[PATCH] ppc64: support 64k pages

Adds a new CONFIG_PPC_64K_PAGES which, when enabled, changes the kernel
base page size to 64K.  The resulting kernel still boots on any
hardware.  On current machines with 4K pages support only, the kernel
will maintain 16 "subpages" for each 64K page transparently.

Note that while real 64K capable HW has been tested, the current patch
will not enable it yet as such hardware is not released yet, and I'm
still verifying with the firmware architects the proper to get the
information from the newer hypervisors.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 8 insertions, 0 deletions

diff --git a/include/asm-powerpc/prom.h b/include/asm-powerpc/prom.h
index 3a0104fa0462..7587bf5f38c6 100644
--- a/include/asm-powerpc/prom.h
+++ b/include/asm-powerpc/prom.h
@@ -178,6 +178,14 @@ extern struct device_node *of_get_next_child(const struct device_node *node,
 extern struct device_node *of_node_get(struct device_node *node);
 extern void of_node_put(struct device_node *node);
 
+/* For scanning the flat device-tree at boot time */
+int __init of_scan_flat_dt(int (*it)(unsigned long node,
+				     const char *uname, int depth,
+				     void *data),
+			   void *data);
+void* __init of_get_flat_dt_prop(unsigned long node, const char *name,
+				 unsigned long *size);
+
 /* For updating the device tree at runtime */
 extern void of_attach_node(struct device_node *);
 extern void of_detach_node(const struct device_node *);