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Release 4.14 drivers/of/of_pci_irq.c

Directory: drivers/of
#include <linux/kernel.h>
#include <linux/of_pci.h>
#include <linux/of_irq.h>
#include <linux/export.h>

 * of_irq_parse_pci - Resolve the interrupt for a PCI device
 * @pdev:       the device whose interrupt is to be resolved
 * @out_irq:    structure of_irq filled by this function
 * This function resolves the PCI interrupt for a given PCI device. If a
 * device-node exists for a given pci_dev, it will use normal OF tree
 * walking. If not, it will implement standard swizzling and walk up the
 * PCI tree until an device-node is found, at which point it will finish
 * resolving using the OF tree walking.

int of_irq_parse_pci(const struct pci_dev *pdev, struct of_phandle_args *out_irq) { struct device_node *dn, *ppnode; struct pci_dev *ppdev; __be32 laddr[3]; u8 pin; int rc; /* Check if we have a device node, if yes, fallback to standard * device tree parsing */ dn = pci_device_to_OF_node(pdev); if (dn) { rc = of_irq_parse_one(dn, 0, out_irq); if (!rc) return rc; } /* Ok, we don't, time to have fun. Let's start by building up an * interrupt spec. we assume #interrupt-cells is 1, which is standard * for PCI. If you do different, then don't use that routine. */ rc = pci_read_config_byte(pdev, PCI_INTERRUPT_PIN, &pin); if (rc != 0) goto err; /* No pin, exit with no error message. */ if (pin == 0) return -ENODEV; /* Now we walk up the PCI tree */ for (;;) { /* Get the pci_dev of our parent */ ppdev = pdev->bus->self; /* Ouch, it's a host bridge... */ if (ppdev == NULL) { ppnode = pci_bus_to_OF_node(pdev->bus); /* No node for host bridge ? give up */ if (ppnode == NULL) { rc = -EINVAL; goto err; } } else { /* We found a P2P bridge, check if it has a node */ ppnode = pci_device_to_OF_node(ppdev); } /* Ok, we have found a parent with a device-node, hand over to * the OF parsing code. * We build a unit address from the linux device to be used for * resolution. Note that we use the linux bus number which may * not match your firmware bus numbering. * Fortunately, in most cases, interrupt-map-mask doesn't * include the bus number as part of the matching. * You should still be careful about that though if you intend * to rely on this function (you ship a firmware that doesn't * create device nodes for all PCI devices). */ if (ppnode) break; /* We can only get here if we hit a P2P bridge with no node, * let's do standard swizzling and try again */ pin = pci_swizzle_interrupt_pin(pdev, pin); pdev = ppdev; } out_irq->np = ppnode; out_irq->args_count = 1; out_irq->args[0] = pin; laddr[0] = cpu_to_be32((pdev->bus->number << 16) | (pdev->devfn << 8)); laddr[1] = laddr[2] = cpu_to_be32(0); rc = of_irq_parse_raw(laddr, out_irq); if (rc) goto err; return 0; err: if (rc == -ENOENT) { dev_warn(&pdev->dev, "%s: no interrupt-map found, INTx interrupts not available\n", __func__); pr_warn_once("%s: possibly some PCI slots don't have level triggered interrupts capability\n", __func__); } else { dev_err(&pdev->dev, "%s: failed with rc=%d\n", __func__, rc); } return rc; }


Benjamin Herrenschmidt21968.22%112.50%
David Daney4012.46%112.50%
Guilherme G. Piccoli3410.59%112.50%
Grant C. Likely247.48%337.50%
Sergei Shtylyov30.93%112.50%
John Crispin10.31%112.50%

EXPORT_SYMBOL_GPL(of_irq_parse_pci); /** * of_irq_parse_and_map_pci() - Decode a PCI irq from the device tree and map to a virq * @dev: The pci device needing an irq * @slot: PCI slot number; passed when used as map_irq callback. Unused * @pin: PCI irq pin number; passed when used as map_irq callback. Unused * * @slot and @pin are unused, but included in the function so that this * function can be used directly as the map_irq callback to * pci_assign_irq() and struct pci_host_bridge.map_irq pointer */
int of_irq_parse_and_map_pci(const struct pci_dev *dev, u8 slot, u8 pin) { struct of_phandle_args oirq; int ret; ret = of_irq_parse_pci(dev, &oirq); if (ret) return 0; /* Proper return code 0 == NO_IRQ */ return irq_create_of_mapping(&oirq); }


Grant C. Likely4591.84%150.00%
Benjamin Herrenschmidt48.16%150.00%


Overall Contributors

Benjamin Herrenschmidt24261.42%19.09%
Grant C. Likely7218.27%436.36%
David Daney4010.15%19.09%
Guilherme G. Piccoli348.63%19.09%
Sergei Shtylyov30.76%19.09%
John Crispin10.25%19.09%
Paul Gortmaker10.25%19.09%
Matthew Minter10.25%19.09%
Directory: drivers/of
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