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https://github.com/AuxXxilium/linux_dsm_epyc7002.git
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6365bead25
Add support for the SA-11x0 DMA driver, which replaces the private API version in arch/arm/mach-sa1100/dma.c. We model this as a set of virtual DMA channels, one for each request signal, and assign the virtual DMA channel to a physical DMA channel when there is work to be done. This allows DMA users to claim their channels, and hold them while not in use, without affecting the availability of the physical channels. Another advantage over this approach, compared to the private version, is that a channel can be reconfigured on the fly without having to release and re-request it - which for the IrDA driver, allows us to use DMA for SIR mode transmit without eating up three physical channels. As IrDA is half-duplex, we actually only need one physical channel, and this architecture allows us to achieve that. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
25 lines
572 B
C
25 lines
572 B
C
/*
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* SA11x0 DMA Engine support
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*
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* Copyright (C) 2012 Russell King
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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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#ifndef __LINUX_SA11X0_DMA_H
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#define __LINUX_SA11X0_DMA_H
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struct dma_chan;
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#if defined(CONFIG_DMA_SA11X0) || defined(CONFIG_DMA_SA11X0_MODULE)
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bool sa11x0_dma_filter_fn(struct dma_chan *, void *);
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#else
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static inline bool sa11x0_dma_filter_fn(struct dma_chan *c, void *d)
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{
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return false;
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}
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#endif
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#endif
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