diff options
Diffstat (limited to 'src/target/firmware/layer1/tdma_sched.c')
| -rw-r--r-- | src/target/firmware/layer1/tdma_sched.c | 163 |
1 files changed, 163 insertions, 0 deletions
diff --git a/src/target/firmware/layer1/tdma_sched.c b/src/target/firmware/layer1/tdma_sched.c new file mode 100644 index 00000000..097e9a42 --- /dev/null +++ b/src/target/firmware/layer1/tdma_sched.c @@ -0,0 +1,163 @@ +/* TDMA Scheduler Implementation */ + +/* (C) 2010 by Harald Welte <laforge@gnumonks.org> + * + * All Rights Reserved + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + * + */ + +#include <stdint.h> +#include <stdio.h> +#include <string.h> + +#include <debug.h> +#include <gsm.h> + +#include <layer1/tdma_sched.h> +#include <layer1/sync.h> + +#include <calypso/dsp.h> + +static uint8_t wrap_bucket(uint8_t offset) +{ + uint16_t bucket; + + bucket = (l1s.tdma_sched.cur_bucket + offset) + % ARRAY_SIZE(l1s.tdma_sched.bucket); + + return bucket; +} + +/* Schedule an item at 'frame_offset' TDMA frames in the future */ +int tdma_schedule(uint8_t frame_offset, tdma_sched_cb *cb, uint16_t p1, uint16_t p2) +{ + struct tdma_scheduler *sched = &l1s.tdma_sched; + uint8_t bucket_nr = wrap_bucket(frame_offset); + struct tdma_sched_bucket *bucket = &sched->bucket[bucket_nr]; + struct tdma_sched_item *sched_item; + + if (bucket->num_items >= ARRAY_SIZE(bucket->item)) { + puts("tdma_schedule bucket overflow\n"); + return -1; + } + + sched_item = &bucket->item[bucket->num_items++]; + + sched_item->cb = cb; + sched_item->p1 = p1; + sched_item->p2 = p2; + + return 0; +} + +/* Schedule a set of items starting from 'frame_offset' TDMA frames in the future */ +int tdma_schedule_set(uint8_t frame_offset, const struct tdma_sched_item *item_set, + uint8_t num_items) +{ + struct tdma_scheduler *sched = &l1s.tdma_sched; + uint8_t bucket_nr = wrap_bucket(frame_offset); + int i; + + for (i = 0; i < num_items; i++) { + const struct tdma_sched_item *sched_item = &item_set[i]; + struct tdma_sched_bucket *bucket = &sched->bucket[bucket_nr]; + + if (sched_item->cb == NULL) { + /* advance to next bucket (== TDMA frame) */ + bucket_nr = wrap_bucket(++frame_offset); + continue; + } + /* check for bucket overflow */ + if (bucket->num_items >= ARRAY_SIZE(bucket->item)) { + puts("tdma_schedule bucket overflow\n"); + return -1; + } + /* copy the item from the set into the current bucket item position */ + memcpy(&bucket->item[bucket->num_items++], sched_item, sizeof(*sched_item)); + } + + return num_items; +} + +/* Execute pre-scheduled events for current frame */ +int tdma_sched_execute(void) +{ + struct tdma_scheduler *sched = &l1s.tdma_sched; + struct tdma_sched_bucket *bucket; + uint8_t next_bucket; + int i, num_events = 0; + + /* determine current bucket */ + bucket = &sched->bucket[sched->cur_bucket]; + + /* iterate over items in this bucket and call callback function */ + for (i = 0; i < bucket->num_items; i++) { + struct tdma_sched_item *item = &bucket->item[i]; + int rc; + + num_events++; + + rc = item->cb(item->p1, item->p2); + if (rc < 0) { + printf("Error %d during processing of item %u of bucket %u\n", + rc, i, sched->cur_bucket); + return rc; + } + /* if the cb() we just called has scheduled more items for the + * current TDMA, bucket->num_items will have increased and we + * will simply continue to execute them as intended */ + } + + /* clear/reset the bucket */ + bucket->num_items = 0; + + /* advance to the next bucket */ + next_bucket = wrap_bucket(1); + sched->cur_bucket = next_bucket; + + /* return number of items that we called */ + return num_events; +} + +void tdma_sched_reset(void) +{ + struct tdma_scheduler *sched = &l1s.tdma_sched; + unsigned int bucket_nr; + + for (bucket_nr = 0; bucket_nr < ARRAY_SIZE(sched->bucket); bucket_nr++) { + struct tdma_sched_bucket *bucket = &sched->bucket[bucket_nr]; + /* current bucket will be reset by iteration code above! */ + if (bucket_nr != sched->cur_bucket) + bucket->num_items = 0; + } + + /* Don't reset cur_bucket, as it would upset the bucket iteration code + * in tdma_sched_execute() */ +} + +void tdma_sched_dump(void) +{ + unsigned int i; + + printf("\n(%2u)", l1s.tdma_sched.cur_bucket); + for (i = 0; i < ARRAY_SIZE(l1s.tdma_sched.bucket); i++) { + int bucket_nr = wrap_bucket(i); + struct tdma_sched_bucket *bucket = &l1s.tdma_sched.bucket[bucket_nr]; + printf("%u:", bucket->num_items); + } + putchar('\n'); +} |