dma.h

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#ifndef __PLAT_DMA_H
#define __PLAT_DMA_H

#define DMAC_REG(x) (*((volatile u32 *)(DMAC_REGS_VIRT + (x))))

#define DCSR(n)     DMAC_REG((n) << 2)
#define DALGN       DMAC_REG(0x00a0)  /* DMA Alignment Register */
#define DINT        DMAC_REG(0x00f0)  /* DMA Interrupt Register */
#define DDADR(n)    DMAC_REG(0x0200 + ((n) << 4))
#define DSADR(n)    DMAC_REG(0x0204 + ((n) << 4))
#define DTADR(n)    DMAC_REG(0x0208 + ((n) << 4))
#define DCMD(n)     DMAC_REG(0x020c + ((n) << 4))
#define DRCMR(n)    DMAC_REG((((n) < 64) ? 0x0100 : 0x1100) + \
                 (((n) & 0x3f) << 2))

#define DCSR_RUN    (1 << 31)   /* Run Bit (read / write) */
#define DCSR_NODESC (1 << 30)   /* No-Descriptor Fetch (read / write) */
#define DCSR_STOPIRQEN  (1 << 29)   /* Stop Interrupt Enable (read / write) */
#define DCSR_REQPEND    (1 << 8)    /* Request Pending (read-only) */
#define DCSR_STOPSTATE  (1 << 3)    /* Stop State (read-only) */
#define DCSR_ENDINTR    (1 << 2)    /* End Interrupt (read / write) */
#define DCSR_STARTINTR  (1 << 1)    /* Start Interrupt (read / write) */
#define DCSR_BUSERR (1 << 0)    /* Bus Error Interrupt (read / write) */

#define DCSR_EORIRQEN   (1 << 28)       /* End of Receive Interrupt Enable (R/W) */
#define DCSR_EORJMPEN   (1 << 27)       /* Jump to next descriptor on EOR */
#define DCSR_EORSTOPEN  (1 << 26)       /* STOP on an EOR */
#define DCSR_SETCMPST   (1 << 25)       /* Set Descriptor Compare Status */
#define DCSR_CLRCMPST   (1 << 24)       /* Clear Descriptor Compare Status */
#define DCSR_CMPST  (1 << 10)       /* The Descriptor Compare Status */
#define DCSR_EORINTR    (1 << 9)        /* The end of Receive */

#define DRCMR_MAPVLD    (1 << 7)    /* Map Valid (read / write) */
#define DRCMR_CHLNUM    0x1f        /* mask for Channel Number (read / write) */

#define DDADR_DESCADDR  0xfffffff0  /* Address of next descriptor (mask) */
#define DDADR_STOP  (1 << 0)    /* Stop (read / write) */

#define DCMD_INCSRCADDR (1 << 31)   /* Source Address Increment Setting. */
#define DCMD_INCTRGADDR (1 << 30)   /* Target Address Increment Setting. */
#define DCMD_FLOWSRC    (1 << 29)   /* Flow Control by the source. */
#define DCMD_FLOWTRG    (1 << 28)   /* Flow Control by the target. */
#define DCMD_STARTIRQEN (1 << 22)   /* Start Interrupt Enable */
#define DCMD_ENDIRQEN   (1 << 21)   /* End Interrupt Enable */
#define DCMD_ENDIAN (1 << 18)   /* Device Endian-ness. */
#define DCMD_BURST8 (1 << 16)   /* 8 byte burst */
#define DCMD_BURST16    (2 << 16)   /* 16 byte burst */
#define DCMD_BURST32    (3 << 16)   /* 32 byte burst */
#define DCMD_WIDTH1 (1 << 14)   /* 1 byte width */
#define DCMD_WIDTH2 (2 << 14)   /* 2 byte width (HalfWord) */
#define DCMD_WIDTH4 (3 << 14)   /* 4 byte width (Word) */
#define DCMD_LENGTH 0x01fff     /* length mask (max = 8K - 1) */

/*
 * Descriptor structure for PXA's DMA engine
 * Note: this structure must always be aligned to a 16-byte boundary.
 */

typedef struct pxa_dma_desc {
    volatile u32 ddadr; /* Points to the next descriptor + flags */
    volatile u32 dsadr; /* DSADR value for the current transfer */
    volatile u32 dtadr; /* DTADR value for the current transfer */
    volatile u32 dcmd;  /* DCMD value for the current transfer */
} pxa_dma_desc;

typedef enum {
    DMA_PRIO_HIGH = 0,
    DMA_PRIO_MEDIUM = 1,
    DMA_PRIO_LOW = 2
} pxa_dma_prio;

/*
 * DMA registration
 */

int __init pxa_init_dma(int irq, int num_ch);

int pxa_request_dma (char *name,
             pxa_dma_prio prio,
             void (*irq_handler)(int, void *),
             void *data);

void pxa_free_dma (int dma_ch);

#endif /* __PLAT_DMA_H */