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diff --git a/doc/porting/cpuinit.t b/doc/porting/cpuinit.t deleted file mode 100644 index a1ae785615..0000000000 --- a/doc/porting/cpuinit.t +++ /dev/null @@ -1,150 +0,0 @@ -@c -@c COPYRIGHT (c) 1988-1999. -@c On-Line Applications Research Corporation (OAR). -@c All rights reserved. -@c -@c $Id$ -@c - -@chapter CPU Initialization - -This section describes the general CPU and system initialization sequence -as it pertains to the CPU dependent code. - -@section Introduction - -XXX general startup sequence description rewritten to make it more -applicable to CPU depdent code in executive - -@section CPU Dependent Configuration Table - -The CPU Dependent Configuration Table contains information which tailors -the behavior of RTEMS base Some of the fields in this table are required -to be present in all ports of RTEMS. These fields appear at the beginning -of the data structure. Fields past this point may be CPU family and CPU -model dependent. For example, a port may add a field to specify the -default value for an interrupt mask register on the CPU. This table is -initialized by the Board Support Package and passed to the -rtems_initialize_executive or rtems_initialize_executive_early directive. - -@example -typedef struct @{ - void (*pretasking_hook)( void ); - void (*predriver_hook)( void ); - void (*postdriver_hook)( void ); - void (*idle_task)( void ); - boolean do_zero_of_workspace; - unsigned32 idle_task_stack_size; - unsigned32 interrupt_stack_size; - unsigned32 extra_mpci_receive_server_stack; - void * (*stack_allocate_hook)( unsigned32 ); - void (*stack_free_hook)( void* ); - /* end of fields required on all CPUs */ - - unsigned32 some_other_cpu_dependent_info; -@} rtems_cpu_table; -@end example - -@table @code -@item pretasking_hook -is the address of the user provided routine which is invoked -once RTEMS APIs are initialized. This routine will be invoked -before any system tasks are created. Interrupts are disabled. -This field may be NULL to indicate that the hook is not utilized. - -@item predriver_hook -is the address of the user provided -routine that is invoked immediately before the -the device drivers and MPCI are initialized. RTEMS -initialization is complete but interrupts and tasking are disabled. -This field may be NULL to indicate that the hook is not utilized. - -@item postdriver_hook -is the address of the user provided -routine that is invoked immediately after the -the device drivers and MPCI are initialized. RTEMS -initialization is complete but interrupts and tasking are disabled. -This field may be NULL to indicate that the hook is not utilized. - -@item idle_task -is the address of the optional user -provided routine which is used as the system's IDLE task. If -this field is not NULL, then the RTEMS default IDLE task is not -used. This field may be NULL to indicate that the default IDLE -is to be used. - -@item do_zero_of_workspace -indicates whether RTEMS should -zero the Workspace as part of its initialization. If set to -TRUE, the Workspace is zeroed. Otherwise, it is not. - -@item idle_task_stack_size -is the size of the RTEMS idle task stack in bytes. -If this number is less than MINIMUM_STACK_SIZE, then the -idle task's stack will be MINIMUM_STACK_SIZE in byte. - -@item interrupt_stack_size -is the size of the RTEMS allocated interrupt stack in bytes. -This value must be at least as large as MINIMUM_STACK_SIZE. - -@item extra_mpci_receive_server_stack -is the extra stack space allocated for the RTEMS MPCI receive server task -in bytes. The MPCI receive server may invoke nearly all directives and -may require extra stack space on some targets. - -@item stack_allocate_hook -is the address of the optional user provided routine which allocates -memory for task stacks. If this hook is not NULL, then a stack_free_hook -must be provided as well. - -@item stack_free_hook -is the address of the optional user provided routine which frees -memory for task stacks. If this hook is not NULL, then a stack_allocate_hook -must be provided as well. - -@end table - -@section Initializing the CPU - -The _CPU_Initialize routine performs processor dependent initialization. - -@example -void _CPU_Initialize( - rtems_cpu_table *cpu_table, - void (*thread_dispatch) /* may be ignored */ -) -@end example - -The thread_dispatch argument is the address of the entry point for the -routine called at the end of an ISR once it has been decided a context -switch is necessary. On some compilation systems it is difficult to call -a high-level language routine from assembly. Providing the address of the -_Thread_ISR_Dispatch routine allows the porter an easy way to obtain this -critical address and thus provides an easy way to work around this -limitation on these systems. - -If you encounter this problem save the entry point in a CPU dependent -variable as shown below: - -@example -_CPU_Thread_dispatch_pointer = thread_dispatch; -@end example - - -During the initialization of the context for tasks with floating point, -the CPU dependent code is responsible for initializing the floating point -context. If there is not an easy way to initialize the FP context during -Context_Initialize, then it is usually easier to save an "uninitialized" -FP context here and copy it to the task's during Context_Initialize. If -this technique is used to initialize the FP contexts, then it is important -to ensure that the state of the floating point unit is in a coherent, -initialized state. - -Finally, this routine is responsible for copying the application's CPU -Table into a locally accessible and modifiable area. This is shown below: - -@example -_CPU_Table = *cpu_table; -@end example - - |