From c27a0d75b33c030965cc97d3d7f571107a673fb4 Mon Sep 17 00:00:00 2001
From: Bryan O'Sullivan <bos@pathscale.com>
Date: Wed, 1 Feb 2006 03:05:16 -0800
Subject: [PATCH] [PATCH] Introduce __iowrite32_copy
This arch-independent routine copies data to a memory-mapped I/O region,
using 32-bit accesses. The naming is double-underscored to make it clear
that it does not guarantee write ordering, nor does it perform a memory
barrier afterwards; the kernel doc also explicitly states this. This style
of access is required by some devices.
This change also introduces include/linux/io.h, at Andrew's suggestion. It
only has one occupant at the moment, but is a logical destination for
oft-replicated contents of include/asm-*/{io,iomap}.h to migrate to.
Signed-off-by: Bryan O'Sullivan <bos@pathscale.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
---
include/linux/io.h | 25 +++++++++++++++++++++++++
lib/Makefile | 2 +-
lib/iomap_copy.c | 42 ++++++++++++++++++++++++++++++++++++++++++
3 files changed, 68 insertions(+), 1 deletion(-)
create mode 100644 include/linux/io.h
create mode 100644 lib/iomap_copy.c
diff --git a/include/linux/io.h b/include/linux/io.h
new file mode 100644
index 0000000000000..85533ec5aaa17
--- /dev/null
+++ b/include/linux/io.h
@@ -0,0 +1,25 @@
+/*
+ * 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.
+ */
+
+#ifndef _LINUX_IO_H
+#define _LINUX_IO_H
+
+#include <asm/io.h>
+
+void __iowrite32_copy(void __iomem *to, const void *from, size_t count);
+
+#endif /* _LINUX_IO_H */
diff --git a/lib/Makefile b/lib/Makefile
index 8535f4d7d1c38..648b2c1242fd9 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -9,7 +9,7 @@ lib-y := errno.o ctype.o string.o vsprintf.o cmdline.o \
lib-y += kobject.o kref.o kobject_uevent.o klist.o
-obj-y += sort.o parser.o halfmd4.o
+obj-y += sort.o parser.o halfmd4.o iomap_copy.o
ifeq ($(CONFIG_DEBUG_KOBJECT),y)
CFLAGS_kobject.o += -DDEBUG
diff --git a/lib/iomap_copy.c b/lib/iomap_copy.c
new file mode 100644
index 0000000000000..a6b1e271d53c0
--- /dev/null
+++ b/lib/iomap_copy.c
@@ -0,0 +1,42 @@
+/*
+ * 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/io.h>
+#include <linux/module.h>
+
+/**
+ * __iowrite32_copy - 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 __attribute__((weak)) __iowrite32_copy(void __iomem *to,
+ const void *from,
+ size_t count)
+{
+ u32 __iomem *dst = to;
+ const u32 *src = from;
+ const u32 *end = src + count;
+
+ while (src < end)
+ __raw_writel(*src++, dst++);
+}
+EXPORT_SYMBOL_GPL(__iowrite32_copy);
--
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