I/OAT: Add support for version 2 of ioatdma device

Add support for version 2 of the ioatdma device.  This device handles
the descriptor chain and DCA services slightly differently:
 - Instead of moving the dma descriptors between a busy and an idle chain,
   this new version uses a single circular chain so that we don't have
   rewrite the next_descriptor pointers as we add new requests, and the
   device doesn't need to re-read the last descriptor.
 - The new device has the DCA tags defined internally instead of needing
   them defined statically.

Signed-off-by: Shannon Nelson <shannon.nelson@intel.com>
Cc: "Williams, Dan J" <dan.j.williams@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 11 insertions, 0 deletions

diff --git a/drivers/dma/ioat.c b/drivers/dma/ioat.c
index f204c39fb412..16e0fd8facfb 100644
--- a/drivers/dma/ioat.c
+++ b/drivers/dma/ioat.c
@@ -39,10 +39,14 @@ MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Intel Corporation");
 
 static struct pci_device_id ioat_pci_tbl[] = {
+        /* I/OAT v1 platforms */
         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT) },
         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT_CNB)  },
         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT_SCNB) },
         { PCI_DEVICE(PCI_VENDOR_ID_UNISYS, PCI_DEVICE_ID_UNISYS_DMA_DIRECTOR) },
+
+        /* I/OAT v2 platforms */
+        { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT_SNB) },
         { 0, }
 };
 
@@ -74,10 +78,17 @@ static int ioat_setup_functionality(struct pci_dev *pdev, void __iomem *iobase)
                 if (device->dma && ioat_dca_enabled)
                         device->dca = ioat_dca_init(pdev, iobase);
                 break;
+        case IOAT_VER_2_0:
+                device->dma = ioat_dma_probe(pdev, iobase);
+                if (device->dma && ioat_dca_enabled)
+                        device->dca = ioat2_dca_init(pdev, iobase);
+                break;
         default:
                 err = -ENODEV;
                 break;
         }
+        if (!device->dma)
+                err = -ENODEV;
         return err;
 }