netxen: fix coherent dma mask setting

Change default dma mask for NX3031 to 39 bit with ability
to update it to 64-bit (if firmware indicates support). Old
code was restricting it under 4GB (32-bit), sometimes causing
failure to allocate descriptor rings on heavily populated
system. NX2031 based NICs will still get 32-bit coherent mask.

Signed-off-by: Dhananjay Phadke <dhananjay@netxen.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 25 insertions, 12 deletions

diff --git a/drivers/net/netxen/netxen_nic_main.c b/drivers/net/netxen/netxen_nic_main.c
index 637ac8b89bac..3cd8cfcf627b 100644
--- a/drivers/net/netxen/netxen_nic_main.c
+++ b/drivers/net/netxen/netxen_nic_main.c
@@ -221,7 +221,7 @@ netxen_napi_disable(struct netxen_adapter *adapter)
         }
 }
 
-static int nx_set_dma_mask(struct netxen_adapter *adapter, uint8_t revision_id)
+static int nx_set_dma_mask(struct netxen_adapter *adapter)
 {
         struct pci_dev *pdev = adapter->pdev;
         uint64_t mask, cmask;
@@ -229,19 +229,17 @@ static int nx_set_dma_mask(struct netxen_adapter *adapter, uint8_t revision_id)
         adapter->pci_using_dac = 0;
 
         mask = DMA_BIT_MASK(32);
-        /*
-         * Consistent DMA mask is set to 32 bit because it cannot be set to
-         * 35 bits. For P3 also leave it at 32 bits for now. Only the rings
-         * come off this pool.
-         */
         cmask = DMA_BIT_MASK(32);
 
+        if (NX_IS_REVISION_P2(adapter->ahw.revision_id)) {
 #ifndef CONFIG_IA64
-        if (revision_id >= NX_P3_B0)
-                mask = DMA_BIT_MASK(39);
-        else if (revision_id == NX_P2_C1)
                 mask = DMA_BIT_MASK(35);
 #endif
+        } else {
+                mask = DMA_BIT_MASK(39);
+                cmask = mask;
+        }
+
         if (pci_set_dma_mask(pdev, mask) == 0 &&
                 pci_set_consistent_dma_mask(pdev, cmask) == 0) {
                 adapter->pci_using_dac = 1;
@@ -256,7 +254,7 @@ static int
 nx_update_dma_mask(struct netxen_adapter *adapter)
 {
         int change, shift, err;
-        uint64_t mask, old_mask;
+        uint64_t mask, old_mask, old_cmask;
         struct pci_dev *pdev = adapter->pdev;
 
         change = 0;
@@ -272,14 +270,29 @@ nx_update_dma_mask(struct netxen_adapter *adapter)
 
         if (change) {
                 old_mask = pdev->dma_mask;
+                old_cmask = pdev->dev.coherent_dma_mask;
+
                 mask = (1ULL<<(32+shift)) - 1;
 
                 err = pci_set_dma_mask(pdev, mask);
                 if (err)
-                        return pci_set_dma_mask(pdev, old_mask);
+                        goto err_out;
+
+                if (NX_IS_REVISION_P3(adapter->ahw.revision_id)) {
+
+                        err = pci_set_consistent_dma_mask(pdev, mask);
+                        if (err)
+                                goto err_out;
+                }
+                dev_info(&pdev->dev, "using %d-bit dma mask\n", 32+shift);
         }
 
         return 0;
+
+err_out:
+        pci_set_dma_mask(pdev, old_mask);
+        pci_set_consistent_dma_mask(pdev, old_cmask);
+        return err;
 }
 
 static void netxen_check_options(struct netxen_adapter *adapter)
@@ -1006,7 +1019,7 @@ netxen_nic_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
         revision_id = pdev->revision;
         adapter->ahw.revision_id = revision_id;
 
-        err = nx_set_dma_mask(adapter, revision_id);
+        err = nx_set_dma_mask(adapter);
         if (err)
                 goto err_out_free_netdev;