initpsm(D2psm)

initpsm -- entry point for the PSM

Synopsis

   ms_bool_t pfxinitpsm(void)

Description

initpsm is the initial entry point for a PSM.

All PSMs must export an initpsm entry point. For SVR5 this means that they must contain a function named pfxinitpsm and declare the following line in their Master(DSP/4dsp) file:

   $entry initpsm

initpsm must perform the following tasks:

Perform sufficient hardware initialization and detection to be able to determine operating parameters such as the number of CPUs
Register MSOP entry points that can be called at a later time by the core kernel
Check, set, or both, operating parameters such as the number of CPUs which are relevant to the machine specific hardware that it controls

The initpsm function returns MS_TRUE if the PSM installs itself successfully and MS_FALSE if it does not. A PSM installation may fail because the PSM is wrong for the hardware, or because initpsm attempts to register an MSOP or an MSPARAM parameter that the core kernel does not support. See os_set_msparam(D3psm) for details of MSPARAM parameters. If pfxinitpsm fails, the core kernel may attempt to recover by installing another PSM. In this case, pfxinitpsm must not have set any MSPARAM parameters and must have freed any allocated resources. Wherever possible, it should also have had no visible net side effects on external hardware states.

On successful return from pfxinitpsm, all subsequent calls to MSOPs and other PSM entry points can assume that memory written by pfxinitpsm is visible.

The life of the PSM is considered to extend from when pfxinitpsm returns successfully until the invocation of MSOP_SHUTDOWN(D2psm).

Specific initialization of various subsystems is handled on a per-CPU basis by MSOP_INIT_CPU(D2psm).

Return values

initpsm returns:

MS_FALSE: PSM probe failed
MS_TRUE: PSM probe succeeded: the PSM is in use

References

os_set_msparam(D3psm), MSOP_SHUTDOWN(D2psm), MSOP_INIT_CPU(D2psm)