SCO OpenServer AHDK documentation

SCO OpenServer AHDK documentation

This package contains the AHDK documentation with information about developing drivers for SCO OpenServer Release 5 systems.

This package is a tar file that contains the necessary files. To install this package on your SCO OpenServer system:

Select the "AHDK documentation" package from the Download site.
Follow the instructions on the site to download.
Unpack the files into an appropritae directory:
```
   tar -xvf <filename>
```
Follow the instructions for running AHDKDOCINSTALL script to install the doc into the SCO OpenServer ScoHelp system.

See <point> to view this documentation without installing it on your system.

Note that the HDK documentation set includes the latest version of the SCO OpenServer driver development documentation, but it is not currently available for installation on an SCO OpenServer system. Watch this site for a version that can be downloaded.

The AHDK documentation covers the &everestREL;.0.0 driver interfaces with some information about driver interfaces for earlier SCO operating systems. The bottom of this README file includes additional information related to the SCO OpenServer Release 5.0.4 driver interfaces. See the merged HDK documentation set for information about the SCO OpenServer Release 5.0.5 driver interfaces.

SCO OpenServer Release 5.0.4 driver notes

The rest of this file updates the information in the SCO OpenServer Release 5 AHDK documentation for SCO OpenServer Release 5.0.4.

Changes to memory management functionality

SCO OpenServer Release 5.0.4 includes support for large memory configurations. When implementing this capability, SCO recoded the phystokv( ) in a way that makes drivers developed with the native SCO OpenServer Release 5.0.4 immu.h header file incompatible with earlier operating system releases. The previous behavior will be restored in a future release of SCO OpenServer.

If you need to develop drivers on SCO OpenServer Release 5.0.4 that will run on earlier SCO OpenServer systems:

Click <here> to download the modified immu.h header file.
Replace the <sys/immu.h> header file on your system with this version.

Drivers written to conform to the documented AHDK interfaces can be compiled on SCO OpenServer Release 5.0.0 or SCO OpenServer Release 5.0.2 and run on SCO OpenServer Release 5.0.4 without problems.

Remember that the result of all calls to phystokv( ), kvtophys( ), ptok( ), and ktop( ) should be explicitly type cast. There is no compile-time parameter type checking for these macros, and if the type is wrong, they will silently return the wrong value.

SCODB kernel debugger

The SCODB kernel debugger was revised for SCO OpenServer Release 5.0.4 to provide a user-level interface, support for EMACS-style command line editing, and simplified installation of the debugger. Revised documentation is included in the SCO OpenServer Release 5.0.4 online documentation set.

To install scodb in the kernel, do not install the kaddon package as in earlier releases. Instead, edit the /etc/conf/sdevice.d/scodb file and change the N in the second column to a Y, then relink the kernel and reboot the system. Before running the user-level scodb(ADM) command, you must execute the /etc/conf/pack.d/scodb/bin/mkdef command to set up some files that are required.

Interrupt registration

All SCO OpenServer Release 5.0.0, SCO OpenServer Release 5.0.2, and SCO OpenServer Release 5.0.4 drivers that dynamically register interrupts must use either the idistributed(K_MPX) or sdistributed(K_SCSI) function with the get_intr_arg(K) function. SCO OpenServer Release 5.0.x drivers should not call the add_intr_handler(K) function directly. LR