powerpc/iommu: Remove dma_data union

To support "hybrid" DMA ops in a subsequent patch, we will need both
a direct DMA offset and an iommu pointer. Those are currently exclusive
(a union), so change them to be separate fields.

While there, also type iommu_table_base properly and make exist only
on CONFIG_PPC64 since it's not referenced on 32-bit at all.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
diff --git a/arch/powerpc/include/asm/iommu.h b/arch/powerpc/include/asm/iommu.h
index ca18cff..7b87bab 100644
--- a/arch/powerpc/include/asm/iommu.h
+++ b/arch/powerpc/include/asm/iommu.h
@@ -2,17 +2,17 @@
  * Copyright (C) 2001 Mike Corrigan & Dave Engebretsen, IBM Corporation
  * Rewrite, cleanup:
  * Copyright (C) 2004 Olof Johansson <olof@lixom.net>, IBM Corporation
- * 
+ *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation; either version 2 of the License, or
  * (at your option) any later version.
- * 
+ *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
- * 
+ *
  * You should have received a copy of the GNU General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
@@ -131,16 +131,21 @@
 
 struct scatterlist;
 
-static inline void set_iommu_table_base(struct device *dev, void *base)
+#ifdef CONFIG_PPC64
+
+static inline void set_iommu_table_base(struct device *dev,
+					struct iommu_table *base)
 {
-	dev->archdata.dma_data.iommu_table_base = base;
+	dev->archdata.iommu_table_base = base;
 }
 
 static inline void *get_iommu_table_base(struct device *dev)
 {
-	return dev->archdata.dma_data.iommu_table_base;
+	return dev->archdata.iommu_table_base;
 }
 
+extern int dma_iommu_dma_supported(struct device *dev, u64 mask);
+
 /* Frees table for an individual device node */
 extern void iommu_free_table(struct iommu_table *tbl, const char *node_name);
 
@@ -225,6 +230,20 @@
 }
 #endif /* !CONFIG_IOMMU_API */
 
+#else
+
+static inline void *get_iommu_table_base(struct device *dev)
+{
+	return NULL;
+}
+
+static inline int dma_iommu_dma_supported(struct device *dev, u64 mask)
+{
+	return 0;
+}
+
+#endif /* CONFIG_PPC64 */
+
 extern int ppc_iommu_map_sg(struct device *dev, struct iommu_table *tbl,
 			    struct scatterlist *sglist, int nelems,
 			    unsigned long mask,