radio_on) {
radio_is_on = 1;
return NETSTACK_RADIO.on();
} else {
radio_is_on = 0;
return NETSTACK_RADIO.off();
}
}
/*---------------------------------------------------------------------------*/
static unsigned short
duty_cycle(void)
{
return (1ul * CLOCK_SECOND * CYCLE_TIME) / RTIMER_ARCH_SECOND;
}
/*---------------------------------------------------------------------------*/
const struct rdc_driver contikimac_driver = {
"ContikiMAC",
init,
qsend_packet,
input_packet,
turn_on,
turn_off,
duty_cycle,
};
/*---------------------------------------------------------------------------*/
uint16_t
contikimac_debug_print(void)
{
static rtimer_clock_t one_cycle_start;
printf("Drift %d\n", (one_cycle_start - cycle_start) % CYCLE_TIME);
one_cycle_start = cycle_start;
return 0;
}
/*---------------------------------------------------------------------------*/