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apache / mynewt-nimble / refs/heads/master / . / nimble / controller / src / ble_ll_sched.c
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/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
#include <stdint.h>
#include <stdlib.h>
#include <assert.h>
#include <string.h>
#include "ble/xcvr.h"
#include "controller/ble_phy.h"
#include "controller/ble_ll.h"
#include "controller/ble_ll_pdu.h"
#include "controller/ble_ll_sched.h"
#include "controller/ble_ll_adv.h"
#include "controller/ble_ll_scan.h"
#include "controller/ble_ll_scan_aux.h"
#include "controller/ble_ll_rfmgmt.h"
#include "controller/ble_ll_trace.h"
#include "controller/ble_ll_tmr.h"
#include "controller/ble_ll_sync.h"
#include "controller/ble_ll_iso_big.h"
#if MYNEWT_VAL(BLE_LL_EXT)
#include "controller/ble_ll_ext.h"
#endif
#include "ble_ll_priv.h"
#include "ble_ll_conn_priv.h"
#define BLE_LL_SCHED_MAX_DELAY_ANY (0x7fffffff)
static struct ble_ll_tmr g_ble_ll_sched_timer;
uint8_t g_ble_ll_sched_offset_ticks;
#if (BLE_LL_SCHED_DEBUG == 1)
int32_t g_ble_ll_sched_max_late;
int32_t g_ble_ll_sched_max_early;
#endif
#if MYNEWT_VAL(BLE_LL_CONN_STRICT_SCHED)
struct ble_ll_sched_css {
uint8_t enabled;
#if !MYNEWT_VAL(BLE_LL_CONN_STRICT_SCHED_FIXED)
uint32_t slot_us;
uint32_t period_slots;
#endif
uint32_t period_anchor_ticks;
uint8_t period_anchor_rem_us;
uint8_t period_anchor_idx;
uint16_t period_anchor_slot_idx;
};
static struct ble_ll_sched_css g_ble_ll_sched_css = {
#if !MYNEWT_VAL(BLE_LL_CONN_STRICT_SCHED_FIXED)
.slot_us = MYNEWT_VAL(BLE_LL_CONN_STRICT_SCHED_SLOT_US),
.period_slots = MYNEWT_VAL(BLE_LL_CONN_STRICT_SCHED_PERIOD_SLOTS),
#endif
};
#endif
/* XXX: TODO:
* 1) Add some accounting to the schedule code to see how late we are
* (min/max?)
*
* 2) Need to determine how we really want to handle the case when we execute
* a schedule item but there is a current event. We could:
* -> Reschedule the schedule item and let current event finish
* -> Kill the current event and run the scheduled item.
* -> Disable schedule timer while in an event; could cause us to be late.
* -> Wait for current event to finish hoping it does before schedule item.
*/
/* Queue for timers */
static TAILQ_HEAD(ll_sched_qhead, ble_ll_sched_item) g_ble_ll_sched_q;
static uint8_t g_ble_ll_sched_q_head_changed;
static int
preempt_any(struct ble_ll_sched_item *sch,
struct ble_ll_sched_item *item)
{
return 1;
}
static int
preempt_none(struct ble_ll_sched_item *sch,
struct ble_ll_sched_item *item)
{
return 0;
}
static int
preempt_any_except_conn(struct ble_ll_sched_item *sch,
struct ble_ll_sched_item *item)
{
BLE_LL_ASSERT(sch->sched_type == BLE_LL_SCHED_TYPE_CONN);
if (item->sched_type != BLE_LL_SCHED_TYPE_CONN) {
return 1;
}
return ble_ll_conn_is_lru(sch->cb_arg, item->cb_arg);
}
static inline int
ble_ll_sched_check_overlap(struct ble_ll_sched_item *sch1,
struct ble_ll_sched_item *sch2)
{
/* Note: item ranges are defined as [start, end) so items do not overlap
* if one item starts at the same time as another ends.
