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/*
* Copyright (C) 2006-2009 Free Software Foundation
*
* This program is free software ; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation ; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY ; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with the program ; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <sys/types.h>
#include <mach/mach_types.h>
#include <kern/mach_clock.h>
#include <mach/xen.h>
#include <machine/xen.h>
#include <machine/spl.h>
#include <machine/ipl.h>
#include <mach/machine/eflags.h>
#include <xen/evt.h>
#include "time.h"
#include "store.h"
static unsigned64_t lastnsec;
/* 2^64 nanoseconds ~= 500 years */
static unsigned64_t hyp_get_stime(void) {
unsigned32_t version;
unsigned64_t cpu_clock, last_cpu_clock, delta, system_time;
unsigned64_t delta_high, delta_low;
unsigned32_t mul;
signed8_t shift;
volatile struct vcpu_time_info *time = &hyp_shared_info.vcpu_info[0].time;
do {
version = time->version;
rmb();
cpu_clock = hyp_cpu_clock();
last_cpu_clock = time->tsc_timestamp;
system_time = time->system_time;
mul = time->tsc_to_system_mul;
shift = time->tsc_shift;
rmb();
} while (version != time->version);
delta = cpu_clock - last_cpu_clock;
if (shift < 0)
delta >>= -shift;
else
delta <<= shift;
delta_high = delta >> 32;
delta_low = (unsigned32_t) delta;
return system_time + ((delta_low * (unsigned64_t) mul) >> 32)
+ (delta_high * (unsigned64_t) mul);
}
unsigned64_t hyp_get_time(void) {
unsigned32_t version;
unsigned32_t sec, nsec;
do {
version = hyp_shared_info.wc_version;
rmb();
sec = hyp_shared_info.wc_sec;
nsec = hyp_shared_info.wc_nsec;
rmb();
} while (version != hyp_shared_info.wc_version);
return sec*1000000000ULL + nsec + hyp_get_stime();
}
static void hypclock_intr(int unit, int old_ipl, void *ret_addr, struct i386_interrupt_state *regs) {
unsigned64_t nsec, delta;
if (!lastnsec)
return;
nsec = hyp_get_stime();
if (nsec < lastnsec) {
printf("warning: nsec 0x%08lx%08lx < lastnsec 0x%08lx%08lx\n",(unsigned long)(nsec>>32), (unsigned long)nsec, (unsigned long)(lastnsec>>32), (unsigned long)lastnsec);
nsec = lastnsec;
}
delta = nsec-lastnsec;
lastnsec += (delta/1000)*1000;
hypclock_machine_intr(old_ipl, ret_addr, regs, delta);
/* 10ms tick rest */
hyp_do_set_timer_op(hyp_get_stime()+10*1000*1000);
#if 0
char *c = hyp_store_read(0, 1, "control/shutdown");
if (c) {
static int go_down = 0;
if (!go_down) {
printf("uh oh, shutdown: %s\n", c);
go_down = 1;
/* TODO: somehow send startup_reboot notification to init */
if (!strcmp(c, "reboot")) {
/* this is just a reboot */
}
}
}
#endif
}
extern struct timeval time;
int
readtodc(tp)
u_int *tp;
{
unsigned64_t t = hyp_get_time();
u_int n = t / 1000000000;
*tp = n;
return(0);
}
int
writetodc()
{
/* Not allowed in Xen */
return(-1);
}
void
clkstart()
{
evtchn_port_t port = hyp_event_channel_bind_virq(VIRQ_TIMER, 0);
hyp_evt_handler(port, hypclock_intr, 0, SPLHI);
/* first clock tick */
clock_interrupt(0, 0, 0);
lastnsec = hyp_get_stime();
/* 10ms tick rest */
hyp_do_set_timer_op(hyp_get_stime()+10*1000*1000);
}
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