svcadm(8)을 검색하려면 섹션에서 8 을 선택하고, 맨 페이지 이름에 svcadm을 입력하고 검색을 누른다.
ddi_dma_getwin(9f)
ddi_dma_getwin(9F) Kernel Functions ddi_dma_getwin(9F)
NAME
ddi_dma_getwin - activate a new DMA window
SYNOPSIS
#include <sys/ddi.h>
#include <sys/sunddi.h>
int ddi_dma_getwin(ddi_dma_handle_t handle, uint_t win,
off_t *offp, size_t *lenp, ddi_dma_cookie_t *cookiep,
uint_t *ccountp);
INTERFACE LEVEL
Solaris DDI specific (Solaris DDI).
PARAMETERS
handle The DMA handle previously allocated by a call to
ddi_dma_alloc_handle(9F).
win Number of the window to activate.
offp Pointer to an offset. Upon a successful return, offp will
contain the new offset indicating the beginning of the win‐
dow within the object.
lenp Upon a successful return, lenp will contain the size, in
bytes, of the current window.
cookiep A pointer to the first ddi_dma_cookie(9S) structure.
ccountp Upon a successful return, ccountp will contain the number of
cookies for this DMA window.
DESCRIPTION
ddi_dma_getwin() activates a new DMA window. If a DMA resource alloca‐
tion request returns DDI_DMA_PARTIAL_MAP indicating that resources for
less than the entire object were allocated, the current DMA window can
be changed by a call to ddi_dma_getwin().
The caller must first determine the number of DMA windows, N, using
ddi_dma_numwin(9F). ddi_dma_getwin() takes a DMA window number from the
range [0..N-1] as the parameter win and makes it the current DMA win‐
dow.
ddi_dma_getwin() fills in the first DMA cookie pointed to by cookiep
with the appropriate address, length, and bus type. *ccountp is set to
the number of DMA cookies representing this DMA object. Subsequent DMA
cookies must be retrieved using ddi_dma_nextcookie(9F).
ddi_dma_getwin() takes care of underlying resource synchronizations
required to shift the window. However accessing the data prior to or
after moving the window requires further synchronization steps using
ddi_dma_sync(9F).
ddi_dma_getwin() is normally called from an interrupt routine. The
first invocation of the DMA engine is done from the driver. All subse‐
quent invocations of the DMA engine are done from the interrupt rou‐
tine. The interrupt routine checks to see if the request has been com‐
pleted. If it has, the interrupt routine returns without invoking
another DMA transfer. Otherwise, it calls ddi_dma_getwin() to shift the
current window and start another DMA transfer.
RETURN VALUES
ddi_dma_getwin() returns:
DDI_SUCCESS Resources for the specified DMA window are allocated.
DDI_FAILURE win is not a valid window index.
CONTEXT
ddi_dma_getwin() can be called from user, kernel, or interrupt context.
SEE ALSO
ddi_dma_addr_bind_handle(9F), ddi_dma_alloc_handle(9F),
ddi_dma_buf_bind_handle(9F), ddi_dma_nextcookie(9F),
ddi_dma_numwin(9F), ddi_dma_sync(9F), ddi_dma_unbind_handle(9F),
ddi_dma_cookie(9S)
Writing Device Drivers in Oracle Solaris 11.4
Oracle Solaris 11.4 15 Nov 1996 ddi_dma_getwin(9F)