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

ddi_device_copy - copy data from one device register to another device register

#include <sys/ddi.h>
#include <sys/sunddi.h>
int ddi_device_copy(ddi_acc_handle_t src_handle, caddr_t src_addr,
     ssize_t src_advcnt, ddi_acc_handle_t dest_handle,
     caddr_t dest_addr, ssize_t dest_advcnt,
     size_t bytecount, uint_t dev_datasz);

illumos DDI specific (illumos DDI).

The data access handle of the source device.


Base data source address.


Number of dev_datasz units to advance on every access.


The data access handle of the destination device.


Base data destination address.


Number of dev_datasz units to advance on every access.


Number of bytes to transfer.


The size of each data word. Possible values are defined as:


1 byte data size


2 bytes data size


4 bytes data size


8 bytes data size

ddi_device_copy() copies bytecount bytes from the source address, src_addr, to the destination address, dest_addr. The attributes encoded in the access handles, src_handle and dest_handle, govern how data is actually copied from the source to the destination. Only matching data sizes between the source and destination are supported.

Data will automatically be translated to maintain a consistent view between the source and the destination. The translation may involve byte-swapping if the source and the destination devices have incompatible endian characteristics.

The src_advcnt and dest_advcnt arguments specifies the number of dev_datasz units to advance with each access to the device addresses. A value of 0 will use the same source and destination device address on every access. A positive value increments the corresponding device address by certain number of data size units in the next access. On the other hand, a negative value decrements the device address.

The dev_datasz argument determines the size of the data word on each access. The data size must be the same between the source and destination.

ddi_device_copy() returns:


Successfully transferred the data.


The byte count is not a multiple dev_datasz.

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

ddi_regs_map_free(9F), ddi_regs_map_setup(9F)

Writing Device Drivers

November 15, 1996 OmniOS