*/
return LL_TMR_GT(sch1->end_time, sch2->start_time) &&
LL_TMR_GT(sch2->end_time, sch1->start_time);
}
static void
ble_ll_sched_preempt(struct ble_ll_sched_item *sch,
struct ble_ll_sched_item *first)
{
struct ble_ll_sched_item *entry;
struct ble_ll_sched_item *next;
#if MYNEWT_VAL(BLE_LL_ROLE_PERIPHERAL) || MYNEWT_VAL(BLE_LL_ROLE_CENTRAL)
struct ble_ll_conn_sm *connsm;
#endif
entry = first;
do {
next = TAILQ_NEXT(entry, link);
TAILQ_REMOVE(&g_ble_ll_sched_q, entry, link);
entry->enqueued = 0;
switch (entry->sched_type) {
#if MYNEWT_VAL(BLE_LL_ROLE_CENTRAL) || MYNEWT_VAL(BLE_LL_ROLE_PERIPHERAL)
case BLE_LL_SCHED_TYPE_CONN:
connsm = (struct ble_ll_conn_sm *)entry->cb_arg;
ble_ll_event_add(&connsm->conn_ev_end);
break;
#endif
#if MYNEWT_VAL(BLE_LL_ROLE_BROADCASTER)
case BLE_LL_SCHED_TYPE_ADV:
ble_ll_adv_preempted(entry->cb_arg);
break;
#endif
#if MYNEWT_VAL(BLE_LL_CFG_FEAT_LL_EXT_ADV) && MYNEWT_VAL(BLE_LL_ROLE_OBSERVER)
case BLE_LL_SCHED_TYPE_SCAN_AUX:
ble_ll_scan_aux_break(entry->cb_arg);
break;
#endif
#if MYNEWT_VAL(BLE_LL_CFG_FEAT_LL_PERIODIC_ADV)
#if MYNEWT_VAL(BLE_LL_ROLE_BROADCASTER)
case BLE_LL_SCHED_TYPE_PERIODIC:
ble_ll_adv_periodic_rmvd_from_sched(entry->cb_arg);
break;
#endif
#if MYNEWT_VAL(BLE_LL_CFG_FEAT_LL_EXT_ADV) && MYNEWT_VAL(BLE_LL_ROLE_OBSERVER)
case BLE_LL_SCHED_TYPE_SYNC:
ble_ll_sync_rmvd_from_sched(entry->cb_arg);
break;
#endif
#endif
#if MYNEWT_VAL(BLE_LL_ISO_BROADCASTER)
case BLE_LL_SCHED_TYPE_BIG:
/* FIXME sometimes it may be useful to preempt... */
BLE_LL_ASSERT(0);
break;
#endif
#if MYNEWT_VAL(BLE_LL_EXT)
case BLE_LL_SCHED_TYPE_EXTERNAL:
ble_ll_ext_sched_removed(entry);
break;
#endif
default:
BLE_LL_ASSERT(0);
break;
}
entry = next;
} while (entry != sch);
}
static inline void
ble_ll_sched_q_head_changed(void)
{
if (g_ble_ll_sched_q_head_changed) {
return;
}
g_ble_ll_sched_q_head_changed = 1;
ble_ll_tmr_stop(&g_ble_ll_sched_timer);
}
void
ble_ll_sched_restart(void)
{
struct ble_ll_sched_item *first;
if (!g_ble_ll_sched_q_head_changed) {
return;
}
g_ble_ll_sched_q_head_changed = 0;
first = TAILQ_FIRST(&g_ble_ll_sched_q);
ble_ll_rfmgmt_sched_changed(first);
if (first) {
ble_ll_tmr_start(&g_ble_ll_sched_timer, first->start_time);
}
}
int
ble_ll_sched_insert(struct ble_ll_sched_item *sch, uint32_t max_delay,
ble_ll_sched_preempt_cb_t preempt_cb)
{
struct ble_ll_sched_item *preempt_first;
struct ble_ll_sched_item *first;
struct ble_ll_sched_item *entry;
uint32_t max_start_time;
uint32_t duration;
OS_ASSERT_CRITICAL();
preempt_first = NULL;
max_start_time = sch->start_time + max_delay;
duration = sch->end_time - sch->start_time;
first = TAILQ_FIRST(&g_ble_ll_sched_q);
if (!first) {
TAILQ_INSERT_HEAD(&g_ble_ll_sched_q, sch, link);
sch->enqueued = 1;
goto done;
}
TAILQ_FOREACH(entry, &g_ble_ll_sched_q, link) {
if (LL_TMR_LEQ(sch->end_time, entry->start_time)) {
TAILQ_INSERT_BEFORE(entry, sch, link);
sch->enqueued = 1;
goto done;
}
/* If current item overlaps our item check if we can preempt. If we
* cannot preempt, move our item past current item and see if it's
* still within allowed range.
*/
if (ble_ll_sched_check_overlap(sch, entry)) {
if (preempt_cb(sch, entry)) {
if (!preempt_first) {
preempt_first = entry;
}
} else {
preempt_first = NULL;
/*
* For the 32768 Hz crystal in nrf chip, 1 tick is 30.517us.
* The connection state machine use anchor point to store the
* cpu ticks and anchor_point_usec to store the remainder.
* Therefore, to compensate the inaccuracy of the crystal, the
* ticks of anchor_point will be add with 1 once the value of
* anchor_point_usec exceed 31. If two connections have same
* connection interval, the time difference between the two
* start of schedule item will decreased 1, which lead to
* an overlap. To prevent this from happenning, we set the
* start_time of sch to 1 cpu tick after the end_time of entry.
*/
sch->start_time = entry->end_time + 1;
if ((max_delay == 0) || LL_TMR_GEQ(sch->start_time,
max_start_time)) {
sch->enqueued = 0;
goto done;
}
sch->end_time = sch->start_time + duration;
}
}
}
if (!entry) {
TAILQ_INSERT_TAIL(&g_ble_ll_sched_q, sch, link);
sch->enqueued = 1;
}
done:
if (preempt_first) {
BLE_LL_ASSERT(sch->enqueued);
ble_ll_sched_preempt(sch, preempt_first);
}
/* Pause scheduler if inserted as 1st item, we do not want to miss this
* one. Caller should restart outside critical section.
