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/* oneshot_test
Victor Yodaiken (c) 1999, Released under the GPL.
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <asm/ptrace.h>
#include <linux/rtl.h>
#include <asm/io.h>
#include <linux/cons.h>
#include <rtl_sync.h>
#include <rtl_fifo.h>
#include <rtl_time.h>
#include <rtl_core.h>
#include "common.h"
static int min_interval = 40000;
/* Knuth's algorithm for random numbers */
static unsigned long seed = 1;
unsigned long ulrand (void)
{
return (seed *= 69069);
}
clockid_t clock;
void shutdown(void);
static int shutdown_flag = 0;
static unsigned long max_diff = 0;
static unsigned long min_diff = 0x7fffffff;
static unsigned long last_time = 0;
static unsigned long count = 0;
#define FIFO_NUM 0
void handler(struct pt_regs *p) {
unsigned long x,diff,t;
struct sample samp;
switch(shutdown_flag){
case 0:
x = gethrtime();
if (last_time) {
diff = x - last_time; /* mod 2^32 */
if(diff > max_diff) max_diff=diff;
if(diff < min_diff) min_diff = diff;
}
if(count++ > 10000){
count = 0;
samp.min = timespec_from_ns(min_diff);
samp.max = timespec_from_ns(max_diff);
rtf_put(FIFO_NUM, &samp, sizeof(samp));
max_diff = 0;
min_diff = 0x7fffffff;
}
t = ulrand() % min_interval + min_interval;
clock->settimer(clock, t);
last_time = gethrtime() + t;
break;
case 1:
shutdown_flag = 2;
default: /* do nothing */
}
return;
}
int fifo_size=4000;
int init_module(void)
{
int old_irq_state;
int fifo_status;
rtf_destroy(FIFO_NUM); /* just in case someone else is using!*/
fifo_status = rtf_create(FIFO_NUM, fifo_size);
if (fifo_status) {
printk("RTL measurement test fail. fifo_status=%d\n",fifo_status);
return -1;
}
printk("Starting Timer measurement module: numbers in nanoseconds!\n");
clock = rtl_getbestclock (rtl_getcpuid());
if (!clock || rtl_setclockhandler(clock, handler)) {
printk("Can't get clock\n");
rtf_destroy(FIFO_NUM);
return -1;
}
printk("Requested timer and got %x\n",(unsigned int)clock);
rtl_no_interrupts(old_irq_state);
clock->init(clock);
clock->settimermode(clock, RTL_CLOCK_MODE_ONESHOT);
clock->settimer(clock, 10000);
clock->settimermode(clock, RTL_CLOCK_MODE_ONESHOT);
clock->settimer(clock, 10000);
rtl_restore_interrupts(old_irq_state);
return 0;
}
void shutdown(){
int old_irq_state;
rtl_no_interrupts(old_irq_state);
clock->uninit(clock);
rtf_destroy(FIFO_NUM);
rtl_restore_interrupts(old_irq_state);
}
void cleanup_module(void)
{
int timeout = 100000;
shutdown_flag = 1;
while((shutdown_flag==1) && timeout--);
/* so it's kinda sloppy, wait for timeout or for
interrupt routine to ack shutdown, whatever comes
first */
shutdown();
}
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