pcie_init() invokes pcie_disable_notification() for empty slots, which in turn disables the Command Complete interrupt (unset PCI_EXP_SLTCTL_CCIE) and right after that waits for Command Complete event (PCI_EXP_SLTSTA_CC). This results in longer boot time - 4 seconds of delay for each empty slot: [ 4.200325] pciehp 0042:04:08.0:pcie204: Slot #40 AttnBtn+ PwrCtrl+ MRL- AttnInd+ PwrInd+ HotPlug+ Surprise- Interlock- NoCompl- LLActRep+ [ 4.200607] pciehp 0042:04:08.0:pcie204: pciehp_get_power_status: SLOTCTRL 80 value read 1c0 [ 6.217938] pciehp 0042:04:08.0:pcie204: Timeout on hotplug command 0x01c0 (issued 2020 msec ago) [ 6.217966] pciehp 0042:04:08.0:pcie204: pcie_disable_notification: SLOTCTRL 80 write cmd 0 [ 6.237938] pciehp 0042:04:08.0:pcie204: Timeout on hotplug command 0x01c0 (issued 2040 msec ago) [ 8.257939] pciehp 0042:04:08.0:pcie204: Timeout on hotplug command 0x05c0 (issued 2020 msec ago) [ 8.257974] pciehp 0042:04:08.0:pcie204: pciehp_power_off_slot: SLOTCTRL 80 write cmd 400 [ 8.258034] pci_bus 0042:07: dev 00, created physical slot 40 [ 8.277941] pciehp 0042:04:08.0:pcie204: Timeout on hotplug command 0x05c0 (issued 2040 msec ago) [ 8.277967] pciehp 0042:04:08.0:pcie204: pcie_enable_notification: SLOTCTRL 80 write cmd 1031 Signed-off-by: Sergey Miroshnichenko <s.miroshnichenko@xxxxxxxxx> Cc: Lukas Wunner <lukas@xxxxxxxxx> --- drivers/pci/hotplug/pciehp_hpc.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/pci/hotplug/pciehp_hpc.c b/drivers/pci/hotplug/pciehp_hpc.c index 6a2365cd794e..eec5d6107360 100644 --- a/drivers/pci/hotplug/pciehp_hpc.c +++ b/drivers/pci/hotplug/pciehp_hpc.c @@ -118,8 +118,10 @@ static void pcie_wait_cmd(struct controller *ctrl) if (ctrl->slot_ctrl & PCI_EXP_SLTCTL_HPIE && ctrl->slot_ctrl & PCI_EXP_SLTCTL_CCIE) rc = wait_event_timeout(ctrl->queue, !ctrl->cmd_busy, timeout); - else + else if (ctrl->slot_ctrl & PCI_EXP_SLTCTL_CCIE) rc = pcie_poll_cmd(ctrl, jiffies_to_msecs(timeout)); + else + return; if (!rc) ctrl_info(ctrl, "Timeout on hotplug command %#06x (issued %u msec ago)\n", -- 2.20.1