*/
if (TAILQ_FIRST(&g_ble_ll_sched_q) == sch) {
BLE_LL_ASSERT(sch->enqueued);
ble_ll_sched_q_head_changed();
}
return sch->enqueued ? 0 : -1;
}
/*
* Determines if the schedule item overlaps the currently running schedule
* item. We only care about connection schedule items
*/
static int
ble_ll_sched_overlaps_current(struct ble_ll_sched_item *sch)
{
int rc = 0;
#if MYNEWT_VAL(BLE_LL_ROLE_PERIPHERAL) || MYNEWT_VAL(BLE_LL_ROLE_CENTRAL)
uint32_t ce_end_time;
if (ble_ll_state_get() == BLE_LL_STATE_CONNECTION) {
ce_end_time = ble_ll_conn_get_ce_end_time();
if (LL_TMR_GT(ce_end_time, sch->start_time)) {
rc = 1;
}
}
#endif
return rc;
}
int
ble_ll_sched_conn_reschedule(struct ble_ll_conn_sm *connsm)
{
#if MYNEWT_VAL(BLE_LL_CONN_STRICT_SCHED)
struct ble_ll_sched_css *css = &g_ble_ll_sched_css;
#endif
struct ble_ll_sched_item *sch;
#if MYNEWT_VAL(BLE_LL_ROLE_PERIPHERAL)
uint32_t usecs;
#endif
os_sr_t sr;
int rc;
/* Get schedule element from connection */
sch = &connsm->conn_sch;
/* Set schedule start and end times */
sch->start_time = connsm->anchor_point - g_ble_ll_sched_offset_ticks;
switch (connsm->conn_role) {
#if MYNEWT_VAL(BLE_LL_ROLE_CENTRAL)
case BLE_LL_CONN_ROLE_CENTRAL:
sch->remainder = connsm->anchor_point_usecs;
break;
#endif
#if MYNEWT_VAL(BLE_LL_ROLE_PERIPHERAL)
case BLE_LL_CONN_ROLE_PERIPHERAL:
usecs = connsm->periph_cur_window_widening;
sch->start_time -= (ble_ll_tmr_u2t(usecs) + 1);
sch->remainder = 0;
break;
#endif
default:
BLE_LL_ASSERT(0);
break;
}
sch->end_time = connsm->ce_end_time;
/* Better be past current time or we just leave */
if (LL_TMR_LT(sch->start_time, ble_ll_tmr_get())) {
return -1;
}
OS_ENTER_CRITICAL(sr);
if (ble_ll_sched_overlaps_current(sch)) {
OS_EXIT_CRITICAL(sr);
return -1;
}
rc = ble_ll_sched_insert(sch, 0, preempt_any_except_conn);
#if MYNEWT_VAL(BLE_LL_CONN_STRICT_SCHED)
/* Store new anchor point for strict scheduling if successfully scheduled
* reference connection.
*/
if ((rc == 0) && (connsm == g_ble_ll_conn_css_ref)) {
css->period_anchor_idx = connsm->css_period_idx;
css->period_anchor_slot_idx = connsm->css_slot_idx;
css->period_anchor_ticks = connsm->anchor_point;
css->period_anchor_rem_us = connsm->anchor_point_usecs;
}
#endif
OS_EXIT_CRITICAL(sr);
ble_ll_sched_restart();
return rc;
}
/**
* Called to schedule a connection when the current role is central.
*
* Context: Interrupt
*
* @param connsm
* @param ble_hdr
* @param pyld_len
*
* @return int
*/
int
ble_ll_sched_conn_central_new(struct ble_ll_conn_sm *connsm,
struct ble_mbuf_hdr *ble_hdr, uint8_t pyld_len)
{
#if MYNEWT_VAL(BLE_LL_CONN_STRICT_SCHED)
struct ble_ll_sched_css *css = &g_ble_ll_sched_css;
uint8_t rem_us;
#endif
struct ble_ll_sched_item *sch;
uint32_t orig_start_time;
uint32_t earliest_start = 0;
uint32_t min_win_offset;
uint32_t max_delay;
uint32_t adv_rxend;
bool calc_sch = true;
os_sr_t sr;
int rc;
/* Get schedule element from connection */
sch = &connsm->conn_sch;
/* XXX:
* The calculations for the 32kHz crystal bear alot of explanation. The
* earliest possible time that the central can start the connection with a
* peripheral is 1.25 msecs from the end of the connection request. The
* connection request is sent an IFS time from the end of the advertising
* packet that was received plus the time it takes to send the connection
* request. At 1 Mbps, this is 1752 usecs, or 57.41 ticks. Using 57 ticks
* makes us off ~13 usecs. Since we dont want to actually calculate the
* receive end time tick (this would take too long), we assume the end of
* the advertising PDU is 'now' (we call os_cputime_get32). We dont know
* how much time it will take to service the ISR but if we are more than the
* rx to tx time of the chip we will not be successful transmitting the
* connect request. All this means is that we presume that the peripheral will
* receive the connect request later than we expect but no earlier than
* 13 usecs before (this is important).
