Re: [kvm-devel] [Qemu-devel] [PATCH 3/4] Add support for HPET periodic timer.

2007-08-25 Thread Dan Kenigsberg
On Fri, Aug 24, 2007 at 10:18:47PM +0200, Luca wrote:
 On 8/23/07, Dan Kenigsberg [EMAIL PROTECTED] wrote:
  On Thu, Aug 23, 2007 at 12:09:47AM +0200, Andi Kleen wrote:
$ dmesg |grep -i hpet
ACPI: HPET 7D5B6AE0, 0038 (r1 A M I  OEMHPET   5000708 MSFT   97)
ACPI: HPET id: 0x8086a301 base: 0xfed0
hpet0: at MMIO 0xfed0, IRQs 2, 8, 0, 0
hpet0: 4 64-bit timers, 14318180 Hz
hpet_resources: 0xfed0 is busy
  
   What kernel version was that? There was a bug that caused this pre .22
  
 
  I have vanilla 2.6.22.3 on that machine.
 
 Try:
 cat /sys/devices/system/clocksource/clocksource0/available_clocksource
 
 do you see HPET listed twice?
 
No, only once. Is that wrong?

# cat /sys/devices/system/clocksource/clocksource0/available_clocksource
hpet acpi_pm jiffies tsc 

# cat /sys/devices/system/clocksource/clocksource0/current_clocksource 
tsc 

Dan.




Re: [kvm-devel] [Qemu-devel] [PATCH 3/4] Add support for HPET periodic timer.

2007-08-24 Thread Luca
On 8/23/07, Dan Kenigsberg [EMAIL PROTECTED] wrote:
 On Thu, Aug 23, 2007 at 12:09:47AM +0200, Andi Kleen wrote:
   $ dmesg |grep -i hpet
   ACPI: HPET 7D5B6AE0, 0038 (r1 A M I  OEMHPET   5000708 MSFT   97)
   ACPI: HPET id: 0x8086a301 base: 0xfed0
   hpet0: at MMIO 0xfed0, IRQs 2, 8, 0, 0
   hpet0: 4 64-bit timers, 14318180 Hz
   hpet_resources: 0xfed0 is busy
 
  What kernel version was that? There was a bug that caused this pre .22
 

 I have vanilla 2.6.22.3 on that machine.

Try:
cat /sys/devices/system/clocksource/clocksource0/available_clocksource

do you see HPET listed twice?

Luca




Re: [kvm-devel] [Qemu-devel] [PATCH 3/4] Add support for HPET periodic timer.

2007-08-22 Thread Dan Kenigsberg
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 [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.

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: 0xfed0
hpet0: at MMIO 0xfed0, IRQs 2, 8, 0, 0
hpet0: 4 64-bit timers, 14318180 Hz
hpet_resources: 0xfed0 is busy
Time: hpet clocksource has been installed.

Any idea what I am misconfiguring?

Thanks,

Dan.




Re: [kvm-devel] [Qemu-devel] [PATCH 3/4] Add support for HPET periodic timer.

2007-08-22 Thread Avi Kivity
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 [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.
 

 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: 0xfed0
 hpet0: at MMIO 0xfed0, IRQs 2, 8, 0, 0
 hpet0: 4 64-bit timers, 14318180 Hz
 hpet_resources: 0xfed0 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.





Re: [kvm-devel] [Qemu-devel] [PATCH 3/4] Add support for HPET periodic timer.

2007-08-22 Thread Andi Kleen
On Wed, Aug 22, 2007 at 10:03:32AM +0300, Avi Kivity wrote:
 Maybe the kernel is using the timer, so userspace can't.  Just a guess.

HPET has multiple timers (variable, but typically 2 or 4). The kernel
only uses timer 0. It's possible someone else in user space is using
it though. Try lsof /dev/hpet

-Andi




Re: [kvm-devel] [Qemu-devel] [PATCH 3/4] Add support for HPET periodic timer.

2007-08-22 Thread Dan Kenigsberg
On Wed, Aug 22, 2007 at 02:34:24PM +0200, Andi Kleen wrote:
 On Wed, Aug 22, 2007 at 10:03:32AM +0300, Avi Kivity wrote:
  Maybe the kernel is using the timer, so userspace can't.  Just a guess.
 
 HPET has multiple timers (variable, but typically 2 or 4). The kernel
 only uses timer 0. It's possible someone else in user space is using
 it though. Try lsof /dev/hpet

Thanks for the ideas; however even after I made the kernel use tsc as
time source, and made sure that no one opens /dev/hpet, I fail to use
HPET (with same errors as before)

I now have

$ dmesg |grep -i hpet
ACPI: HPET 7D5B6AE0, 0038 (r1 A M I  OEMHPET   5000708 MSFT   97)
ACPI: HPET id: 0x8086a301 base: 0xfed0
hpet0: at MMIO 0xfed0, IRQs 2, 8, 0, 0
hpet0: 4 64-bit timers, 14318180 Hz
hpet_resources: 0xfed0 is busy

Any other idea?

Dan.




Re: [kvm-devel] [Qemu-devel] [PATCH 3/4] Add support for HPET periodic timer.

2007-08-22 Thread Andi Kleen
 $ dmesg |grep -i hpet
 ACPI: HPET 7D5B6AE0, 0038 (r1 A M I  OEMHPET   5000708 MSFT   97)
 ACPI: HPET id: 0x8086a301 base: 0xfed0
 hpet0: at MMIO 0xfed0, IRQs 2, 8, 0, 0
 hpet0: 4 64-bit timers, 14318180 Hz
 hpet_resources: 0xfed0 is busy

What kernel version was that? There was a bug that caused this pre .22

-Andi