121 lines
3.8 KiB
C
121 lines
3.8 KiB
C
/*
|
|
* PCI IRQ handling code
|
|
*
|
|
* Copyright (c) 2008 James Bottomley <James.Bottomley@HansenPartnership.com>
|
|
* Copyright (C) 2017 Christoph Hellwig.
|
|
*/
|
|
|
|
#include <linux/acpi.h>
|
|
#include <linux/device.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/export.h>
|
|
#include <linux/pci.h>
|
|
|
|
static void pci_note_irq_problem(struct pci_dev *pdev, const char *reason)
|
|
{
|
|
struct pci_dev *parent = to_pci_dev(pdev->dev.parent);
|
|
|
|
dev_err(&pdev->dev,
|
|
"Potentially misrouted IRQ (Bridge %s %04x:%04x)\n",
|
|
dev_name(&parent->dev), parent->vendor, parent->device);
|
|
dev_err(&pdev->dev, "%s\n", reason);
|
|
dev_err(&pdev->dev, "Please report to linux-kernel@vger.kernel.org\n");
|
|
WARN_ON(1);
|
|
}
|
|
|
|
/**
|
|
* pci_lost_interrupt - reports a lost PCI interrupt
|
|
* @pdev: device whose interrupt is lost
|
|
*
|
|
* The primary function of this routine is to report a lost interrupt
|
|
* in a standard way which users can recognise (instead of blaming the
|
|
* driver).
|
|
*
|
|
* Returns:
|
|
* a suggestion for fixing it (although the driver is not required to
|
|
* act on this).
|
|
*/
|
|
enum pci_lost_interrupt_reason pci_lost_interrupt(struct pci_dev *pdev)
|
|
{
|
|
if (pdev->msi_enabled || pdev->msix_enabled) {
|
|
enum pci_lost_interrupt_reason ret;
|
|
|
|
if (pdev->msix_enabled) {
|
|
pci_note_irq_problem(pdev, "MSIX routing failure");
|
|
ret = PCI_LOST_IRQ_DISABLE_MSIX;
|
|
} else {
|
|
pci_note_irq_problem(pdev, "MSI routing failure");
|
|
ret = PCI_LOST_IRQ_DISABLE_MSI;
|
|
}
|
|
return ret;
|
|
}
|
|
#ifdef CONFIG_ACPI
|
|
if (!(acpi_disabled || acpi_noirq)) {
|
|
pci_note_irq_problem(pdev, "Potential ACPI misrouting please reboot with acpi=noirq");
|
|
/* currently no way to fix acpi on the fly */
|
|
return PCI_LOST_IRQ_DISABLE_ACPI;
|
|
}
|
|
#endif
|
|
pci_note_irq_problem(pdev, "unknown cause (not MSI or ACPI)");
|
|
return PCI_LOST_IRQ_NO_INFORMATION;
|
|
}
|
|
EXPORT_SYMBOL(pci_lost_interrupt);
|
|
|
|
/**
|
|
* pci_request_irq - allocate an interrupt line for a PCI device
|
|
* @dev: PCI device to operate on
|
|
* @nr: device-relative interrupt vector index (0-based).
|
|
* @handler: Function to be called when the IRQ occurs.
|
|
* Primary handler for threaded interrupts.
|
|
* If NULL and thread_fn != NULL the default primary handler is
|
|
* installed.
|
|
* @thread_fn: Function called from the IRQ handler thread
|
|
* If NULL, no IRQ thread is created
|
|
* @dev_id: Cookie passed back to the handler function
|
|
* @fmt: Printf-like format string naming the handler
|
|
*
|
|
* This call allocates interrupt resources and enables the interrupt line and
|
|
* IRQ handling. From the point this call is made @handler and @thread_fn may
|
|
* be invoked. All interrupts requested using this function might be shared.
|
|
*
|
|
* @dev_id must not be NULL and must be globally unique.
|
|
*/
|
|
int pci_request_irq(struct pci_dev *dev, unsigned int nr, irq_handler_t handler,
|
|
irq_handler_t thread_fn, void *dev_id, const char *fmt, ...)
|
|
{
|
|
va_list ap;
|
|
int ret;
|
|
char *devname;
|
|
|
|
va_start(ap, fmt);
|
|
devname = kvasprintf(GFP_KERNEL, fmt, ap);
|
|
va_end(ap);
|
|
|
|
ret = request_threaded_irq(pci_irq_vector(dev, nr), handler, thread_fn,
|
|
IRQF_SHARED, devname, dev_id);
|
|
if (ret)
|
|
kfree(devname);
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL(pci_request_irq);
|
|
|
|
/**
|
|
* pci_free_irq - free an interrupt allocated with pci_request_irq
|
|
* @dev: PCI device to operate on
|
|
* @nr: device-relative interrupt vector index (0-based).
|
|
* @dev_id: Device identity to free
|
|
*
|
|
* Remove an interrupt handler. The handler is removed and if the interrupt
|
|
* line is no longer in use by any driver it is disabled. The caller must
|
|
* ensure the interrupt is disabled on the device before calling this function.
|
|
* The function does not return until any executing interrupts for this IRQ
|
|
* have completed.
|
|
*
|
|
* This function must not be called from interrupt context.
|
|
*/
|
|
void pci_free_irq(struct pci_dev *dev, unsigned int nr, void *dev_id)
|
|
{
|
|
kfree(free_irq(pci_irq_vector(dev, nr), dev_id));
|
|
}
|
|
EXPORT_SYMBOL(pci_free_irq);
|