/**
* of_irq_parse_one - Resolve an interrupt for a device
* @device: the device whose interrupt is to be resolved
* @index: index of the interrupt to resolve
* @out_irq: structure of_irq filled by this function
*
* This function resolves an interrupt for a node by walking the interrupt tree,
* finding which interrupt controller node it is attached to, and returning the
* interrupt specifier that can be used to retrieve a Linux IRQ number.
*/
int of_irq_parse_one(struct device_node *device, int index, struct of_phandle_args *out_irq)
{
struct device_node *p;
const __be32 *intspec, *tmp, *addr;
u32 intsize, intlen;
int i, res = -EINVAL;
pr_debug("of_irq_parse_one: dev=%s, index=%d\n", of_node_full_name(device), index);
/* OldWorld mac stuff is "special", handle out of line */
if (of_irq_workarounds & OF_IMAP_OLDWORLD_MAC)
return of_irq_parse_oldworld(device, index, out_irq);
/* Get the reg property (if any) */
addr = of_get_property(device, "reg", NULL);
/* Get the interrupts property */
intspec = of_get_property(device, "interrupts", &intlen);
if (intspec == NULL) {
/* Try the new-style interrupts-extended */
res = of_parse_phandle_with_args(device, "interrupts-extended",
"#interrupt-cells", index, out_irq);
if (res)
return -EINVAL;
return of_irq_parse_raw(addr, out_irq);
}
intlen /= sizeof(*intspec);
pr_debug(" intspec=%d intlen=%d\n", be32_to_cpup(intspec), intlen);
/* Look for the interrupt parent. */
p = of_irq_find_parent(device);
if (p == NULL)
return -EINVAL;
/* Get size of interrupt specifier */
tmp = of_get_property(p, "#interrupt-cells", NULL);
if (tmp == NULL)
goto out;
intsize = be32_to_cpu(*tmp);
pr_debug(" intsize=%d intlen=%d\n", intsize, intlen);
/* Check index */
if ((index + 1) * intsize > intlen)
goto out;
/* Copy intspec into irq structure */
intspec += index * intsize;
out_irq->np = p;
out_irq->args_count = intsize;
for (i = 0; i < intsize; i++)
out_irq->args[i] = be32_to_cpup(intspec++);
/* Check if there are any interrupt-map translations to process */
res = of_irq_parse_raw(addr, out_irq);
out:
of_node_put(p);
return res;
}
/**
* of_irq_parse_one - Resolve an interrupt for a device
* @device: the device whose interrupt is to be resolved
* @index: index of the interrupt to resolve
* @out_irq: structure of_irq filled by this function
*
* This function resolves an interrupt for a node by walking the interrupt tree,
* finding which interrupt controller node it is attached to, and returning the
* interrupt specifier that can be used to retrieve a Linux IRQ number.
*/
int of_irq_parse_one(struct device_node *device, int index, struct of_phandle_args *out_irq)
{
struct device_node *p;
const __be32 *addr;
u32 intsize;
int i, res;
pr_debug("of_irq_parse_one: dev=%pOF, index=%d\n", device, index);
/* OldWorld mac stuff is "special", handle out of line */
if (of_irq_workarounds & OF_IMAP_OLDWORLD_MAC)
return of_irq_parse_oldworld(device, index, out_irq);
/* Get the reg property (if any) */
addr = of_get_property(device, "reg", NULL);
/* Try the new-style interrupts-extended first */
res = of_parse_phandle_with_args(device, "interrupts-extended",
"#interrupt-cells", index, out_irq);
if (!res)
return of_irq_parse_raw(addr, out_irq);
/* Look for the interrupt parent. */
p = of_irq_find_parent(device);
if (p == NULL)
return -EINVAL;
/* Get size of interrupt specifier */
if (of_property_read_u32(p, "#interrupt-cells", &intsize)) {
res = -EINVAL;
goto out;
}
pr_debug(" parent=%pOF, intsize=%d\n", p, intsize);
/* Copy intspec into irq structure */
out_irq->np = p;
out_irq->args_count = intsize;
for (i = 0; i < intsize; i++) {
res = of_property_read_u32_index(device, "interrupts",
(index * intsize) + i,
out_irq->args + i);
if (res)
goto out;
}
pr_debug(" intspec=%d\n", *out_irq->args);
/* Check if there are any interrupt-map translations to process */
res = of_irq_parse_raw(addr, out_irq);
out:
of_node_put(p);
return res;
}
/**
* 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;
u32 lspec;
__be32 lspec_be;
__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)
return rc;
/* No pin, exit */
if (pin == 0)
return -ENODEV;
/* Now we walk up the PCI tree */
lspec = pin;
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)
return -EINVAL;
} 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
*/
lspec = pci_swizzle_interrupt_pin(pdev, lspec);
pdev = ppdev;
}
out_irq->np = ppnode;
out_irq->args_count = 1;
out_irq->args[0] = lspec;
lspec_be = cpu_to_be32(lspec);
laddr[0] = cpu_to_be32((pdev->bus->number << 16) | (pdev->devfn << 8));
laddr[1] = laddr[2] = cpu_to_be32(0);
return of_irq_parse_raw(laddr, out_irq);
}