P4 to Git Change 1138096 by skudchad@skudchad_test_win_opencl2 on 2015/04/07 13:46:20

EPR #403782 - IOMMU2/SVM
	- Handle case of only one DMA engine available, for example with SVM.

	ReviewBoardURL = http://ocltc.amd.com/reviews/r/7284/diff/

Affected files ...

... //depot/stg/opencl/drivers/opencl/runtime/device/gpu/gpudevice.cpp#506 edit
... //depot/stg/opencl/drivers/opencl/runtime/device/gpu/gpudevice.hpp#142 edit
... //depot/stg/opencl/drivers/opencl/runtime/device/gpu/gpuvirtual.cpp#357 edit

rocclr/runtime/device/gpu/gpudevice.cpp

@@ -245,6 +245,7 @@ void
 Device::Engines::create(uint num, gslEngineDescriptor* desc, uint maxNumComputeRings)
 {
     numComputeRings_ = 0;
+    numDmaEngines_ = 0;
 
     for (uint i = 0; i < num; ++i) {
         desc_[desc[i].id] = desc[i];
@@ -254,6 +255,11 @@ Device::Engines::create(uint num, gslEngineDescriptor* desc, uint maxNumComputeR
             desc[i].id <= GSL_ENGINEID_COMPUTE7) {
             numComputeRings_++;
         }
+
+        if (desc[i].id >= GSL_ENGINEID_DRMDMA0 &&
+            desc[i].id <= GSL_ENGINEID_DRMDMA1) {
+            numDmaEngines_++;
+        }
     }
 
     numComputeRings_ = std::min(numComputeRings_, maxNumComputeRings);

rocclr/runtime/device/gpu/gpudevice.hpp

@@ -218,8 +218,12 @@ public:
         //! Returns the number of available compute rings
         uint numComputeRings() const { return numComputeRings_; }
 
+        //! Returns the number of available DMA engines
+        uint numDMAEngines() const { return numDmaEngines_; }
+
     private:
         uint numComputeRings_;
+        uint numDmaEngines_;
         gslEngineDescriptor desc_[GSL_ENGINEID_MAX];    //!< Engine descriptor
     };
 

rocclr/runtime/device/gpu/gpuvirtual.cpp

@@ -498,7 +498,11 @@ VirtualGPU::create(
             engineMask = dev().engines().getMask((gslEngineID)(dev().isComputeRingIDForced() ?
                          dev().getforcedComputeEngineID() : (GSL_ENGINEID_COMPUTE0 + idx)));
             if (dev().canDMA()) {
-                if (index() & 0x1) {
+                // If only 1 DMA engine is available then use that one
+                if (dev().engines().numDMAEngines() < 2) {
+                    engineMask |= dev().engines().getMask(GSL_ENGINEID_DRMDMA0);
+                }
+                else if (index() & 0x1) {
                     engineMask |= dev().engines().getMask(GSL_ENGINEID_DRMDMA0);
                 }
                 else {