[PATCH] ia64: ioremap: check EFI for valid memory attributes

Check the EFI memory map so we can use the correct memory attributes for
ioremap().  Previously, we always used uncacheable access, which blows up on
some machines for regular system memory.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Matt Domsch <Matt_Domsch@dell.com>
Cc: "Tolentino, Matthew E" <matthew.e.tolentino@intel.com>
Cc: "Brown, Len" <len.brown@intel.com>
Cc: Andi Kleen <ak@muc.de>
Acked-by: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 43 insertions, 0 deletions

diff --git a/arch/ia64/mm/ioremap.c b/arch/ia64/mm/ioremap.c
new file mode 100644
index 000000000000..62328621f99c
--- /dev/null
+++ b/arch/ia64/mm/ioremap.c
@@ -0,0 +1,43 @@
+/*
+ * (c) Copyright 2006 Hewlett-Packard Development Company, L.P.
+ *      Bjorn Helgaas <bjorn.helgaas@hp.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/compiler.h>
+#include <linux/module.h>
+#include <linux/efi.h>
+#include <asm/io.h>
+
+static inline void __iomem *
+__ioremap (unsigned long offset, unsigned long size)
+{
+        return (void __iomem *) (__IA64_UNCACHED_OFFSET | offset);
+}
+
+void __iomem *
+ioremap (unsigned long offset, unsigned long size)
+{
+        if (efi_mem_attribute_range(offset, size, EFI_MEMORY_UC))
+                return __ioremap(offset, size);
+
+        if (efi_mem_attribute_range(offset, size, EFI_MEMORY_WB))
+                return phys_to_virt(offset);
+
+        /*
+         * Someday this should check ACPI resources so we
+         * can do the right thing for hot-plugged regions.
+         */
+        return __ioremap(offset, size);
+}
+EXPORT_SYMBOL(ioremap);
+
+void __iomem *
+ioremap_nocache (unsigned long offset, unsigned long size)
+{
+        return __ioremap(offset, size);
+}
+EXPORT_SYMBOL(ioremap_nocache);