1 files changed, 33 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/prom_parse.c b/arch/powerpc/kernel/prom_parse.c
new file mode 100644
index 000000000..6295e646f
--- /dev/null
+++ b/arch/powerpc/kernel/prom_parse.c
@@ -0,0 +1,33 @@
+#undef DEBUG
+
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/ioport.h>
+#include <linux/etherdevice.h>
+#include <linux/of_address.h>
+#include <asm/prom.h>
+
+void of_parse_dma_window(struct device_node *dn, const __be32 *dma_window,
+			 unsigned long *busno, unsigned long *phys,
+			 unsigned long *size)
+{
+	u32 cells;
+	const __be32 *prop;
+
+	/* busno is always one cell */
+	*busno = of_read_number(dma_window, 1);
+	dma_window++;
+
+	prop = of_get_property(dn, "ibm,#dma-address-cells", NULL);
+	if (!prop)
+		prop = of_get_property(dn, "#address-cells", NULL);
+
+	cells = prop ? of_read_number(prop, 1) : of_n_addr_cells(dn);
+	*phys = of_read_number(dma_window, cells);
+
+	dma_window += cells;
+
+	prop = of_get_property(dn, "ibm,#dma-size-cells", NULL);
+	cells = prop ? of_read_number(prop, 1) : of_n_size_cells(dn);
+	*size = of_read_number(dma_window, cells);
+}