On Monday, July 28, 2008 1:44 am Kenji Kaneshige wrote: > Jesse Barnes wrote: > > I think that's fine (automatically creating duplicate devices with names > > to differentiate them), but I think we should also try harder to avoid > > adding duplicates. > > > > In Pierre's case, and on my T61, there's only one actual hotplug slot > > available, but the firmware creates duplicate physical slot numbers and > > sets the HP_CAP bit on everything, both of which are obviously wrong > > (well I suppose you could pop these chips off the board, but it's not > > very practical). However, afaict that "other" OS uses the _RMV method to > > determine whether a given slot is actually hot pluggable. On my T61 at > > least, this seems to be accurate: only one of my EXP* objects has a _RMV > > method. > > > > So maybe the PCIe hotplug driver should be checking for that method when > > ACPI is available? We already try to use _OSC etc., so checking for _RMV > > first would make sense... > > As you pointed out, the root cause might not a problem of slot naming, > but a problem of slots detection, because pciehp driver detects multiple > PCIe hotplug slots even thought your and Pierre's system seems to have > only one hotplug slot. So I think we should also consider the problem > from this view point (slot detection). > > But, I think simply checking for _RMV method first is dangerous because > I think there are many systems that doesn't implement _RMV for PCIe > hotplug slots (at least, my system doesn't implement that. Anyway, > I would like to look at the documents/specifications that mention _RMV > method for determining whether a given slot is hot pluggable. Do you > have any information about that? I think PCI Local Bus, PCI Express and > PCI Firmware specification don't mention that. I think hot pluggable slots > on your, Pierre's and Matthew's system are ExpressCard slots. So I guess > ExpressCard specification might define something about this. But > unfortunately, I don't have ExpressCard specification. Can anyone access > ExpressCard spec? Your systems don't have _RMV methods for the hotpluggable PCIe slots in the DSDT? That's a shame; the Windows docs I found on PCIe hotplug seemed to indicate that _RMV and _OSC (under Vista) were used to detect whether a given slot was hot pluggable (I just googled for "windows pcie hotplug" or something) so I was hoping that would be a reliable method... Any other ideas? I'll go see if I can dig up some ExpressCard info. Thanks, Jesse -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