*
* The code then attempts to schedule the connection at the
* earliest time although this may not be possible. When the actual
* schedule start time is determined, the central has to determine if this
* time is more than a transmit window offset interval (1.25 msecs). The
* central has to tell the peripheral how many transmit window offsets there are
* from the earliest possible time to when the actual transmit start will
* occur. Later in this function you will see the calculation. The actual
* transmission start has to occur within the transmit window. The transmit
* window interval is in units of 1.25 msecs and has to be at least 1. To
* make things a bit easier (but less power efficient for the peripheral), we
* use a transmit window of 2. We do this because we dont quite know the
* exact start of the transmission and if we are too early or too late we
* could miss the transmit window. A final note: the actual transmission
* start (the anchor point) is sched offset ticks from the schedule start
* time. We dont add this to the calculation when calculating the window
* offset. The reason we dont do this is we want to insure we transmit
* after the window offset we tell the peripheral. For example, say we think
* we are transmitting 1253 usecs from the earliest start. This would cause
* us to send a transmit window offset of 1. Since we are actually
* transmitting earlier than the peripheral thinks we could end up transmitting
* before the window offset. Transmitting later is fine since we have the
* transmit window to do so. Transmitting before is bad, since the peripheral
* wont be listening. We could do better calculation if we wanted to use
* a transmit window of 1 as opposed to 2, but for now we dont care.
*/
adv_rxend = ble_ll_tmr_get();
if (ble_hdr->rxinfo.channel >= BLE_PHY_NUM_DATA_CHANS) {
/*
* We received packet on advertising channel which means this is a legacy
* PDU on 1 Mbps - we do as described above.
*/
earliest_start = adv_rxend + ble_ll_tmr_u2t(1752);
} else {
/*
* The calculations are similar as above.
*
* We received packet on data channel which means this is AUX_ADV_IND
* received on secondary adv channel. We can schedule first packet at
* the earliest after "T_IFS + AUX_CONNECT_REQ + transmitWindowDelay".
* AUX_CONNECT_REQ and transmitWindowDelay times vary depending on which
* PHY we received on.
*
*/
if (ble_hdr->rxinfo.phy == BLE_PHY_1M) {
/* 150 + 352 + 2500 = 3002us */
earliest_start = adv_rxend + ble_ll_tmr_u2t(3002);
} else if (ble_hdr->rxinfo.phy == BLE_PHY_2M) {
/* 150 + 180 + 2500 = 2830us */
earliest_start = adv_rxend + ble_ll_tmr_u2t(2830);
} else if (ble_hdr->rxinfo.phy == BLE_PHY_CODED) {
/* 150 + 2896 + 3750 = 6796us */
earliest_start = adv_rxend + ble_ll_tmr_u2t(6796);
} else {
BLE_LL_ASSERT(0);
}
}
orig_start_time = earliest_start - g_ble_ll_sched_offset_ticks;
#if MYNEWT_VAL(BLE_LL_CONN_STRICT_SCHED)
if (ble_ll_sched_css_is_enabled()) {
OS_ENTER_CRITICAL(sr);
if (!g_ble_ll_conn_css_ref) {
css->period_anchor_ticks = earliest_start;
css->period_anchor_rem_us = 0;
css->period_anchor_idx = 0;
css->period_anchor_slot_idx = connsm->css_slot_idx;
connsm->css_period_idx = 0;
max_delay = connsm->conn_itvl_ticks;
} else {
/* Reference connection may be already at next period if it has
* slot index lower than our, so we first try schedule one period
* earlier since our slot index in that period may not yet have
* passed. This avoids scheduling 1st connection event too far in
* the future, i.e. more than conn interval.
*/
if (connsm->css_slot_idx > css->period_anchor_slot_idx) {
connsm->css_period_idx = css->period_anchor_idx - 1;
} else {
connsm->css_period_idx = css->period_anchor_idx;
}
max_delay = 0;
}
/* Calculate anchor point and move to next period if scheduled too
* early.
*/
connsm->css_period_idx--;
do {
connsm->css_period_idx++;
ble_ll_sched_css_set_conn_anchor(connsm);
sch->start_time =
connsm->anchor_point - g_ble_ll_sched_offset_ticks;
} while (LL_TMR_LT(sch->start_time, orig_start_time));
sch->end_time = connsm->anchor_point;
sch->remainder = connsm->anchor_point_usecs;
OS_EXIT_CRITICAL(sr);
rem_us = sch->remainder;
ble_ll_tmr_add(&sch->end_time, &rem_us, ble_ll_sched_css_get_slot_us());
if (rem_us == 0) {
sch->end_time--;
}
calc_sch = false;
}
#endif
if (calc_sch) {
sch->start_time = earliest_start - g_ble_ll_sched_offset_ticks;
sch->end_time = earliest_start +
ble_ll_tmr_u2t(MYNEWT_VAL(BLE_LL_CONN_INIT_SLOTS) *
BLE_LL_SCHED_USECS_PER_SLOT);
min_win_offset = ble_ll_tmr_u2t(
MYNEWT_VAL(BLE_LL_CONN_INIT_MIN_WIN_OFFSET) *
BLE_LL_SCHED_USECS_PER_SLOT);
sch->start_time += min_win_offset;
sch->end_time += min_win_offset;
sch->remainder = 0;
max_delay = connsm->conn_itvl_ticks - min_win_offset;
}
OS_ENTER_CRITICAL(sr);
rc = ble_ll_sched_insert(sch, max_delay, preempt_none);
if (rc == 0) {
connsm->tx_win_off = ble_ll_tmr_t2u(sch->start_time - orig_start_time) /
BLE_LL_CONN_TX_OFF_USECS;
connsm->anchor_point = sch->start_time + g_ble_ll_sched_offset_ticks;
connsm->anchor_point_usecs = sch->remainder;
connsm->ce_end_time = sch->end_time;
}
OS_EXIT_CRITICAL(sr);
ble_ll_sched_restart();
return rc;
}
/**
* Schedules a peripheral connection for the first time.
