x86/PCI: prepare pci_mmcfg_check_reserved() to be called at runtime

Prepare function pci_mmcfg_check_reserved() to be called at runtime
for PCI host bridge hot-plugging

Reviewed-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Jiang Liu <liuj97@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

1 files changed, 68 insertions, 36 deletions

diff --git a/arch/x86/pci/mmconfig-shared.c b/arch/x86/pci/mmconfig-shared.c
index 0ac97d54bcac..15a7abf5139c 100644
--- a/arch/x86/pci/mmconfig-shared.c
+++ b/arch/x86/pci/mmconfig-shared.c
@@ -27,6 +27,7 @@
 
 /* Indicate if the mmcfg resources have been placed into the resource table. */
 static int __initdata pci_mmcfg_resources_inserted;
+static bool pci_mmcfg_running_state;
 static DEFINE_MUTEX(pci_mmcfg_lock);
 
 LIST_HEAD(pci_mmcfg_list);
@@ -375,14 +376,15 @@ static void __init pci_mmcfg_insert_resources(void)
         struct pci_mmcfg_region *cfg;
 
         list_for_each_entry(cfg, &pci_mmcfg_list, list)
-                insert_resource(&iomem_resource, &cfg->res);
+                if (!cfg->res.parent)
+                        insert_resource(&iomem_resource, &cfg->res);
 
         /* Mark that the resources have been inserted. */
         pci_mmcfg_resources_inserted = 1;
 }
 
-static acpi_status __init check_mcfg_resource(struct acpi_resource *res,
-                                              void *data)
+static acpi_status __devinit check_mcfg_resource(struct acpi_resource *res,
+                                                 void *data)
 {
         struct resource *mcfg_res = data;
         struct acpi_resource_address64 address;
@@ -418,8 +420,8 @@ static acpi_status __init check_mcfg_resource(struct acpi_resource *res,
         return AE_OK;
 }
 
-static acpi_status __init find_mboard_resource(acpi_handle handle, u32 lvl,
-                void *context, void **rv)
+static acpi_status __devinit find_mboard_resource(acpi_handle handle, u32 lvl,
+                                                  void *context, void **rv)
 {
         struct resource *mcfg_res = context;
 
@@ -432,7 +434,7 @@ static acpi_status __init find_mboard_resource(acpi_handle handle, u32 lvl,
         return AE_OK;
 }
 
-static int __init is_acpi_reserved(u64 start, u64 end, unsigned not_used)
+static int __devinit is_acpi_reserved(u64 start, u64 end, unsigned not_used)
 {
         struct resource mcfg_res;
 
@@ -451,13 +453,15 @@ static int __init is_acpi_reserved(u64 start, u64 end, unsigned not_used)
 
 typedef int (*check_reserved_t)(u64 start, u64 end, unsigned type);
 
-static int __init is_mmconf_reserved(check_reserved_t is_reserved,
-                                    struct pci_mmcfg_region *cfg, int with_e820)
+static int __ref is_mmconf_reserved(check_reserved_t is_reserved,
+                                    struct pci_mmcfg_region *cfg,
+                                    struct device *dev, int with_e820)
 {
         u64 addr = cfg->res.start;
         u64 size = resource_size(&cfg->res);
         u64 old_size = size;
-        int valid = 0, num_buses;
+        int num_buses;
+        char *method = with_e820 ? "E820" : "ACPI motherboard resources";
 
         while (!is_reserved(addr, addr + size, E820_RESERVED)) {
                 size >>= 1;
@@ -465,49 +469,75 @@ static int __init is_mmconf_reserved(check_reserved_t is_reserved,
                         break;
         }
 
