patch-2.4.10 linux/arch/mips64/sgi-ip27/ip27-pci-dma.c

• Lines: 122
• Date: Sun Sep 9 10:43:02 2001
• Orig file: v2.4.9/linux/arch/mips64/sgi-ip27/ip27-pci-dma.c
• Orig date: Tue Nov 28 21:42:04 2000

diff -u --recursive --new-file v2.4.9/linux/arch/mips64/sgi-ip27/ip27-pci-dma.c linux/arch/mips64/sgi-ip27/ip27-pci-dma.c
@@ -1,5 +1,4 @@
-/* $Id: ip27-pci-dma.c,v 1.1 2000/02/16 21:22:00 ralf Exp $
- *
+/*
  * Dynamic DMA mapping support.
  *
  * On the Origin there is dynamic DMA address translation for all PCI DMA.
@@ -52,4 +51,114 @@
 			 void *vaddr, dma_addr_t dma_handle)
 {
 	free_pages((unsigned long)vaddr, __get_order(size));
+}
+
+/*
+ * Map a single buffer of the indicated size for DMA in streaming mode.
+ * The 32-bit bus address to use is returned.
+ *
+ * Once the device is given the dma address, the device owns this memory
+ * until either pci_unmap_single or pci_dma_sync_single is performed.
+ */
+dma_addr_t pci_map_single(struct pci_dev *hwdev, void *ptr, size_t size,
+                          int direction)
+{
+	if (direction == PCI_DMA_NONE)
+		BUG();
+
+	return (bus_to_baddr[hwdev->bus->number] | __pa(ptr));
+}
+
+/*
+ * Unmap a single streaming mode DMA translation.  The dma_addr and size
+ * must match what was provided for in a previous pci_map_single call.  All
+ * other usages are undefined.
+ *
+ * After this call, reads by the cpu to the buffer are guarenteed to see
+ * whatever the device wrote there.
+ */
+void pci_unmap_single(struct pci_dev *hwdev, dma_addr_t dma_addr,
+                     size_t size, int direction)
+{
+	if (direction == PCI_DMA_NONE)
+		BUG();
+
+	/* Nothing to do */
+}
+
+/*
+ * Map a set of buffers described by scatterlist in streaming
+ * mode for DMA.  This is the scather-gather version of the
+ * above pci_map_single interface.  Here the scatter gather list
+ * elements are each tagged with the appropriate dma address
+ * and length.  They are obtained via sg_dma_{address,length}(SG).
+ *
+ * NOTE: An implementation may be able to use a smaller number of
+ *       DMA address/length pairs than there are SG table elements.
+ *       (for example via virtual mapping capabilities)
+ *       The routine returns the number of addr/length pairs actually
+ *       used, at most nents.
+ *
+ * Device ownership issues as mentioned above for pci_map_single are
+ * the same here.
+ */
+int pci_map_sg(struct pci_dev *hwdev, struct scatterlist *sg, int nents,
+               int direction)
+{
+	int i;
+
+	if (direction == PCI_DMA_NONE)
+		BUG();
+
+	/* Make sure that gcc doesn't leave the empty loop body.  */
+	for (i = 0; i < nents; i++, sg++) {
+		sg->address = (char *)(bus_to_baddr[hwdev->bus->number] | __pa(sg->address));
+	}
+
+	return nents;
+}
+
+/*
+ * Unmap a set of streaming mode DMA translations.
+ * Again, cpu read rules concerning calls here are the same as for
+ * pci_unmap_single() above.
+ */
+void pci_unmap_sg(struct pci_dev *hwdev, struct scatterlist *sg, int nents,
+                  int direction)
+{
+	if (direction == PCI_DMA_NONE)
+		BUG();
+
+	/* Nothing to do */
+}
+
+/*
+ * Make physical memory consistent for a single
+ * streaming mode DMA translation after a transfer.
+ *
+ * If you perform a pci_map_single() but wish to interrogate the
+ * buffer using the cpu, yet do not wish to teardown the PCI dma
+ * mapping, you must call this function before doing so.  At the
+ * next point you give the PCI dma address back to the card, the
+ * device again owns the buffer.
+ */
+void pci_dma_sync_single(struct pci_dev *hwdev, dma_addr_t dma_handle,
+                         size_t size, int direction)
+{
+	if (direction == PCI_DMA_NONE)
+		BUG();
+}
+
+/*
+ * Make physical memory consistent for a set of streaming
+ * mode DMA translations after a transfer.
+ *
+ * The same as pci_dma_sync_single but for a scatter-gather list,
+ * same rules and usage.
+ */
+void pci_dma_sync_sg(struct pci_dev *hwdev, struct scatterlist *sg,
+                     int nelems, int direction)
+{
+	if (direction == PCI_DMA_NONE)
+		BUG();
 }