ddi_iomin(9F) Kernel Functions for Drivers ddi_iomin(9F)NAMEddi_iomin - find minimum alignment and transfer size for DMA
SYNOPSIS
#include <sys/conf.h>
#include <sys/ddi.h>
#include <sys/sunddi.h>
int ddi_iomin(dev_info_t *dip, int initial, int streaming);
INTERFACE LEVEL
Solaris DDI specific (Solaris DDI). This interface is obsolete.
PARAMETERS
dip A pointer to the device's dev_info structure.
initial The initial minimum DMAtransfer size in bytes. This may
be zero or an appropriate dlim_minxfer value for
device's ddi_dma_lim structure (see
ddi_dma_lim_sparc(9S) or ddi_dma_lim_x86(9S)). This
value must be a power of two.
streaming This argument, if non-zero, indicates that the returned
value should be modified to account for streaming mode
accesses (see ddi_dma_req(9S) for a discussion of
streaming versus non-streaming access mode).
DESCRIPTION
The ddi_iomin() function, finds out the minimum DMAtransfer size for
the device pointed to by dip. This provides a mechanism by which a
driver can determine the effects of underlying caches as well as inter‐
vening bus adapters on the granularity of a DMA transfer.
RETURN VALUES
The ddi_iomin() function returns the minimum DMAtransfer size for the
calling device, or it returns zero, which means that you cannot get
there from here.
CONTEXT
This function can be called from user, interrupt, or kernel context.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
┌─────────────────────────────┬─────────────────────────────┐
│ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
├─────────────────────────────┼─────────────────────────────┤
│Interface Stability │Obsolete │
└─────────────────────────────┴─────────────────────────────┘
SEE ALSOddi_dma_devalign(9F), ddi_dma_setup(9F), ddi_dma_sync(9F),
ddi_dma_lim_sparc(9S), ddi_dma_lim_x86(9S), ddi_dma_req(9S)
Writing Device Drivers
SunOS 5.10 04 Apr 2006 ddi_iomin(9F)