2 files changed, 22 insertions, 1 deletions

diff --git a/arch/ia64/sn/kernel/xpc_partition.c b/arch/ia64/sn/kernel/xpc_partition.c
index b31d9988a37a..2c3c4a8af553 100644
--- a/arch/ia64/sn/kernel/xpc_partition.c
+++ b/arch/ia64/sn/kernel/xpc_partition.c
@@ -204,6 +204,19 @@ xpc_rsvd_page_init(void)
                                 return NULL;
                         }
                 }
+        } else if (!IS_AMO_ADDRESS((u64) amos_page)) {
+                /*
+                 * EFI's XPBOOT can also set amos_page in the reserved page,
+                 * but it happens to leave it as an uncached physical address
+                 * and we need it to be an uncached virtual, so we'll have to
+                 * convert it.
+                 */
+                if (!IS_AMO_PHYS_ADDRESS((u64) amos_page)) {
+                        dev_err(xpc_part, "previously used amos_page address "
+                                "is bad = 0x%p\n", (void *) amos_page);
+                        return NULL;
+                }
+                amos_page = (AMO_t *) TO_AMO((u64) amos_page);
         }
 
         memset(xpc_vars, 0, sizeof(struct xpc_vars));
@@ -944,7 +957,7 @@ xpc_discovery(void)
 
 /*
  * Given a partid, get the nasids owned by that partition from the
- * remote partitions reserved page.
+ * remote partition's reserved page.
  */
 enum xpc_retval
 xpc_initiate_partid_to_nasids(partid_t partid, void *nasid_mask)
diff --git a/include/asm-ia64/sn/addrs.h b/include/asm-ia64/sn/addrs.h
index 960d626ee589..1bfdfb4d7b01 100644
--- a/include/asm-ia64/sn/addrs.h
+++ b/include/asm-ia64/sn/addrs.h
@@ -136,6 +136,7 @@
  */
 #define CAC_BASE                (CACHED   | AS_CAC_SPACE)
 #define AMO_BASE                (UNCACHED | AS_AMO_SPACE)
+#define AMO_PHYS_BASE           (UNCACHED_PHYS | AS_AMO_SPACE)
 #define GET_BASE                (CACHED   | AS_GET_SPACE)
 
 /*
@@ -161,6 +162,13 @@
 
 
 /*
+ * Macros to test for address type.
+ */
+#define IS_AMO_ADDRESS(x)       (((u64)(x) & (REGION_BITS | AS_MASK)) == AMO_BASE)
+#define IS_AMO_PHYS_ADDRESS(x)  (((u64)(x) & (REGION_BITS | AS_MASK)) == AMO_PHYS_BASE)
+
+
+/*
  * The following definitions pertain to the IO special address
  * space.  They define the location of the big and little windows
  * of any given node.