Re: [Qemu-devel] [PATCH 0/2] Add get_dev_path callback to ISA bus.

[Markus Armbruster <armbru@redhat.com>]

Gleb Natapov <gleb@redhat.com> writes:

> On Mon, Oct 25, 2010 at 07:53:41PM +0200, Markus Armbruster wrote:
>> Gleb Natapov <gleb@redhat.com> writes:
>> 
>> > On Mon, Oct 25, 2010 at 05:10:15PM +0200, Markus Armbruster wrote:
>> >> Gleb Natapov <gleb@redhat.com> writes:
>> >> 
>> >> > PCI bus already has one. For ISA bus this patch series uses device's
>> >> > ioports to uniquely describe it. For isa-ide, for example, get_dev_path
>> >> > method returns:
>> >> > 01f0-01f7,03f6 for first IDE controller
>> >> > 0170-0177,0376 for second one
>> >> 
>> >> Any I/O port used by the device identifies it.  I'd say a common
>> >> identifier is the "I/O base", the lowest I/O port used.
>> > So use only first port from the string. More information is better then
>> > less information. You can always drop information you do not need.
>> 
>> I'd prefer canonical bus addresses to be terse.  It's not the place to
>> give additional information.
>
> I'd prefer them to give full info but not more. I don't see why you
> point is more valid then mine.

Full information about ISA resources is more than I/O ports, it also
includes IRQs and DMA channels.

An address is not the place to give full information.  The purpose of an
address is to name a thing, not to give full information about that
thing.


By the way, get_dev_path() really needs a written contract.  Actually,
all the qdev and qbus callbacks do.