[PATCH 1 of 3] Introduce __raw_memcpy_toio32

["Bryan O'Sullivan" <bos@pathscale.com>]

This arch-independent routine copies data to a memory-mapped I/O region,
using 32-bit accesses.  It does not guarantee access ordering, nor does
it perform a memory barrier afterwards.  This style of access is required
by some devices.

Signed-off-by: Bryan O'Sullivan <bos@pathscale.com>

diff -r 48616306e7bd -r 2d4af213d9c5 lib/Makefile
--- a/lib/Makefile	Tue Jan 10 10:41:42 2006 +0800
+++ b/lib/Makefile	Tue Jan 10 11:52:46 2006 -0800
@@ -21,6 +21,7 @@
 lib-$(CONFIG_RWSEM_XCHGADD_ALGORITHM) += rwsem.o
 lib-$(CONFIG_SEMAPHORE_SLEEPERS) += semaphore-sleepers.o
 lib-$(CONFIG_GENERIC_FIND_NEXT_BIT) += find_next_bit.o
+lib-$(CONFIG_GENERIC_RAW_MEMCPY_IO) += raw_memcpy_io.o
 obj-$(CONFIG_LOCK_KERNEL) += kernel_lock.o
 obj-$(CONFIG_DEBUG_PREEMPT) += smp_processor_id.o
 
diff -r 48616306e7bd -r 2d4af213d9c5 lib/raw_memcpy_io.c
--- /dev/null	Thu Jan  1 00:00:00 1970 +0000
+++ b/lib/raw_memcpy_io.c	Tue Jan 10 11:52:46 2006 -0800
@@ -0,0 +1,39 @@
+/*
+ * Copyright 2006 PathScale, Inc.  All Rights Reserved.
+ *
+ * This file is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+#include <linux/types.h>
+#include <asm/io.h>
+
+/**
+ * __raw_memcpy_toio32 - copy data to MMIO space, in 32-bit units
+ * @to: destination, in MMIO space (must be 32-bit aligned)
+ * @from: source (must be 32-bit aligned)
+ * @count: number of 32-bit quantities to copy
+ *
+ * Copy data from kernel space to MMIO space, in units of 32 bits at a
+ * time.  Order of access is not guaranteed, nor is a memory barrier
+ * performed afterwards.
+ */
+void __raw_memcpy_toio32(void __iomem *to, const void *from, size_t count)
+{
+	u32 __iomem *dst = to;
+	const u32 *src = from;
+	size_t i;
+
+	for (i = 0; i < count; i++)
+		__raw_writel(*src++, dst++);
+}