Commit 23616132 authored by Grant Likely's avatar Grant Likely
Browse files

of/irq: Refactor interrupt-map parsing 



All the users of of_irq_parse_raw pass in a raw interrupt specifier from
the device tree and expect it to be returned (possibly modified) in an
of_phandle_args structure. However, the primary function of
of_irq_parse_raw() is to check for translations due to the presence of
one or more interrupt-map properties. The actual placing of the data
into an of_phandle_args structure is trivial. If it is refactored to
accept an of_phandle_args structure directly, then it becomes possible
to consume of_phandle_args from other sources. This is important for an
upcoming patch that allows a device to be connected to more than one
interrupt parent. It also simplifies the code a bit.

The biggest complication with this patch is that the old version works
on the interrupt specifiers in __be32 form, but the of_phandle_args
structure is intended to carry it in the cpu-native version. A bit of
churn was required to make this work. In the end it results in tighter
code, so the churn is worth it.

Signed-off-by: default avatarGrant Likely <grant.likely@linaro.org>
Acked-by: default avatarTony Lindgren <tony@atomide.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
parent e6d30ab1

arch/powerpc/platforms/fsl_uli1575.c

+4 −2
Original line number Diff line number Diff line
@@ -322,7 +322,6 @@ static void hpcd_final_uli5288(struct pci_dev *dev) 
	struct pci_controller *hose = pci_bus_to_host(dev->bus);

	struct device_node *hosenode = hose ? hose->dn : NULL;

	struct of_phandle_args oirq;

	int pin = 2;

	u32 laddr[3];



	if (!machine_is(mpc86xx_hpcd))
@@ -331,9 +330,12 @@ static void hpcd_final_uli5288(struct pci_dev *dev) 
	if (!hosenode)

		return;



	oirq.np = hosenode;

	oirq.args[0] = 2;

	oirq.args_count = 1;

	laddr[0] = (hose->first_busno << 16) | (PCI_DEVFN(31, 0) << 8);

	laddr[1] = laddr[2] = 0;

	of_irq_parse_raw(hosenode, &pin, 1, laddr, &oirq);

	of_irq_parse_raw(laddr, &oirq);

	dev->irq = irq_create_of_mapping(&oirq);

}

drivers/of/irq.c

+57 −51
Original line number Diff line number Diff line
@@ -80,31 +80,32 @@ struct device_node *of_irq_find_parent(struct device_node *child) 
/**

 * of_irq_parse_raw - Low level interrupt tree parsing

 * @parent:	the device interrupt parent

 * @intspec:	interrupt specifier ("interrupts" property of the device)

 * @ointsize:   size of the passed in interrupt specifier

 * @addr:	address specifier (start of "reg" property of the device)

 * @out_irq:	structure of_irq filled by this function

 * @addr:	address specifier (start of "reg" property of the device) in be32 format

 * @out_irq:	structure of_irq updated by this function

 *

 * Returns 0 on success and a negative number on error

 *

 * This function is a low-level interrupt tree walking function. It

 * can be used to do a partial walk with synthetized reg and interrupts

 * properties, for example when resolving PCI interrupts when no device

 * node exist for the parent.

 * node exist for the parent. It takes an interrupt specifier structure as

 * input, walks the tree looking for any interrupt-map properties, translates

 * the specifier for each map, and then returns the translated map.

 */

int of_irq_parse_raw(struct device_node *parent, const __be32 *intspec,

		   u32 ointsize, const __be32 *addr, struct of_phandle_args *out_irq)

int of_irq_parse_raw(const __be32 *addr, struct of_phandle_args *out_irq)

{

	struct device_node *ipar, *tnode, *old = NULL, *newpar = NULL;

	const __be32 *tmp, *imap, *imask;

	__be32 initial_match_array[8];

	const __be32 *match_array = initial_match_array;

	const __be32 *tmp, *imap, *imask, dummy_imask[] = { ~0, ~0, ~0, ~0, ~0 };

	u32 intsize = 1, addrsize, newintsize = 0, newaddrsize = 0;

	int imaplen, match, i;



	pr_debug("of_irq_parse_raw: par=%s,intspec=[0x%08x 0x%08x...],ointsize=%d\n",

		 of_node_full_name(parent), be32_to_cpup(intspec),

		 be32_to_cpup(intspec + 1), ointsize);

		 of_node_full_name(out_irq->np), out_irq->args[0], out_irq->args[1],

		 out_irq->args_count);



	ipar = of_node_get(parent);

	ipar = of_node_get(out_irq->np);



	/* First get the #interrupt-cells property of the current cursor

	 * that tells us how to interpret the passed-in intspec. If there
@@ -127,7 +128,7 @@ int of_irq_parse_raw(struct device_node *parent, const __be32 *intspec, 


	pr_debug("of_irq_parse_raw: ipar=%s, size=%d\n", of_node_full_name(ipar), intsize);



	if (ointsize != intsize)

	if (out_irq->args_count != intsize)

		return -EINVAL;



	/* Look for this #address-cells. We have to implement the old linux
@@ -146,6 +147,21 @@ int of_irq_parse_raw(struct device_node *parent, const __be32 *intspec, 


	pr_debug(" -> addrsize=%d\n", addrsize);



	/* If we were passed no "reg" property and we attempt to parse

	 * an interrupt-map, then #address-cells must be 0.

	 * Fail if it's not.

