[src/trunk]: src/sys/arch/xen/xen get the time from Xen

[cl <cl%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/1bb057507da7
branches:  trunk
changeset: 565519:1bb057507da7
user:      cl <cl%NetBSD.org@localhost>
date:      Sat Apr 10 23:50:23 2004 +0000

description:
get the time from Xen

diffstat:

 sys/arch/xen/xen/clock.c |  99 +++++++++++++++++++++++++++++++++++++----------
 1 files changed, 77 insertions(+), 22 deletions(-)

diffs (155 lines):

diff -r 2a32ce2169b2 -r 1bb057507da7 sys/arch/xen/xen/clock.c
--- a/sys/arch/xen/xen/clock.c  Sat Apr 10 23:47:24 2004 +0000
+++ b/sys/arch/xen/xen/clock.c  Sat Apr 10 23:50:23 2004 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: clock.c,v 1.1 2004/03/11 21:44:08 cl Exp $     */
+/*     $NetBSD: clock.c,v 1.2 2004/04/10 23:50:23 cl Exp $     */
 
 /*
  *
@@ -33,7 +33,7 @@
 
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: clock.c,v 1.1 2004/03/11 21:44:08 cl Exp $");
+__KERNEL_RCSID(0, "$NetBSD: clock.c,v 1.2 2004/04/10 23:50:23 cl Exp $");
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -45,19 +45,87 @@
 #include <machine/hypervisor.h>
 #include <machine/events.h>
 
+#include <dev/clock_subr.h>
+
+#include "config_time.h"               /* for CONFIG_TIME */
+
 static int xen_timer_handler(void *, struct trapframe *);
 
+/* These are peridically updated in shared_info, and then copied here. */
+static unsigned long shadow_tsc_stamp;
+static uint64_t shadow_system_time;
+static unsigned long shadow_time_version;
+static struct timeval shadow_tv;
+
+static int timeset;
+
+/*
+ * Reads a consistent set of time-base values from Xen, into a shadow data
+ * area.  Must be called at splclock.
+ */
+static void get_time_values_from_xen(void)
+{
+       do {
+               shadow_time_version = HYPERVISOR_shared_info->time_version2;
+               __insn_barrier();
+               shadow_tv.tv_sec = HYPERVISOR_shared_info->wc_sec;
+               shadow_tv.tv_usec = HYPERVISOR_shared_info->wc_usec;
+               shadow_tsc_stamp = HYPERVISOR_shared_info->tsc_timestamp;
+               shadow_system_time = HYPERVISOR_shared_info->system_time;
+               __insn_barrier();
+       } while (shadow_time_version != HYPERVISOR_shared_info->time_version1);
+}
+
 void
-inittodr(base)
-       time_t base;
+inittodr(time_t base)
 {
-       /* printf("inittodr %08lx\n", base); */
+       int s;
+
+       /*
+        * if the file system time is more than a year older than the
+        * kernel, warn and then set the base time to the CONFIG_TIME.
+        */
+       if (base && base < (CONFIG_TIME-SECYR)) {
+               printf("WARNING: preposterous time in file system\n");
+               base = CONFIG_TIME;
+       }
+
+       s = splclock();
+       get_time_values_from_xen();
+       splx(s);
+
+       time.tv_usec = shadow_tv.tv_usec;
+       time.tv_sec = shadow_tv.tv_sec + rtc_offset * 60;
+#ifdef DEBUG_CLOCK
+       printf("readclock: %ld (%ld)\n", time.tv_sec, base);
+#endif
+       if (base != 0 && base < time.tv_sec - 5*SECYR)
+               printf("WARNING: file system time much less than clock time\n");
+       else if (base > time.tv_sec + 5*SECYR) {
+               printf("WARNING: clock time much less than file system time\n");
+               printf("WARNING: using file system time\n");
+               goto fstime;
+       }
+
+       timeset = 1;
+       return;
+
+fstime:
+       timeset = 1;
+       time.tv_sec = base;
+       printf("WARNING: CHECK AND RESET THE DATE!\n");
 }
 
 void
 resettodr()
 {
-       /* panic("resettodr"); */
+
+       /*
+        * We might have been called by boot() due to a crash early
+        * on.  Don't reset the clock chip in this case.
+        */
+       if (!timeset)
+               return;
 }
 
 void
@@ -80,14 +148,14 @@
 xen_delay(int n)
 {
        int k;
-       /* panic("xen_delay %d\n", n); */
+
        for (k = 0; k < 10 * n; k++);
 }
 
 void
 xen_microtime(struct timeval *tv)
 {
-       panic("xen_microtime %p\n", tv);
+       printf("xen_microtime %p\n", tv);
 }
 
 void
@@ -102,26 +170,13 @@
 static int
 xen_timer_handler(void *arg, struct trapframe *regs)
 {
-#if 0
-       static int hztest;
 
-       if ((hztest--) == 0) {
-               hztest = hz - 1;
-               printf("ping!!! hz=%d regs %p level %d ipending %08x\n", hz,
-                   regs, cpu_info_primary.ci_ilevel,
-                   cpu_info_primary.ci_ipending);
-       }
-#endif
-
-       /* printf("timer event\n"); */
        hardclock((struct clockframe *)regs);
 
        return 0;
 }
 
 void
-setstatclockrate(arg)
-       int arg;
+setstatclockrate(int arg)
 {
-       /* printf("setstatclockrate\n"); */
 }