FreeCalypso > hg > fc-tourmaline
view src/nucleus/pis.c @ 214:adfdbcd360fd
backlight evolution: API between Condat driver and MFW
With this change, the API between the Condat backlight driver
and its user in MFW now carries more abstract backlight state codes
(fully off, fully on, in call, charging boot mode) instead of
0-255 levels. This change is needed in order to more properly support
different hardware targets with different capabilities and approaches
in terms of backlight handling.
| author | Mychaela Falconia <falcon@freecalypso.org> |
|---|---|
| date | Fri, 23 Apr 2021 23:52:02 +0000 |
| parents | 4e78acac3d88 |
| children |
line wrap: on
line source
/*************************************************************************/ /* */ /* Copyright Mentor Graphics Corporation 2002 */ /* All Rights Reserved. */ /* */ /* THIS WORK CONTAINS TRADE SECRET AND PROPRIETARY INFORMATION WHICH IS */ /* THE PROPERTY OF MENTOR GRAPHICS CORPORATION OR ITS LICENSORS AND IS */ /* SUBJECT TO LICENSE TERMS. */ /* */ /*************************************************************************/ /*************************************************************************/ /* */ /* FILE NAME VERSION */ /* */ /* pis.c Nucleus PLUS 1.14 */ /* */ /* COMPONENT */ /* */ /* PI - Pipe Management */ /* */ /* DESCRIPTION */ /* */ /* This file contains the supplemental routines for the pipe */ /* management component. */ /* */ /* DATA STRUCTURES */ /* */ /* None */ /* */ /* FUNCTIONS */ /* */ /* PIS_Reset_Pipe Reset a pipe */ /* PIS_Send_To_Front_Of_Pipe Send message to pipe's front */ /* PIS_Broadcast_To_Pipe Broadcast a message to pipe */ /* */ /* DEPENDENCIES */ /* */ /* cs_extr.h Common Service functions */ /* tc_extr.h Thread Control functions */ /* pi_extr.h Pipe functions */ /* hi_extr.h History functions */ /* */ /* HISTORY */ /* */ /* DATE REMARKS */ /* */ /* 03-01-1994 Created initial version 1.1 from */ /* routines originally in core */ /* */ /* 03-18-1994 Verified version 1.1 */ /* 04-17-1996 updated to version 1.2 */ /* 02-04-1998 Corrected SPR434 resulting in */ /* version 1.2a. */ /* 03-24-1998 Released version 1.3 */ /* 03-26-1999 Released 1.11m (new release */ /* numbering scheme) */ /* 04-17-2002 Released version 1.13m */ /* 11-07-2002 Released version 1.14 */ /*************************************************************************/ #define NU_SOURCE_FILE #include "cs_extr.h" /* Common service functions */ #include "tc_extr.h" /* Thread control functions */ #include "pi_extr.h" /* Pipe functions */ #include "hi_extr.h" /* History functions */ #include "profiler.h" /* ProView interface */ /* Define external inner-component global data references. */ extern CS_NODE *PID_Created_Pipes_List; extern UNSIGNED PID_Total_Pipes; extern TC_PROTECT PID_List_Protect; /* Define internal component function prototypes. */ VOID PIC_Cleanup(VOID *information); /*************************************************************************/ /* */ /* FUNCTION */ /* */ /* PIS_Reset_Pipe */ /* */ /* DESCRIPTION */ /* */ /* This function resets the specified pipe back to the original */ /* state. Any messages in the pipe are discarded. Also, any */ /* tasks currently suspended on the pipe are resumed with the */ /* reset status. */ /* */ /* CALLED BY */ /* */ /* Application */ /* PISE_Reset_Pipe Error checking shell */ /* */ /* CALLS */ /* */ /* [HIC_Make_History_Entry] Make entry in history log */ /* TCC_Resume_Task Resume a suspended task */ /* [TCT_Check_Stack] Stack checking function */ /* TCT_Control_To_System Transfer control to system */ /* TCT_System_Protect Protect against system access*/ /* TCT_Unprotect Release protection */ /* */ /* INPUTS */ /* */ /* pipe_ptr