*
* Context: Link Layer
*
* @param connsm
*
* @return int
*/
int
ble_ll_sched_conn_periph_new(struct ble_ll_conn_sm *connsm)
{
struct ble_ll_sched_item *sch;
os_sr_t sr;
int rc;
/* Get schedule element from connection */
sch = &connsm->conn_sch;
/* Set schedule start and end times */
/*
* XXX: for now, we dont care about anchor point usecs for the peripheral. It
* does not matter if we turn on the receiver up to one tick before w
* need to. We also subtract one extra tick since the conversion from
* usecs to ticks could be off by up to 1 tick.
*/
sch->start_time = connsm->anchor_point - g_ble_ll_sched_offset_ticks -
ble_ll_tmr_u2t(connsm->periph_cur_window_widening) - 1;
sch->end_time = connsm->ce_end_time;
sch->remainder = 0;
OS_ENTER_CRITICAL(sr);
rc = ble_ll_sched_insert(sch, 0, preempt_any);
OS_EXIT_CRITICAL(sr);
ble_ll_sched_restart();
return rc;
}
#if MYNEWT_VAL(BLE_LL_CFG_FEAT_LL_PERIODIC_ADV) && MYNEWT_VAL(BLE_LL_ROLE_OBSERVER)
/*
* Determines if the schedule item overlaps the currently running schedule
* item. This function cares about connection and sync.
*/
static int
ble_ll_sched_sync_overlaps_current(struct ble_ll_sched_item *sch)
{
uint32_t end_time;
uint8_t state;
state = ble_ll_state_get();
switch (state) {
#if MYNEWT_VAL(BLE_LL_ROLE_CENTRAL) || MYNEWT_VAL(BLE_LL_ROLE_PERIPHERAL)
case BLE_LL_STATE_CONNECTION:
end_time = ble_ll_conn_get_ce_end_time();
break;
#endif
case BLE_LL_STATE_SYNC:
end_time = ble_ll_sync_get_event_end_time();
break;
default:
return 0;
}
return LL_TMR_GT(end_time, sch->start_time);
}
int
ble_ll_sched_sync_reschedule(struct ble_ll_sched_item *sch, uint32_t ww_us)
{
os_sr_t sr;
int rc = 0;
/* Adjust start time to include window widening */
ble_ll_tmr_sub(&sch->start_time, &sch->remainder, ww_us);
OS_ENTER_CRITICAL(sr);
if (ble_ll_sched_sync_overlaps_current(sch)) {
OS_EXIT_CRITICAL(sr);
return -1;
}
rc = ble_ll_sched_insert(sch, 0, preempt_none);
OS_EXIT_CRITICAL(sr);
ble_ll_sched_restart();
return rc;
}
int
ble_ll_sched_sync(struct ble_ll_sched_item *sch)
{
os_sr_t sr;
int rc = 0;
OS_ENTER_CRITICAL(sr);
rc = ble_ll_sched_insert(sch, 0, preempt_none);
OS_EXIT_CRITICAL(sr);
ble_ll_sched_restart();
return rc;
}
#endif
int
ble_ll_sched_adv_new(struct ble_ll_sched_item *sch, ble_ll_sched_adv_new_cb cb,
void *arg)
{
os_sr_t sr;
int rc;
OS_ENTER_CRITICAL(sr);
rc = ble_ll_sched_insert(sch, BLE_LL_SCHED_MAX_DELAY_ANY,
preempt_none);
BLE_LL_ASSERT(rc == 0);
cb(sch->cb_arg, sch->start_time, arg);
OS_EXIT_CRITICAL(sr);
ble_ll_sched_restart();
return rc;
}
int
ble_ll_sched_periodic_adv(struct ble_ll_sched_item *sch, bool first_event)
{
os_sr_t sr;
int rc;
OS_ENTER_CRITICAL(sr);
if (first_event) {
rc = ble_ll_sched_insert(sch, BLE_LL_SCHED_MAX_DELAY_ANY,
preempt_none);
} else {
rc = ble_ll_sched_insert(sch, 0, preempt_any);
}
OS_EXIT_CRITICAL(sr);
ble_ll_sched_restart();
return rc;
}
int
ble_ll_sched_adv_reschedule(struct ble_ll_sched_item *sch,
uint32_t max_delay_ticks)
{
struct ble_ll_sched_item *next;
uint32_t max_end_time;
uint32_t rand_ticks;
os_sr_t sr;
int rc;
max_end_time = sch->end_time + max_delay_ticks;
OS_ENTER_CRITICAL(sr);
/* Try to schedule as early as possible but no later than max allowed delay.
