of/promtree: allow DT device matching by fixing 'name' brokenness (v5)
[linux-2.6.git] / drivers / of / irq.c
index 9b3397c..75b0d3c 100644 (file)
 #include <linux/of_irq.h>
 #include <linux/string.h>
 
+/* For archs that don't support NO_IRQ (such as x86), provide a dummy value */
+#ifndef NO_IRQ
+#define NO_IRQ 0
+#endif
+
 /**
  * irq_of_parse_and_map - Parse and map an interrupt into linux virq space
  * @device: Device node of the device whose interrupt is to be mapped
@@ -43,3 +48,341 @@ unsigned int irq_of_parse_and_map(struct device_node *dev, int index)
                                     oirq.size);
 }
 EXPORT_SYMBOL_GPL(irq_of_parse_and_map);
+
+/**
+ * of_irq_find_parent - Given a device node, find its interrupt parent node
+ * @child: pointer to device node
+ *
+ * Returns a pointer to the interrupt parent node, or NULL if the interrupt
+ * parent could not be determined.
+ */
+static struct device_node *of_irq_find_parent(struct device_node *child)
+{
+       struct device_node *p;
+       const __be32 *parp;
+
+       if (!of_node_get(child))
+               return NULL;
+
+       do {
+               parp = of_get_property(child, "interrupt-parent", NULL);
+               if (parp == NULL)
+                       p = of_get_parent(child);
+               else {
+                       if (of_irq_workarounds & OF_IMAP_NO_PHANDLE)
+                               p = of_node_get(of_irq_dflt_pic);
+                       else
+                               p = of_find_node_by_phandle(be32_to_cpup(parp));
+               }
+               of_node_put(child);
+               child = p;
+       } while (p && of_get_property(p, "#interrupt-cells", NULL) == NULL);
+
+       return p;
+}
+
+/**
+ * of_irq_map_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
+ *
+ * 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.
+ */
+int of_irq_map_raw(struct device_node *parent, const __be32 *intspec,
+                  u32 ointsize, const __be32 *addr, struct of_irq *out_irq)
+{
+       struct device_node *ipar, *tnode, *old = NULL, *newpar = NULL;
+       const __be32 *tmp, *imap, *imask;
+       u32 intsize = 1, addrsize, newintsize = 0, newaddrsize = 0;
+       int imaplen, match, i;
+
+       pr_debug("of_irq_map_raw: par=%s,intspec=[0x%08x 0x%08x...],ointsize=%d\n",
+                parent->full_name, be32_to_cpup(intspec),
+                be32_to_cpup(intspec + 1), ointsize);
+
+       ipar = of_node_get(parent);
+
+       /* 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_map_raw: ipar=%s, size=%d\n", ipar->full_name, intsize);
+
+       if (ointsize != 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);
+
+       /* 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");
+                       for (i = 0; i < intsize; i++)
+                               out_irq->specifier[i] =
+                                               of_read_number(intspec +i, 1);
+                       out_irq->size = intsize;
+                       out_irq->controller = ipar;
+                       of_node_put(old);
+                       return 0;
+               }
+
+               /* 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 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;
+               }
+
+               /* Parse interrupt-map */
+               match = 0;
+               while (imaplen > (addrsize + intsize + 1) && !match) {
+                       /* Compare specifiers */
+                       match = 1;
+                       for (i = 0; i < addrsize && match; ++i) {
+                               u32 mask = imask ? imask[i] : 0xffffffffu;
+                               match = ((addr[i] ^ imap[i]) & mask) == 0;
+                       }
+                       for (; i < (addrsize + intsize) && match; ++i) {
+                               u32 mask = imask ? imask[i] : 0xffffffffu;
+                               match =
+                                  ((intspec[i-addrsize] ^ imap[i]) & mask) == 0;
+                       }
+                       imap += addrsize + intsize;
+                       imaplen -= addrsize + intsize;
+
+                       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;
+                       }
+
+                       /* 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 (imaplen < (newaddrsize + newintsize))
+                               goto fail;
+
+                       imap += newaddrsize + newintsize;
+                       imaplen -= newaddrsize + newintsize;
+
+                       pr_debug(" -> imaplen=%d\n", imaplen);
+               }
+               if (!match)
+                       goto fail;
+
+               of_node_put(old);
+               old = of_node_get(newpar);
+               addrsize = newaddrsize;
+               intsize = newintsize;
+               intspec = imap - intsize;
+               addr = intspec - addrsize;
+
+       skiplevel:
+               /* Iterate again with new parent */
+               pr_debug(" -> new parent: %s\n", newpar ? newpar->full_name : "<>");
+               of_node_put(ipar);
+               ipar = newpar;
+               newpar = NULL;
+       }
+ fail:
+       of_node_put(ipar);
+       of_node_put(old);
+       of_node_put(newpar);
+
+       return -EINVAL;
+}
+EXPORT_SYMBOL_GPL(of_irq_map_raw);
+
+/**
+ * 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
+ * @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_map_raw().
+ */
+int of_irq_map_one(struct device_node *device, int index, struct of_irq *out_irq)
+{
+       struct device_node *p;
+       const __be32 *intspec, *tmp, *addr;
+       u32 intsize, intlen;
+       int res = -EINVAL;
+
+       pr_debug("of_irq_map_one: dev=%s, index=%d\n", device->full_name, index);
+
+       /* OldWorld mac stuff is "special", handle out of line */
+       if (of_irq_workarounds & OF_IMAP_OLDWORLD_MAC)
+               return of_irq_map_oldworld(device, index, 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);
+
+       /* Get the reg property (if any) */
+       addr = of_get_property(device, "reg", NULL);
+
+       /* 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;
+
+       /* Get new specifier and map it */
+       res = of_irq_map_raw(p, intspec + index * intsize, intsize,
+                            addr, out_irq);
+ out:
+       of_node_put(p);
+       return res;
+}
+EXPORT_SYMBOL_GPL(of_irq_map_one);
+
+/**
+ * of_irq_to_resource - Decode a node's IRQ and return it as a resource
+ * @dev: pointer to device tree node
+ * @index: zero-based index of the irq
+ * @r: pointer to resource structure to return result into.
+ */
+int of_irq_to_resource(struct device_node *dev, int index, struct resource *r)
+{
+       int irq = irq_of_parse_and_map(dev, index);
+
+       /* Only dereference the resource if both the
+        * resource and the irq are valid. */
+       if (r && irq != NO_IRQ) {
+               r->start = r->end = irq;
+               r->flags = IORESOURCE_IRQ;
+               r->name = dev->full_name;
+       }
+
+       return irq;
+}
+EXPORT_SYMBOL_GPL(of_irq_to_resource);
+
+/**
+ * of_irq_count - Count the number of IRQs a node uses
+ * @dev: pointer to device tree node
+ */
+int of_irq_count(struct device_node *dev)
+{
+       int nr = 0;
+
+       while (of_irq_to_resource(dev, nr, NULL) != NO_IRQ)
+               nr++;
+
+       return nr;
+}
+
+/**
+ * of_irq_to_resource_table - Fill in resource table with node's IRQ info
+ * @dev: pointer to device tree node
+ * @res: array of resources to fill in
+ * @nr_irqs: the number of IRQs (and upper bound for num of @res elements)
+ *
+ * Returns the size of the filled in table (up to @nr_irqs).
+ */
+int of_irq_to_resource_table(struct device_node *dev, struct resource *res,
+               int nr_irqs)
+{
+       int i;
+
+       for (i = 0; i < nr_irqs; i++, res++)
+               if (of_irq_to_resource(dev, i, res) == NO_IRQ)
+                       break;
+
+       return i;
+}