pdiag_dd_big_dma_setup

Edit online

The pdiag_dd_big_dma_setup() function initializes, pins, and cross-memory attaches a large user buffer for a DMA operation. The size can be up to DIAG_MULTIPAGESIZE (currently, this is 0x8000) bytes.

Syntax


#include <sys/pdiagex_dds.h>
#include <sys/dma.h>
int32 pdiag_dd_big_dma_setup( 
handle, dma_flags, baddr, users_daddr, count, minxfer,operation )
pdiag_info_handle_t handle;
int32 dma_flags;
pdiag_addr_t baddr;
pdiag_addr_t users_daddr;
uint32 count;
uint32 minxfer;
uint32 operation;

Description

Attention:
  • This function is not supported for Micro Channel or 60X bus type adapters.
  • At this time, you can only use this call if the bus type is BUS_BID.
  • The operation argument to this function must be PDIAG_DMA_MASTER.
The following is performed by the pdiag_dd_big_dma_setup function depending on the bus type and operation:
  • The pdiag_dd_big_dma_setup() function cross-memory attaches, pins, and maps the user buffer for DMA access by the device. The function currently allows for a transfer sizes greater than 0x1000 bytes, up to DIAG_MULTIPAGESIZE (which is 0x8000 bytes). The resulting bus addresses are mapped as a contiguous space.
  • This function issues the d_map_list kernel call for the specified address. The DMA space is managed for the user.
The following are requirements that must be met in order to use the pdiag_dd_big_dma_setup() function:
  • The device-dependant structure (DDS) member maxmaster, which was previously set with pdiag_open(), must have been set to the maximum number of concurrent pdiag_dd_dma_setup()s and pdiag_dd_big_dma_setup()s to be used (that is, the maximum number of pdiag_dd_dma_setup()s and pdiag_dd_big_dma_setup()s called above the number of associated pdiag_dd_dma_complete()s and pdiag_dd_big_dma_complete()s at any given time). maxmaster must be set to at least 1 (one) for this call to pass without a DGX_BOUND_FAIL error.
  • The DMA_CONTIGUOUS flag must have been set on the DDS member dma_flags, which was previously set with pdiag_open(), This function returns only a single bus address as a result of the memory mapping operation. The DMA_CONTIGUOUS flag is used to request that the mapping returns only a single address space, rather than a list of discontiguous bus memory regions.

Execution Environment

The diag_dd_big_dma_setup() function can be called from the process environment only.

Parameters

Parameter Description
handle Points to pdiag_info_handle_t structure, which is returned from pdiag_open().
dma_flags Use the DMA_READ flag for transferring data from the adapter to user memory. Use 0 (zero) for transferring data from the system to the adapter. For more information on other DMA flags, see the sys/dma.h header file.
baddr Points to the user's read or write buffer where the DMA transfer should take place.
users_daddr Points to an integer to be filled with the bus memory address of baddr upon successful completion of this call.
count Number of bytes to be transferred.

Return Value

The pdiag_dd_big_dma_setup function returns one of the following values:

Return Value Description
DGX_OK The operation was successful. The errno is not set.
DGX_INVALID_HANDLE Specified handle has been closed or was not generated by the pdiag_open() call. The errno is not set.
DGX_BOUND_FAIL The application tried to set up a DMA outside its resources, the count is too large, the resources are currently unavailable, or maxmaster is set to zero. The errno is not set.
DGX_BADVAL_FAIL PDIAGEX was unable to update the specified daddr. This might be because the DMA_CONTIGUOUS flag was not set as described above, or other causes. The errno is set to the suword() return code.
DGX_PINU_FAIL The application could not pin the specified user buffer. The errno is set to the pinu() return code.
DGX_XMATTACH_FAIL The application could not attach user buffer to the physical address. The errno is set to the xmattach() return code.
DGX_XMALLOC_FAIL The function could not allocate necessary temporary memory. The errno is not set.
DGX_FAIL The user memory could not be mapped to bus memory space. The errno is set to the return code from the d_map_list() call.