Pipe control block pointer */ /* */ /* OUTPUTS */ /* */ /* NU_SUCCESS */ /* */ /* HISTORY */ /* */ /* NAME DATE REMARKS */ /* */ /* 03-01-1993 Created initial version 1.0 */ /* 04-19-1993 Verified version 1.0 */ /* 03-01-1994 Changed function interfaces to */ /* match those in prototype, */ /* added register options, changed */ /* protection logic to reduce */ /* overhead, fixed read and write */ /* pointers to both point at the */ /* start, resulting in version 1.1 */ /* */ /* 03-18-1994 Verified version 1.1 */ /* 02-04-1998 Corrected SPR434. */ /* */ /*************************************************************************/ STATUS PIS_Reset_Pipe(NU_PIPE *pipe_ptr) { R1 PI_PCB *pipe; /* Pipe control block ptr */ PI_SUSPEND *suspend_ptr; /* Suspend block pointer */ PI_SUSPEND *next_ptr; /* Next suspend block pointer*/ STATUS preempt; /* Status for resume call */ NU_SUPERV_USER_VARIABLES /* Switch to supervisor mode */ NU_SUPERVISOR_MODE(); /* Move input pipe pointer into internal pointer. */ pipe = (PI_PCB *) pipe_ptr; #ifdef NU_ENABLE_STACK_CHECK /* Call stack checking function to check for an overflow condition. */ TCT_Check_Stack(); #endif #ifdef NU_ENABLE_HISTORY /* Make an entry that corresponds to this function in the system history log. */ HIC_Make_History_Entry(NU_RESET_PIPE_ID, (UNSIGNED) pipe, (UNSIGNED) 0, (UNSIGNED) 0); #endif /* Protect against access to the pipe. */ TCT_System_Protect(); /* Pickup the suspended task suspension list. */ suspend_ptr = pipe -> pi_suspension_list; /* Walk the chain task(s) currently suspended on the pipe. */ preempt = 0; while (suspend_ptr) { /* Resume the suspended task. Insure that the status returned is NU_PIPE_RESET. */ suspend_ptr -> pi_return_status = NU_PIPE_RESET; /* Point to the next suspend structure in the link. */ next_ptr = (PI_SUSPEND *) (suspend_ptr -> pi_suspend_link.cs_next); /* Resume the specified task. */ preempt = preempt | TCC_Resume_Task((NU_TASK *) suspend_ptr -> pi_suspended_task, NU_PIPE_SUSPEND); /* Determine if the next is the same as the head pointer. */ if (next_ptr == pipe -> pi_suspension_list) /* Clear the suspension pointer to signal the end of the list traversal. */ suspend_ptr = NU_NULL; else /* Position the suspend pointer to the next block. */ suspend_ptr = next_ptr; } /* Pickup the urgent message suspension list. */ suspend_ptr = pipe -> pi_urgent_list; /* Walk the chain task(s) currently suspended on the pipe. */ while (suspend_ptr) { /* Resume the suspended task. Insure that the status returned is NU_PIPE_RESET. */ suspend_ptr -> pi_return_status = NU_PIPE_RESET; /* Point to the next suspend structure in the link. */ next_ptr = (PI_SUSPEND *) (suspend_ptr -> pi_suspend_link.cs_next); /* Resume the specified task. */ preempt = preempt | TCC_Resume_Task((NU_TASK *) suspend_ptr -> pi_suspended_task, NU_PIPE_SUSPEND); /* Determine if the next is the same as the head pointer. */ if (next_ptr == pipe -> pi_urgent_list) /* Clear the suspension pointer to signal the end of the list traversal. */ suspend_ptr = NU_NULL; else /* Position the suspend pointer to the next active block. */ suspend_ptr = next_ptr; } /* Initialize various elements of the pipe. */ pipe -> pi_available = pipe -> pi_end - pipe -> pi_start; pipe -> pi_messages = 0; pipe -> pi_read = pipe -> pi_start; pipe -> pi_write = pipe -> pi_start; pipe -> pi_tasks_waiting = 0; pipe -> pi_suspension_list = NU_NULL; pipe -> pi_urgent_list = NU_NULL; #ifdef INCLUDE_PROVIEW _RTProf_DumpPipe(RT_PROF_RESET_PIPE,pipe,RT_PROF_OK); #endif /* INCLUDE_PROVIEW */ /* Determine if preemption needs to occur. */ if (preempt) /* Transfer control to system to facilitate preemption. */ TCT_Control_To_System(); /* Release