misc questions about the device&driver arch
avalonwallace at gmail.com
Sun May 21 01:08:03 PDT 2006
On 5/21/06, Warner Losh <imp at bsdimp.com> wrote:
> nope. It may be called once per bus instance per driver, if the bus
> is not self-identifying. If the bus is self-idntiying, chances are
> that it will not be called. pci never calls its children drivers'
> identify routine because it already knows all the children on the bus
> and doesn't need the leaf drivers to go find instances of themselves.
> the isa bus driver, on the other hand, does call the identify routine
> so that pre-plug and play standard device enumeration can happen.
the defination of self-enumerating
what does self-enumerating mean ?
does that mean the pci way of looping through configuration space ?
does that happen in start time and hotplug time ?
pci doesn't need the leaf drivers to go find instances of themselves.
does that mean that self-enumerating device system use the top down way ,
and the non- self-enumerating device system use the down -top way
i guest pci hot plug need some magic to identify or emulae(loop pci sons )
There r so many hot plug specifications ,SHPC hotplug ,PCIE hotplug
and compaq hotplug and so on , in linux ,they use different driver for
so i think for us to implement in freeBSD ,just do 1 by 1:)
we who r about to die,salute u!
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