| To: | "Tian, Kevin" <kevin.tian@xxxxxxxxx>, Keir Fraser <keir@xxxxxxxxxxxxx>, <xen-devel@xxxxxxxxxxxxxxxxxxx> |
|---|---|
| Subject: | Re: [Xen-devel] RE: A question about PIT platform timer |
| From: | Keir Fraser <keir@xxxxxxxxxxxxx> |
| Date: | 2006年12月11日 14:35:35 +0000 |
| Delivery-date: | 2006年12月11日 06:35:43 -0800 |
| Envelope-to: | www-data@xxxxxxxxxxxxxxxxxx |
| In-reply-to: | <D470B4E54465E3469E2ABBC5AFAC390F9E0FA2@xxxxxxxxxxxxxxxxxxxxxxxxxxxx> |
| List-help: | <mailto:xen-devel-request@lists.xensource.com?subject=help> |
| List-id: | Xen developer discussion <xen-devel.lists.xensource.com> |
| List-post: | <mailto:xen-devel@lists.xensource.com> |
| List-subscribe: | <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=subscribe> |
| List-unsubscribe: | <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe> |
| Sender: | xen-devel-bounces@xxxxxxxxxxxxxxxxxxx |
| Thread-index: | AccdA44RYK8xaKWxSleokF0BH7qTYQABEEJ1AAU7KvAABTijSQ== |
| Thread-topic: | [Xen-devel] RE: A question about PIT platform timer |
| User-agent: | Microsoft-Entourage/11.2.5.060620 |
On 11/12/06 12:10, "Tian, Kevin" <kevin.tian@xxxxxxxxx> wrote: > Yes, there's no interrupt from it. But what's the known frequency? > CALIBRATE_LATCH or CLOCK_TICK_RATE? platform_timer_scale > is set to the later, and so ch2 needs to work on same frequency or > else count value will result incorrect offset. However I didn't see such > setting on ch2. Does I miss something? :-) All the PIT channels tick at CLOCK_TICK_RATE. Mode-0 is not auto-relatching, so when the counter reaches 0000 it carries on FFFF, FFFE, FFFD, .... So we calculate platform system time as: system_timestamp + (pit_timestamp - pit_timenow) * (delta_system/delta_pit) -- Keir _______________________________________________ Xen-devel mailing list Xen-devel@xxxxxxxxxxxxxxxxxxx http://lists.xensource.com/xen-devel
| <Prev in Thread] | Current Thread | [Next in Thread> |
|---|---|---|
| ||
| Previous by Date: | [Xen-devel] Testing status of HVM (Intel VT) on 64bit XEN unstable c/s 12895 , Ed Smith |
|---|---|
| Next by Date: | Re: [Xen-devel] xm dump-core and analyzing , David Pilger |
| Previous by Thread: | [Xen-devel] RE: A question about PIT platform timer , Tian, Kevin |
| Next by Thread: | Re: [Xen-devel] RE: A question about PIT platform timer , Keir Fraser |
| Indexes: | [Date] [Thread] [Top] [All Lists] |