1 files changed, 25 insertions, 0 deletions

diff --git a/arch/powerpc/kernel/prom_parse.c b/arch/powerpc/kernel/prom_parse.c
index 3934c227549..45df420383c 100644
--- a/arch/powerpc/kernel/prom_parse.c
+++ b/arch/powerpc/kernel/prom_parse.c
@@ -548,3 +548,28 @@ int of_pci_address_to_resource(struct device_node *dev, int bar,
         return __of_address_to_resource(dev, addrp, size, flags, r);
 }
 EXPORT_SYMBOL_GPL(of_pci_address_to_resource);
+
+void of_parse_dma_window(struct device_node *dn, unsigned char *dma_window_prop,
+                unsigned long *busno, unsigned long *phys, unsigned long *size)
+{
+        u32 *dma_window, cells;
+        unsigned char *prop;
+
+        dma_window = (u32 *)dma_window_prop;
+
+        /* busno is always one cell */
+        *busno = *(dma_window++);
+
+        prop = get_property(dn, "ibm,#dma-address-cells", NULL);
+        if (!prop)
+                prop = get_property(dn, "#address-cells", NULL);
+
+        cells = prop ? *(u32 *)prop : prom_n_addr_cells(dn);
+        *phys = of_read_addr(dma_window, cells);
+
+        dma_window += cells;
+
+        prop = get_property(dn, "ibm,#dma-size-cells", NULL);
+        cells = prop ? *(u32 *)prop : prom_n_size_cells(dn);
+        *size = of_read_addr(dma_window, cells);
+}