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linux/arch/mips/include/asm/dma-coherence.h

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MIPS: Add option to disable software I/O coherency. Some MIPS controllers have hardware I/O coherency. This patch detects those and turns off software coherency. A new kernel command line option also allows the user to manually turn software coherency on or off. Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>
2013-03-26 02:47:29 +08:00
/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 2006 Ralf Baechle <ralf@linux-mips.org>
*
*/
#ifndef __ASM_DMA_COHERENCE_H
#define __ASM_DMA_COHERENCE_H
MIPS: improve checks for noncoherent DMA Only one MIPS development board actually supports enabling/disabling DMA coherency at runtime, so it's not a good idea to push the overhead of checking that configuration setting onto every other supported target as well. Signed-off-by: Felix Fietkau <nbd@openwrt.org> Signed-off-by: John Crispin <blogic@openwrt.org> Patchwork: http://patchwork.linux-mips.org/patch/5912/
2013-09-27 20:41:44 +08:00
#ifdef CONFIG_DMA_MAYBE_COHERENT
MIPS: Add option to disable software I/O coherency. Some MIPS controllers have hardware I/O coherency. This patch detects those and turns off software coherency. A new kernel command line option also allows the user to manually turn software coherency on or off. Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>
2013-03-26 02:47:29 +08:00
extern int coherentio;
extern int hw_coherentio;
MIPS: improve checks for noncoherent DMA Only one MIPS development board actually supports enabling/disabling DMA coherency at runtime, so it's not a good idea to push the overhead of checking that configuration setting onto every other supported target as well. Signed-off-by: Felix Fietkau <nbd@openwrt.org> Signed-off-by: John Crispin <blogic@openwrt.org> Patchwork: http://patchwork.linux-mips.org/patch/5912/
2013-09-27 20:41:44 +08:00
#else
#ifdef CONFIG_DMA_COHERENT
#define coherentio 1
#else
#define coherentio 0
#endif
#define hw_coherentio 0
#endif /* CONFIG_DMA_MAYBE_COHERENT */
MIPS: Add option to disable software I/O coherency. Some MIPS controllers have hardware I/O coherency. This patch detects those and turns off software coherency. A new kernel command line option also allows the user to manually turn software coherency on or off. Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>
2013-03-26 02:47:29 +08:00
#endif