* If succeeded, randomize start time to be within max allowed delay from
* the original start time but make sure it ends before next scheduled item.
*/
rc = ble_ll_sched_insert(sch, max_delay_ticks, preempt_none);
if (rc == 0) {
next = TAILQ_NEXT(sch, link);
if (next) {
if (LL_TMR_LT(next->start_time, max_end_time)) {
max_end_time = next->start_time;
}
rand_ticks = max_end_time - sch->end_time;
} else {
rand_ticks = max_delay_ticks;
}
if (rand_ticks) {
rand_ticks = ble_ll_rand() % rand_ticks;
}
sch->start_time += rand_ticks;
sch->end_time += rand_ticks;
}
OS_EXIT_CRITICAL(sr);
ble_ll_sched_restart();
return rc;
}
int
ble_ll_sched_adv_resched_pdu(struct ble_ll_sched_item *sch)
{
uint8_t lls;
os_sr_t sr;
int rc;
OS_ENTER_CRITICAL(sr);
lls = ble_ll_state_get();
switch(lls) {
#if MYNEWT_VAL(BLE_LL_ROLE_BROADCASTER)
case BLE_LL_STATE_ADV:
OS_EXIT_CRITICAL(sr);
return -1;
#endif
#if MYNEWT_VAL(BLE_LL_ROLE_CENTRAL) || MYNEWT_VAL(BLE_LL_ROLE_PERIPHERAL)
case BLE_LL_STATE_CONNECTION:
OS_EXIT_CRITICAL(sr);
return -1;
#endif
#if MYNEWT_VAL(BLE_LL_CFG_FEAT_LL_PERIODIC_ADV) && MYNEWT_VAL(BLE_LL_ROLE_OBSERVER)
case BLE_LL_STATE_SYNC:
OS_EXIT_CRITICAL(sr);
return -1;
#endif
default:
break;
}
rc = ble_ll_sched_insert(sch, 0, preempt_none);
OS_EXIT_CRITICAL(sr);
ble_ll_sched_restart();
return rc;
}
#if MYNEWT_VAL(BLE_LL_ISO_BROADCASTER)
int
ble_ll_sched_iso_big(struct ble_ll_sched_item *sch, int first, int fixed)
{
os_sr_t sr;
int rc;
OS_ENTER_CRITICAL(sr);
if (first && !fixed) {
rc = ble_ll_sched_insert(sch, BLE_LL_SCHED_MAX_DELAY_ANY, preempt_none);
} else {
/* XXX provide better strategy for preemption */
rc = ble_ll_sched_insert(sch, 0, preempt_any);
}
OS_EXIT_CRITICAL(sr);
ble_ll_sched_restart();
return rc;
}
#endif /* BLE_LL_ISO_BROADCASTER */
/**
* Remove a schedule element
*
* @param sched_type
*
* @return int 0 - removed, 1 - not in the list
*/
int
ble_ll_sched_rmv_elem(struct ble_ll_sched_item *sch)
{
uint8_t first_removed;
os_sr_t sr;
int rc;
BLE_LL_ASSERT(sch);
OS_ENTER_CRITICAL(sr);
first_removed = 0;
if (sch->enqueued) {
if (sch == TAILQ_FIRST(&g_ble_ll_sched_q)) {
first_removed = 1;
}
TAILQ_REMOVE(&g_ble_ll_sched_q, sch, link);
sch->enqueued = 0;
rc = 0;
} else {
rc = 1;
}
if (first_removed) {
ble_ll_sched_q_head_changed();
}
OS_EXIT_CRITICAL(sr);
ble_ll_sched_restart();
return rc;
}
void
ble_ll_sched_rmv_elem_type(uint8_t type, sched_remove_cb_func remove_cb)
{
struct ble_ll_sched_item *first;
struct ble_ll_sched_item *entry;
uint8_t first_removed;
os_sr_t sr;
OS_ENTER_CRITICAL(sr);
first = TAILQ_FIRST(&g_ble_ll_sched_q);
if (first->sched_type == type) {
first_removed = 1;
}
TAILQ_FOREACH(entry, &g_ble_ll_sched_q, link) {
if (entry->sched_type != type) {
continue;
}
TAILQ_REMOVE(&g_ble_ll_sched_q, entry, link);
remove_cb(entry);
entry->enqueued = 0;
}
if (first_removed) {
ble_ll_sched_q_head_changed();
}
OS_EXIT_CRITICAL(sr);
ble_ll_sched_restart();
}
/**
* Executes a schedule item by calling the schedule callback function.
*
* Context: Interrupt
*
* @param sch Pointer to schedule item
*
* @return int 0: schedule item is not over; otherwise schedule item is done.
