1 files changed, 93 insertions, 28 deletions

diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index e6a917b4acd3..ff94b69738a8 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -1745,21 +1745,50 @@ static void program_hpp_type2(struct pci_dev *dev, struct hpp_type2 *hpp)
          */
 }
 
-static void pci_configure_extended_tags(struct pci_dev *dev)
+int pci_configure_extended_tags(struct pci_dev *dev, void *ign)
 {
-        u32 dev_cap;
+        struct pci_host_bridge *host;
+        u32 cap;
+        u16 ctl;
         int ret;
 
         if (!pci_is_pcie(dev))
-                return;
+                return 0;
 
-        ret = pcie_capability_read_dword(dev, PCI_EXP_DEVCAP, &dev_cap);
+        ret = pcie_capability_read_dword(dev, PCI_EXP_DEVCAP, &cap);
         if (ret)
-                return;
+                return 0;
+
+        if (!(cap & PCI_EXP_DEVCAP_EXT_TAG))
+                return 0;
+
+        ret = pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &ctl);
+        if (ret)
+                return 0;
+
+        host = pci_find_host_bridge(dev->bus);
+        if (!host)
+                return 0;
 
-        if (dev_cap & PCI_EXP_DEVCAP_EXT_TAG)
+        /*
+         * If some device in the hierarchy doesn't handle Extended Tags
+         * correctly, make sure they're disabled.
+         */
+        if (host->no_ext_tags) {
+                if (ctl & PCI_EXP_DEVCTL_EXT_TAG) {
+                        dev_info(&dev->dev, "disabling Extended Tags\n");
+                        pcie_capability_clear_word(dev, PCI_EXP_DEVCTL,
+                                                   PCI_EXP_DEVCTL_EXT_TAG);
+                }
+                return 0;
+        }
+
+        if (!(ctl & PCI_EXP_DEVCTL_EXT_TAG)) {
+                dev_info(&dev->dev, "enabling Extended Tags\n");
                 pcie_capability_set_word(dev, PCI_EXP_DEVCTL,
                                          PCI_EXP_DEVCTL_EXT_TAG);
+        }
+        return 0;
 }
 
 /**
@@ -1810,7 +1839,7 @@ static void pci_configure_device(struct pci_dev *dev)
         int ret;
 
         pci_configure_mps(dev);
-        pci_configure_extended_tags(dev);
+        pci_configure_extended_tags(dev, NULL);
         pci_configure_relaxed_ordering(dev);
 
         memset(&hpp, 0, sizeof(hpp));
@@ -1867,42 +1896,69 @@ struct pci_dev *pci_alloc_dev(struct pci_bus *bus)
 }
 EXPORT_SYMBOL(pci_alloc_dev);
 
-bool pci_bus_read_dev_vendor_id(struct pci_bus *bus, int devfn, u32 *l,
-                                int crs_timeout)
+static bool pci_bus_crs_vendor_id(u32 l)
+{
+        return (l & 0xffff) == 0x0001;
+}
+
+static bool pci_bus_wait_crs(struct pci_bus *bus, int devfn, u32 *l,
+                             int timeout)
 {
         int delay = 1;
 
-        if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l))
-                return false;
+        if (!pci_bus_crs_vendor_id(*l))
+                return true;    /* not a CRS completion */
 
-        /* some broken boards return 0 or ~0 if a slot is empty: */
-        if (*l == 0xffffffff || *l == 0x00000000 ||
-            *l == 0x0000ffff || *l == 0xffff0000)
-                return false;
+        if (!timeout)
+                return false;   /* CRS, but caller doesn't want to wait */
 
         /*
-         * Configuration Request Retry Status.  Some root ports return the
-         * actual device ID instead of the synthetic ID (0xFFFF) required
-         * by the PCIe spec.  Ignore the device ID and only check for
-         * (vendor id == 1).
+         * We got the reserved Vendor ID that indicates a completion with
+         * Configuration Request Retry Status (CRS).  Retry until we get a
+         * valid Vendor ID or we time out.
          */
-        while ((*l & 0xffff) == 0x0001) {
-                if (!crs_timeout)
+        while (pci_bus_crs_vendor_id(*l)) {
+                if (delay > timeout) {
+                        pr_warn("pci %04x:%02x:%02x.%d: not ready after %dms; giving up\n",
+                                pci_domain_nr(bus), bus->number,
+                                PCI_SLOT(devfn), PCI_FUNC(devfn), delay - 1);
+
                         return false;
+                }
+                if (delay >= 1000)
+                        pr_info("pci %04x:%02x:%02x.%d: not ready after %dms; waiting\n",
+                                pci_domain_nr(bus), bus->number,
+                                PCI_SLOT(devfn), PCI_FUNC(devfn), delay - 1);
 
                 msleep(delay);
                 delay *= 2;
+
                 if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l))
                         return false;
-                /* Card hasn't responded in 60 seconds?  Must be stuck. */
-                if (delay > crs_timeout) {
-                        printk(KERN_WARNING "pci %04x:%02x:%02x.%d: not responding\n",
-                               pci_domain_nr(bus), bus->number, PCI_SLOT(devfn),
-                               PCI_FUNC(devfn));
-                        return false;
-                }
         }
 
+        if (delay >= 1000)
+                pr_info("pci %04x:%02x:%02x.%d: ready after %dms\n",
+                        pci_domain_nr(bus), bus->number,
+                        PCI_SLOT(devfn), PCI_FUNC(devfn), delay - 1);
+
+        return true;
+}
+
+bool pci_bus_read_dev_vendor_id(struct pci_bus *bus, int devfn, u32 *l,
+                                int timeout)
+{
+        if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l))
+                return false;
+
+        /* some broken boards return 0 or ~0 if a slot is empty: */
+        if (*l == 0xffffffff || *l == 0x00000000 ||
+            *l == 0x0000ffff || *l == 0xffff0000)
+                return false;
+
+        if (pci_bus_crs_vendor_id(*l))
+                return pci_bus_wait_crs(bus, devfn, l, timeout);
+
         return true;
 }
 EXPORT_SYMBOL(pci_bus_read_dev_vendor_id);
@@ -2331,6 +2387,15 @@ void pcie_bus_configure_settings(struct pci_bus *bus)
 }
 EXPORT_SYMBOL_GPL(pcie_bus_configure_settings);
 
+/*
+ * Called after each bus is probed, but before its children are examined.  This
+ * is marked as __weak because multiple architectures define it.
+ */
+void __weak pcibios_fixup_bus(struct pci_bus *bus)
+{
+       /* nothing to do, expected to be removed in the future */
+}
+
 unsigned int pci_scan_child_bus(struct pci_bus *bus)
 {
         unsigned int devfn, pass, max = bus->busn_res.start;