On Thu, Jun 13, 2013 at 7:09 PM, Jiang Liu (Gerry) <jiang.liu@xxxxxxxxxx> wrote: > On 2013/6/14 2:42, Yinghai Lu wrote: >> >> On Thu, Jun 13, 2013 at 9:32 AM, Jiang Liu <jiang.liu@xxxxxxxxxx> wrote: >>> >>> Alexander E. Patrakov <patrakov@xxxxxxxxx> reports two bugs related to >>> dock station support on Sony VAIO VPCZ23A4R. Actually there are at least >>> four bugs related to Sony VAIO VPCZ23A4R dock support. >>> 1) can't correctly detect hotplug slot for dock state >>> 2) resource leak on undocking >>> 3) resource allocation failure for dock devices >>> 4) one bug in intel_snd_hda driver >>> >>> The first patch fixes issue 1, and the second patch fixes issue 2. >>> These two patches, if accepted, should be material for stable branches >>> too. >>> Patch 3-9 are code improvement for ACPI and dock driver. >>> >>> I have found the root cause for issue three, but still working on >>> solutions, and seems can't be solve in short time. So please help >>> to review and test patches for issue 1) and 2) first. >> >> >> the 3) is about pci resource allocation? >> because pcibios_add_bus is called too early? >> >> If that is case, we should have something like attached patch for it. >> >> With that, we will not need to worry about _OSC set for 3.10 etc. >> > Hi Yinghai, > Seems not related to pcibios_add_bus(). According to my > investigation, the issue is caused by difference in PCI resource > assignment between boot time and runtime hotplug. On x86 platforms, > it respects PCI resource assignment from BIOS and only reassign > resources for unassigned BARs. But with acpiphp, it ignores BIOS > resource assignment and reassign all resources by OS. > If we have enough resources, reassigning all PCI resources should > work too, but may fail if we are under resource constraints. On the > other handle, current PCI IOMM align algorithm may waste huge MMIO > address space if we have some PCI devices with huge IOMM BAR. > On this Sony laptop, BIOS allocates limited IOMM resources for > the dock station and the dock station has a gfx which has a 256MB > IOMM BAR. So current acpiphp driver fails to allocate resources > for most devices on the dock station. Is it a regression? > Currently I'm trying to change acpiphp to respect BIOS resource > assignment by calling pcibios_survey_resource_bus(), as in pci_root.c. > The other way is to change the IOMM resource allocation algorithm, > but obviously it's much more risky of regressions if changing the > algorithm. that is not going to help, need to increase bridge resource. please check if BIOS have setup option about hotplug MMIO pad size. Yinghai -- 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