protection against access to the pipe. */ TCT_Unprotect(); /* Return to user mode */ NU_USER_MODE(); /* Return a successful completion. */ return(NU_SUCCESS); } /*************************************************************************/ /* */ /* FUNCTION */ /* */ /* PIS_Send_To_Front_Of_Pipe */ /* */ /* DESCRIPTION */ /* */ /* This function sends a message to the front of the specified */ /* message pipe. The message length is determined by the caller. */ /* If there are any tasks suspended on the pipe for a message, the */ /* message is copied into the message area of the first waiting */ /* task and that task is resumed. If there is enough room in the */ /* pipe, the message is copied in front of all other messages. */ /* If there is not enough room in the pipe, suspension of the */ /* caller is possible. */ /* */ /* CALLED BY */ /* */ /* Application */ /* PISE_Send_To_Front_Of_Pipe Error checking shell */ /* */ /* CALLS */ /* */ /* CSC_Place_On_List Place on suspend list */ /* CSC_Remove_From_List Remove from suspend list */ /* [HIC_Make_History_Entry] Make entry in history log */ /* TCC_Resume_Task Resume a suspended task */ /* TCC_Suspend_Task Suspend calling task */ /* [TCT_Check_Stack] Stack checking function */ /* TCT_Control_To_System Transfer control to system */ /* TCT_Current_Thread Pickup current thread pointer*/ /* TCT_System_Protect Protect pipe */ /* TCT_Unprotect Release protection */ /* */ /* INPUTS */ /* */ /* pipe_ptr Pipe control block pointer */ /* message Pointer to message to send */ /* size Size of message to send */ /* suspend Suspension option if full */ /* */ /* OUTPUTS */ /* */ /* NU_SUCCESS If service is successful */ /* NU_PIPE_FULL If pipe is currently full */ /* NU_TIMEOUT If timeout on service expires*/ /* NU_PIPE_DELETED If pipe was deleted during */ /* suspension */ /* NU_PIPE_RESET If pipe was reset during */ /* suspension */ /* */ /* HISTORY */ /* */ /* DATE REMARKS */ /* */ /* 03-01-1993 Created initial version 1.0 */ /* 04-19-1993 Verified version 1.0 */ /* 03-01-1994 Changed function interfaces to */ /* match those in prototype, */ /* added register options, changed */ /* protection logic to reduce */ /* overhead, optimized copy loop, */ /* resulting in version 1.1 */ /* */ /* 03-18-1994 Verified version 1.1 */ /* */ /*************************************************************************/ STATUS PIS_Send_To_Front_Of_Pipe(NU_PIPE *pipe_ptr, VOID *message, UNSIGNED size, UNSIGNED suspend) { R1 PI_PCB *pipe; /* Pipe control block ptr */ PI_SUSPEND suspend_block; /* Allocate suspension block */ PI_SUSPEND *suspend_ptr; /* Pointer to suspend block */ R2 BYTE_PTR source; /* Pointer to source */ R3 BYTE_PTR destination; /* Pointer to destination */ UNSIGNED copy_size; /* Partial copy size */ R4 INT i; /* Working counter */ UNSIGNED pad = 0; /* Number of pad bytes */ TC_TCB *task; /* Task pointer */ STATUS preempt; /* Preempt flag */ STATUS status; /* Completion status */ NU_SUPERV_USER_VARIABLES /* Switch to supervisor mode */ NU_SUPERVISOR_MODE(); /* Move input pipe pointer into internal pointer. */ pipe = (PI_PCB *) pipe_ptr; #ifdef NU_ENABLE_STACK_CHECK /* Call stack checking function to check for an overflow condition. */ TCT_Check_Stack(); #endif #ifdef NU_ENABLE_HISTORY /* Make an entry that corresponds to this function in the system history log. */ HIC_Make_History_Entry(NU_SEND_TO_FRONT_OF_PIPE_ID, (UNSIGNED) pipe, (UNSIGNED) message, (UNSIGNED) size); #endif /* Initialize the status as successful. */ status = NU_SUCCESS; /* Protect against simultaneous access to the pipe. */ TCT_System_Protect(); /* Determine if an extra word of overhead needs to be added to the calculation. */ if (pipe -> pi_fixed_size) /* No overhead. */ i = 0; else { /* Variable messages have one additional word of overhead. */ i = sizeof(UNSIGNED); /* Calculate the number of pad bytes necessary to keep the pipe write pointer on an UNSIGNED data element alignment. */ pad = (((size + sizeof(UNSIGNED) - 1)/sizeof(UNSIGNED)) * sizeof(UNSIGNED)) - size; /* Insure that padding is included in the overhead. */ i = i + ((INT) pad); /* Make special check to see if a suspension needs to be forced for a variable length message. */ if ((pipe -> pi_suspension_list) && (pipe -> pi_messages)) { /* Pickup task control block pointer. */ task = (TC_TCB *) TCT_Current_Thread(); /* Now we know that there are other task(s) are suspended trying to send a variable length message. Determine whether or not a suspension should be forced. */ if ((pipe -> pi_fifo_suspend) || (suspend == NU_NO_SUSPEND) || ((pipe -> pi_suspension_list) -> pi_suspend_link.cs_priority <= TCC_Task_Priority(task))) /* Bump the computed size to avoid placing the new variable length message ahead of the suspended tasks. */ i = (INT) pipe -> pi_available; } } /* Determine if there is enough room in the pipe for the message. */ if (pipe -> pi_available < (size + i)) { /* pipe does not have room for the message. Determine if suspension is required. */ if (suspend) { /* Suspension is requested. */ /* Increment the number of tasks waiting. */ pipe -> pi_tasks_waiting++; #ifdef INCLUDE_PROVIEW _RTProf_DumpPipe(RT_PROF_SEND_TO_FRONT_OF_PIPE,pipe,RT_PROF_WAIT); #endif /* INCLUDE_PROVIEW */ /* Setup the suspend block and suspend the calling task. */ suspend_ptr = &suspend_block; suspend_ptr -> pi_pipe = pipe; suspend_ptr -> pi_suspend_link.cs_next = NU_NULL; suspend_ptr -> pi_suspend_link.cs_previous = NU_NULL; suspend_ptr -> pi_message_area = (BYTE_PTR) message; suspend_ptr -> pi_message_size = size; task = (TC_TCB *) TCT_Current_Thread(); suspend_ptr -> pi_suspended_task = task; /* Place the task on the urgent message suspension list. */ CSC_Place_On_List((CS_NODE **) &(pipe -> pi_urgent_list), &(suspend_ptr -> pi_suspend_link)); /* Move the head pointer of the list to make this suspension the first in the list. */ pipe -> pi_urgent_list = (PI_SUSPEND *) (pipe -> pi_urgent_list) -> pi_suspend_link.cs_previous; /* Finally, suspend the calling task. Note that the suspension call automatically clears the protection on the pipe. */ TCC_Suspend_Task((NU_TASK *) task, NU_PIPE_SUSPEND, PIC_Cleanup, suspend_ptr, suspend); /* Pickup the return status. */ status = suspend_ptr -> pi_return_status; } else { /* Return a status of NU_PIPE_FULL because there is no room in the pipe for the message. */ status = NU_PIPE_FULL; #ifdef INCLUDE_PROVIEW _RTProf_DumpPipe(RT_PROF_SEND_TO_FRONT_OF_PIPE,pipe,RT_PROF_FAIL); #endif /* INCLUDE_PROVIEW */ } } else { /* Determine if a task is waiting on an empty pipe. */ if ((pipe -> pi_suspension_list) && (pipe -> pi_messages == 0)) { /* Task is waiting on pipe for a message. */ /* Decrement the number of tasks waiting on pipe. */ pipe -> pi_tasks_waiting--; #ifdef INCLUDE_PROVIEW _RTProf_DumpPipe(RT_PROF_SEND_TO_FRONT_OF_PIPE,pipe,RT_PROF_OK); #endif /* INCLUDE_PROVIEW */ /* Remove the first suspended block from the list. */ suspend_ptr = pipe -> pi_suspension_list; CSC_Remove_From_List((CS_NODE **) &(pipe -> pi_suspension_list), &(suspend_ptr -> pi_suspend_link)); /* Setup the source and destination pointers. */ source = (BYTE_PTR) message; destination = suspend_ptr -> pi_message_area; /* Initialize the return status. */ suspend_ptr -> pi_return_status = NU_SUCCESS; /* Loop to actually copy the message. */ i = (INT) size; do { *(destination++) = *(source); if ((--i) == 0) break; source++; } while (1); /* Return the size of the message copied. */ suspend_ptr -> pi_actual_size = size; /* Wakeup the waiting task and check for preemption. */ preempt = TCC_Resume_Task((NU_TASK *) suspend_ptr -> pi_suspended_task, NU_PIPE_SUSPEND); /* Determine if preemption needs to take place. */ if (preempt) /* Transfer control to the system if the resumed task function detects a preemption condition. */ TCT_Control_To_System(); } else { /* There is enough room in the pipe and no task is waiting. */ /* Setup the source pointer. */ source = (BYTE_PTR) message; destination = pipe -> pi_read; /* Process according to the type of message supported. */ if (pipe -> pi_fixed_size) { /* Fixed-size message pipe. */ /* Determine if the read pointer is at the top of the pipe area. */ if (destination == pipe -> pi_start) /* Prepare to place the message in the lower part of the pipe area. */ destination = pipe -> pi_end - size; else /* Backup the length of the message from the current read pointer. */ destination = destination - size; /* Adjust the actual read pointer before the copy is done. */ pipe -> pi_read = destination; /* Copy the message into the pipe area. */ i = (INT) size; do { *(destination++) = *(source); if ((--i) == 0) break; source++; } while (1); } else { /* Variable-length message pipe. */ /* Calculate the number of bytes remaining from the write pointer to the bottom of the pipe. */ copy_size = destination - pipe -> pi_start; /* Determine if part of the message needs to be placed at the bottom of the pipe area. */ if (copy_size < (size + i)) /* Compute the starting location for the message. */ destination = pipe -> pi_end - ((size + i) - copy_size); else /* Compute the starting location for the message. */ destination = destination - (size + i); /* Adjust the actual pipe read pointer also. */ pipe -> pi_read = destination; /* Place message size in first location. */ *((UNSIGNED *) destination) = size; destination = destination + sizeof(UNSIGNED); /* Check for a wrap-around condition on the pipe. */ if (destination >= pipe -> pi_end) /* Wrap the write pointer back to the top of the pipe area. */ destination = pipe -> pi_start; /* Decrement the number of bytes remaining for this extra word of overhead. */ pipe -> pi_available = pipe -> pi_available - sizeof(UNSIGNED); /* Calculate the number of bytes remaining from the write pointer to the bottom of the pipe. */ copy_size = pipe -> pi_end - destination; /* Determine if the message needs to be wrapped around the edge of the pipe area. */ if (copy_size >= (size + pad)) { /* Copy the whole message at once. */ i = (INT) size; do { *(destination++) = *(source); if ((--i) == 0) break; source++; } while (1); } else { /* Copy the first half of the message. */ i = (INT) copy_size; do { *(destination) = *(source++); if ((--i) == 0) break; destination++; } while (1); /* Copy the second half of the message. */ destination = pipe -> pi_start; /* Determine if there is anything left to copy. */ if (size > copy_size) { /* Yes, there is something to copy. */ i = (INT) (size - copy_size); do { *(destination++) = *(source); if ((--i) == 0) break; source++; } while (1); } } /* Decrement the number of available bytes. */ pipe -> pi_available = pipe -> pi_available - pad; } /* Decrement the number of available bytes. */ pipe -> pi_available = pipe -> pi_available - size; /* Increment the number of messages in the pipe. */ pipe -> pi_messages++; #ifdef INCLUDE_PROVIEW _RTProf_DumpPipe(RT_PROF_SEND_TO_FRONT_OF_PIPE,pipe,RT_PROF_OK); #endif /* INCLUDE_PROVIEW */ } } /* Release protection against access to the pipe. */ TCT_Unprotect(); /* Return to user mode */ NU_USER_MODE(); /* Return the completion status. */ return(status); } /*************************************************************************/ /* */ /* FUNCTION */ /* */ /* PIS_Broadcast_To_Pipe */ /* */ /* DESCRIPTION */ /* */ /* This function sends a message to all tasks waiting for a message */ /* from the specified pipe. If there are no tasks waiting for a */ /* message the service performs like a standard send request. */ /* */ /* CALLED BY */ /* */ /* Application */ /* PISE_Broadcast_To_Pipe Error checking shell */ /* */ /* CALLS */ /* */ /* CSC_Place_On_List Place on suspend list */ /* CSC_Priority_Place_On_List Place on priority list */ /* CSC_Remove_From_List Remove from suspend list */ /* [HIC_Make_History_Entry] Make entry in history log */ /* TCC_Resume_Task Resume a suspended task */ /* TCC_Suspend_Task Suspend calling task */ /* TCC_Task_Priority Pickup task's priority */ /* [TCT_Check_Stack] Stack checking function */ /* TCT_Control_To_System Transfer control to system */ /* TCT_Current_Thread Pickup current thread pointer*/ /* TCT_System_Protect Protect pipe */ /* TCT_Unprotect Release protection */ /* */ /* INPUTS */ /* */ /* pipe_ptr Pipe control block pointer */ /* message Pointer to message to send */ /* size Size of message to send */ /* suspend Suspension option if full */ /* */ /* OUTPUTS */ /* */ /* NU_SUCCESS If service is successful */ /* NU_PIPE_FULL If pipe is currently full */ /* NU_TIMEOUT If timeout on service expires*/ /* NU_PIPE_DELETED If pipe was deleted during */ /* suspension */ /* NU_PIPE_RESET If pipe was reset during */ /* suspension */ /* */ /* HISTORY */ /* */ /* DATE REMARKS */ /* */ /* 03-01-1993 Created initial version 1.0 */ /* 04-19-1993 Verified version 1.0 */ /* 03-01-1994 Changed function interfaces to */ /* match those in prototype, */ /* added register options, changed */ /* protection logic to reduce */ /* overhead, optimized copy loop, */ /* resulting in version 1.1 */ /* */ /* 03-18-1994 Verified version 1.1 */ /* */ /*************************************************************************/ STATUS PIS_Broadcast_To_Pipe(NU_PIPE *pipe_ptr, VOID *message, UNSIGNED size, UNSIGNED suspend) { R1 PI_PCB *pipe; /* Pipe control block ptr */ PI_SUSPEND suspend_block; /* Allocate suspension block */ PI_SUSPEND *suspend_ptr; /* Pointer to suspend block */ R2 BYTE_PTR source; /* Pointer to source */ R3 BYTE_PTR destination; /* Pointer to destination */ UNSIGNED copy_size; /* Partial copy size */ UNSIGNED pad = 0; /* Number of pad bytes */ R4 INT i; /* Working counter */ TC_TCB *task; /* Task pointer */ STATUS preempt; /* Preempt flag */ STATUS status; /* Completion status */ NU_SUPERV_USER_VARIABLES /* Switch to supervisor mode */ NU_SUPERVISOR_MODE(); /* Move input pipe pointer into internal pointer. */ pipe = (PI_PCB *) pipe_ptr; #ifdef NU_ENABLE_STACK_CHECK /* Call stack checking function to check for an overflow condition. */ TCT_Check_Stack(); #endif #ifdef NU_ENABLE_HISTORY /* Make an entry that corresponds to this function in the system history log. */ HIC_Make_History_Entry(NU_BROADCAST_TO_PIPE_ID, (UNSIGNED) pipe, (UNSIGNED) message, (UNSIGNED) size); #endif /* Initialize the status as successful. */ status = NU_SUCCESS; /* Protect against simultaneous access to the pipe. */ TCT_System_Protect(); /* Determine if an extra word of overhead needs to be added to the calculation. */ if (pipe -> pi_fixed_size) /* No overhead. */ i = 0; else { /* Variable messages have one additional word of overhead. */ i = sizeof(UNSIGNED); /* Calculate the number of pad bytes necessary to keep the pipe write pointer on an UNSIGNED data element alignment. */ pad = (((size + sizeof(UNSIGNED) - 1)/sizeof(UNSIGNED)) * sizeof(UNSIGNED)) - size; /* Insure that padding is