/*--------------------------------------------------------------- * Copyright (c) 2017 * Broadcom Corporation * All Rights Reserved. *--------------------------------------------------------------- * Permission is hereby granted, free of charge, to any person * obtaining a copy of this software and associated * documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the * rights to use, copy, modify, merge, publish, distribute, * sublicense, and/or sell copies of the Software, and to permit * persons to whom the Software is furnished to do * so, subject to the following conditions: * * * Redistributions of source code must retain the above * copyright notice, this list of conditions and * the following disclaimers. * * * Redistributions in binary form must reproduce the above * copyright notice, this list of conditions and the following * disclaimers in the documentation and/or other materials * provided with the distribution. * * * Neither the name of Broadcom Coporation, * nor the names of its contributors may be used to endorse * or promote products derived from this Software without * specific prior written permission. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND * NONINFRINGEMENT. IN NO EVENT SHALL THE CONTIBUTORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, * ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. * ________________________________________________________________ * * isochronous.c * Suppport for isochonronous traffic testing * * by Robert J. McMahon (rjmcmahon@rjmcmahon.com, bob.mcmahon@broadcom.com) * ------------------------------------------------------------------- */ #include "headers.h" #include "Timestamp.hpp" #include "isochronous.hpp" #include "delay.h" using namespace Isochronous; // Produce a frame counter with frequency in units of frames per second, e.g. 60 fps FrameCounter::FrameCounter(double value) : frequency(value) { period = (unsigned int) (1000000 / frequency); lastcounter = 0; } unsigned int FrameCounter::get(long *ticks_remaining) { Timestamp sampleTime; // Constructor will initialize timestamp to now long usecs = -startTime.subUsec(sampleTime); // This will round towards zero per the integer divide unsigned int counter = (unsigned int) (usecs / period); if (ticks_remaining) { // figure out how many usecs before the next frame counter tick // the caller can use this to delay until the next tick *ticks_remaining = ((counter + 1) * period) - usecs; } return(counter + 1); // Frame counter for packets starts at 1 } unsigned int FrameCounter::wait_tick(void) { long remaining; unsigned int framecounter; if (!lastcounter) { reset(); framecounter = 1; } else { framecounter = get(&remaining); if ((framecounter - lastcounter) > 1) slip++; delay_loop(remaining); framecounter ++; } lastcounter = framecounter; return(framecounter); } unsigned int FrameCounter::period_us(void) { return(period); } void FrameCounter::reset(void) { period = (1000000 / frequency); startTime.setnow(); } unsigned int FrameCounter::wait_sync(long sec, long usec) { long remaining; unsigned int framecounter; startTime.set(sec, usec); framecounter = get(&remaining); delay_loop(remaining); reset(); framecounter = 1; lastcounter = 1; return(framecounter); } long FrameCounter::getSecs( void ) { return startTime.getSecs(); } long FrameCounter::getUsecs( void ) { return startTime.getUsecs(); }