/*----------------------------------------------------------------------------
 *      RL-ARM - RTX
 *----------------------------------------------------------------------------
 *      Name:    HAL_CM.C
 *      Purpose: Hardware Abstraction Layer for Cortex-M
 *      Rev.:    V4.60
 *----------------------------------------------------------------------------
 *
 * Copyright (c) 1999-2009 KEIL, 2009-2012 ARM Germany GmbH
 * All rights reserved.
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *  - Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *  - Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *  - Neither the name of ARM  nor the names of its contributors may be used
 *    to endorse or promote products derived from this software without
 *    specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL COPYRIGHT HOLDERS AND CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *---------------------------------------------------------------------------*/

#include "rt_TypeDef.h"
#include "RTX_Conf.h"
#include "rt_HAL_CM.h"


/*----------------------------------------------------------------------------
 *      Global Variables
 *---------------------------------------------------------------------------*/

#ifdef DBG_MSG
BIT dbg_msg;
#endif

/*----------------------------------------------------------------------------
 *      Functions
 *---------------------------------------------------------------------------*/


/*--------------------------- rt_init_stack ---------------------------------*/

void rt_init_stack (P_TCB p_TCB, FUNCP task_body) {
  /* Prepare TCB and saved context for a first time start of a task. */
  U32 *stk,i,size;

  /* Prepare a complete interrupt frame for first task start */
  size = p_TCB->priv_stack >> 2;

  /* Write to the top of stack. */
  stk = &p_TCB->stack[size];

  /* Auto correct to 8-byte ARM stack alignment. */
  if ((U32)stk & 0x04) {
    stk--;
  }

  stk -= 16;

  /* Default xPSR and initial PC */
  stk[15] = INITIAL_xPSR;
  stk[14] = (U32)task_body;

  /* Clear R4-R11,R0-R3,R12,LR registers. */
  for (i = 0; i < 14; i++) {
    stk[i] = 0;
  }

  /* Assign a void pointer to R0. */
  stk[8] = (U32)p_TCB->msg;

  /* Initial Task stack pointer. */
  p_TCB->tsk_stack = (U32)stk;

  /* Task entry point. */
  p_TCB->ptask = task_body;

  /* Set a magic word for checking of stack overflow.
   For the main thread (ID: 0x01) the stack is in a memory area shared with the
   heap, therefore the last word of the stack is a moving target.
   We want to do stack/heap collision detection instead.
  */
  if (p_TCB->task_id != 0x01)
      p_TCB->stack[0] = MAGIC_WORD;
}


/*--------------------------- rt_ret_val ----------------------------------*/

static __inline U32 *rt_ret_regs (P_TCB p_TCB) {
  /* Get pointer to task return value registers (R0..R3) in Stack */
#if (__TARGET_FPU_VFP)
  if (p_TCB->stack_frame) {
    /* Extended Stack Frame: R4-R11,S16-S31,R0-R3,R12,LR,PC,xPSR,S0-S15,FPSCR */
    return (U32 *)(p_TCB->tsk_stack + 8*4 + 16*4);
  } else {
    /* Basic Stack Frame: R4-R11,R0-R3,R12,LR,PC,xPSR */
    return (U32 *)(p_TCB->tsk_stack + 8*4);
  }
#else
  /* Stack Frame: R4-R11,R0-R3,R12,LR,PC,xPSR */
  return (U32 *)(p_TCB->tsk_stack + 8*4);
#endif
}

void rt_ret_val (P_TCB p_TCB, U32 v0) {
  U32 *ret;

  ret = rt_ret_regs(p_TCB);
  ret[0] = v0;
}

void rt_ret_val2(P_TCB p_TCB, U32 v0, U32 v1) {
  U32 *ret;

  ret = rt_ret_regs(p_TCB);
  ret[0] = v0;
  ret[1] = v1;
}


/*--------------------------- dbg_init --------------------------------------*/

#ifdef DBG_MSG
void dbg_init (void) {
  if ((DEMCR & DEMCR_TRCENA)     &&
      (ITM_CONTROL & ITM_ITMENA) &&
      (ITM_ENABLE & (1UL << 31))) {
    dbg_msg = __TRUE;
  }
}
#endif

/*--------------------------- dbg_task_notify -------------------------------*/

#ifdef DBG_MSG
void dbg_task_notify (P_TCB p_tcb, BOOL create) {
  while (ITM_PORT31_U32 == 0);
  ITM_PORT31_U32 = (U32)p_tcb->ptask;
  while (ITM_PORT31_U32 == 0);
  ITM_PORT31_U16 = (create << 8) | p_tcb->task_id;
}
#endif

/*--------------------------- dbg_task_switch -------------------------------*/

#ifdef DBG_MSG
void dbg_task_switch (U32 task_id) {
  while (ITM_PORT31_U32 == 0);
  ITM_PORT31_U8 = task_id;
}
#endif


/*----------------------------------------------------------------------------
 * end of file
 *---------------------------------------------------------------------------*/


