DDI_POKE(9F) Kernel Functions for Drivers DDI_POKE(9F)

ddi_poke, ddi_poke8, ddi_poke16, ddi_poke32, ddi_poke64 - write a value to a location

#include <sys/ddi.h>
#include <sys/sunddi.h>
int ddi_poke8(dev_info_t *dip, int8_t *addr, int8_t value);

int ddi_poke16(dev_info_t *dip, int16_t *addr, int16_t value);

int ddi_poke32(dev_info_t *dip, int32_t *addr, int32_t value);

int ddi_poke64(dev_info_t *dip, int64_t *addr, int64_t value);

illumos DDI specific (illumos DDI). The ddi_pokec(), ddi_pokes(), ddi_pokel(), and ddi_poked() functions are obsolete. Use, respectively, ddi_poke8(), ddi_poke16(), ddi_poke32(), and ddi_poke64(), instead.

A pointer to the device's dev_info structure.


Virtual address of the location to be written to.


Value to be written to the location.

These routines cautiously attempt to write a value to a specified virtual address, using the parent nexus driver to assist in the process where necessary.

If the address is not valid, or the value cannot be written without an error occurring, an error code is returned.

These routines are most useful when first trying to establish the presence of a given device on the system in a driver's probe(9E) or attach(9E) routines.

On multiprocessing machines these routines can be extremely heavy-weight, so use the ddi_peek(9F) routines instead if possible.

The value was successfully written to the given virtual address.


An error occurred while trying to write to the location.

These functions can be called from user, interrupt, or kernel context.

attach(9E), probe(9E), ddi_peek(9F)

Writing Device Drivers

January 16, 2006 OmniOS