	 */

	if (addr == NULL && addrsize != 0) {

		pr_debug(" -> no reg passed in when needed !\n");

		return -EINVAL;

	}



	/* Precalculate the match array - this simplifies match loop */

	for (i = 0; i < addrsize; i++)

		initial_match_array[i] = addr[i];

	for (i = 0; i < intsize; i++)

		initial_match_array[addrsize + i] = cpu_to_be32(out_irq->args[i]);



	/* Now start the actual "proper" walk of the interrupt tree */

	while (ipar != NULL) {

		/* Now check if cursor is an interrupt-controller and if it is
@@ -154,11 +170,6 @@ int of_irq_parse_raw(struct device_node *parent, const __be32 *intspec, 
		if (of_get_property(ipar, "interrupt-controller", NULL) !=

				NULL) {

			pr_debug(" -> got it !\n");

			for (i = 0; i < intsize; i++)

				out_irq->args[i] =

						of_read_number(intspec +i, 1);

			out_irq->args_count = intsize;

			out_irq->np = ipar;

			of_node_put(old);

			return 0;

		}
@@ -175,34 +186,16 @@ int of_irq_parse_raw(struct device_node *parent, const __be32 *intspec, 


		/* Look for a mask */

		imask = of_get_property(ipar, "interrupt-map-mask", NULL);



		/* If we were passed no "reg" property and we attempt to parse

		 * an interrupt-map, then #address-cells must be 0.

		 * Fail if it's not.

		 */

		if (addr == NULL && addrsize != 0) {

			pr_debug(" -> no reg passed in when needed !\n");

			goto fail;

		}

		if (!imask)

			imask = dummy_imask;



		/* Parse interrupt-map */

		match = 0;

		while (imaplen > (addrsize + intsize + 1) && !match) {

			/* Compare specifiers */

			match = 1;

			for (i = 0; i < addrsize && match; ++i) {

				__be32 mask = imask ? imask[i]

						    : cpu_to_be32(0xffffffffu);

				match = ((addr[i] ^ imap[i]) & mask) == 0;

			}

			for (; i < (addrsize + intsize) && match; ++i) {

				__be32 mask = imask ? imask[i]

						    : cpu_to_be32(0xffffffffu);

				match =

				   ((intspec[i-addrsize] ^ imap[i]) & mask) == 0;

			}

			imap += addrsize + intsize;

			imaplen -= addrsize + intsize;

			for (i = 0; i < (addrsize + intsize); i++, imaplen--)

				match = !((match_array[i] ^ *imap++) & imask[i]);



			pr_debug(" -> match=%d (imaplen=%d)\n", match, imaplen);
@@ -247,12 +240,18 @@ int of_irq_parse_raw(struct device_node *parent, const __be32 *intspec, 
		if (!match)

			goto fail;



		of_node_put(old);

		old = of_node_get(newpar);

		/*

		 * Successfully parsed an interrrupt-map translation; copy new

		 * interrupt specifier into the out_irq structure

		 */

		of_node_put(out_irq->np);

		out_irq->np = of_node_get(newpar);



		match_array = imap - newaddrsize - newintsize;

		for (i = 0; i < newintsize; i++)

			out_irq->args[i] = be32_to_cpup(imap - newintsize + i);

		out_irq->args_count = intsize = newintsize;

		addrsize = newaddrsize;

		intsize = newintsize;

		intspec = imap - intsize;

		addr = intspec - addrsize;



	skiplevel:

		/* Iterate again with new parent */
@@ -263,7 +262,7 @@ int of_irq_parse_raw(struct device_node *parent, const __be32 *intspec, 
	}

 fail:

	of_node_put(ipar);

	of_node_put(old);

	of_node_put(out_irq->np);

	of_node_put(newpar);



	return -EINVAL;
@@ -276,15 +275,16 @@ EXPORT_SYMBOL_GPL(of_irq_parse_raw); 
 * @index: index of the interrupt to resolve

 * @out_irq: structure of_irq filled by this function

 *

 * This function resolves an interrupt, walking the tree, for a given

 * device-tree node. It's the high level pendant to of_irq_parse_raw().

 * 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 res = -EINVAL;

	int i, res = -EINVAL;



	pr_debug("of_irq_parse_one: dev=%s, index=%d\n", of_node_full_name(device), index);
@@ -320,9 +320,15 @@ int of_irq_parse_one(struct device_node *device, int index, struct of_phandle_ar 
	if ((index + 1) * intsize > intlen)

		goto out;



	/* Get new specifier and map it */

	res = of_irq_parse_raw(p, intspec + index * intsize, intsize,

			     addr, out_irq);

	/* 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;

drivers/of/of_pci_irq.c

+5 −2
Original line number Diff line number Diff line
@@ -85,9 +85,12 @@ int of_irq_parse_pci(const struct pci_dev *pdev, struct of_phandle_args *out_irq 
		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(ppnode, &lspec_be, 1, laddr, out_irq);

	return of_irq_parse_raw(laddr, out_irq);

}

EXPORT_SYMBOL_GPL(of_irq_parse_pci);

include/linux/of_irq.h

+1 −4
Original line number Diff line number Diff line
@@ -31,10 +31,7 @@ static inline int of_irq_parse_oldworld(struct device_node *device, int index, 
}

#endif /* CONFIG_PPC32 && CONFIG_PPC_PMAC */





extern int of_irq_parse_raw(struct device_node *parent, const __be32 *intspec,

			  u32 ointsize, const __be32 *addr,

			  struct of_phandle_args *out_irq);

extern int of_irq_parse_raw(const __be32 *addr, struct of_phandle_args *out_irq);

extern int of_irq_parse_one(struct device_node *device, int index,

			  struct of_phandle_args *out_irq);

extern unsigned int irq_create_of_mapping(struct of_phandle_args *irq_data);

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