powerpc/dma: handle iommu bypass in dma_iommu_ops

Add a new iommu_bypass flag to struct dev_archdata so that the dma_iommu
implementation can handle the direct mapping transparently instead of
switiching ops around.  Setting of this flag is controlled by new
pci_controller_ops method.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Christian Zigotzky <chzigotzky@xenosoft.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
diff --git a/arch/powerpc/include/asm/device.h b/arch/powerpc/include/asm/device.h
index 0245bfc..1aa5331 100644
--- a/arch/powerpc/include/asm/device.h
+++ b/arch/powerpc/include/asm/device.h
@@ -20,6 +20,11 @@
  */
 struct dev_archdata {
 	/*
+	 * Set to %true if the dma_iommu_ops are requested to use a direct
+	 * window instead of dynamically mapping memory.
+	 */
+	bool			iommu_bypass : 1;
+	/*
 	 * These two used to be a union. However, with the hybrid ops we need
 	 * both so here we store both a DMA offset for direct mappings and
 	 * an iommu_table for remapped DMA.
diff --git a/arch/powerpc/include/asm/dma-mapping.h b/arch/powerpc/include/asm/dma-mapping.h
index ebf6680..ff86b86 100644
--- a/arch/powerpc/include/asm/dma-mapping.h
+++ b/arch/powerpc/include/asm/dma-mapping.h
@@ -29,6 +29,14 @@
 				    struct vm_area_struct *vma,
 				    void *cpu_addr, dma_addr_t handle,
 				    size_t size, unsigned long attrs);
+int dma_nommu_map_sg(struct device *dev, struct scatterlist *sgl,
+		int nents, enum dma_data_direction direction,
+		unsigned long attrs);
+dma_addr_t dma_nommu_map_page(struct device *dev, struct page *page,
+		unsigned long offset, size_t size,
+		enum dma_data_direction dir, unsigned long attrs);
+int dma_nommu_dma_supported(struct device *dev, u64 mask);
+u64 dma_nommu_get_required_mask(struct device *dev);
 
 #ifdef CONFIG_NOT_COHERENT_CACHE
 /*
diff --git a/arch/powerpc/include/asm/pci-bridge.h b/arch/powerpc/include/asm/pci-bridge.h
index aee4fcc..d7492dc 100644
--- a/arch/powerpc/include/asm/pci-bridge.h
+++ b/arch/powerpc/include/asm/pci-bridge.h
@@ -19,6 +19,8 @@
 struct pci_controller_ops {
 	void		(*dma_dev_setup)(struct pci_dev *pdev);
 	void		(*dma_bus_setup)(struct pci_bus *bus);
+	bool		(*iommu_bypass_supported)(struct pci_dev *pdev,
+				u64 mask);
 
 	int		(*probe_mode)(struct pci_bus *bus);