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fc47897d2c
This patch adds several definitions for device communication, including I/O accessors and ioremap(). The __raw_* accessors are implemented as inline asm to avoid compiler generation of post-indexed accesses (less efficient to emulate in a virtualised environment). Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Tony Lindgren <tony@atomide.com> Acked-by: Nicolas Pitre <nico@linaro.org> Acked-by: Olof Johansson <olof@lixom.net> Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
65 lines
1.4 KiB
C
65 lines
1.4 KiB
C
/*
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* Based on arch/arm/kernel/io.c
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*
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* Copyright (C) 2012 ARM Ltd.
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program. If not, see <http://www.gnu.org/licenses/>.
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*/
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#include <linux/export.h>
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#include <linux/types.h>
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#include <linux/io.h>
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/*
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* Copy data from IO memory space to "real" memory space.
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*/
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void __memcpy_fromio(void *to, const volatile void __iomem *from, size_t count)
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{
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unsigned char *t = to;
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while (count) {
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count--;
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*t = readb(from);
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t++;
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from++;
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}
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}
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EXPORT_SYMBOL(__memcpy_fromio);
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/*
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* Copy data from "real" memory space to IO memory space.
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*/
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void __memcpy_toio(volatile void __iomem *to, const void *from, size_t count)
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{
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const unsigned char *f = from;
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while (count) {
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count--;
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writeb(*f, to);
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f++;
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to++;
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}
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}
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EXPORT_SYMBOL(__memcpy_toio);
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/*
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* "memset" on IO memory space.
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*/
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void __memset_io(volatile void __iomem *dst, int c, size_t count)
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{
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while (count) {
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count--;
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writeb(c, dst);
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dst++;
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}
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}
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EXPORT_SYMBOL(__memset_io);
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