From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [Qemu-devel] [PATCH 3/4] Add support for HPET periodic timer. Date: Wed, 22 Aug 2007 10:03:32 +0300 Message-ID: <46CBDFC4.5060207@qumranet.com> References: <20070817231149.544849769@gmail.com> <20070817231406.493008599@gmail.com> <1187724245.2562.28.camel@fuego> <68676e00708211240k7237bf21k131257dd28063d26@mail.gmail.com> <1187727322.2562.41.camel@fuego> <20070822064851.GA16295@danken-desk.qumranet.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: kvm-devel-TtF/mJH4Jtrk1uMJSBkQmQ@public.gmane.org, qemu-devel-qX2TKyscuCcdnm+yROfE0A@public.gmane.org To: Dan Kenigsberg Return-path: In-Reply-To: <20070822064851.GA16295-RO/WWmT55CHJJbofclyLPCHBx9XpghdU@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: kvm-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Errors-To: kvm-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Id: kvm.vger.kernel.org Dan Kenigsberg wrote: > On Tue, Aug 21, 2007 at 01:15:22PM -0700, Matthew Kent wrote: > >> On Tue, 2007-21-08 at 21:40 +0200, Luca wrote: >> >>> On 8/21/07, Matthew Kent wrote: >>> >>>> On Sat, 2007-18-08 at 01:11 +0200, Luca Tettamanti wrote: >>>> >>>>> plain text document attachment (clock-hpet) >>>>> Linux operates the HPET timer in legacy replacement mode, which means that >>>>> the periodic interrupt of the CMOS RTC is not delivered (qemu won't be able >>>>> to use /dev/rtc). Add support for HPET (/dev/hpet) as a replacement for the >>>>> RTC; the periodic interrupt is delivered via SIGIO and is handled in the >>>>> same way as the RTC timer. >>>>> >>>>> Signed-off-by: Luca Tettamanti >>>>> >>>> I must be missing something silly here.. should I be able to open more >>>> than one instance of qemu with -clock hpet? Because upon invoking a >>>> second instance of qemu HPET_IE_ON fails. >>>> >>> It depends on your hardware. Theoretically it's possible, but I've yet >>> to see a motherboard with more than one periodic timer. >>> >> Ah thank you, after re-reading the docs I think I better understand >> this. >> > > In a risk of being off-topic, maybe you can help me try the hpet support. > When I try the hpet Documentation demo I get > > # ./hpet poll /dev/hpet 1 1000 > -hpet: executing poll > hpet_poll: info.hi_flags 0x0 > hpet_poll, HPET_IE_ON failed > > while I have > > $ dmesg|grep -i HPET > ACPI: HPET 7D5B6AE0, 0038 (r1 A M I OEMHPET 5000708 MSFT 97) > ACPI: HPET id: 0x8086a301 base: 0xfed00000 > hpet0: at MMIO 0xfed00000, IRQs 2, 8, 0, 0 > hpet0: 4 64-bit timers, 14318180 Hz > hpet_resources: 0xfed00000 is busy > Time: hpet clocksource has been installed. > > Any idea what I am misconfiguring? > Maybe the kernel is using the timer, so userspace can't. Just a guess. -- Do not meddle in the internals of kernels, for they are subtle and quick to panic. ------------------------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Still grepping through log files to find problems? Stop. Now Search log events and configuration files using AJAX and a browser. Download your FREE copy of Splunk now >> http://get.splunk.com/