include/asm-arm/arch-pxa/dma.h

   1 /*
   2  *  linux/include/asm-arm/arch-pxa/dma.h
   3  *
   4  *  Author:     Nicolas Pitre
   5  *  Created:    Jun 15, 2001
   6  *  Copyright:  MontaVista Software, Inc.
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  */
  12 #ifndef __ASM_ARCH_DMA_H
  13 #define __ASM_ARCH_DMA_H
  14
  15 #define MAX_DMA_ADDRESS         0xffffffff
  16
  17 /* No DMA as the rest of the world see it */
  18 #define MAX_DMA_CHANNELS        0
  19
  20 /*
  21  * Descriptor structure for PXA's DMA engine
  22  * Note: this structure must always be aligned to a 16-byte boundary.
  23  */
  24
  25 typedef struct pxa_dma_desc {
  26         volatile u32 ddadr;     /* Points to the next descriptor + flags */
  27         volatile u32 dsadr;     /* DSADR value for the current transfer */
  28         volatile u32 dtadr;     /* DTADR value for the current transfer */
  29         volatile u32 dcmd;      /* DCMD value for the current transfer */
  30 } pxa_dma_desc;
  31
  32 #if defined(CONFIG_PXA27x)
  33
  34 #define PXA_DMA_CHANNELS        32
  35 #define PXA_DMA_NBCH(prio)      ((prio == DMA_PRIO_LOW) ? 16 : 8)
  36
  37 typedef enum {
  38         DMA_PRIO_HIGH = 0,
  39         DMA_PRIO_MEDIUM = 8,
  40         DMA_PRIO_LOW = 16
  41 } pxa_dma_prio;
  42
  43 #elif defined(CONFIG_PXA25x)
  44
  45 #define PXA_DMA_CHANNELS        16
  46 #define PXA_DMA_NBCH(prio)      ((prio == DMA_PRIO_LOW) ? 8 : 4)
  47
  48 typedef enum {
  49         DMA_PRIO_HIGH = 0,
  50         DMA_PRIO_MEDIUM = 4,
  51         DMA_PRIO_LOW = 8
  52 } pxa_dma_prio;
  53
  54 #endif
  55
  56 /*
  57  * DMA registration
  58  */
  59
  60 int pxa_request_dma (char *name,
  61                          pxa_dma_prio prio,
  62                          void (*irq_handler)(int, void *, struct pt_regs *),
  63                          void *data);
  64
  65 void pxa_free_dma (int dma_ch);
  66
  67 #endif /* _ASM_ARCH_DMA_H */