*/
static int
ble_ll_sched_execute_item(struct ble_ll_sched_item *sch)
{
int rc;
uint8_t lls;
lls = ble_ll_state_get();
ble_ll_trace_u32x3(BLE_LL_TRACE_ID_SCHED, lls, ble_ll_tmr_get(),
sch->start_time);
if (lls == BLE_LL_STATE_STANDBY) {
goto sched;
}
/*
* This is either an advertising event or connection event start. If
* we are scanning or initiating just stop it.
*/
/* We have to disable the PHY no matter what */
ble_phy_disable();
switch (lls) {
#if MYNEWT_VAL(BLE_LL_ROLE_OBSERVER)
case BLE_LL_STATE_SCANNING:
ble_ll_state_set(BLE_LL_STATE_STANDBY);
ble_ll_scan_halt();
break;
#if MYNEWT_VAL(BLE_LL_CFG_FEAT_LL_PERIODIC_ADV)
case BLE_LL_STATE_SYNC:
STATS_INC(ble_ll_stats, sched_state_sync_errs);
ble_ll_sync_halt();
break;
#endif
#if MYNEWT_VAL(BLE_LL_CFG_FEAT_LL_EXT_ADV)
case BLE_LL_STATE_SCAN_AUX:
ble_ll_state_set(BLE_LL_STATE_STANDBY);
ble_ll_scan_aux_halt();
break;
#endif
#endif
#if MYNEWT_VAL(BLE_LL_ROLE_BROADCASTER)
case BLE_LL_STATE_ADV:
STATS_INC(ble_ll_stats, sched_state_adv_errs);
ble_ll_adv_halt();
break;
#endif
#if MYNEWT_VAL(BLE_LL_ROLE_CENTRAL) || MYNEWT_VAL(BLE_LL_ROLE_PERIPHERAL)
case BLE_LL_STATE_CONNECTION:
STATS_INC(ble_ll_stats, sched_state_conn_errs);
ble_ll_conn_event_halt();
break;
#endif
#if MYNEWT_VAL(BLE_LL_ISO_BROADCASTER)
case BLE_LL_STATE_BIG:
ble_ll_iso_big_halt();
break;
#endif
#if MYNEWT_VAL(BLE_LL_EXT)
case BLE_LL_STATE_EXTERNAL:
ble_ll_ext_halt();
break;
#endif
default:
BLE_LL_ASSERT(0);
break;
}
sched:
BLE_LL_ASSERT(sch->sched_cb);
BLE_LL_DEBUG_GPIO(SCHED_ITEM, 1);
rc = sch->sched_cb(sch);
if (rc != BLE_LL_SCHED_STATE_RUNNING) {
BLE_LL_DEBUG_GPIO(SCHED_ITEM, 0);
}
return rc;
}
/**
* Run the BLE scheduler. Iterate through all items on the schedule queue.
*
* Context: interrupt (scheduler)
*
* @return int
*/
static void
ble_ll_sched_run(void *arg)
{
struct ble_ll_sched_item *sch;
BLE_LL_DEBUG_GPIO(SCHED_RUN, 1);
/* Look through schedule queue */
sch = TAILQ_FIRST(&g_ble_ll_sched_q);
if (sch) {
#if (BLE_LL_SCHED_DEBUG == 1)
int32_t dt;
/* Make sure we have passed the start time of the first event */
dt = (int32_t)(ble_ll_tmr_get() - sch->start_time);
if (dt > g_ble_ll_sched_max_late) {
g_ble_ll_sched_max_late = dt;
}
if (dt < g_ble_ll_sched_max_early) {
g_ble_ll_sched_max_early = dt;
}
#endif
/* Remove schedule item and execute the callback */
TAILQ_REMOVE(&g_ble_ll_sched_q, sch, link);
sch->enqueued = 0;
g_ble_ll_sched_q_head_changed = 1;
ble_ll_sched_execute_item(sch);
ble_ll_sched_restart();
}
BLE_LL_DEBUG_GPIO(SCHED_RUN, 0);
}
/**
* Called to determine when the next scheduled event will occur.
*
* If there are not scheduled events this function returns 0; otherwise it
* returns 1 and *next_event_time is set to the start time of the next event.
*
* @param next_event_time
*
* @return int 0: No events are scheduled 1: there is an upcoming event
*/
int
ble_ll_sched_next_time(uint32_t *next_event_time)
{
int rc;
os_sr_t sr;
struct ble_ll_sched_item *first;
rc = 0;
OS_ENTER_CRITICAL(sr);
first = TAILQ_FIRST(&g_ble_ll_sched_q);
if (first) {
*next_event_time = first->start_time;
rc = 1;
}
OS_EXIT_CRITICAL(sr);
return rc;
}
#if MYNEWT_VAL(BLE_LL_CFG_FEAT_LL_EXT_ADV)
int
ble_ll_sched_scan_aux(struct ble_ll_sched_item *sch)
{
os_sr_t sr;
int rc;
OS_ENTER_CRITICAL(sr);
rc = ble_ll_sched_insert(sch, 0, preempt_none);
OS_EXIT_CRITICAL(sr);
ble_ll_sched_restart();
return rc;
}
#endif
#if MYNEWT_VAL(BLE_LL_DTM)
int ble_ll_sched_dtm(struct ble_ll_sched_item *sch)
{
os_sr_t sr;
int rc;
OS_ENTER_CRITICAL(sr);
rc = ble_ll_sched_insert(sch, 0, preempt_any);
OS_EXIT_CRITICAL(sr);
if (rc == 0) {
ble_ll_sched_restart();
}
return rc;
}
#endif
/**
* Stop the scheduler
*
* Context: Link Layer task
*/
void
ble_ll_sched_stop(void)
{
ble_ll_tmr_stop(&g_ble_ll_sched_timer);
}
/**
* Initialize the scheduler. Should only be called once and should be called
* before any of the scheduler API are called.
