Messages in this thread | | | Date | Thu, 23 Feb 2006 14:58:51 +0900 | From | Kenji Kaneshige <> | Subject | Re: [PATCH 0/6] PCI legacy I/O port free driver (take2) |
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Benjamin Herrenschmidt wrote: >>Here, there are many PCI devices that provide both I/O port and MMIO >>interface, and some of those devices can be handled without using I/O >>port interface. The reason why such devices provide I/O port interface >>is for compatibility to legacy OSs. So this kind of devices should >>work even if enough I/O port resources are not assigned. The "PCI >>Local Bus Specification Revision 3.0" also mentions about this topic >>(Please see p.44, "IMPLEMENTATION NOTE"). On the current linux, >>unfortunately, this kind of devices don't work if I/O port resources >>are not assigned, because pci_enable_device() for those devices fails. > > > Which is where the real problem is ... I'm afraid you are doing a > workaround for the wrong issue... do we really need to assign all > resources to the device at pci_enable_device() time ? Yeah, I know, that > sounds gross... but think about it... doesn't pci_request_region(s) look > like a better spot ? Or maybe we should change pci_enable_device() > itself to take a mask of BARs that are relevant. That would help dealing > with a couple of other cases of devices where some BARs really need to > be ignored... > > The later is probably the best approach without breaking everything, by > having a new pci_enable_resources(mask) that would take a mask of BARs > to enable, with pci_enable_device() becoming just a call to the former > for all BARs .... > > Ben. >
I guess the existing pci_enable_device_bars() is very similar to your pci_enable_resources(). We already discussed it at:
http://marc.theaimsgroup.com/?l=linux-kernel&m=114000705026791&w=2
Thanks, Kenji Kaneshige - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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