svn commit: r223519 - head/etc/devd

[Warner Losh]

On Jun 28, 2011, at 2:45 AM, Alexey Dokuchaev wrote:

> On Sun, Jun 26, 2011 at 10:14:13PM -0600, Warner Losh wrote:
>> Not in GENERIC.  9.0 is getting ready to feature freeze any minute, so
>> there's no time to do the testing that a radical change like that would
>> require.
> 
> Fair enough.  Right now, this work seems to cover only USB kernel modules,
> is it so?  Is expansion into generic PCI area also planned, provided that
> you've already had some ideas and seem to be willing to pick up the work
> given enough support from the other developers (please excuse me if my
> understanding is wrong)?

The reason we were able to relatively quickly generate this file from USB is because USB is very regular and uniform in its probe routines.  They all have (or could be converted to have) something approximating the same format.

PCI isn't even remotely close to this, and the techniques that worked for USB (and some of the short cuts taken) can't work for PCI for us.  There's no uniformity in the PCI space, although many of the PCI drivers use a similar design pattern.  They would all have to be converted to using the same thing, which is kinda impractical at the moment (since many have additional, driver specific fields).  While the tool is kinda flexible enough to cope with this situation, more and more code winds up in the tool to cope than is appropriate for the tool.

That's why this feature is experimental.  For what it works for, it works great.  For everything else, it is a lot of work to make it happy on a wide-spread enough scale.  It is very instructive for how to approach things, but embeds too much knowledge of the bus code into the tool to generate these files than is appropriate (since it is duplicated information from the driver, not exported from the bus/driver).

Warner