ddi_dma_cookie(9S)					    Data Structures for Drivers 					ddi_dma_cookie(9S)

NAME

       ddi_dma_cookie - DMA address cookie

SYNOPSIS

       #include <sys/sunddi.h>

INTERFACE LEVEL

       Solaris DDI specific (Solaris DDI).

DESCRIPTION

       The  ddi_dma_cookie_t  structure contains DMA address information required to program a DMA engine. The structure is filled in by a call to
       ddi_dma_getwin(9F), ddi_dma_addr_bind_handle(9F), or ddi_dma_buf_bind_handle(9F), to get device-specific DMA transfer information for a DMA
       request or a DMA window.

STRUCTURE MEMBERS

       typedef struct {
	      union {
		      uint64_t	      _dmac_ll;       /* 64 bit DMA address */
		      uint32_t	      _dmac_la[2];    /* 2 x 32 bit address */
	      } _dmu;
	      size_t	      dmac_size;      /* DMA cookie size */
	      uint_t	      dmac_type;      /* bus specific type bits */
       } ddi_dma_cookie_t;

       You can access the DMA address through the #defines: dmac_address for 32-bit addresses and dmac_laddress for 64-bit addresses. These macros
       are defined as follows:

       #define dmac_laddress   _dmu._dmac_ll
       #ifdef _LONG_LONG_HTOL
       #define dmac_notused    _dmu._dmac_la[0]
       #define dmac_address    _dmu._dmac_la[1]
       #else
       #define dmac_address    _dmu._dmac_la[0]
       #define dmac_notused    _dmu._dmac_la[1]
       #endif

       dmac_laddress specifies a 64-bit I/O address appropriate for programming the device's DMA engine. If a device has a 64-bit DMA address reg-
       ister  a driver should use this field to program the DMA engine. dmac_address specifies a 32-bit I/O address. It should be used for devices
       that have a 32-bit DMA address register. The I/O address range that the device can address and other DMA attributes have to be specified in
       a ddi_dma_attr(9S) structure.

       dmac_size describes the length of the transfer in bytes.

       dmac_type contains bus-specific type bits, if appropriate. For example, a device on a PCI bus has PCI address modifier bits placed here.

SEE ALSO

       pci(4),	 sbus(4),   sysbus(4),	 ddi_dma_addr_bind_handle(9F),	ddi_dma_buf_bind_handle(9F),  ddi_dma_getwin(9F),  ddi_dma_nextcookie(9F),
       ddi_dma_attr(9S)

       Writing Device Drivers

SunOS 5.10							    30 Sep 1996 						ddi_dma_cookie(9S)