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 /*
  16  * Descriptor structure for PXA's DMA engine
  17  * Note: this structure must always be aligned to a 16-byte boundary.
  18  */
  19
  20 typedef struct pxa_dma_desc {
  21         volatile u32 ddadr;     /* Points to the next descriptor + flags */
  22         volatile u32 dsadr;     /* DSADR value for the current transfer */
  23         volatile u32 dtadr;     /* DTADR value for the current transfer */
  24         volatile u32 dcmd;      /* DCMD value for the current transfer */
  25 } pxa_dma_desc;
  26
  27 typedef enum {
  28         DMA_PRIO_HIGH = 0,
  29         DMA_PRIO_MEDIUM = 1,
  30         DMA_PRIO_LOW = 2
  31 } pxa_dma_prio;
  32
  33 #if defined(CONFIG_PXA27x)
  34
  35 #define PXA_DMA_CHANNELS        32
  36
  37 #define pxa_for_each_dma_prio(ch, prio)                                 \
  38 for (                                                                   \
  39         ch = prio * 4;                                                  \
  40         ch != (4 << prio) + 16;                                         \
  41         ch = (ch + 1 == (4 << prio)) ? (prio * 4 + 16) : (ch + 1)       \
  42 )
  43
  44 #elif defined(CONFIG_PXA25x)
  45
  46 #define PXA_DMA_CHANNELS        16
  47
  48 #define pxa_for_each_dma_prio(ch, prio)                                 \
  49         for (ch = prio * 4; ch != (4 << prio); ch++)
  50
  51 #endif
  52
  53 /*
  54  * DMA registration
  55  */
  56
  57 int pxa_request_dma (char *name,
  58                          pxa_dma_prio prio,
  59                          void (*irq_handler)(int, void *),
  60                          void *data);
  61
  62 void pxa_free_dma (int dma_ch);
  63
  64 #endif /* _ASM_ARCH_DMA_H */