Files
UHD-Fairwaves/zpu/lib/time64.c

94 lines
2.4 KiB
C

/*
* Copyright 2017 Alexander Chemeris <Alexander.Chemeris@fairwaves.co>
*
* 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 3 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, see <http://www.gnu.org/licenses/>.
*/
#include "memory_map.h"
/* printf headers */
//#include "nonstdio.h"
/* standard headers */
#include <stddef.h>
//#include <stdlib.h>
//#include <string.h>
#include <stdbool.h>
#include <limits.h>
#define UINT32_MAX UINT_MAX
void
time64_read(uint32_t *secs, uint32_t *ticks)
{
uint32_t cur_secs, cur_secs2;
cur_secs = readback_mux->time64_secs_rb;
*ticks = readback_mux->time64_ticks_rb;
cur_secs2 = readback_mux->time64_secs_rb;
/* Check for seconds wrap */
if (cur_secs2 != cur_secs) {
/* Decide which seconds reading is correct.
* Here we assume that we're reading fast and time between
* two readings is negligible compared to a 32-bit counter
* wrap time.
*/
if (*ticks < UINT32_MAX/2) {
/* First half of the time - wrap has just happened */
*secs = cur_secs2;
} else {
/* Second half - wrap has not happened yet */
*secs = cur_secs;
}
}
}
int
time64_compare(uint32_t secs1, uint32_t ticks1,
uint32_t secs2, uint32_t ticks2)
{
if (secs1 == secs2) {
if (ticks1 < ticks2) {
return -1;
} else if (ticks1 == ticks2) {
return 0;
} else {
return 1;
}
} else if (secs1 < secs2) {
return -1;
} else {
return 1;
}
}
void
time64_add_ticks(uint32_t *secs, uint32_t *ticks,
uint32_t ticks2)
{
if (UINT32_MAX - *ticks > ticks2) {
*secs += 1;
}
*ticks += ticks2;
}
bool
time64_is_elapsed(uint32_t secs1, uint32_t ticks1,
uint32_t secs2, uint32_t ticks2,
uint32_t ticks_elapsed)
{
time64_add_ticks(&secs1, &ticks1, ticks_elapsed);
return time64_compare(secs1, ticks1, secs2, ticks2) >= 0;
}