kernel-ark/include/asm-sh/dma.h
Paul Mundt 0d831770b1 [PATCH] sh: DMA updates
This extends the current SH DMA API somewhat to support a proper virtual
channel abstraction, and also works to represent this through the driver model
by giving each DMAC its own platform device.

There's also a few other minor changes to support a few new CPU subtypes, and
make TEI generation for the SH DMAC configurable.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-16 23:15:27 -08:00

152 lines
3.9 KiB
C

/*
* include/asm-sh/dma.h
*
* Copyright (C) 2003, 2004 Paul Mundt
*
* 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.
*/
#ifndef __ASM_SH_DMA_H
#define __ASM_SH_DMA_H
#ifdef __KERNEL__
#include <linux/config.h>
#include <linux/spinlock.h>
#include <linux/wait.h>
#include <linux/sysdev.h>
#include <linux/device.h>
#include <asm/cpu/dma.h>
#include <asm/semaphore.h>
/* The maximum address that we can perform a DMA transfer to on this platform */
/* Don't define MAX_DMA_ADDRESS; it's useless on the SuperH and any
occurrence should be flagged as an error. */
/* But... */
/* XXX: This is not applicable to SuperH, just needed for alloc_bootmem */
#define MAX_DMA_ADDRESS (PAGE_OFFSET+0x10000000)
#ifdef CONFIG_NR_DMA_CHANNELS
# define MAX_DMA_CHANNELS (CONFIG_NR_DMA_CHANNELS)
#else
# define MAX_DMA_CHANNELS (CONFIG_NR_ONCHIP_DMA_CHANNELS)
#endif
/*
* Read and write modes can mean drastically different things depending on the
* channel configuration. Consult your DMAC documentation and module
* implementation for further clues.
*/
#define DMA_MODE_READ 0x00
#define DMA_MODE_WRITE 0x01
#define DMA_MODE_MASK 0x01
#define DMA_AUTOINIT 0x10
/*
* DMAC (dma_info) flags
*/
enum {
DMAC_CHANNELS_CONFIGURED = 0x00,
DMAC_CHANNELS_TEI_CAPABLE = 0x01,
};
/*
* DMA channel capabilities / flags
*/
enum {
DMA_TEI_CAPABLE = 0x01,
DMA_CONFIGURED = 0x02,
};
extern spinlock_t dma_spin_lock;
struct dma_channel;
struct dma_ops {
int (*request)(struct dma_channel *chan);
void (*free)(struct dma_channel *chan);
int (*get_residue)(struct dma_channel *chan);
int (*xfer)(struct dma_channel *chan);
void (*configure)(struct dma_channel *chan, unsigned long flags);
};
struct dma_channel {
char dev_id[16];
unsigned int chan; /* Physical channel number */
unsigned int vchan; /* Virtual channel number */
unsigned int mode;
unsigned int count;
unsigned long sar;
unsigned long dar;
unsigned long flags;
atomic_t busy;
struct semaphore sem;
wait_queue_head_t wait_queue;
struct sys_device dev;
};
struct dma_info {
struct platform_device *pdev;
const char *name;
unsigned int nr_channels;
unsigned long flags;
struct dma_ops *ops;
struct dma_channel *channels;
struct list_head list;
};
#define to_dma_channel(channel) container_of(channel, struct dma_channel, dev)
/* arch/sh/drivers/dma/dma-api.c */
extern int dma_xfer(unsigned int chan, unsigned long from,
unsigned long to, size_t size, unsigned int mode);
#define dma_write(chan, from, to, size) \
dma_xfer(chan, from, to, size, DMA_MODE_WRITE)
#define dma_write_page(chan, from, to) \
dma_write(chan, from, to, PAGE_SIZE)
#define dma_read(chan, from, to, size) \
dma_xfer(chan, from, to, size, DMA_MODE_READ)
#define dma_read_page(chan, from, to) \
dma_read(chan, from, to, PAGE_SIZE)
extern int request_dma(unsigned int chan, const char *dev_id);
extern void free_dma(unsigned int chan);
extern int get_dma_residue(unsigned int chan);
extern struct dma_info *get_dma_info(unsigned int chan);
extern struct dma_channel *get_dma_channel(unsigned int chan);
extern void dma_wait_for_completion(unsigned int chan);
extern void dma_configure_channel(unsigned int chan, unsigned long flags);
extern int register_dmac(struct dma_info *info);
extern void unregister_dmac(struct dma_info *info);
#ifdef CONFIG_SYSFS
/* arch/sh/drivers/dma/dma-sysfs.c */
extern int dma_create_sysfs_files(struct dma_channel *, struct dma_info *);
extern void dma_remove_sysfs_files(struct dma_channel *, struct dma_info *);
#else
#define dma_create_sysfs_file(channel, info) do { } while (0)
#define dma_remove_sysfs_file(channel, info) do { } while (0)
#endif
#ifdef CONFIG_PCI
extern int isa_dma_bridge_buggy;
#else
#define isa_dma_bridge_buggy (0)
#endif
#endif /* __KERNEL__ */
#endif /* __ASM_SH_DMA_H */