# HG changeset patch
# Parent 0f12e80e810de1a9927db1f25dbea49acd73ae3c
e1000: start a DMA allocation/mapping abstraction

It currently matches a lot the Linux DMA API but it should be usable by
other OSes too. The Linux DMA API is described at the end of the chapter
15 in the LDD3.

This will be useful to remove Linux specific DMA code from
e1000::set_up_device which should be only device independent code.


diff --git a/rathaxes/samples/e1000/dma.rti b/rathaxes/samples/e1000/dma.rti
new file mode 100644
--- /dev/null
+++ b/rathaxes/samples/e1000/dma.rti
@@ -0,0 +1,34 @@
+interface DMA : Builtin, LKM, Device
+{
+    provided type   AbstractDMAHandle
+    {
+        chunk       LKM::includes();
+        decl        data_types();
+        attribute   Builtin::symbol.scalar  k_dma_handle;
+    }
+
+    provided type   Direction
+    {
+        decl    data_types();
+    }
+
+    provided sequence   map(Device::AbstractDevice, Builtin::symbol, Builtin::number, Direction)
+    {
+        provided chunk  ::CALL(); /* -> AbstractDMAHandle */
+    }
+
+    provided sequence   unmap(Device::AbstractDevice, AbstractDMAHandle, Builtin::number, Direction)
+    {
+        provided chunk  ::CALL();
+    }
+
+    provided sequence   alloc_coherent(Device::AbstractDevice, Builtin::number, Builtin::symbol)
+    {
+        provided chunk  ::CALL(); /* -> AbstractDMAHandle + addr returned via the symbol */
+    }
+
+    provided sequence   free_coherent(Device::AbstractDevice, Builtin::number, Builtin::symbol, AbstractDMAHandle)
+    {
+        provided chunk  ::CALL();
+    }
+}