cache.c

pebble

/* 
 * Copyright 1999, 2000, 2001, 2002 Lucent Technologies Inc.
 * All Rights Reserved.
 * Information Sciences Research Center, Bell Labs.
 *
 * LUCENT TECHNOLOGIES DOES NOT CLAIM MERCHANTABILITY OF THIS SOFTWARE 
 * OR THE SUITABILITY OF THIS SOFTWARE FOR ANY PARTICULAR PURPOSE. The
 * software is provided "as is" without expressed or implied warranty 
 * of any kind.
 *
 * These notices must be retained in any copies of any part of this
 * software.
 *
 */

/*
 * Cache testing
 *
 * Runs in user mode with interrupts enabled.
 */

#include "pebble.h"
#include "string.h"
#include "machine/cpu.h"
#ifndef	Cobalt
#include "sbd.h"
#include "rtc.h"
#else
#include "qube.h"
#endif
#include "mem.h"
#include "time.h"

#ifndef Cobalt		/* !Cobalt */

#include "perfcount.h"

#define	MEM_START	0
#define	MEM_SIZE	4*1024*1024
#define	SMALLEST_SIZE	8*1024
#define	CACHE_LINE	32

/* driver initialization thread */
int main()
{
	int x;	/* debug */
	volatile char *p, *end;
	int i, ntimes;
	int size, sum;
	int perf_ix;
	uint perf_count;
	uvlong start_time, elapsed;

	printf("cache test. asid=%d stack at %p\n", get_asid(), &x);

        /* verify that we are running in user mode with interrupts enabled */ 
        if (!check_psw(1,1)) {
                printf("cache: invalid processor status: %08lx\n", get_psw());
                task_exit(1);
        }

	for (size = SMALLEST_SIZE; size <= MEM_SIZE; size <<= 1) {
		printf("=============\n");
		printf("testing uncached memory scan of %d bytes area\n", size);

		ntimes = MEM_SIZE / size;
		sum = 0;

		/* initial scan to fill the cache */
		p = (volatile char *)(IO_BASE + MEM_START);
		end = p + size;
		for (; p < end; p += CACHE_LINE)
			sum += *p;

		for (perf_ix = 0; perf_vec[perf_ix].name != NULL; perf_ix++) {
			set_perf_ctrl(perf_vec[perf_ix].ctrl);
			start_time = hrtime();

			for (i = 0; i < ntimes; i++) {
				p = (volatile char *)(IO_BASE + MEM_START);
				for (; p < end; p += CACHE_LINE)
					sum += *p;
			}

			perf_count = get_perf_count();
			elapsed = 2 * (hrtime() - start_time);

			printf("%s: %d\telapsed time: %d cycles (%d cycles/access) sum=%d\n",
				perf_vec[perf_ix].name, perf_count,
				(int)elapsed,
				(int)(elapsed / (MEM_SIZE/CACHE_LINE)),
				sum);
		}
	}

	/*
	 * return to initialization code.
	 * cannot just "return", since the startup code (crt0.S) calls
	 * exit when main routine terminates.
	 */
	call_portal(SYS_RTN_RPC);
	return(1);
}

#else	/* !Cobalt */

/* driver initialization thread */
int main()
{
	/*
	 * return to initialization code.
	 * cannot just "return", since the startup code (crt0.S) calls
	 * exit when main routine terminates.
	 */
	call_portal(SYS_RTN_RPC);
	return(1);
}
#endif