Writing TURBOchannel Device Drivers Feb94

This document, "Writing TURBOchannel Device Drivers" (Part Number AA-PS3HB-TE, February 1994), is a specialized guide for systems engineers developing device drivers for the TURBOchannel bus on DEC OSF/1 Version 2.0 or higher.

It serves as a companion to general device driver documentation (Volume 1: Tutorial and Volume 2: Reference), focusing specifically on the unique aspects of TURBOchannel. The intended audience is expected to have a strong background in C programming, UNIX systems, core OSF/1 concepts (kernel, shell, process, configuration, autoconfiguration), programming tools, and fundamental CPU hardware architecture (interrupts, DMA, memory mapping, I/O).

The guide covers:

• TURBOchannel Architecture: Discusses the software aspects relevant to driver development, including required header files, handling writes to hardware device registers, Direct Memory Access (DMA) transfers, and device interrupt lines.
• Device Driver Structure: Details the specific sections of a TURBOchannel device driver, such as autoconfiguration support (probe, slave, attach, and unattach interfaces for both static and loadable drivers) and the configure section.
• Kernel I/O Support Interfaces: Explains and provides examples for using TURBOchannel-specific kernel interfaces, including those for enabling/disabling interrupts, determining device names and base addresses, isolating memory errors, ensuring I/O write completion, and managing scatter-gather maps for DMA.
• Device Autoconfiguration: Describes the process of detecting and configuring TURBOchannel devices during system startup, including probing option slots, obtaining module names, mapping slot numbers, and registering interrupt handlers.
• Device Driver Configuration: Covers the use of tc_data files with the mktcdata utility for static configuration and creating tc_option snippet tables for dynamic configuration.
• Reference Information (Appendix A): Provides detailed reference entries for TURBOchannel-specific header files (tc.h), data structures (tc_info, tc_intr_info, tc_memerr_status, tc_option), and kernel/device driver interfaces.