[PATCH] x86_64: Implement early DMI scanning

There are more and more cases where we need to know DMI information
early to work around bugs.  i386 already had early DMI scanning, but
x86-64 didn't.  Implement this now.

This required some cleanup in the i386 code.

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

include/asm-i386/dmi.h

@@ -0,0 +1,11 @@
+#ifndef _ASM_DMI_H
+#define _ASM_DMI_H 1
+
+#include <asm/io.h>
+
+/* Use early IO mappings for DMI because it's initialized early */
+#define dmi_ioremap bt_ioremap
+#define dmi_iounmap bt_iounmap
+#define dmi_alloc alloc_bootmem
+
+#endif

include/asm-x86_64/dmi.h

@@ -0,0 +1,27 @@
+#ifndef _ASM_DMI_H
+#define _ASM_DMI_H 1
+
+#include <asm/io.h>
+
+extern void *dmi_ioremap(unsigned long addr, unsigned long size);
+extern void dmi_iounmap(void *addr, unsigned long size);
+
+#define DMI_MAX_DATA 2048
+
+extern int dmi_alloc_index;
+extern char dmi_alloc_data[DMI_MAX_DATA];
+
+/* This is so early that there is no good way to allocate dynamic memory. 
+   Allocate data in an BSS array. */
+static inline void *dmi_alloc(unsigned len)
+{
+	int idx = dmi_alloc_index;
+	if ((dmi_alloc_index += len) > DMI_MAX_DATA)
+		return NULL;
+	return dmi_alloc_data + idx;
+}
+
+#define dmi_ioremap early_ioremap
+#define dmi_iounmap early_iounmap
+
+#endif

include/asm-x86_64/io.h

@@ -135,6 +135,9 @@ static inline void __iomem * ioremap (unsigned long offset, unsigned long size)
 	return __ioremap(offset, size, 0);
 }
 
+extern void *early_ioremap(unsigned long addr, unsigned long size);
+extern void early_iounmap(void *addr, unsigned long size);
+
 /*
  * This one maps high address device memory and turns off caching for that area.
  * it's useful if some control registers are in such an area and write combining
@@ -143,11 +146,6 @@ static inline void __iomem * ioremap (unsigned long offset, unsigned long size)
 extern void __iomem * ioremap_nocache (unsigned long offset, unsigned long size);
 extern void iounmap(volatile void __iomem *addr);
 
-/* Use normal IO mappings for DMI */
-#define dmi_ioremap ioremap
-#define dmi_iounmap(x,l) iounmap(x)
-#define dmi_alloc(l) kmalloc(l, GFP_ATOMIC)
-
 /*
  * ISA I/O bus memory addresses are 1:1 with the physical address.
  */