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#ifndef __ASM_ARM_DMA_H
#define __ASM_ARM_DMA_H
typedef unsigned int dmach_t;
#include <linux/config.h>
#include <linux/spinlock.h>
#include <asm/system.h>
#include <asm/memory.h>
#include <asm/scatterlist.h>
// FIXME - do we really need this? arm26 cant do 'proper' DMA
typedef struct dma_struct dma_t;
typedef unsigned int dmamode_t;
struct dma_ops {
int (*request)(dmach_t, dma_t *); /* optional */
void (*free)(dmach_t, dma_t *); /* optional */
void (*enable)(dmach_t, dma_t *); /* mandatory */
void (*disable)(dmach_t, dma_t *); /* mandatory */
int (*residue)(dmach_t, dma_t *); /* optional */
int (*setspeed)(dmach_t, dma_t *, int); /* optional */
char *type;
};
struct dma_struct {
struct scatterlist buf; /* single DMA */
int sgcount; /* number of DMA SG */
struct scatterlist *sg; /* DMA Scatter-Gather List */
unsigned int active:1; /* Transfer active */
unsigned int invalid:1; /* Address/Count changed */
unsigned int using_sg:1; /* using scatter list? */
dmamode_t dma_mode; /* DMA mode */
int speed; /* DMA speed */
unsigned int lock; /* Device is allocated */
const char *device_id; /* Device name */
unsigned int dma_base; /* Controller base address */
int dma_irq; /* Controller IRQ */
int state; /* Controller state */
struct scatterlist cur_sg; /* Current controller buffer */
struct dma_ops *d_ops;
};
/* Prototype: void arch_dma_init(dma)
* Purpose : Initialise architecture specific DMA
* Params : dma - pointer to array of DMA structures
*/
extern void arch_dma_init(dma_t *dma);
extern void isa_init_dma(dma_t *dma);
#define MAX_DMA_ADDRESS 0x03000000
#define MAX_DMA_CHANNELS 3
/* ARC */
#define DMA_VIRTUAL_FLOPPY0 0
#define DMA_VIRTUAL_FLOPPY1 1
#define DMA_VIRTUAL_SOUND 2
/* A5K */
#define DMA_FLOPPY 0
/*
* DMA modes
*/
#define DMA_MODE_MASK 3
#define DMA_MODE_READ 0
#define DMA_MODE_WRITE 1
#define DMA_MODE_CASCADE 2
#define DMA_AUTOINIT 4
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);
}
/* Clear the 'DMA Pointer Flip Flop'.
* Write 0 for LSB/MSB, 1 for MSB/LSB access.
*/
#define clear_dma_ff(channel)
/* Set only the page register bits of the transfer address.
*
* NOTE: This is an architecture specific function, and should
* be hidden from the drivers
*/
extern void set_dma_page(dmach_t channel, char pagenr);
/* Request a DMA channel
*
* Some architectures may need to do allocate an interrupt
*/
extern int request_dma(dmach_t channel, const char * device_id);
/* Free a DMA channel
*
* Some architectures may need to do free an interrupt
*/
extern void free_dma(dmach_t channel);
/* Enable DMA for this channel
*
* On some architectures, this may have other side effects like
* enabling an interrupt and setting the DMA registers.
*/
extern void enable_dma(dmach_t channel);
/* Disable DMA for this channel
*
* On some architectures, this may have other side effects like
* disabling an interrupt or whatever.
*/
extern void disable_dma(dmach_t channel);
/* Test whether the specified channel has an active DMA transfer
*/
extern int dma_channel_active(dmach_t channel);
/* Set the DMA scatter gather list for this channel
*
* This should not be called if a DMA channel is enabled,
* especially since some DMA architectures don't update the
* DMA address immediately, but defer it to the enable_dma().
*/
extern void set_dma_sg(dmach_t channel, struct scatterlist *sg, int nr_sg);
/* Set the DMA address for this channel
*
* This should not be called if a DMA channel is enabled,
* especially since some DMA architectures don't update the
* DMA address immediately, but defer it to the enable_dma().
*/
extern void set_dma_addr(dmach_t channel, unsigned long physaddr);
/* Set the DMA byte count for this channel
*
* This should not be called if a DMA channel is enabled,
* especially since some DMA architectures don't update the
* DMA count immediately, but defer it to the enable_dma().
*/
extern void set_dma_count(dmach_t channel, unsigned long count);
/* Set the transfer direction for this channel
*
* This should not be called if a DMA channel is enabled,
* especially since some DMA architectures don't update the
* DMA transfer direction immediately, but defer it to the
* enable_dma().
*/
extern void set_dma_mode(dmach_t channel, dmamode_t mode);
/* Set the transfer speed for this channel
*/
extern void set_dma_speed(dmach_t channel, int cycle_ns);
/* 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.
*/
extern int get_dma_residue(dmach_t channel);
#ifndef NO_DMA
#define NO_DMA 255
#endif
#endif /* _ARM_DMA_H */
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