FRV: move DMA macros to scatterlist.h for consistency.

[pandora-kernel.git] / include / asm-frv / scatterlist.h

diff --git a/include/asm-frv/scatterlist.h b/include/asm-frv/scatterlist.h
index 8e827fa..4bca8a2 100644 (file)
--- a/include/asm-frv/scatterlist.h
+++ b/include/asm-frv/scatterlist.h
@@ -4,31 +4,43 @@
 #include <asm/types.h>
 
 /*
- * Drivers must set either ->address or (preferred) ->page and ->offset
+ * Drivers must set either ->address or (preferred) page and ->offset
  * to indicate where data must be transferred to/from.
  *
- * Using ->page is recommended since it handles highmem data as well as
+ * Using page is recommended since it handles highmem data as well as
  * low mem. ->address is restricted to data which has a virtual mapping, and
- * it will go away in the future. Updating to ->page can be automated very
+ * it will go away in the future. Updating to page can be automated very
  * easily -- something like
  *
  * sg->address = some_ptr;
  *
  * can be rewritten as
  *
- * sg->page = virt_to_page(some_ptr);
- * sg->offset = (unsigned long) some_ptr & ~PAGE_MASK;
+ * sg_set_buf(sg, some_ptr, length);
  *
  * and that's it. There's no excuse for not highmem enabling YOUR driver. /jens
  */
 struct scatterlist {
-       struct page     *page;          /* Location for highmem page, if any */
+#ifdef CONFIG_DEBUG_SG
+       unsigned long   sg_magic;
+#endif
+       unsigned long   page_link;
        unsigned int    offset;         /* for highmem, page offset */
 
        dma_addr_t      dma_address;
        unsigned int    length;
 };
 
+/*
+ * These macros should be used after a pci_map_sg call has been done
+ * to get bus addresses of each of the SG entries and their lengths.
+ * You should only work with the number of sg entries pci_map_sg
+ * returns, or alternatively stop on the first sg_dma_len(sg) which
+ * is 0.
+ */
+#define sg_dma_address(sg)     ((sg)->dma_address)
+#define sg_dma_len(sg)         ((sg)->length)
+
 #define ISA_DMA_THRESHOLD (0xffffffffUL)
 
 #endif /* !_ASM_SCATTERLIST_H */