SCO OpenServer

init(D2oddi)

init, pminit -- initialize a device during system initialization

Synopsis

   void prefixinit(void);
   
   void prefixpminit(void);

Description

The init( ) entry point routine is executed when the system is initialized, before system services are available. It is used to do any required device initialization as well as to dynamically register the driver.

The pminit( ) entry point routine is provided for debuggers so that they are initialized before other initialization code executes and can be used to analyze the initialization.

Arguments

None

Return values

None

Usage

The init( ) routine should do the following:

Do bus-specific registration. PCI buses must be searched first because it is possible that a device on a PCI bus may have an IO base address that is in the EISA/ISA range.
Preallocate contiguous memory segments that will be required by the driver for operations such as DMA transfers.
Initialize data structures required for the driver.
If appropriate, register the driver's base level as multithreaded using the bdistributed(D3oddi), cdistributed(D3oddi), iopolldistributed(D3oddi), scsi_distributed(D3osdi), or sdistributed(D3oddi) function.
If appropriate, call the idistributed(D3oddi) or Sharegister(D3osdi) function to dynamically register the interrupt vector(s) and register the driver's interrupt level as multithreaded.
Call the printcfg(D3oddi) function to display a message on the console when the device is successfully initialized.

pminit( ) should be used only in debuggers and similar software.

Context and synchronization

Initialization context. Most system facilities are not available and interrupts are turned off.

Hardware applicability

All

Version applicability

oddi: 1, 2, 2mp, 3, 3mp, 4, 4mp, 5, 5mp, 6, 6mp

Differences between versions

ODDI version 2 drivers use the add_intr_handler(D3oddi) routine to dynamically register interrupts. ODDI version 3 and later drivers should use idistributed( ) or Sharegister( ) even if the driver's intr(D2oddi) routine is not multithreaded.

SVR5 DDI compatibility

When porting drivers to DDI, the initialization functionality is coded as follows:

DDI 8 and later drivers: Driver initialization functionality is coded in the _load(D2) entry point routine and hardware initialization is coded in the CFG_ADD subfunction to the config(D2) entry point routine. Configuration verification for ISA devices is coded in the CFG_VERIFY subfunction to the config(D2) entry point routine.
DDI 7 and earlier loadable drivers: Most initialization functionality for the driver and the hardware is coded in the _load(D2) entry point routine. Configuration verification functionality for ISA devices is coded in the _verify(D2) entry point routine. Note that all MDI and SDI drivers on SVR5 must be loadable. See ``Dynamically-loadable kernel modules (DLKM)'' in HDK Technical Reference.
DDI 7 and earlier static (non-loadable) drivers: Code initialization functionality in the init(D2) entry point routine, which has the same syntax as the ODDI init( ) routine. Much of the configuration functionality in the init( ) routine must be recoded to conform to DDI functions and conventions for autoconfiguration; see ``Autoconfiguration''.

External dependencies

Drivers that contain an init( ) routine must have an I in the function list of the mdevice(F) file. Drivers that contain a pminit( ) routine must have an P in the function list of the mdevice(F) file. The idtools create an array of init( ) routines that identify the routines to be called.

References

add_intr_handler(D3oddi), bdistributed(D3oddi), cdistributed(D3oddi), idistributed(D3oddi), iopolldistributed(D3oddi), scsi_distributed(D3osdi), printcfg(D3oddi), sdistributed(D3oddi), Sdevregister(D3osdi), Sharegister(D3osdi), start(D2oddi)

init(D2mdi), init(D2osdi)