[POWERPC] Refactor 64 bits DMA operations

This patch completely refactors DMA operations for 64 bits powerpc. 32 bits
is untouched for now.

We use the new dev_archdata structure to add the dma operations pointer
and associated data to struct device. While at it, we also add the OF node
pointer and numa node. In the future, we might want to look into merging
that with pci_dn as well.

The old vio, pci-iommu and pci-direct DMA ops are gone. They are now replaced
by a set of generic iommu and direct DMA ops (non PCI specific) that can be
used by bus types. The toplevel implementation is now inline.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 141 insertions, 39 deletions

diff --git a/include/asm-powerpc/dma-mapping.h b/include/asm-powerpc/dma-mapping.h
index 2ab9baf78bb4..8367810c994c 100644
--- a/include/asm-powerpc/dma-mapping.h
+++ b/include/asm-powerpc/dma-mapping.h
@@ -44,26 +44,148 @@ extern void __dma_sync_page(struct page *page, unsigned long offset,
 #endif /* ! CONFIG_NOT_COHERENT_CACHE */
 
 #ifdef CONFIG_PPC64
+/*
+ * DMA operations are abstracted for G5 vs. i/pSeries, PCI vs. VIO
+ */
+struct dma_mapping_ops {
+        void *          (*alloc_coherent)(struct device *dev, size_t size,
+                                dma_addr_t *dma_handle, gfp_t flag);
+        void            (*free_coherent)(struct device *dev, size_t size,
+                                void *vaddr, dma_addr_t dma_handle);
+        dma_addr_t      (*map_single)(struct device *dev, void *ptr,
+                                size_t size, enum dma_data_direction direction);
+        void            (*unmap_single)(struct device *dev, dma_addr_t dma_addr,
+                                size_t size, enum dma_data_direction direction);
+        int             (*map_sg)(struct device *dev, struct scatterlist *sg,
+                                int nents, enum dma_data_direction direction);
+        void            (*unmap_sg)(struct device *dev, struct scatterlist *sg,
+                                int nents, enum dma_data_direction direction);
+        int             (*dma_supported)(struct device *dev, u64 mask);
+        int             (*dac_dma_supported)(struct device *dev, u64 mask);
+        int             (*set_dma_mask)(struct device *dev, u64 dma_mask);
+};
+
+static inline struct dma_mapping_ops *get_dma_ops(struct device *dev)
+{
+        /* We don't handle the NULL dev case for ISA for now. We could
+         * do it via an out of line call but it is not needed for now. The
+         * only ISA DMA device we support is the floppy and we have a hack
+         * in the floppy driver directly to get a device for us.
+         */
+        if (unlikely(dev == NULL || dev->archdata.dma_ops == NULL))
+                return NULL;
+        return dev->archdata.dma_ops;
+}
+
+static inline int dma_supported(struct device *dev, u64 mask)
+{
+        struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
+
+        if (unlikely(dma_ops == NULL))
+                return 0;
+        if (dma_ops->dma_supported == NULL)
+                return 1;
+        return dma_ops->dma_supported(dev, mask);
+}
+
+static inline int dma_set_mask(struct device *dev, u64 dma_mask)
+{
+        struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
+
+        if (unlikely(dma_ops == NULL))
+                return -EIO;
+        if (dma_ops->set_dma_mask != NULL)
+                return dma_ops->set_dma_mask(dev, dma_mask);
+        if (!dev->dma_mask || !dma_supported(dev, *dev->dma_mask))
+                return -EIO;
+        *dev->dma_mask = dma_mask;
+        return 0;
+}
+
+static inline void *dma_alloc_coherent(struct device *dev, size_t size,
+                                       dma_addr_t *dma_handle, gfp_t flag)
+{
+        struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
+
+        BUG_ON(!dma_ops);
+        return dma_ops->alloc_coherent(dev, size, dma_handle, flag);
+}
+
+static inline void dma_free_coherent(struct device *dev, size_t size,
+                                     void *cpu_addr, dma_addr_t dma_handle)
+{
+        struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
+
+        BUG_ON(!dma_ops);
+        dma_ops->free_coherent(dev, size, cpu_addr, dma_handle);
+}
+
+static inline dma_addr_t dma_map_single(struct device *dev, void *cpu_addr,
+                                        size_t size,
+                                        enum dma_data_direction direction)
+{
+        struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
+
+        BUG_ON(!dma_ops);
+        return dma_ops->map_single(dev, cpu_addr, size, direction);
+}
+
+static inline void dma_unmap_single(struct device *dev, dma_addr_t dma_addr,
+                                    size_t size,
+                                    enum dma_data_direction direction)
+{
+        struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
+
+        BUG_ON(!dma_ops);
+        dma_ops->unmap_single(dev, dma_addr, size, direction);
+}
+
+static inline dma_addr_t dma_map_page(struct device *dev, struct page *page,
+                                      unsigned long offset, size_t size,
+                                      enum dma_data_direction direction)
+{
+        struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
+
+        BUG_ON(!dma_ops);
+        return dma_ops->map_single(dev, page_address(page) + offset, size,
+                        direction);
+}
+
+static inline void dma_unmap_page(struct device *dev, dma_addr_t dma_address,
+                                  size_t size,
+                                  enum dma_data_direction direction)
+{
+        struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
+
+        BUG_ON(!dma_ops);
+        dma_ops->unmap_single(dev, dma_address, size, direction);
+}
+
+static inline int dma_map_sg(struct device *dev, struct scatterlist *sg,
+                             int nents, enum dma_data_direction direction)
+{
+        struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
+
+        BUG_ON(!dma_ops);
+        return dma_ops->map_sg(dev, sg, nents, direction);
+}
+
+static inline void dma_unmap_sg(struct device *dev, struct scatterlist *sg,
+                                int nhwentries,
+                                enum dma_data_direction direction)
+{
+        struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
+
+        BUG_ON(!dma_ops);
+        dma_ops->unmap_sg(dev, sg, nhwentries, direction);
+}
 
