x86, olpc: Add support for calling into OpenFirmware

Add support for saving OFW's cif, and later calling into it to run OFW
commands.  OFW remains resident in memory, living within virtual range
0xff800000 - 0xffc00000.  A single page directory entry points to the
pgdir that OFW actually uses, so rather than saving the entire page
table, we grab and install that one entry permanently in the kernel's
page table.

This is currently only used by the OLPC XO.  Note that this particular
calling convention breaks PAE and PAT, and so cannot be used on newer
x86 hardware.

Signed-off-by: Andres Salomon <dilinger@queued.net>
LKML-Reference: <20100618174653.7755a39a@dev.queued.net>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

1 files changed, 5 insertions, 7 deletions

diff --git a/arch/x86/kernel/olpc.c b/arch/x86/kernel/olpc.c
index 8297160c41b3..156605281f56 100644
--- a/arch/x86/kernel/olpc.c
+++ b/arch/x86/kernel/olpc.c
@@ -21,10 +21,7 @@
 #include <asm/geode.h>
 #include <asm/setup.h>
 #include <asm/olpc.h>
-
-#ifdef CONFIG_OPEN_FIRMWARE
-#include <asm/ofw.h>
-#endif
+#include <asm/olpc_ofw.h>
 
 struct olpc_platform_t olpc_platform_info;
 EXPORT_SYMBOL_GPL(olpc_platform_info);
@@ -188,14 +185,15 @@ err:
 }
 EXPORT_SYMBOL_GPL(olpc_ec_cmd);
 
-#ifdef CONFIG_OPEN_FIRMWARE
+#ifdef CONFIG_OLPC_OPENFIRMWARE
 static void __init platform_detect(void)
 {
         size_t propsize;
         __be32 rev;
+        void *args[] = { NULL, "board-revision-int", &rev, (void *)4 };
+        void *res[] = { &propsize };
 
-        if (ofw("getprop", 4, 1, NULL, "board-revision-int", &rev, 4,
-                        &propsize) || propsize != 4) {
+        if (olpc_ofw("getprop", args, res) || propsize != 4) {
                 printk(KERN_ERR "ofw: getprop call failed!\n");
                 rev = cpu_to_be32(0);
         }