diff options
Diffstat (limited to 'drivers/pci')
| -rw-r--r-- | drivers/pci/hotplug/pciehp.h | 5 | ||||
| -rw-r--r-- | drivers/pci/hotplug/pciehp_hpc.c | 45 |
2 files changed, 48 insertions, 2 deletions
diff --git a/drivers/pci/hotplug/pciehp.h b/drivers/pci/hotplug/pciehp.h index 247681963063..811cf83f956d 100644 --- a/drivers/pci/hotplug/pciehp.h +++ b/drivers/pci/hotplug/pciehp.h @@ -156,8 +156,13 @@ struct controller { * * %DISABLE_SLOT: Disable the slot in response to a user request via sysfs or * an Attention Button press after the 5 second delay + * %RERUN_ISR: Used by the IRQ handler to inform the IRQ thread that the + * hotplug port was inaccessible when the interrupt occurred, requiring + * that the IRQ handler is rerun by the IRQ thread after it has made the + * hotplug port accessible by runtime resuming its parents to D0 */ #define DISABLE_SLOT (1 << 16) +#define RERUN_ISR (1 << 17) #define ATTN_BUTTN(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_ABP) #define POWER_CTRL(ctrl) ((ctrl)->slot_cap & PCI_EXP_SLTCAP_PCP) diff --git a/drivers/pci/hotplug/pciehp_hpc.c b/drivers/pci/hotplug/pciehp_hpc.c index 6313ddf38a51..6e9b4330ad82 100644 --- a/drivers/pci/hotplug/pciehp_hpc.c +++ b/drivers/pci/hotplug/pciehp_hpc.c @@ -19,6 +19,7 @@ #include <linux/jiffies.h> #include <linux/kthread.h> #include <linux/pci.h> +#include <linux/pm_runtime.h> #include <linux/interrupt.h> #include <linux/time.h> #include <linux/slab.h> @@ -521,6 +522,7 @@ 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 device *parent = pdev->dev.parent; u16 status, events; /* @@ -529,9 +531,26 @@ static irqreturn_t pciehp_isr(int irq, void *dev_id) if (pdev->current_state == PCI_D3cold) return IRQ_NONE; + /* + * Keep the port accessible by holding a runtime PM ref on its parent. + * Defer resume of the parent to the IRQ thread if it's suspended. + * Mask the interrupt until then. + */ + if (parent) { + pm_runtime_get_noresume(parent); + if (!pm_runtime_active(parent)) { + pm_runtime_put(parent); + disable_irq_nosync(irq); + atomic_or(RERUN_ISR, &ctrl->pending_events); + return IRQ_WAKE_THREAD; + } + } + pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &status); if (status == (u16) ~0) { ctrl_info(ctrl, "%s: no response from device\n", __func__); + if (parent) + pm_runtime_put(parent); return IRQ_NONE; } @@ -550,11 +569,16 @@ static irqreturn_t pciehp_isr(int irq, void *dev_id) if (ctrl->power_fault_detected) events &= ~PCI_EXP_SLTSTA_PFD; - if (!events) + if (!events) { + if (parent) + pm_runtime_put(parent); return IRQ_NONE; + } pcie_capability_write_word(pdev, PCI_EXP_SLTSTA, events); ctrl_dbg(ctrl, "pending interrupts %#06x from Slot Status\n", events); + if (parent) + pm_runtime_put(parent); /* * Command Completed notifications are not deferred to the @@ -584,13 +608,29 @@ static irqreturn_t pciehp_isr(int irq, void *dev_id) static irqreturn_t pciehp_ist(int irq, void *dev_id) { struct controller *ctrl = (struct controller *)dev_id; + struct pci_dev *pdev = ctrl_dev(ctrl); struct slot *slot = ctrl->slot; + irqreturn_t ret; u32 events; + pci_config_pm_runtime_get(pdev); + + /* rerun pciehp_isr() if the port was inaccessible on interrupt */ + if (atomic_fetch_and(~RERUN_ISR, &ctrl->pending_events) & RERUN_ISR) { + ret = pciehp_isr(irq, dev_id); + enable_irq(irq); + if (ret != IRQ_WAKE_THREAD) { + pci_config_pm_runtime_put(pdev); + return ret; + } + } + synchronize_hardirq(irq); events = atomic_xchg(&ctrl->pending_events, 0); - if (!events) + if (!events) { + pci_config_pm_runtime_put(pdev); return IRQ_NONE; + } /* Check Attention Button Pressed */ if (events & PCI_EXP_SLTSTA_ABP) { @@ -618,6 +658,7 @@ static irqreturn_t pciehp_ist(int irq, void *dev_id) pciehp_green_led_off(slot); } + pci_config_pm_runtime_put(pdev); wake_up(&ctrl->requester); return IRQ_HANDLED; } |
