powerpc: Merge 32 and 64-bit dma code

We essentially adopt the 64-bit dma code, with some changes to support
32-bit systems, including HIGHMEM.  dma functions on 32-bit are now
invoked via accessor functions which call the correct op for a device based
on archdata dma_ops.  If there is no archdata dma_ops, this defaults
to dma_direct_ops.

In addition, the dma_map/unmap_page functions are added to dma_ops
because we can't just fall back on map/unmap_single when HIGHMEM is
enabled. In the case of dma_direct_*, we stop using map/unmap_single
and just use the page version - this saves a lot of ugly
ifdeffing.  We leave map/unmap_single in the dma_ops definition,
though, because they are needed by the iommu code, which does not
implement map/unmap_page.  Ideally, going forward, we will completely
eliminate map/unmap_single and just have map/unmap_page, if it's
workable for 64-bit.

Signed-off-by: Becky Bruce <becky.bruce@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

1 files changed, 8 insertions, 6 deletions

diff --git a/arch/powerpc/include/asm/pci.h b/arch/powerpc/include/asm/pci.h
index a05a942b1c25..0e52c7828ea4 100644
--- a/arch/powerpc/include/asm/pci.h
+++ b/arch/powerpc/include/asm/pci.h
@@ -60,6 +60,14 @@ static inline int pci_get_legacy_ide_irq(struct pci_dev *dev, int channel)
         return channel ? 15 : 14;
 }
 
+#ifdef CONFIG_PCI
+extern void set_pci_dma_ops(struct dma_mapping_ops *dma_ops);
+extern struct dma_mapping_ops *get_pci_dma_ops(void);
+#else   /* CONFIG_PCI */
+#define set_pci_dma_ops(d)
+#define get_pci_dma_ops()       NULL
+#endif
+
 #ifdef CONFIG_PPC64
 
 /*
@@ -70,9 +78,6 @@ static inline int pci_get_legacy_ide_irq(struct pci_dev *dev, int channel)
 #define PCI_DISABLE_MWI
 
 #ifdef CONFIG_PCI
-extern void set_pci_dma_ops(struct dma_mapping_ops *dma_ops);
-extern struct dma_mapping_ops *get_pci_dma_ops(void);
-
 static inline void pci_dma_burst_advice(struct pci_dev *pdev,
                                         enum pci_dma_burst_strategy *strat,
                                         unsigned long *strategy_parameter)
@@ -89,9 +94,6 @@ static inline void pci_dma_burst_advice(struct pci_dev *pdev,
         *strat = PCI_DMA_BURST_MULTIPLE;
         *strategy_parameter = cacheline_size;
 }
-#else   /* CONFIG_PCI */
-#define set_pci_dma_ops(d)
-#define get_pci_dma_ops()       NULL
 #endif
 
 #else /* 32-bit */