Tarl Neustaedter wrote:
On 2010-1-5 3:53 PM, Igor Kovalenko wrote:
[...] On the firmware side, interesting thing is you cannot disarm alarm. What if instance is then closed?
That's bad. "xt 0 alarm" should disarm the alarm - and close should too. Why doesn't it?
In the case of console, you won't have a problem under normal operation, but other devices which use alarms might indeed cause problems.
You'll have a problem with the console if you use the "input", "output" or "io" methods to switch the input or output console devices.
I'm assuming that Igor is referring to the Qemu timer model here, since the OpenBIOS alarm word is currently defined as "2 drop" ;)
In terms of the console, OpenBIOS currently doesn't use alarm interrupts there either - it just sits in a busy-wait loop checking an I/O port or similar to determine when a new character is incoming.
ATB,
Mark.