/**
 * 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;
}
示例#2
0
文件: irq.c 项目: Lyude/linux
/**
 * 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;
}
示例#3
0
文件: of_pci_irq.c 项目: 7799/linux
/**
 * 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);
}