*
* @return int
*/
int
ble_ll_sched_init(void)
{
BLE_LL_DEBUG_GPIO_INIT(SCHED_ITEM);
BLE_LL_DEBUG_GPIO_INIT(SCHED_RUN);
/*
* Initialize max early to large negative number. This is used
* to determine the worst-case "early" time the schedule was called. Dont
* expect this to be less than -3 or -4.
*/
#if (BLE_LL_SCHED_DEBUG == 1)
g_ble_ll_sched_max_early = -50000;
#endif
/*
* This is the offset from the start of the scheduled item until the actual
* tx/rx should occur, in ticks. We also "round up" to the nearest tick.
*/
g_ble_ll_sched_offset_ticks = ble_ll_tmr_u2t_up(XCVR_TX_SCHED_DELAY_USECS);
/* Initialize cputimer for the scheduler */
ble_ll_tmr_init(&g_ble_ll_sched_timer, ble_ll_sched_run, NULL);
g_ble_ll_sched_q_head_changed = 0;
#if MYNEWT_VAL(BLE_LL_CONN_STRICT_SCHED)
memset(&g_ble_ll_sched_css, 0, sizeof (g_ble_ll_sched_css));
#if !MYNEWT_VAL(BLE_LL_CONN_STRICT_SCHED_FIXED)
g_ble_ll_sched_css.slot_us = MYNEWT_VAL(BLE_LL_CONN_STRICT_SCHED_SLOT_US);
g_ble_ll_sched_css.period_slots = MYNEWT_VAL(BLE_LL_CONN_STRICT_SCHED_PERIOD_SLOTS);
#endif
#if !MYNEWT_VAL(BLE_LL_HCI_VS_CONN_STRICT_SCHED)
g_ble_ll_sched_css.enabled = 1;
#endif
#endif
return 0;
}
#if MYNEWT_VAL(BLE_LL_CONN_STRICT_SCHED)
#if !MYNEWT_VAL(BLE_LL_CONN_STRICT_SCHED_FIXED)
void
ble_ll_sched_css_set_params(uint32_t slot_us, uint32_t period_slots)
{
g_ble_ll_sched_css.slot_us = slot_us;
g_ble_ll_sched_css.period_slots = period_slots;
}
#endif
void
ble_ll_sched_css_set_enabled(uint8_t enabled)
{
g_ble_ll_sched_css.enabled = enabled;
}
void
ble_ll_sched_css_update_anchor(struct ble_ll_conn_sm *connsm)
{
struct ble_ll_sched_css *css = &g_ble_ll_sched_css;
if (!g_ble_ll_conn_css_ref) {
g_ble_ll_conn_css_ref = connsm;
css->period_anchor_ticks = connsm->anchor_point;
css->period_anchor_rem_us = connsm->anchor_point_usecs;
}
}
void
ble_ll_sched_css_set_conn_anchor(struct ble_ll_conn_sm *connsm)
{
struct ble_ll_sched_css *css = &g_ble_ll_sched_css;
int8_t period_diff;
int16_t slot_diff;
int32_t diff;
period_diff = connsm->css_period_idx - css->period_anchor_idx;
slot_diff = connsm->css_slot_idx - css->period_anchor_slot_idx;
diff = (period_diff * ble_ll_sched_css_get_period_slots() + slot_diff) *
ble_ll_sched_css_get_slot_us();
connsm->anchor_point = css->period_anchor_ticks;
connsm->anchor_point_usecs = css->period_anchor_rem_us;
if (diff < 0) {
ble_ll_tmr_sub(&connsm->anchor_point, &connsm->anchor_point_usecs,
-diff);
} else if (diff > 0) {
ble_ll_tmr_add(&connsm->anchor_point, &connsm->anchor_point_usecs,
diff);
}
}
#if !MYNEWT_VAL(BLE_LL_CONN_STRICT_SCHED_FIXED)
inline bool
ble_ll_sched_css_is_enabled(void)
{
return g_ble_ll_sched_css.enabled;
}
inline uint32_t
ble_ll_sched_css_get_slot_us(void)
{
return g_ble_ll_sched_css.slot_us;
}
inline uint32_t
ble_ll_sched_css_get_period_slots(void)
{
return g_ble_ll_sched_css.period_slots;
}
inline uint32_t
ble_ll_sched_css_get_conn_interval_us(void)
{
return ble_ll_sched_css_get_period_slots() *
ble_ll_sched_css_get_slot_us() /
BLE_LL_CONN_ITVL_USECS;
}
#endif
#endif