PCI Error Recovery API Proposal. (WAS:: [PATCH/RFC] PCI ErrorRecovery)

[Paul Mackerras]

Nguyen, Tom L writes:

> How does an io_check_error() support PCI Express comprehensive error
> information?

It doesn't.  The io_check_error() would be a generic, cross-platform
thing.  You would have some PCI-Express-specific interfaces to get
PCI-Express-specific error information.

You are facing a similar tension to what we are facing - the tension
between wanting drivers to be able to use all the facilities of the
platform, but not wanting to make the driver so platform-specific that
it is useless on any other platform (and you end up maintaining all
the drivers for the platform).

The ideal thing is to find a way to express the facilities of the
different platforms we have in a sufficiently abstract or generic way
that drivers can use a common error detection and recovery strategy
across multiple platforms.  That is what we are trying to do, and if
we can succeed at that we will reduce the development and maintenance
effort for everyone.

That means, however, that the driver will not be dealing with the
specific nitty-gritty platform-specific details of exactly what went
wrong and where.  If the driver really has to deal with those details
then it becomes platform-specific.  That may be acceptable for a few
drivers for which the extra effort (including the ongoing maintenance
effort) can be justified, but it is not practicable to maintain
platform-specific versions of every driver.

Paul.