> -----Original Message----- > From: linux-pci-owner@xxxxxxxxxxxxxxx > [mailto:linux-pci-owner@xxxxxxxxxxxxxxx] On Behalf Of Shlomo Pongratz > Sent: Sunday, July 29, 2012 9:36 PM > To: Greg KH > Cc: linux-pci@xxxxxxxxxxxxxxx; linux-hotplug@xxxxxxxxxxxxxxx > Subject: Re: Cabled PCIE device hotplug/hot-removal > > On Thu, Jul 26, 2012 at 8:09 PM, Greg KH <greg@xxxxxxxxx> wrote: > > On Thu, Jul 26, 2012 at 08:03:09PM +0300, Shlomo Pongratz wrote: > >> Hi, > >> > >> I have a PCIe device connected with cables to a host (kernel 3.5.0-rc7+). > >> What are the handler I need to add to a driver in order to catch cable > >> pull-out / push-in? > > > > You shouldn't need anything special, aren't you already getting probe > > and disconnect callbacks when the device is discovered and removed? > Note that if the controller doesn't support "surprise removal", pciehp does nothing (just print a message) when plugging/unplugging the device. You need to power on the slot by "echo 1 > /sys/bus/pci/slots/XXX/power" after plugging the device. By this, pciehp will power on the slot and driver's .prove callback will be called. And for removal, you need to "echo 0 > /sys/bus/pci/slots/XXX/power" before unplugging the device. By doing this, driver's .remove callback will be called and then pciehp will power down the slot. If the controller supports "surprise removal" driver's .probe/.remove callbacks are called automatically by the pciehp's event handler when plugging/unplugging event (presence change detect event) happens. > When the device is loaded the probe is called > When I "echo 1" to the remove sysfs entry the remove callback is called. > But when I power down the card no callback is called. You need to "echo 0 > /sys/bus/pci/slots/XXX/power" to remove the device if you are using pciehp. > > > >> The pcisig presentation > >> > "http://www.pcisig.com/developers/main/training_materials/get_document > ?doc_id=f4ca40ec1721aa7fadd05e2903b0172c36656294" > >> talks about PERST# detection for cabled PCIe hotplug. > >> > >> Does the kernel detect it? > >> > >> None of the pci_driver or pci_error_handlers callbacks were called > >> when using powered down/up the device (electrically). How did you power down/up the device (electrically)? > > > > Do you have the pciehp driver loaded properly when this happens? > > My {dot}config includes it into the kernel, i.e. > CONFIG_HOTPLUG_PCI_PCIE=y > You can see what kind of hot-plug driver manages the slot by checking /sys/bus/pci/slots/XXX/module symbolic link. On my system which has some PCIe hot-plug slots, I can see the following $ ls /sys/bus/pci/slots/* -l /sys/bus/pci/slots/21: total 0 -r--r--r--. 1 root root 4096 Aug 1 02:55 adapter -r--r--r--. 1 root root 4096 Aug 1 02:55 address -rw-r--r--. 1 root root 4096 Aug 1 02:55 attention -r--r--r--. 1 root root 4096 Aug 1 02:55 cur_bus_speed -r--r--r--. 1 root root 4096 Aug 1 02:55 latch -r--r--r--. 1 root root 4096 Aug 1 02:55 max_bus_speed lrwxrwxrwx. 1 root root 0 Aug 1 02:55 module -> ../../../../module/pciehp -rw-r--r--. 1 root root 4096 Aug 1 02:55 power /sys/bus/pci/slots/22: <snip.> And pciehp_debug option might help you. With this option, you can get the controller infomation like below. pciehp 0000:0d:00.0:pcie24: Hotplug Controller: pciehp 0000:0d:00.0:pcie24: Seg/Bus/Dev/Func/IRQ : 0000:0d:00.0 IRQ 51 pciehp 0000:0d:00.0:pcie24: Vendor ID : 0x111d pciehp 0000:0d:00.0:pcie24: Device ID : 0x807f pciehp 0000:0d:00.0:pcie24: Subsystem ID : 0x159c pciehp 0000:0d:00.0:pcie24: Subsystem Vendor ID : 0x10cf pciehp 0000:0d:00.0:pcie24: PCIe Cap offset : 0x40 pciehp 0000:0d:00.0:pcie24: PCI resource [14] : [mem 0x92a00000-0x92bfffff] pciehp 0000:0d:00.0:pcie24: PCI resource [15] : [mem 0x92000000-0x921fffff 64bit pref] pciehp 0000:0d:00.0:pcie24: Slot Capabilities : 0x00a8005e pciehp 0000:0d:00.0:pcie24: Physical Slot Number : 21 pciehp 0000:0d:00.0:pcie24: Attention Button : no pciehp 0000:0d:00.0:pcie24: Power Controller : yes pciehp 0000:0d:00.0:pcie24: MRL Sensor : yes pciehp 0000:0d:00.0:pcie24: Attention Indicator : yes pciehp 0000:0d:00.0:pcie24: Power Indicator : yes pciehp 0000:0d:00.0:pcie24: Hot-Plug Surprise : no pciehp 0000:0d:00.0:pcie24: EMI Present : no pciehp 0000:0d:00.0:pcie24: Command Completed : yes pciehp 0000:0d:00.0:pcie24: Slot Status : 0x0000 pciehp 0000:0d:00.0:pcie24: Slot Control : 0x07c0 pciehp 0000:0d:00.0:pcie24: Link Active Reporting supported Regards, Kenji Kaneshige -- To unsubscribe from this list: send the line "unsubscribe linux-hotplug" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
