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Diffstat (limited to 'arch/mn10300/include/asm/dma.h')
-rw-r--r-- | arch/mn10300/include/asm/dma.h | 117 |
1 files changed, 117 insertions, 0 deletions
diff --git a/arch/mn10300/include/asm/dma.h b/arch/mn10300/include/asm/dma.h new file mode 100644 index 000000000..10b77d462 --- /dev/null +++ b/arch/mn10300/include/asm/dma.h @@ -0,0 +1,117 @@ +/* MN10300 ISA DMA handlers and definitions + * + * Copyright (C) 2007 Matsushita Electric Industrial Co., Ltd. + * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public Licence + * as published by the Free Software Foundation; either version + * 2 of the Licence, or (at your option) any later version. + */ +#ifndef _ASM_DMA_H +#define _ASM_DMA_H + +#include <linux/spinlock.h> +#include <asm/io.h> +#include <linux/delay.h> + +#undef MAX_DMA_CHANNELS /* switch off linux/kernel/dma.c */ +#define MAX_DMA_ADDRESS 0xbfffffff + +extern spinlock_t dma_spin_lock; + +static inline unsigned long claim_dma_lock(void) +{ + unsigned long flags; + spin_lock_irqsave(&dma_spin_lock, flags); + return flags; +} + +static inline void release_dma_lock(unsigned long flags) +{ + spin_unlock_irqrestore(&dma_spin_lock, flags); +} + +/* enable/disable a specific DMA channel */ +static inline void enable_dma(unsigned int dmanr) +{ +} + +static inline void disable_dma(unsigned int dmanr) +{ +} + +/* Clear the 'DMA Pointer Flip Flop'. + * Write 0 for LSB/MSB, 1 for MSB/LSB access. + * Use this once to initialize the FF to a known state. + * After that, keep track of it. :-) + * --- In order to do that, the DMA routines below should --- + * --- only be used while holding the DMA lock ! --- + */ +static inline void clear_dma_ff(unsigned int dmanr) +{ +} + +/* set mode (above) for a specific DMA channel */ +static inline void set_dma_mode(unsigned int dmanr, char mode) +{ +} + +/* Set only the page register bits of the transfer address. + * This is used for successive transfers when we know the contents of + * the lower 16 bits of the DMA current address register, but a 64k boundary + * may have been crossed. + */ +static inline void set_dma_page(unsigned int dmanr, char pagenr) +{ +} + + +/* Set transfer address & page bits for specific DMA channel. + * Assumes dma flipflop is clear. + */ +static inline void set_dma_addr(unsigned int dmanr, unsigned int a) +{ +} + + +/* Set transfer size (max 64k for DMA1..3, 128k for DMA5..7) for + * a specific DMA channel. + * You must ensure the parameters are valid. + * NOTE: from a manual: "the number of transfers is one more + * than the initial word count"! This is taken into account. + * Assumes dma flip-flop is clear. + * NOTE 2: "count" represents _bytes_ and must be even for channels 5-7. + */ +static inline void set_dma_count(unsigned int dmanr, unsigned int count) +{ +} + + +/* Get DMA residue count. After a DMA transfer, this + * should return zero. Reading this while a DMA transfer is + * still in progress will return unpredictable results. + * If called before the channel has been used, it may return 1. + * Otherwise, it returns the number of _bytes_ left to transfer. + * + * Assumes DMA flip-flop is clear. + */ +static inline int get_dma_residue(unsigned int dmanr) +{ + return 0; +} + + +/* These are in kernel/dma.c: */ +extern int request_dma(unsigned int dmanr, const char *device_id); +extern void free_dma(unsigned int dmanr); + +/* From PCI */ + +#ifdef CONFIG_PCI +extern int isa_dma_bridge_buggy; +#else +#define isa_dma_bridge_buggy (0) +#endif + +#endif /* _ASM_DMA_H */ |