ATI temperature controller

tempmon.c

#include<stdio.h>
#include<stdlib.h>
#include<unistd.h>
#include<math.h>
#include<string.h>
#include<limits.h>

#define NADAPTERS 4
static const int MAXCLOCK = 950;
static const int MINCLOCK = 500;
static const int STARTCLOCK = 800;
static const float TARGET = 95;
static const float TOL = 2;
static const float P = 5;
static const int LOADTHRESH = 95;
static const int SLEEPTIME = 5;

typedef struct adapt adapt;
struct adapt{
	float temp;
	int clock;
	int load;
};

adapt adapters[NADAPTERS];

int
parse_int(char *str, char *buf)
{
	char *num, *end;
	int n;
	n = strlen(str);
	if(strncmp(buf, str, n)){
		fprintf(stderr, "Error parsing string: %s\n", buf);
		return INT_MIN;
	}
	num = buf + n;
	for(end = num; *end <= '9' && *end >= '0' && end != '\0'; end++);
	*end = '\0';
	return atoi(num);
}

int
fetch(void)
{
	FILE *ati;
	char buf[1024];
	int tiktok;
	char *num, *end;
	int id = -1;

	/* Read in the temperatures */

	if((ati = popen("aticonfig --adapter=all --odgt", "r")) == NULL){
		fprintf(stderr, "Error executing aticonfig to fetch temperatures\n");
		return -1;
	}

	tiktok = 0;
	while(fgets(buf, sizeof(buf) - 1, ati) != NULL){
		switch(tiktok){
			case 0:
				break;
			case 1:
				if((id = parse_int("Adapter ", buf)) == INT_MIN){
					pclose(ati);
					return -1;
				}
				break;
			case 2:
				if(id < 0 || id >= NADAPTERS)
					abort();
				if(strncmp(buf, "            Sensor 0: Temperature - ", 36)){
					fprintf(stderr, "Error parsing temperature string: %s\n", buf);
					pclose(ati);
					return -1;
				}
				num = buf + 36;
				for(end = num; *end != ' ' && end != '\0'; end++);
				*end = '\0';
				adapters[id].temp = atof(num);
				break;
			default:
				abort();
		}
		tiktok = (1 + tiktok) % 3;
	}
	pclose(ati);


	/* Now the clock speeds and workloads */
	if((ati = popen("aticonfig --adapter=all --odgc", "r")) == NULL){
		fprintf(stderr, "Error executing aticonfig to fetch clocks\n");
		return -1;
	}

	tiktok = 0;
	while(fgets(buf, sizeof(buf) - 1, ati) != NULL){
		switch(tiktok){
			case 1:
				if((id = parse_int("Adapter ", buf)) == INT_MIN){
					pclose(ati);
					return -1;
				}
				break;
			case 3:
				if(id < 0 || id >= NADAPTERS)
					abort();
				adapters[id].clock = parse_int("           Current Clocks :    ", buf);
				break;
			case 6:
				if(id < 0 || id >= NADAPTERS)
					abort();
				if((adapters[id].load = parse_int("                 GPU load :    ", buf)) == INT_MIN){
					pclose(ati);
					return -1;
				}
				break;
			default:
				break;
		}
		tiktok = (1 + tiktok) % 7;
	}
	pclose(ati);

}

int
setclock(int i)
{
	char buf[512];
	sprintf(buf, "aticonfig --adapter=%d --odsc=%d,%d > /dev/null", i, adapters[i].clock, adapters[i].clock - 100);
	if(system(buf) != 0){
		fprintf(stderr, "Error setting adapter %d to %d: \n", i, adapters[i].clock, buf);
		return -1;
	}
	return 0;
}

int
main(int argc, char **argv)
{
	int i;
	float error;

	for(;;){
		if(!fetch()){
			for(i = 0; i < NADAPTERS; i++){
				error = TARGET - adapters[i].temp;
				if(fabs(error) > TOL && (error < 0 || adapters[i].load > LOADTHRESH)){
					if(error > 0 && adapters[i].clock >= MAXCLOCK)
						continue;
					adapters[i].clock += P * error;
					if(adapters[i].clock > MAXCLOCK)
						adapters[i].clock = MAXCLOCK;
					if(adapters[i].clock < MINCLOCK)
						adapters[i].clock = MINCLOCK;
					printf("%d,%d: %g %d\n", i, adapters[i].clock, adapters[i].temp, adapters[i].load);
					setclock(i);
				}
			
			}
		}else
			fprintf(stderr, "Fetch error.  Skipping.\n");
		sleep(SLEEPTIME);
	}
	return 0;
}