Hello Bjorn, Was wanting to check your interest on up streaming this one. This one is fairly self-contained and simple, and allows to use polling on a per-port basis. Please let me know you have any comments. Thanks, Rajat > -----Original Message----- > From: Rajat Jain [mailto:rajatxjain@xxxxxxxxx] > Sent: Monday, March 31, 2014 4:52 PM > To: Bjorn Helgaas; linux-pci@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx > Cc: Rajat Jain; Guenter Roeck > Subject: [PATCH] pci/pciehp: Allow polling/irq mode to be decided on a per- > port basis > > Today, there is a global pciehp_poll_mode module parameter using which > either _all_ the hot-pluggable ports are to use polling, or _all_ the ports are > to use interrupts. > > In a system where a certain port has IRQ issues, today the only option is to > use the parameter that converts ALL the ports to use polling mode. > This is not good, and hence this patch intruduces a bit field that can be set > using a PCI quirk that indicates that polling should always be used for this > particular PCIe port. The remaining ports can still hoose to continue to > operate in whatever mode they wish to. > > Signed-off-by: Rajat Jain <rajatxjain@xxxxxxxxx> > Signed-off-by: Rajat Jain <rajatjain@xxxxxxxxxxx> > Signed-off-by: Guenter Roeck <groeck@xxxxxxxxxxx> > --- > drivers/pci/hotplug/pciehp.h | 1 + > drivers/pci/hotplug/pciehp_hpc.c | 16 ++++++++++------ > include/linux/pci.h | 1 + > 3 files changed, 12 insertions(+), 6 deletions(-) > > diff --git a/drivers/pci/hotplug/pciehp.h b/drivers/pci/hotplug/pciehp.h > index d208791..753a3b4 100644 > --- a/drivers/pci/hotplug/pciehp.h > +++ b/drivers/pci/hotplug/pciehp.h > @@ -98,6 +98,7 @@ struct controller { > unsigned int no_cmd_complete:1; > unsigned int link_active_reporting:1; > unsigned int notification_enabled:1; > + unsigned int use_polling:1; /* Always uses polling for this slot */ > unsigned int power_fault_detected; > }; > > diff --git a/drivers/pci/hotplug/pciehp_hpc.c > b/drivers/pci/hotplug/pciehp_hpc.c > index d7d058f..d210d23 100644 > --- a/drivers/pci/hotplug/pciehp_hpc.c > +++ b/drivers/pci/hotplug/pciehp_hpc.c > @@ -82,7 +82,7 @@ static inline int pciehp_request_irq(struct controller > *ctrl) > int retval, irq = ctrl->pcie->irq; > > /* Install interrupt polling timer. Start with 10 sec delay */ > - if (pciehp_poll_mode) { > + if (ctrl->use_polling) { > init_timer(&ctrl->poll_timer); > start_int_poll_timer(ctrl, 10); > return 0; > @@ -98,7 +98,7 @@ static inline int pciehp_request_irq(struct controller > *ctrl) > > static inline void pciehp_free_irq(struct controller *ctrl) { > - if (pciehp_poll_mode) > + if (ctrl->use_polling) > del_timer_sync(&ctrl->poll_timer); > else > free_irq(ctrl->pcie->irq, ctrl); > @@ -131,7 +131,7 @@ static int pcie_poll_cmd(struct controller *ctrl) > > static void pcie_wait_cmd(struct controller *ctrl, int poll) { > - unsigned int msecs = pciehp_poll_mode ? 2500 : 1000; > + unsigned int msecs = ctrl->use_polling ? 2500 : 1000; > unsigned long timeout = msecs_to_jiffies(msecs); > int rc; > > @@ -595,7 +595,7 @@ void pcie_enable_notification(struct controller *ctrl) > cmd |= PCI_EXP_SLTCTL_PDCE; > if (MRL_SENS(ctrl)) > cmd |= PCI_EXP_SLTCTL_MRLSCE; > - if (!pciehp_poll_mode) > + if (!ctrl->use_polling) > cmd |= PCI_EXP_SLTCTL_HPIE | PCI_EXP_SLTCTL_CCIE; > > mask = (PCI_EXP_SLTCTL_PDCE | PCI_EXP_SLTCTL_ABPE | @@ - > 642,14 +642,14 @@ int pciehp_reset_slot(struct slot *slot, int probe) > stat_mask |= PCI_EXP_SLTSTA_DLLSC; > > pcie_write_cmd(ctrl, 0, ctrl_mask); > - if (pciehp_poll_mode) > + if (ctrl->use_polling) > del_timer_sync(&ctrl->poll_timer); > > pci_reset_bridge_secondary_bus(ctrl->pcie->port); > > pcie_capability_write_word(pdev, PCI_EXP_SLTSTA, stat_mask); > pcie_write_cmd(ctrl, ctrl_mask, ctrl_mask); > - if (pciehp_poll_mode) > + if (ctrl->use_polling) > int_poll_timeout(ctrl->poll_timer.data); > > return 0; > @@ -789,6 +789,10 @@ struct controller *pcie_init(struct pcie_device *dev) > ctrl_dbg(ctrl, "Link Active Reporting supported\n"); > ctrl->link_active_reporting = 1; > } > + if (pciehp_poll_mode || dev->port->hotplug_polling) { > + ctrl_info(ctrl, "will use polling\n"); > + ctrl->use_polling = 1; > + } > > /* Clear all remaining event bits in Slot Status register */ > pcie_capability_write_word(pdev, PCI_EXP_SLTSTA, diff --git > a/include/linux/pci.h b/include/linux/pci.h index a13d682..b2ec72e 100644 > --- a/include/linux/pci.h > +++ b/include/linux/pci.h > @@ -336,6 +336,7 @@ struct pci_dev { > unsigned int is_virtfn:1; > unsigned int reset_fn:1; > unsigned int is_hotplug_bridge:1; > + unsigned int hotplug_polling:1; /* Port uses polling for hotplug */ > unsigned int __aer_firmware_first_valid:1; > unsigned int __aer_firmware_first:1; > unsigned int broken_intx_masking:1; > -- > 1.7.9.5 > > -- 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
