arch/tile: various header improvements for building drivers

This change adds a number of missing headers in asm (fb.h, parport.h,
serial.h, and vga.h) using the minimal generic versions.

It also adds a number of missing interfaces that showed up as build
failures when trying to build various drivers not normally included in the
"tile" distribution: ioremap_wc(), memset_io(), io{read,write}{16,32}be(),
virt_to_bus(), bus_to_virt(), irq_canonicalize(), __pte(), __pgd(),
and __pmd().  I also added a cast in virt_to_page() since not all callers
pass a pointer.

I fixed <asm/stat.h> to properly include a __KERNEL__ guard for the
__ARCH_WANT_STAT64 symbol, and <asm/swab.h> to use __builtin_bswap32()
even for our 64-bit architecture, since the same code is produced.

I added an export for get_cycles(), since it's used in some modules.

And I made <arch/spr_def.h> properly include the __KERNEL__ guard,
even though it's not yet exported, since it likely will be soon.

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
diff --git a/arch/tile/include/asm/io.h b/arch/tile/include/asm/io.h
index d3cbb9b..c9ea165 100644
--- a/arch/tile/include/asm/io.h
+++ b/arch/tile/include/asm/io.h
@@ -52,6 +52,7 @@
 #endif
 
 #define ioremap_nocache(physaddr, size)		ioremap(physaddr, size)
+#define ioremap_wc(physaddr, size)		ioremap(physaddr, size)
 #define ioremap_writethrough(physaddr, size)	ioremap(physaddr, size)
 #define ioremap_fullcache(physaddr, size)	ioremap(physaddr, size)
 
@@ -161,6 +162,15 @@
 #define iowrite32 writel
 #define iowrite64 writeq
 
+static inline void memset_io(void *dst, int val, size_t len)
+{
+	int x;
+	BUG_ON((unsigned long)dst & 0x3);
+	val = (val & 0xff) * 0x01010101;
+	for (x = 0; x < len; x += 4)
+		writel(val, dst + x);
+}
+
 static inline void memcpy_fromio(void *dst, const volatile void __iomem *src,
 				 size_t len)
 {
@@ -269,6 +279,11 @@
 	ioport_panic();
 }
 
+#define ioread16be(addr)	be16_to_cpu(ioread16(addr))
+#define ioread32be(addr)	be32_to_cpu(ioread32(addr))
+#define iowrite16be(v, addr)	iowrite16(be16_to_cpu(v), (addr))
+#define iowrite32be(v, addr)	iowrite32(be32_to_cpu(v), (addr))
+
 #define ioread8_rep(p, dst, count) \
 	insb((unsigned long) (p), (dst), (count))
 #define ioread16_rep(p, dst, count) \
@@ -283,4 +298,7 @@
 #define iowrite32_rep(p, src, count) \
 	outsl((unsigned long) (p), (src), (count))
 
+#define virt_to_bus     virt_to_phys
+#define bus_to_virt     phys_to_virt
+
 #endif /* _ASM_TILE_IO_H */