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path: root/drivers/of/irq.c
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-rw-r--r--drivers/of/irq.c276
1 files changed, 276 insertions, 0 deletions
diff --git a/drivers/of/irq.c b/drivers/of/irq.c
index 1752988..526cde6 100644
--- a/drivers/of/irq.c
+++ b/drivers/of/irq.c
@@ -79,6 +79,211 @@ 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
+ * @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. 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(const __be32 *addr, struct of_phandle_args *out_irq)
+{
+ struct device_node *ipar, *tnode, *old = NULL, *newpar = NULL;
+ __be32 initial_match_array[MAX_PHANDLE_ARGS];
+ const __be32 *match_array = initial_match_array;
+ const __be32 *tmp, *imap, *imask;
+ const __be32 dummy_imask[] = { [0 ... MAX_PHANDLE_ARGS] = ~0 };
+ u32 intsize = 1, addrsize, newintsize = 0, newaddrsize = 0;
+ int imaplen, match, i;
+
+#ifdef DEBUG
+ of_print_phandle_args("of_irq_parse_raw: ", out_irq);
+#endif
+
+ 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
+ * is none, we are nice and just walk up the tree
+ */
+ do {
+ tmp = of_get_property(ipar, "#interrupt-cells", NULL);
+ if (tmp != NULL) {
+ intsize = be32_to_cpu(*tmp);
+ break;
+ }
+ tnode = ipar;
+ ipar = of_irq_find_parent(ipar);
+ of_node_put(tnode);
+ } while (ipar);
+ if (ipar == NULL) {
+ pr_debug(" -> no parent found !\n");
+ goto fail;
+ }
+
+ pr_debug("of_irq_parse_raw: ipar=%s, size=%d\n",
+ of_node_full_name(ipar), intsize);
+
+ if (out_irq->args_count != intsize)
+ return -EINVAL;
+
+ /* Look for this #address-cells. We have to implement the old linux
+ * trick of looking for the parent here as some device-trees rely on it
+ */
+ old = of_node_get(ipar);
+ do {
+ tmp = of_get_property(old, "#address-cells", NULL);
+ tnode = of_get_parent(old);
+ of_node_put(old);
+ old = tnode;
+ } while (old && tmp == NULL);
+ of_node_put(old);
+ old = NULL;
+ addrsize = (tmp == NULL) ? 2 : be32_to_cpu(*tmp);
+
+ pr_debug(" -> addrsize=%d\n", addrsize);
+
+ /* Range check so that the temporary buffer doesn't overflow */
+ if (WARN_ON(addrsize + intsize > MAX_PHANDLE_ARGS))
+ goto fail;
+
+ /* Precalculate the match array - this simplifies match loop */
+ for (i = 0; i < addrsize; i++)
+ initial_match_array[i] = addr ? addr[i] : 0;
+ 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
+ * then we are done
+ */
+ if (of_get_property(ipar, "interrupt-controller", NULL) !=
+ NULL) {
+ pr_debug(" -> got it !\n");
+ return 0;
+ }
+
+ /*
+ * interrupt-map parsing does not work without a reg
+ * property when #address-cells != 0
+ */
+ if (addrsize && !addr) {
+ pr_debug(" -> no reg passed in when needed !\n");
+ goto fail;
+ }
+
+ /* Now look for an interrupt-map */
+ imap = of_get_property(ipar, "interrupt-map", &imaplen);
+ /* No interrupt map, check for an interrupt parent */
+ if (imap == NULL) {
+ pr_debug(" -> no map, getting parent\n");
+ newpar = of_irq_find_parent(ipar);
+ goto skiplevel;
+ }
+ imaplen /= sizeof(u32);
+
+ /* Look for a mask */
+ imask = of_get_property(ipar, "interrupt-map-mask", NULL);
+ 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 + intsize); i++, imaplen--)
+ match &= !((match_array[i] ^ *imap++) &
+ imask[i]);
+
+ pr_debug(" -> match=%d (imaplen=%d)\n", match, imaplen);
+
+ /* Get the interrupt parent */
+ if (of_irq_workarounds & OF_IMAP_NO_PHANDLE)
+ newpar = of_node_get(of_irq_dflt_pic);
+ else
+ newpar = of_find_node_by_phandle(
+ be32_to_cpup(imap));
+ imap++;
+ --imaplen;
+
+ /* Check if not found */
+ if (newpar == NULL) {
+ pr_debug(" -> imap parent not found !\n");
+ goto fail;
+ }
+
+ if (!of_device_is_available(newpar))
+ match = 0;
+
+ /* Get #interrupt-cells and #address-cells of new
+ * parent
+ */
+ tmp = of_get_property(newpar, "#interrupt-cells", NULL);
+ if (tmp == NULL) {
+ pr_debug(" -> parent lacks #interrupt-cells!\n");
+ goto fail;
+ }
+ newintsize = be32_to_cpu(*tmp);
+ tmp = of_get_property(newpar, "#address-cells", NULL);
+ newaddrsize = (tmp == NULL) ? 0 : be32_to_cpu(*tmp);
+
+ pr_debug(" -> newintsize=%d, newaddrsize=%d\n",
+ newintsize, newaddrsize);
+
+ /* Check for malformed properties */
+ if (WARN_ON(newaddrsize + newintsize >
+ MAX_PHANDLE_ARGS))
+ goto fail;
+ if (imaplen < (newaddrsize + newintsize))
+ goto fail;
+
+ imap += newaddrsize + newintsize;
+ imaplen -= newaddrsize + newintsize;
+
+ pr_debug(" -> imaplen=%d\n", imaplen);
+ }
+ if (!match)
+ goto fail;
+
+ /*
+ * Successfully parsed an interrrupt-map translation; copy new
+ * interrupt specifier into the out_irq structure
+ */
+ out_irq->np = 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;
+
+skiplevel:
+ /* Iterate again with new parent */
+ pr_debug(" -> new parent: %s\n", of_node_full_name(newpar));
+ of_node_put(ipar);
+ ipar = newpar;
+ newpar = NULL;
+ }
+ fail:
+ of_node_put(ipar);
+ of_node_put(newpar);
+
+ return -EINVAL;
+}
+EXPORT_SYMBOL_GPL(of_irq_parse_raw);
+
+/**
* of_irq_map_raw - Low level interrupt tree parsing
* @parent: the device interrupt parent
* @intspec: interrupt specifier ("interrupts" property of the device)
@@ -272,6 +477,77 @@ int of_irq_map_raw(struct device_node *parent, const __be32 *intspec,
EXPORT_SYMBOL_GPL(of_irq_map_raw);
/**
+ * 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);
+
+ /* 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);
+
+ /* Get the interrupts property */
+ intspec = of_get_property(device, "interrupts", &intlen);
+ if (intspec == NULL)
+ return -EINVAL;
+
+ 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;
+}
+EXPORT_SYMBOL_GPL(of_irq_parse_one);
+
+/**
* of_irq_map_one - Resolve an interrupt for a device
* @device: the device whose interrupt is to be resolved
* @index: index of the interrupt to resolve