diff options
Diffstat (limited to 'include/asm-arm26/dma.h')
| -rw-r--r-- | include/asm-arm26/dma.h | 184 |
1 files changed, 184 insertions, 0 deletions
diff --git a/include/asm-arm26/dma.h b/include/asm-arm26/dma.h new file mode 100644 index 0000000..995e223 --- /dev/null +++ b/include/asm-arm26/dma.h @@ -0,0 +1,184 @@ +#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 */ |
