On Tue, Oct 17, 2017 at 4:39 PM, Brian Norris <briannorris@xxxxxxxxxxxx> wrote: > On Fri, Oct 13, 2017 at 11:51:52AM -0500, Bjorn Helgaas wrote: > > If so, I really don't want to get involved in that, because that's an > > issue that needs to be resolved by the vendors and the PCI-SIG. If we > > Judging by conversations with these vendors, I can't really imagine them > proactively dealing with the PCI-SIG on this. Is that really what you > think will work best? > > I personally believe deferring (i.e., ignoring) the problem will not > cause any change; badly behaved vendors will just do whatever suits > them, and system designers will have to figure it out somehow -- ACPI > systems will have platform-specific behavior hidden in firmware; device > tree systems will do whatever they want out of tree; and the rare device > tree system that gets upstream support will either have suboptimal power > management, or have to have these sorts of conversations again. None of > that puts pressure on an endpoint vendor to talk to the PCI-SIG. I'll add a little more to my claim about ACPI systems. I chatted a little more with another engineer on my team who has dealt with ACPI firmware for a few generations of Intel platforms. Even among the latest two platforms he dealt with, there have been two different sorts of chipset bugs (at the host/root complex side, not just the endpoint) that have yielded different decisions on how to handle PERST#. This was opaque to Linux though, since that's how system firmware rolls :) I expect this will not be the last discrepancy on how to handle PERST#. And to my knowledge, none of the above initiated any discussion with the PCI-SIG. Brian -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
