RTEMS 4.7.2 On-Line Library

PowerPC Specific Information CPU Dependent Information Table

RTEMS CPU Architecture Supplement

5.7.1: CPU Dependent Information Table

The PowerPC version of the RTEMS CPU Dependent Information Table is given by the C structure definition is shown below:

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   clicks_per_usec;       /* Timer clicks per microsecond */
  void       (*spurious_handler)(
                unsigned32 vector, CPU_Interrupt_frame *);
  boolean      exceptions_in_RAM;     /* TRUE if in RAM */

#if defined(ppc403)
  unsigned32   serial_per_sec;        /* Serial clocks per second */
  boolean      serial_external_clock;
  boolean      serial_xon_xoff;
  boolean      serial_cts_rts;
  unsigned32   serial_rate;
  unsigned32   timer_average_overhead; /* in ticks */
  unsigned32   timer_least_valid;   /* Least valid number from timer */
#endif
};

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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
clicks_per_usec: is the number of decrementer interupts that occur each microsecond.
spurious_handler: is the address of the routine which is invoked when a spurious interrupt occurs.
exceptions_in_RAM: indicates whether the exception vectors are located in RAM or ROM. If they are located in RAM dynamic vector installation occurs, otherwise it does not.
serial_per_sec: is a PPC403 specific field which specifies the number of clock ticks per second for the PPC403 serial timer.
serial_rate: is a PPC403 specific field which specifies the baud rate for the PPC403 serial port.
serial_external_clock: is a PPC403 specific field which indicates whether or not to mask in a 0x2 into the Input/Output Configuration Register (IOCR) during initialization of the PPC403 console. (NOTE: This bit is defined as "reserved" 6-12?)
serial_xon_xoff: is a PPC403 specific field which indicates whether or not XON/XOFF flow control is supported for the PPC403 serial port.
serial_cts_rts: is a PPC403 specific field which indicates whether or not to set the least significant bit of the Input/Output Configuration Register (IOCR) during initialization of the PPC403 console. (NOTE: This bit is defined as "reserved" 6-12?)
timer_average_overhead: is a PPC403 specific field which specifies the average number of overhead ticks that occur on the PPC403 timer.
timer_least_valid: is a PPC403 specific field which specifies the maximum valid PPC403 timer value.

RTEMS CPU Architecture Supplement