dma.h

来自「arm_uclinux_tools用于安装linux的编译器」· C头文件 代码 · 共 40 行

#ifndef __ASM_ARCH_DMA_H
#define __ASM_ARCH_DMA_H

/*
 * This is the maximum DMA address that can be DMAd to (since there
 * are only 29 bits in a DMA buffer descriptor source buffer
 * pointer). 
 */
#define MAX_DMA_ADDRESS		0x1fffffff

/*
 * DMA modes - we have two, IN and OUT
 */

/* dmamode_t already defined in asm/dma.h, with 4 modes(?) --rp
typedef enum {
	DMA_MODE_READ,
	DMA_MODE_WRITE
} dmamode_t;
*/

/*
 * There are 10 DMA channels in the DMA controller module.  Normally,
 * this would be channels 0-9.  But on the NET+ARM, there are channels
 * 1-10.  So, we define MAX_DMA_CHANNELS as 11.  This will allow code
 * like "if (channel < MAX_DMA_CHANNELS)" to work properly.
 */
#define MAX_DMA_CHANNELS	11

/*
 * arch_dma_init -- called by arch/armnommu/kernel/dma.c init_dma.
 * Don't know what's needed here (if anything).
 * --gmcnutt
 */
#define arch_dma_init(dma_chan)


#endif /* _ASM_ARCH_DMA_H */