> -----Original Message----- > From: Paolo Bonzini [mailto:paolo.bonz...@gmail.com] On Behalf Of Paolo > Bonzini > Sent: Friday, March 02, 2012 8:14 PM > To: Zhang, Yang Z > Cc: qemu-devel@nongnu.org; Jan Kiszka; k...@vger.kernel.org; > aligu...@us.ibm.com; Marcelo Tosatti > Subject: Re: [PATCH v3 5/7] RTC:Add RTC update-ended interrupt support > > Il 02/03/2012 08:00, Zhang, Yang Z ha scritto: > > Use a timer to emulate update cycle. When update cycle ended and UIE > > is setting, then raise an interrupt. The timer runs only when UF or AF is > > cleared. > > Isn't AF=0 the common case when the RTC starts, so the timer always runs until > the time crosses midnight?
Right. But for server platform, the guest will run always. One day is not a big cost. And if guest not use the alarm. Then the timer will never run again. Also, I can set the default value in alarm to 'don't care' mode. And this will avoid the timer always runs. best regards yang