diff options
Diffstat (limited to 'drivers/pci')
| -rw-r--r-- | drivers/pci/hotplug/pciehp.h | 3 | ||||
| -rw-r--r-- | drivers/pci/hotplug/pciehp_hpc.c | 70 |
2 files changed, 41 insertions, 32 deletions
diff --git a/drivers/pci/hotplug/pciehp.h b/drivers/pci/hotplug/pciehp.h index c3d63e5b650f..ab1d97a1822d 100644 --- a/drivers/pci/hotplug/pciehp.h +++ b/drivers/pci/hotplug/pciehp.h @@ -112,6 +112,8 @@ struct event_info { * @notification_enabled: whether the IRQ was requested successfully * @power_fault_detected: whether a power fault was detected by the hardware * that has not yet been cleared by the user + * @pending_events: used by the IRQ handler to save events retrieved from the + * Slot Status register for later consumption by the IRQ thread */ struct controller { struct mutex ctrl_lock; @@ -126,6 +128,7 @@ struct controller { unsigned int link_active_reporting:1; unsigned int notification_enabled:1; unsigned int power_fault_detected; + atomic_t pending_events; }; #define INT_PRESENCE_ON 1 diff --git a/drivers/pci/hotplug/pciehp_hpc.c b/drivers/pci/hotplug/pciehp_hpc.c index aff191b4552c..4ffaa3dfeb89 100644 --- a/drivers/pci/hotplug/pciehp_hpc.c +++ b/drivers/pci/hotplug/pciehp_hpc.c @@ -31,7 +31,8 @@ static inline struct pci_dev *ctrl_dev(struct controller *ctrl) return ctrl->pcie->port; } -static irqreturn_t pcie_isr(int irq, void *dev_id); +static irqreturn_t pciehp_isr(int irq, void *dev_id); +static irqreturn_t pciehp_ist(int irq, void *dev_id); static void start_int_poll_timer(struct controller *ctrl, int sec); /* This is the interrupt polling timeout function. */ @@ -40,7 +41,8 @@ static void int_poll_timeout(struct timer_list *t) struct controller *ctrl = from_timer(ctrl, t, poll_timer); /* Poll for interrupt events. regs == NULL => polling */ - pcie_isr(0, ctrl); + while (pciehp_isr(IRQ_NOTCONNECTED, ctrl) == IRQ_WAKE_THREAD) + pciehp_ist(IRQ_NOTCONNECTED, ctrl); if (!pciehp_poll_time) pciehp_poll_time = 2; /* default polling interval is 2 sec */ @@ -71,7 +73,8 @@ static inline int pciehp_request_irq(struct controller *ctrl) } /* Installs the interrupt handler */ - retval = request_irq(irq, pcie_isr, IRQF_SHARED, MY_NAME, ctrl); + retval = request_threaded_irq(irq, pciehp_isr, pciehp_ist, + IRQF_SHARED, MY_NAME, ctrl); if (retval) ctrl_err(ctrl, "Cannot get irq %d for the hotplug controller\n", irq); @@ -539,12 +542,11 @@ static irqreturn_t pciehp_isr(int irq, void *dev_id) { struct controller *ctrl = (struct controller *)dev_id; struct pci_dev *pdev = ctrl_dev(ctrl); - struct slot *slot = ctrl->slot; u16 status, events; - u8 present; - bool link; - /* Interrupts cannot originate from a controller that's asleep */ + /* + * Interrupts only occur in D3hot or shallower (PCIe r4.0, sec 6.7.3.4). + */ if (pdev->current_state == PCI_D3cold) return IRQ_NONE; @@ -572,18 +574,22 @@ static irqreturn_t pciehp_isr(int irq, void *dev_id) if (!events) return IRQ_NONE; - /* Capture link status before clearing interrupts */ - if (events & PCI_EXP_SLTSTA_DLLSC) - link = pciehp_check_link_active(ctrl); - pcie_capability_write_word(pdev, PCI_EXP_SLTSTA, events); ctrl_dbg(ctrl, "pending interrupts %#06x from Slot Status\n", events); - /* Check Command Complete Interrupt Pending */ + /* + * Command Completed notifications are not deferred to the + * IRQ thread because it may be waiting for their arrival. + */ if (events & PCI_EXP_SLTSTA_CC) { ctrl->cmd_busy = 0; smp_mb(); wake_up(&ctrl->queue); + + if (events == PCI_EXP_SLTSTA_CC) + return IRQ_HANDLED; + + events &= ~PCI_EXP_SLTSTA_CC; } if (pdev->ignore_hotplug) { @@ -591,6 +597,24 @@ static irqreturn_t pciehp_isr(int irq, void *dev_id) return IRQ_HANDLED; } + /* Save pending events for consumption by IRQ thread. */ + atomic_or(events, &ctrl->pending_events); + return IRQ_WAKE_THREAD; +} + +static irqreturn_t pciehp_ist(int irq, void *dev_id) +{ + struct controller *ctrl = (struct controller *)dev_id; + struct slot *slot = ctrl->slot; + u32 events; + u8 present; + bool link; + + synchronize_hardirq(irq); + events = atomic_xchg(&ctrl->pending_events, 0); + if (!events) + return IRQ_NONE; + /* Check Attention Button Pressed */ if (events & PCI_EXP_SLTSTA_ABP) { ctrl_info(ctrl, "Slot(%s): Attention button pressed\n", @@ -605,12 +629,13 @@ static irqreturn_t pciehp_isr(int irq, void *dev_id) * and cause the wrong event to queue. */ if (events & PCI_EXP_SLTSTA_DLLSC) { + link = pciehp_check_link_active(ctrl); ctrl_info(ctrl, "Slot(%s): Link %s\n", slot_name(slot), link ? "Up" : "Down"); pciehp_queue_interrupt_event(slot, link ? INT_LINK_UP : INT_LINK_DOWN); } else if (events & PCI_EXP_SLTSTA_PDC) { - present = !!(status & PCI_EXP_SLTSTA_PDS); + pciehp_get_adapter_status(slot, &present); ctrl_info(ctrl, "Slot(%s): Card %spresent\n", slot_name(slot), present ? "" : "not "); pciehp_queue_interrupt_event(slot, present ? INT_PRESENCE_ON : @@ -627,25 +652,6 @@ static irqreturn_t pciehp_isr(int irq, void *dev_id) return IRQ_HANDLED; } -static irqreturn_t pcie_isr(int irq, void *dev_id) -{ - irqreturn_t rc, handled = IRQ_NONE; - - /* - * To guarantee that all interrupt events are serviced, we need to - * re-inspect Slot Status register after clearing what is presumed - * to be the last pending interrupt. - */ - do { - rc = pciehp_isr(irq, dev_id); - if (rc == IRQ_HANDLED) - handled = IRQ_HANDLED; - } while (rc == IRQ_HANDLED); - - /* Return IRQ_HANDLED if we handled one or more events */ - return handled; -} - static void pcie_enable_notification(struct controller *ctrl) { u16 cmd, mask; |