-        if (size >= (16UL<<20) || size == old_size) {
-                printk(KERN_INFO PREFIX "MMCONFIG at %pR reserved in %s\n",
-                       &cfg->res,
-                       with_e820 ? "E820" : "ACPI motherboard resources");
-                valid = 1;
-
-                if (old_size != size) {
-                        /* update end_bus */
-                        cfg->end_bus = cfg->start_bus + ((size>>20) - 1);
-                        num_buses = cfg->end_bus - cfg->start_bus + 1;
-                        cfg->res.end = cfg->res.start +
-                            PCI_MMCFG_BUS_OFFSET(num_buses) - 1;
-                        snprintf(cfg->name, PCI_MMCFG_RESOURCE_NAME_LEN,
-                                 "PCI MMCONFIG %04x [bus %02x-%02x]",
-                                 cfg->segment, cfg->start_bus, cfg->end_bus);
+        if (size < (16UL<<20) && size != old_size)
+                return 0;
+
+        if (dev)
+                dev_info(dev, "MMCONFIG at %pR reserved in %s\n",
+                         &cfg->res, method);
+        else
+                printk(KERN_INFO PREFIX
+                       "MMCONFIG at %pR reserved in %s\n",
+                       &cfg->res, method);
+
+        if (old_size != size) {
+                /* update end_bus */
+                cfg->end_bus = cfg->start_bus + ((size>>20) - 1);
+                num_buses = cfg->end_bus - cfg->start_bus + 1;
+                cfg->res.end = cfg->res.start +
+                    PCI_MMCFG_BUS_OFFSET(num_buses) - 1;
+                snprintf(cfg->name, PCI_MMCFG_RESOURCE_NAME_LEN,
+                         "PCI MMCONFIG %04x [bus %02x-%02x]",
+                         cfg->segment, cfg->start_bus, cfg->end_bus);
+
+                if (dev)
+                        dev_info(dev,
+                                "MMCONFIG "
+                                "at %pR (base %#lx) (size reduced!)\n",
+                                &cfg->res, (unsigned long) cfg->address);
+                else
                         printk(KERN_INFO PREFIX
-                               "MMCONFIG for %04x [bus%02x-%02x] "
-                               "at %pR (base %#lx) (size reduced!)\n",
-                               cfg->segment, cfg->start_bus, cfg->end_bus,
-                               &cfg->res, (unsigned long) cfg->address);
-                }
+                                "MMCONFIG for %04x [bus%02x-%02x] "
+                                "at %pR (base %#lx) (size reduced!)\n",
+                                cfg->segment, cfg->start_bus, cfg->end_bus,
+                                &cfg->res, (unsigned long) cfg->address);
         }
 
-        return valid;
+        return 1;
 }
 
-static int __devinit pci_mmcfg_check_reserved(struct pci_mmcfg_region *cfg,
-                                              int early)
+static int __ref pci_mmcfg_check_reserved(struct device *dev,
+                  struct pci_mmcfg_region *cfg, int early)
 {
         if (!early && !acpi_disabled) {
-                if (is_mmconf_reserved(is_acpi_reserved, cfg, 0))
+                if (is_mmconf_reserved(is_acpi_reserved, cfg, dev, 0))
                         return 1;
+
+                if (dev)
+                        dev_info(dev, FW_INFO
+                                 "MMCONFIG at %pR not reserved in "
+                                 "ACPI motherboard resources\n",
+                                 &cfg->res);
                 else
-                        printk(KERN_ERR FW_BUG PREFIX
+                        printk(KERN_INFO FW_INFO PREFIX
                                "MMCONFIG at %pR not reserved in "
                                "ACPI motherboard resources\n",
                                &cfg->res);
         }
 
+        /*
+         * e820_all_mapped() is marked as __init.
+         * All entries from ACPI MCFG table have been checked at boot time.
+         * For MCFG information constructed from hotpluggable host bridge's
+         * _CBA method, just assume it's reserved.
+         */
+        if (pci_mmcfg_running_state)
+                return 1;
+
         /* Don't try to do this check unless configuration
            type 1 is available. how about type 2 ?*/
         if (raw_pci_ops)
-                return is_mmconf_reserved(e820_all_mapped, cfg, 1);
+                return is_mmconf_reserved(e820_all_mapped, cfg, dev, 1);
 
         return 0;
 }
@@ -517,7 +547,7 @@ static void __init pci_mmcfg_reject_broken(int early)
         struct pci_mmcfg_region *cfg;
 
         list_for_each_entry(cfg, &pci_mmcfg_list, list) {
-                if (pci_mmcfg_check_reserved(cfg, early) == 0) {
+                if (pci_mmcfg_check_reserved(NULL, cfg, early) == 0) {
                         printk(KERN_INFO PREFIX "not using MMCONFIG\n");
                         free_all_mmcfg();
                         return;
@@ -656,6 +686,8 @@ void __init pci_mmcfg_late_init(void)
 
 static int __init pci_mmcfg_late_insert_resources(void)
 {
+        pci_mmcfg_running_state = true;
+
         /*
          * If resources are already inserted or we are not using MMCONFIG,
          * don't insert the resources.