Fujitsu Fujitsu SPARC64 V manual Counter Event Selection and Start, Counter Stop and Read

/* clear pics without altering sl/su values */ pic_init = 0x0;

pcr = rd_pcr();

pcr.ulro = 0x1; /* don’t change su/sl on write */

pcr.ovf = 0x0; /* clear overflow bits also */ pcr.ut = 0x0;

pcr.st = 0x0; /* disable counts for good measure */ for (i=0; i<=pcr.nc; i++) {

/* select the pic to be written */ pcr.sc = i;

wr_pcr(pcr);

wr_pic(pic_init);/* clear pic i */

}

Counter Event Selection and Start

Counter events are selected through PCR.SC and PCR.SU/PCR.SL fields. The following pseudocode selects events and enables counters (assuming privileged access):

pcr.ut = 0x0; /* initially disable user counts */

pcr.st = 0x0; /* initially disable system counts */

pcr.ulro = 0x0; /* make sure read-only disabled */

pcr.ovro = 0x1; /* do not modify overflow bits */ /* select the events without enabling counters */ for(i=0; i<=pcr.nc; i++) {

pcr.sc = i;

pcr.sl = select an event; pcr.su = select an event; wr_pcr(pcr);

}

/* start counting */ pcr.ut = 0x1; pcr.st = 0x1;

pcr.ulro = 0x1; /* for not changing the last su/sl */ /* resetting of overflow bits can be done here */ wr_pcr(pcr);

Counter Stop and Read

The following pseudocode disables and reads counters (assuming privileged access):

pcr.ut	= 0x0;			/* disable		counts */
pcr.st	= 0x0;			/* disable		counts */
pcr.ulro		=	0x1;	/*	enable	sl/su read-only */
pcr.ovro		=	0x1;	/*	do not	modify overflow bits */

202 SPARC JPS1 Implementation Supplement: Fujitsu SPARC64 V • Release 1.0, 1 July 2002