included in the overhead. */ i = i + ((INT) pad); /* Make special check to see if a suspension needs to be forced for a variable length message. */ if ((pipe -> pi_suspension_list) && (pipe -> pi_messages)) { /* Pickup task control block pointer. */ task = (TC_TCB *) TCT_Current_Thread(); /* Now we know that there are other task(s) are suspended trying to send a variable length message. Determine whether or not a suspension should be forced. */ if ((pipe -> pi_fifo_suspend) || (suspend == NU_NO_SUSPEND) || ((pipe -> pi_suspension_list) -> pi_suspend_link.cs_priority <= TCC_Task_Priority(task))) /* Bump the computed size to avoid placing the new variable length message ahead of the suspended tasks. */ i = (INT) pipe -> pi_available; } } /* Determine if there is enough room in the pipe for the message. */ if (pipe -> pi_available < (size + i)) { /* pipe does not have room for the message. Determine if suspension is required. */ if (suspend) { /* Suspension is requested. */ /* Increment the number of tasks waiting. */ pipe -> pi_tasks_waiting++; #ifdef INCLUDE_PROVIEW _RTProf_DumpPipe(RT_PROF_BROADCAST_TO_PIPE,pipe,RT_PROF_WAIT); #endif /* INCLUDE_PROVIEW */ /* Setup the suspend block and suspend the calling task. */ suspend_ptr = &suspend_block; suspend_ptr -> pi_pipe = pipe; suspend_ptr -> pi_suspend_link.cs_next = NU_NULL; suspend_ptr -> pi_suspend_link.cs_previous = NU_NULL; suspend_ptr -> pi_message_area = (BYTE_PTR) message; suspend_ptr -> pi_message_size = size; task = (TC_TCB *) TCT_Current_Thread(); suspend_ptr -> pi_suspended_task = task; /* Determine if priority or FIFO suspension is associated with the pipe. */ if (pipe -> pi_fifo_suspend) { /* FIFO suspension is required. Link the suspend block into the list of suspended tasks on this pipe. */ CSC_Place_On_List((CS_NODE **) &(pipe -> pi_suspension_list), &(suspend_ptr -> pi_suspend_link)); } else { /* Get the priority of the current thread so the suspend block can be placed in the appropriate place. */ suspend_ptr -> pi_suspend_link.cs_priority = TCC_Task_Priority(task); CSC_Priority_Place_On_List((CS_NODE **) &(pipe -> pi_suspension_list), &(suspend_ptr -> pi_suspend_link)); } /* Finally, suspend the calling task. Note that the suspension call automatically clears the protection on the pipe. */ TCC_Suspend_Task((NU_TASK *) task, NU_PIPE_SUSPEND, PIC_Cleanup, suspend_ptr, suspend); /* Pickup the return status. */ status = suspend_ptr -> pi_return_status; } else { /* Return a status of NU_PIPE_FULL because there is no room in the pipe for the message. */ status = NU_PIPE_FULL; #ifdef INCLUDE_PROVIEW _RTProf_DumpPipe(RT_PROF_BROADCAST_TO_PIPE,pipe,RT_PROF_FAIL); #endif /* INCLUDE_PROVIEW */ } } else { #ifdef INCLUDE_PROVIEW _RTProf_DumpPipe(RT_PROF_BROADCAST_TO_PIPE,pipe,RT_PROF_OK); #endif /* INCLUDE_PROVIEW */ /* Determine if a task is waiting on an empty pipe. */ if ((pipe -> pi_suspension_list) && (pipe -> pi_messages == 0)) { /* Yes, one or more tasks are waiting for a message from this pipe. */ preempt = 0; do { /* Decrement the number of tasks waiting on pipe. */ pipe -> pi_tasks_waiting--; /* Remove the first suspended block from the list. */ suspend_ptr = pipe -> pi_suspension_list; CSC_Remove_From_List((CS_NODE **) &(pipe -> pi_suspension_list), &(suspend_ptr -> pi_suspend_link)); /* Setup the source and destination pointers. */ source = (BYTE_PTR) message; destination = suspend_ptr -> pi_message_area; /* Initialize the return status. */ suspend_ptr -> pi_return_status = NU_SUCCESS; /* Loop to actually copy the message. */ i = (INT) size; do { *(destination++) = *(source); if ((--i) == 0) break; source++; } while (1); /* Return the size of the message copied. */ suspend_ptr -> pi_actual_size = size; /* Wakeup the waiting task and check for preemption. */ preempt = preempt | TCC_Resume_Task((NU_TASK *) suspend_ptr -> pi_suspended_task, NU_PIPE_SUSPEND); /* Move the suspend pointer to the next node, which is now at the head of the list. */ suspend_ptr = pipe -> pi_suspension_list; } while (suspend_ptr); /* Determine if preemption needs to take place. */ if (preempt) /* Transfer control to the system if the resumed task function detects a preemption condition. */ TCT_Control_To_System(); } else { /* There is enough room in the pipe and no task is waiting. */ /* Setup the source pointer. */ source = (BYTE_PTR) message; destination = pipe -> pi_write; /* Process according to the type of message supported. */ if (pipe -> pi_fixed_size) { /* Fixed-size messages are supported by this pipe. */ /* Loop to copy the message into the pipe area. */ i = (INT) size; do { *(destination++) = *(source); if ((--i) == 0) break; source++; } while (1); } else { /* Variable-size messages are supported. Processing must check for pipe wrap-around conditions. */ /* Place message size in first location. */ *((UNSIGNED *) destination) = size; destination = destination + sizeof(UNSIGNED); /* Check for a wrap-around condition on the pipe. */ if (destination >= pipe -> pi_end) /* Wrap the write pointer back to the top of the pipe area. */ destination = pipe -> pi_start; /* Decrement the number of bytes remaining for this extra word of overhead. */ pipe -> pi_available = pipe -> pi_available - sizeof(UNSIGNED); /* Calculate the number of bytes remaining from the write pointer to the bottom of the pipe. */ copy_size = pipe -> pi_end - destination; /* Determine if the message needs to be wrapped around the edge of the pipe area. */ if (copy_size >= size) { /* Copy the whole message at once. */ i = (INT) size; do { *(destination++) = *(source); if ((--i) == 0) break; source++; } while (1); } else { /* Copy the first half of the message. */ i = (INT) copy_size; do { *(destination) = *(source++); if ((--i) == 0) break; destination++; } while (1); /* Copy the second half of the message. */ destination = pipe -> pi_start; i = (INT) (size - copy_size); do { *(destination++) = *(source); if ((--i) == 0) break; source++; } while (1); } } /* Check again for wrap-around condition on the write pointer. */ if (destination >= pipe -> pi_end) /* Move the write pointer to the top of the pipe area. */ destination = pipe -> pi_start; /* Determine if the pipe supports variable-length messages. If so, pad bytes are needed to keep UNSIGNED alignment. */ if (pad) { /* Variable-size message. Add pad bytes to the write pointer. */ /* Calculate the number of bytes remaining from the write pointer to the bottom of the pipe. */ copy_size = pipe -> pi_end - destination; /* If there is not enough room at the bottom of the pipe, the pad bytes must be wrapped around to the top. */ if (copy_size <= pad) /* Move write pointer to the top of the pipe and make the necessary adjustment. */ destination = pipe -> pi_start + (pad - copy_size); else /* There is enough room in the pipe to simply add the the pad bytes to the write pointer. */ destination = destination + pad; /* Decrement the number of available bytes. */ pipe -> pi_available = pipe -> pi_available - pad; } /* Update the actual write pointer. */ pipe -> pi_write = destination; /* Decrement the number of available bytes. */ pipe -> pi_available = pipe -> pi_available - size; /* Increment the number of messages in the pipe. */ pipe -> pi_messages++; } } /* Release protection against access to the pipe. */ TCT_Unprotect(); /* Return to user mode */ NU_USER_MODE(); /* Return the completion status. */ return(status); }