[PATCH] ia64 iomap implementation

This preserves the ioreadX() == inX() semantics (same as i386), since it's
not clear that the speedup of omitting the mf.a for port operations is
worth the risk of breaking drivers.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

include/asm-ia64/io.h

@@ -32,7 +32,8 @@
  */
 #define IO_SPACE_LIMIT		0xffffffffffffffffUL
 
-#define MAX_IO_SPACES			16
+#define MAX_IO_SPACES_BITS		4
+#define MAX_IO_SPACES			(1UL << MAX_IO_SPACES_BITS)
 #define IO_SPACE_BITS			24
 #define IO_SPACE_SIZE			(1UL << IO_SPACE_BITS)
 
@@ -52,10 +53,24 @@ extern unsigned int num_io_spaces;
 
 # ifdef __KERNEL__
 
+/*
+ * All MMIO iomem cookies are in region 6; anything less is a PIO cookie:
+ *	0xCxxxxxxxxxxxxxxx	MMIO cookie (return from ioremap)
+ *	0x000000001SPPPPPP	PIO cookie (S=space number, P..P=port)
+ *
+ * ioread/writeX() uses the leading 1 in PIO cookies (PIO_OFFSET) to catch
+ * code that uses bare port numbers without the prerequisite pci_iomap().
+ */
+#define PIO_OFFSET		(1UL << (MAX_IO_SPACES_BITS + IO_SPACE_BITS))
+#define PIO_MASK		(PIO_OFFSET - 1)
+#define PIO_RESERVED		__IA64_UNCACHED_OFFSET
+#define HAVE_ARCH_PIO_SIZE
+
 #include <asm/intrinsics.h>
 #include <asm/machvec.h>
 #include <asm/page.h>
 #include <asm/system.h>
+#include <asm-generic/iomap.h>
 
 /*
  * Change virtual addresses to physical addresses and vv.

lib/iomap.c

@@ -19,7 +19,10 @@
  *
  * Architectures for which this is not true can't use this generic
  * implementation and should do their own copy.
- *
+ */
+
+#ifndef HAVE_ARCH_PIO_SIZE
+/*
  * We encode the physical PIO addresses (0-0xffff) into the
  * pointer by offsetting them with a constant (0x10000) and
  * assuming that all the low addresses are always PIO. That means
@@ -29,6 +32,7 @@
 #define PIO_OFFSET	0x10000UL
 #define PIO_MASK	0x0ffffUL
 #define PIO_RESERVED	0x40000UL
+#endif
 
 /*
  * Ugly macros are a way of life.