ddi_dma_set_sbus64(9F) Kernel Functions for Drivers ddi_dma_set_sbus64(9F)
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. Other-
wise, 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 TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|Architecture |SBus |
+-----------------------------+-----------------------------+
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.
SunOS 5.10 1 Jan 1997 ddi_dma_set_sbus64(9F)
