On Tue, Mar 12, 2013 at 4:20 PM, Bjorn Helgaas <bhelgaas@xxxxxxxxxx> wrote: > On Sat, Mar 9, 2013 at 2:20 AM, Chris Clayton <chris2553@xxxxxxxxxxxxxx> wrote: >> On 03/08/13 22:57, Bjorn Helgaas wrote: >>> Thanks. I opened this bug report: >>> https://bugzilla.kernel.org/show_bug.cgi?id=54981 to keep track of >>> your logs. Hi Chris, The current Linux acpiphp driver doesn't do anything unless it finds devices with _EJ0 or _RMV methods, and your DSDT has neither. But I think that implementation is incorrect because I'm not convinced that those methods are required in order to do hotplug via ACPI. For example, your DSDT *does* have an _L01 method that does notifications to the root ports. I suspect that hotplug events on your box generate an SCI that invokes that method. Linux basically ignores the resulting notify events, and I suspect that hotplug works on Windows because it is paying attention to them. Can you build a kernel with CONFIG_ACPI_DEBUG=y, do the following, and attach all the output to the bugzilla? 1) Boot with empty ExpressCard slot (without using "pcie_ports=native") 2) # echo 0x00010004 > /sys/module/acpi/parameters/debug_layer 3) # echo 0x08000004 > /sys/module/acpi/parameters/debug_level 4) # lspci -vv 5) # setpci -s 1c.3 0x42.w 6) # setpci -s 1c.3 0x5a.w 7) # setpci -s 1c.3 0xd8.l 8) Insert ExpressCard 9) # setpci -s 1c.3 0x5a.w 10) # dmesg Here's what I think we'll see: - Slot Implemented (bit 8 of XCAP at 0x42) set, indicating a slot is implemented below this root port - Hot Plug SCI Enable (bit 30 of MPC at 0xd8) set, indicating that the root port should generate an SCI whenever a hotplug event is detected - Presence Detect State (bit 6 of SLTSTS at 0x5a) change from 0 with the slot empty to 1 with the slot occupied - pciehp doing nothing (since _OSC didn't grant the OS permission to use PCIe native hotplug) - dmesg indication of the SCI, leading to a Bus Check notification to \_SB.PCI0.RP04, which is the 1c.3 root port leading to the ExpressCard slot A Bus Check notification means we're supposed to re-enumerate starting at that device. If we *did* re-enumerate, we would find the new ExpressCard. Thanks, Bjorn -- 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
