Commit c27a0d75 authored by Bryan O'Sullivan's avatar Bryan O'Sullivan Committed by Linus Torvalds
Browse files

[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: default avatarBryan O'Sullivan <bos@pathscale.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent f7589f28

include/linux/io.h

0 → 100644
+25 −0
Original line number Diff line number Diff line 
/*

 * 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 */

lib/Makefile

+1 −1
Original line number Diff line number Diff line
@@ -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

lib/iomap_copy.c

0 → 100644
+42 −0
Original line number Diff line number Diff line 
/*

 * 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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