IB/mthca: Use PCI-X/PCI-Express read control interfaces

These driver changes incorporate the proposed PCI-X / PCI-Express read
byte count interface.  Reading and setting those values doesn't take
place "manually", instead wrapping functions are called to allow
quirks for some PCI bridges.

Signed-off by: Peter Oruba <peter.oruba@amd.com>
Based on work by Stephen Hemminger <shemminger@linux-foundation.org>
Cc: Roland Dreier <rolandd@cisco.com>
Cc: Michael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

1 files changed, 8 insertions, 25 deletions

diff --git a/drivers/infiniband/hw/mthca/mthca_main.c b/drivers/infiniband/hw/mthca/mthca_main.c
index 04c1520524cd..60de6f93869e 100644
--- a/drivers/infiniband/hw/mthca/mthca_main.c
+++ b/drivers/infiniband/hw/mthca/mthca_main.c
@@ -137,40 +137,23 @@ static const char mthca_version[] __devinitdata =
 
 static int mthca_tune_pci(struct mthca_dev *mdev)
 {
-        int cap;
-        u16 val;
-
         if (!tune_pci)
                 return 0;
 
         /* First try to max out Read Byte Count */
-        cap = pci_find_capability(mdev->pdev, PCI_CAP_ID_PCIX);
-        if (cap) {
-                if (pci_read_config_word(mdev->pdev, cap + PCI_X_CMD, &val)) {
-                        mthca_err(mdev, "Couldn't read PCI-X command register, "
-                                  "aborting.\n");
-                        return -ENODEV;
-                }
-                val = (val & ~PCI_X_CMD_MAX_READ) | (3 << 2);
-                if (pci_write_config_word(mdev->pdev, cap + PCI_X_CMD, val)) {
-                        mthca_err(mdev, "Couldn't write PCI-X command register, "
-                                  "aborting.\n");
+        if (pci_find_capability(mdev->pdev, PCI_CAP_ID_PCIX)) {
+                if (pcix_set_mmrbc(mdev->pdev, pcix_get_max_mmrbc(mdev->pdev))) {
+                        mthca_err(mdev, "Couldn't set PCI-X max read count, "
+                                "aborting.\n");
                         return -ENODEV;
                 }
         } else if (!(mdev->mthca_flags & MTHCA_FLAG_PCIE))
                 mthca_info(mdev, "No PCI-X capability, not setting RBC.\n");
 
-        cap = pci_find_capability(mdev->pdev, PCI_CAP_ID_EXP);
-        if (cap) {
-                if (pci_read_config_word(mdev->pdev, cap + PCI_EXP_DEVCTL, &val)) {
-                        mthca_err(mdev, "Couldn't read PCI Express device control "
-                                  "register, aborting.\n");
-                        return -ENODEV;
-                }
-                val = (val & ~PCI_EXP_DEVCTL_READRQ) | (5 << 12);
-                if (pci_write_config_word(mdev->pdev, cap + PCI_EXP_DEVCTL, val)) {
-                        mthca_err(mdev, "Couldn't write PCI Express device control "
-                                  "register, aborting.\n");
+        if (pci_find_capability(mdev->pdev, PCI_CAP_ID_EXP)) {
+                if (pcie_set_readrq(mdev->pdev, 4096)) {
+                        mthca_err(mdev, "Couldn't write PCI Express read request, "
+                                "aborting.\n");
                         return -ENODEV;
                 }
         } else if (mdev->mthca_flags & MTHCA_FLAG_PCIE)