Re: [Qemu-devel] [PATCH 3/4] Add support for HPET periodic timer.
Hello, Can you confirm to me that if I have only one periodic timer on my motherboard I can only have one qemu-instance running using hpet? Thanks. François. Le mardi 21 août 2007 à 21:40 +0200, Luca a écrit : On 8/21/07, Matthew Kent [EMAIL PROTECTED] 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 [EMAIL PROTECTED] 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. dmesg | grep hpet should tell you something like: hpet0: 3 64-bit timers, 14318180 Hz Luca
Re: [Qemu-devel] [PATCH 3/4] Add support for HPET periodic timer.
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 [EMAIL PROTECTED] 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. I also tried running the example in the kernel docs under Documentation/hpet.txt [EMAIL PROTECTED] [/home/mkent]# ./demo poll /dev/hpet 1 1000 -hpet: executing poll hpet_poll: info.hi_flags 0x0 hpet_poll: expired time = 0x8 hpet_poll: revents = 0x1 hpet_poll: data 0x1 in another term [EMAIL PROTECTED] [/home/mkent]# ./demo poll /dev/hpet 1 1000 -hpet: executing poll hpet_poll: info.hi_flags 0x0 hpet_poll, HPET_IE_ON failed This is on 2.6.23-rc3 x86_64 with the patch-2.6.23-rc3-hrt2.patch hrtimers patch. -- Matthew Kent [EMAIL PROTECTED] http://magoazul.com
Re: [Qemu-devel] [PATCH 3/4] Add support for HPET periodic timer.
On 8/21/07, Matthew Kent [EMAIL PROTECTED] 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 [EMAIL PROTECTED] 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. dmesg | grep hpet should tell you something like: hpet0: 3 64-bit timers, 14318180 Hz Luca
Re: [Qemu-devel] [PATCH 3/4] Add support for HPET periodic timer.
On Tue, 2007-21-08 at 21:40 +0200, Luca wrote: On 8/21/07, Matthew Kent [EMAIL PROTECTED] 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 [EMAIL PROTECTED] 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. -- Matthew Kent [EMAIL PROTECTED] http://magoazul.com