-extern int dma_supported(struct device *dev, u64 mask);
-extern int dma_set_mask(struct device *dev, u64 dma_mask);
-extern void *dma_alloc_coherent(struct device *dev, size_t size,
-                dma_addr_t *dma_handle, gfp_t flag);
-extern void dma_free_coherent(struct device *dev, size_t size, void *cpu_addr,
-                dma_addr_t dma_handle);
-extern dma_addr_t dma_map_single(struct device *dev, void *cpu_addr,
-                size_t size, enum dma_data_direction direction);
-extern void dma_unmap_single(struct device *dev, dma_addr_t dma_addr,
-                size_t size, enum dma_data_direction direction);
-extern dma_addr_t dma_map_page(struct device *dev, struct page *page,
-                unsigned long offset, size_t size,
-                enum dma_data_direction direction);
-extern void dma_unmap_page(struct device *dev, dma_addr_t dma_address,
-                size_t size, enum dma_data_direction direction);
-extern int dma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
-                enum dma_data_direction direction);
-extern void dma_unmap_sg(struct device *dev, struct scatterlist *sg,
-                int nhwentries, enum dma_data_direction direction);
+
+/*
+ * Available generic sets of operations
+ */
+extern struct dma_mapping_ops dma_iommu_ops;
+extern struct dma_mapping_ops dma_direct_ops;
 
 #else /* CONFIG_PPC64 */
 
@@ -261,25 +383,5 @@ static inline void dma_cache_sync(void *vaddr, size_t size,
         __dma_sync(vaddr, size, (int)direction);
 }
 
-/*
- * DMA operations are abstracted for G5 vs. i/pSeries, PCI vs. VIO
- */
-struct dma_mapping_ops {
-        void *          (*alloc_coherent)(struct device *dev, size_t size,
-                                dma_addr_t *dma_handle, gfp_t flag);
-        void            (*free_coherent)(struct device *dev, size_t size,
-                                void *vaddr, dma_addr_t dma_handle);
-        dma_addr_t      (*map_single)(struct device *dev, void *ptr,
-                                size_t size, enum dma_data_direction direction);
-        void            (*unmap_single)(struct device *dev, dma_addr_t dma_addr,
-                                size_t size, enum dma_data_direction direction);
-        int             (*map_sg)(struct device *dev, struct scatterlist *sg,
-                                int nents, enum dma_data_direction direction);
-        void            (*unmap_sg)(struct device *dev, struct scatterlist *sg,
-                                int nents, enum dma_data_direction direction);
-        int             (*dma_supported)(struct device *dev, u64 mask);
-        int             (*dac_dma_supported)(struct device *dev, u64 mask);
-};
-
 #endif /* __KERNEL__ */
 #endif  /* _ASM_DMA_MAPPING_H */