man/man9f/ddi_dma_set_sbus64.9f

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 ddi_dma_set_sbus64 9F "1 Jan 1997" "SunOS 5.11" "Kernel Functions for Drivers"
 NAME
ddi_dma_set_sbus64 - allow 64-bit transfers on SBus
 SYNOPSIS

#include <sys/ddi.h>
#include <sys/sunddi.h>


int ddi_dma_set_sbus64(ddi_dma_handle_t handle, uint_t burstsizes);


 INTERFACE LEVEL

Solaris DDI specific (Solaris DDI).
 PARAMETERS

handle

The handle filled in by a call to ddi_dma_alloc_handle(9F).


burstsizes

The possible burst sizes the device's DMA engine can accept in 64-bit
mode.


 DESCRIPTION

ddi_dma_set_sbus64() informs the system that the device wishes to perform
64-bit data transfers on the SBus. The driver must first allocate a DMA
handle using ddi_dma_alloc_handle(9F) with a ddi_dma_attr(9S)
structure describing the DMA attributes for a 32-bit transfer mode.

burstsizes describes the possible burst sizes the device's DMA
engine can accept in 64-bit mode. It may be distinct from the burst sizes for
32-bit mode set in the ddi_dma_attr(9S) structure. The system will
activate 64-bit SBus transfers if the SBus supports them. Otherwise, the SBus
will operate in 32-bit mode.

After DMA resources have been allocated (see
ddi_dma_addr_bind_handle(9F) or ddi_dma_buf_bind_handle(9F)), the
driver should retrieve the available burst sizes by calling
ddi_dma_burstsizes(9F). This function will return the burst sizes in
64-bit mode if the system was able to activate 64-bit transfers. Otherwise
burst sizes will be returned in 32-bit mode.
 RETURN VALUES

ddi_dma_set_sbus64() returns:

DDI_SUCCESS

Successfully set the SBus to 64-bit mode.


DDI_FAILURE

64-bit mode could not be set.


 CONTEXT

ddi_dma_set_sbus64() can be called from user, kernel, or interrupt
context.
 ATTRIBUTES

See attributes(5) for descriptions of the following attributes:


ATTRIBUTE TYPEATTRIBUTE VALUE
ArchitectureSBus


 SEE ALSO

attributes(5), ddi_dma_addr_bind_handle(9F),
ddi_dma_alloc_handle(9F), ddi_dma_buf_bind_handle(9F),
ddi_dma_burstsizes(9F), ddi_dma_attr(9S)
 NOTES

64-bit SBus mode is activated on a per SBus slot basis. If there are multiple
SBus cards in one slot, they all must operate in 64-bit mode or they all must
operate in 32-bit mode.