}
#ifdef CONFIG_PCI_DOMAINS_GENERIC
-static atomic_t __domain_nr = ATOMIC_INIT(-1);
+static DEFINE_IDA(pci_domain_nr_static_ida);
+static DEFINE_IDA(pci_domain_nr_dynamic_ida);
-static int pci_get_new_domain_nr(void)
+static void of_pci_reserve_static_domain_nr(void)
{
- return atomic_inc_return(&__domain_nr);
+ struct device_node *np;
+ int domain_nr;
+
+ for_each_node_by_type(np, "pci") {
+ domain_nr = of_get_pci_domain_nr(np);
+ if (domain_nr < 0)
+ continue;
+ /*
+ * Permanently allocate domain_nr in dynamic_ida
+ * to prevent it from dynamic allocation.
+ */
+ ida_alloc_range(&pci_domain_nr_dynamic_ida,
+ domain_nr, domain_nr, GFP_KERNEL);
+ }
}
static int of_pci_bus_find_domain_nr(struct device *parent)
{
- static int use_dt_domains = -1;
- int domain = -1;
+ static bool static_domains_reserved = false;
+ int domain_nr;
- if (parent)
- domain = of_get_pci_domain_nr(parent->of_node);
+ /* On the first call scan device tree for static allocations. */
+ if (!static_domains_reserved) {
+ of_pci_reserve_static_domain_nr();
+ static_domains_reserved = true;
+ }
+
+ if (parent) {
+ /*
+ * If domain is in DT, allocate it in static IDA. This
+ * prevents duplicate static allocations in case of errors
+ * in DT.
+ */
+ domain_nr = of_get_pci_domain_nr(parent->of_node);
+ if (domain_nr >= 0)
+ return ida_alloc_range(&pci_domain_nr_static_ida,
+ domain_nr, domain_nr,
+ GFP_KERNEL);
+ }
/*
- * Check DT domain and use_dt_domains values.
- *
- * If DT domain property is valid (domain >= 0) and
- * use_dt_domains != 0, the DT assignment is valid since this means
- * we have not previously allocated a domain number by using
- * pci_get_new_domain_nr(); we should also update use_dt_domains to
- * 1, to indicate that we have just assigned a domain number from
- * DT.
- *
- * If DT domain property value is not valid (ie domain < 0), and we
- * have not previously assigned a domain number from DT
- * (use_dt_domains != 1) we should assign a domain number by
- * using the:
- *
- * pci_get_new_domain_nr()
- *
- * API and update the use_dt_domains value to keep track of method we
- * are using to assign domain numbers (use_dt_domains = 0).
- *
- * All other combinations imply we have a platform that is trying
- * to mix domain numbers obtained from DT and pci_get_new_domain_nr(),
- * which is a recipe for domain mishandling and it is prevented by
- * invalidating the domain value (domain = -1) and printing a
- * corresponding error.
+ * If domain was not specified in DT, choose a free ID from dynamic
+ * allocations. All domain numbers from DT are permanently in
+ * dynamic allocations to prevent assigning them to other DT nodes
+ * without static domain.
*/
- if (domain >= 0 && use_dt_domains) {
- use_dt_domains = 1;
- } else if (domain < 0 && use_dt_domains != 1) {
- use_dt_domains = 0;
- domain = pci_get_new_domain_nr();
- } else {
- if (parent)
- pr_err("Node %pOF has ", parent->of_node);
- pr_err("Inconsistent \"linux,pci-domain\" property in DT\n");
- domain = -1;
- }
+ return ida_alloc(&pci_domain_nr_dynamic_ida, GFP_KERNEL);
+}
- return domain;
+static void of_pci_bus_release_domain_nr(struct pci_bus *bus, struct device *parent)
+{
+ if (bus->domain_nr < 0)
+ return;
+
+ /* Release domain from IDA where it was allocated. */
+ if (of_get_pci_domain_nr(parent->of_node) == bus->domain_nr)
+ ida_free(&pci_domain_nr_static_ida, bus->domain_nr);
+ else
+ ida_free(&pci_domain_nr_dynamic_ida, bus->domain_nr);
}
int pci_bus_find_domain_nr(struct pci_bus *bus, struct device *parent)
return acpi_disabled ? of_pci_bus_find_domain_nr(parent) :
acpi_pci_bus_find_domain_nr(bus);
}
+
+void pci_bus_release_domain_nr(struct pci_bus *bus, struct device *parent)
+{
+ if (!acpi_disabled)
+ return;
+ of_pci_bus_release_domain_nr(bus, parent);
+}
#endif
/**