Programmed I/O Device Access

Programmed I/O device access is the act of reading and writing of device registers or device memory by the host CPU. The Solaris DDI provides interfaces for mapping a devices registers or memory by the kernel as well as interfaces for reading and writing to device memory from the driver. These interfaces are designed to enable drivers to be developed that are platform and bus independent, by automatically managing any difference in device and host endianness as well as enforcing any memory store ordering requirements imposed by the device.