Merge branch 'upstream/ticketlock-cleanup' of git://github.com/jsgf/linux-xen into...

[pandora-kernel.git] / drivers / pci / probe.c

diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 8473727..f3f94a5 100644 (file)
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -1351,7 +1351,8 @@ static int pcie_find_smpss(struct pci_dev *dev, void *data)
         * will occur as normal.
         */
        if (dev->is_hotplug_bridge && (!list_is_singular(&dev->bus->devices) ||
-           dev->bus->self->pcie_type != PCI_EXP_TYPE_ROOT_PORT))
+            (dev->bus->self &&
+             dev->bus->self->pcie_type != PCI_EXP_TYPE_ROOT_PORT)))
                *smpss = 0;
 
        if (*smpss > dev->pcie_mpss)
@@ -1396,34 +1397,37 @@ static void pcie_write_mps(struct pci_dev *dev, int mps)
 
 static void pcie_write_mrrs(struct pci_dev *dev, int mps)
 {
-       int rc, mrrs;
+       int rc, mrrs, dev_mpss;
 
-       if (pcie_bus_config == PCIE_BUS_PERFORMANCE) {
-               int dev_mpss = 128 << dev->pcie_mpss;
+       /* In the "safe" case, do not configure the MRRS.  There appear to be
+        * issues with setting MRRS to 0 on a number of devices.
+        */
 
-               /* For Max performance, the MRRS must be set to the largest
-                * supported value.  However, it cannot be configured larger
-                * than the MPS the device or the bus can support.  This assumes
-                * that the largest MRRS available on the device cannot be
-                * smaller than the device MPSS.
-                */
-               mrrs = mps < dev_mpss ? mps : dev_mpss;
-       } else
-               /* In the "safe" case, configure the MRRS for fairness on the
-                * bus by making all devices have the same size
-                */
-               mrrs = mps;
+       if (pcie_bus_config != PCIE_BUS_PERFORMANCE)
+               return;
 
+       dev_mpss = 128 << dev->pcie_mpss;
+
+       /* For Max performance, the MRRS must be set to the largest supported
+        * value.  However, it cannot be configured larger than the MPS the
+        * device or the bus can support.  This assumes that the largest MRRS
+        * available on the device cannot be smaller than the device MPSS.
+        */
+       mrrs = min(mps, dev_mpss);
 
        /* MRRS is a R/W register.  Invalid values can be written, but a
-        * subsiquent read will verify if the value is acceptable or not.
+        * subsequent read will verify if the value is acceptable or not.
         * If the MRRS value provided is not acceptable (e.g., too large),
         * shrink the value until it is acceptable to the HW.
         */
        while (mrrs != pcie_get_readrq(dev) && mrrs >= 128) {
+               dev_warn(&dev->dev, "Attempting to modify the PCI-E MRRS value"
+                        " to %d.  If any issues are encountered, please try "
+                        "running with pci=pcie_bus_safe\n", mrrs);
                rc = pcie_set_readrq(dev, mrrs);
                if (rc)
-                       dev_err(&dev->dev, "Failed attempting to set the MRRS\n");
+                       dev_err(&dev->dev,
+                               "Failed attempting to set the MRRS\n");
 
                mrrs /= 2;
        }
@@ -1436,13 +1440,13 @@ static int pcie_bus_configure_set(struct pci_dev *dev, void *data)
        if (!pci_is_pcie(dev))
                return 0;
 
-       dev_info(&dev->dev, "Dev MPS %d MPSS %d MRRS %d\n",
+       dev_dbg(&dev->dev, "Dev MPS %d MPSS %d MRRS %d\n",
                 pcie_get_mps(dev), 128<<dev->pcie_mpss, pcie_get_readrq(dev));
 
        pcie_write_mps(dev, mps);
        pcie_write_mrrs(dev, mps);
 
-       dev_info(&dev->dev, "Dev MPS %d MPSS %d MRRS %d\n",
+       dev_dbg(&dev->dev, "Dev MPS %d MPSS %d MRRS %d\n",
                 pcie_get_mps(dev), 128<<dev->pcie_mpss, pcie_get_readrq(dev));
 
        return 0;
@@ -1456,9 +1460,6 @@ void pcie_bus_configure_settings(struct pci_bus *bus, u8 mpss)
 {
        u8 smpss = mpss;
 
-       if (!bus->self)
-               return;
-
        if (!pci_is_pcie(bus->self))
                return;