dma.h

讲述linux的初始化过程

#ifndef _M68K_DMA_H
#define _M68K_DMA_H 1

#include <linux/config.h>

/* it's useless on the m68k, but unfortunately needed by the new
   bootmem allocator (but this should do it for this) */
#define MAX_DMA_ADDRESS PAGE_OFFSET

#define MAX_DMA_CHANNELS 8

extern int request_dma(unsigned int dmanr, const char * device_id);	/* reserve a DMA channel */
extern void free_dma(unsigned int dmanr);	/* release it again */

#ifdef CONFIG_PCI
extern int isa_dma_bridge_buggy;
#else
#define isa_dma_bridge_buggy    (0)
#endif

#endif /* _M68K_DMA_H */