4 files changed, 51 insertions, 19 deletions

diff --git a/drivers/pci/host/pci-mvebu.c b/drivers/pci/host/pci-mvebu.c
index 1dd759596b0a..1309cfbaa719 100644
--- a/drivers/pci/host/pci-mvebu.c
+++ b/drivers/pci/host/pci-mvebu.c
@@ -101,9 +101,7 @@ struct mvebu_pcie {
         struct mvebu_pcie_port *ports;
         struct msi_controller *msi;
         struct resource io;
-        char io_name[30];
         struct resource realio;
-        char mem_name[30];
         struct resource mem;
         struct resource busn;
         int nports;
@@ -723,18 +721,9 @@ static int mvebu_pcie_setup(int nr, struct pci_sys_data *sys)
 {
         struct mvebu_pcie *pcie = sys_to_pcie(sys);
         int i;
-        int domain = 0;
 
-#ifdef CONFIG_PCI_DOMAINS
-        domain = sys->domain;
-#endif
-
-        snprintf(pcie->mem_name, sizeof(pcie->mem_name), "PCI MEM %04x",
-                 domain);
-        pcie->mem.name = pcie->mem_name;
-
-        snprintf(pcie->io_name, sizeof(pcie->io_name), "PCI I/O %04x", domain);
-        pcie->realio.name = pcie->io_name;
+        pcie->mem.name = "PCI MEM";
+        pcie->realio.name = "PCI I/O";
 
         if (request_resource(&iomem_resource, &pcie->mem))
                 return 0;
diff --git a/drivers/pci/host/pcie-designware.c b/drivers/pci/host/pcie-designware.c
index df781cdf13c1..eef311115899 100644
--- a/drivers/pci/host/pcie-designware.c
+++ b/drivers/pci/host/pcie-designware.c
@@ -508,9 +508,6 @@ int __init dw_pcie_host_init(struct pcie_port *pp)
         dw_pci.private_data = (void **)&pp;
 
         pci_common_init_dev(pp->dev, &dw_pci);
-#ifdef CONFIG_PCI_DOMAINS
-        dw_pci.domain++;
-#endif
 
         return 0;
 }
diff --git a/drivers/pci/host/pcie-rcar.c b/drivers/pci/host/pcie-rcar.c
index 748786c402fc..ba28078b70e3 100644
--- a/drivers/pci/host/pcie-rcar.c
+++ b/drivers/pci/host/pcie-rcar.c
@@ -397,9 +397,6 @@ static void rcar_pcie_enable(struct rcar_pcie *pcie)
 #endif
 
         pci_common_init_dev(&pdev->dev, &rcar_pci);
-#ifdef CONFIG_PCI_DOMAINS
-        rcar_pci.domain++;
-#endif
 }
 
 static int phy_wait_for_ack(struct rcar_pcie *pcie)
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index cab05f31223f..c419554d0b4b 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -10,6 +10,8 @@
 #include <linux/kernel.h>
 #include <linux/delay.h>
 #include <linux/init.h>
+#include <linux/of.h>
+#include <linux/of_pci.h>
 #include <linux/pci.h>
 #include <linux/pm.h>
 #include <linux/slab.h>
@@ -4439,6 +4441,53 @@ int pci_get_new_domain_nr(void)
 {
         return atomic_inc_return(&__domain_nr);
 }
+
+#ifdef CONFIG_PCI_DOMAINS_GENERIC
+void pci_bus_assign_domain_nr(struct pci_bus *bus, struct device *parent)
+{
+        static int use_dt_domains = -1;
+        int domain = of_get_pci_domain_nr(parent->of_node);
+
+        /*
+         * 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 >= 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 {
+                dev_err(parent, "Node %s has inconsistent \"linux,pci-domain\" property in DT\n",
+                        parent->of_node->full_name);
+                domain = -1;
+        }
+
+        bus->domain_nr = domain;
+}
+#endif
 #endif
 
 /**