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diff --git a/doc/supplements/hppa1_1/timeSIMHPPA.t b/doc/supplements/hppa1_1/timeSIMHPPA.t deleted file mode 100644 index 11a3984fe6..0000000000 --- a/doc/supplements/hppa1_1/timeSIMHPPA.t +++ /dev/null @@ -1,86 +0,0 @@ -@c -@c COPYRIGHT (c) 1988-2002. -@c On-Line Applications Research Corporation (OAR). -@c All rights reserved. -@c -@c $Id$ -@c - -@chapter HP-7100 Timing Data - -@section Introduction - -The timing data for the PA-RISC version of RTEMS is -provided along with the target dependent aspects concerning the -gathering of the timing data. The hardware platform used to -gather the times is described to give the reader a better -understanding of each directive time provided. Also, provided -is a description of the interrupt latency and the context -switch times as they pertain to the PA-RISC version of RTEMS. - -@section Hardware Platform - -No directive execution times are reported for the -HP-7100 because the target platform was proprietary and -executions times could not be released. - -@section Interrupt Latency - -The maximum period with traps disabled or the -processor interrupt level set to it's highest value inside RTEMS -is less than RTEMS_MAXIMUM_DISABLE_PERIOD -microseconds including the instructions which -disable and re-enable interrupts. The time required for the -HP-7100 to vector an interrupt and for the RTEMS entry overhead -before invoking the user's trap handler are a total of -RTEMS_INTR_ENTRY_RETURNS_TO_PREEMPTING_TASK -microseconds. These combine to yield a worst case interrupt -latency of less than RTEMS_MAXIMUM_DISABLE_PERIOD + -RTEMS_INTR_ENTRY_RETURNS_TO_PREEMPTING_TASK microseconds at 15 Mhz. -[NOTE: The maximum period with interrupts disabled was last -determined for Release RTEMS_RELEASE_FOR_MAXIMUM_DISABLE_PERIOD.] - -It should be noted again that the maximum period with -interrupts disabled within RTEMS for the HP-7100 is hand calculated. - -@section Context Switch - -The RTEMS processor context switch time is RTEMS_NO_FP_CONTEXTS -microsections for the HP-7100 when no floating point context -switch is saved or restored. Saving and restoring the floating -point context adds additional time to the context -switch procedure. Additional execution time is required when a -TASK_SWITCH user extension is configured. The use of the -TASK_SWITCH extension is application dependent. Thus, its -execution time is not considered part of the raw context switch -time. - -Since RTEMS was designed specifically for embedded -missile applications which are floating point intensive, the -executive is optimized to avoid unnecessarily saving and -restoring the state of the numeric coprocessor. On many -processors, the state of the numeric coprocessor is only saved -when an FLOATING_POINT task is dispatched and that task was not -the last task to utilize the coprocessor. In a system with only -one FLOATING_POINT task, the state of the numeric coprocessor -will never be saved or restored. When the first FLOATING_POINT -task is dispatched, RTEMS does not need to save the current -state of the numeric coprocessor. As discussed in the Register -Usage section, on the HP-7100 the every task is considered to be -floating point registers and , as a rsule, every context switch -involves saving and restoring the state of the floating point -unit. - -The following table summarizes the context switch -times for the HP-7100 processor: - -@example -no times are available for the HP-7100 -@end example - -@section Directive Times - -No execution times are available for the HP-7100 -because the target platform was proprietary and no timing -information could be released. - |