view src/g23m-fad/t30/t30_muxp.c @ 220:0ed36de51973

ABB semaphore protection overhaul The ABB semaphone protection logic that came with TCS211 from TI was broken in several ways: * Some semaphore-protected functions were called from Application_Initialize() context. NU_Obtain_Semaphore() called with NU_SUSPEND fails with NU_INVALID_SUSPEND in this context, but the return value wasn't checked, and NU_Release_Semaphore() would be called unconditionally at the end. The latter call would increment the semaphore count past 1, making the semaphore no longer binary and thus no longer effective for resource protection. The fix is to check the return value from NU_Obtain_Semaphore() and skip the NU_Release_Semaphore() call if the semaphore wasn't properly obtained. * Some SPI hardware manipulation was being done before entering the semaphore- protected critical section. The fix is to reorder the code: first obtain the semaphore, then do everything else. * In the corner case of L1/DSP recovery, l1_abb_power_on() would call some non-semaphore-protected ABB & SPI init functions. The fix is to skip those calls in the case of recovery. * A few additional corner cases existed, all of which are fixed by making ABB semaphore protection 100% consistent for all ABB functions and code paths. There is still one remaining problem of priority inversion: suppose a low- priority task calls an ABB function, and some medium-priority task just happens to preempt right in the middle of that semaphore-protected ABB operation. Then the high-priority SPI task is locked out for a non-deterministic time until that medium-priority task finishes its work and goes back to sleep. This priority inversion problem remains outstanding for now.
author Mychaela Falconia <falcon@freecalypso.org>
date Mon, 26 Apr 2021 20:55:25 +0000
parents fa8dc04885d8
children
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/* 
+----------------------------------------------------------------------------- 
|  Project :  GSM-F&D (8411)
|  Modul   :  t30_muxp
+----------------------------------------------------------------------------- 
|  Copyright 2002 Texas Instruments Berlin, AG 
|                 All rights reserved. 
| 
|                 This file is confidential and a trade secret of Texas 
|                 Instruments Berlin, AG 
|                 The receipt of or possession of this file does not convey 
|                 any rights to reproduce or disclose its contents or to 
|                 manufacture, use, or sell anything it may describe, in 
|                 whole, or in part, without the specific written consent of 
|                 Texas Instruments Berlin, AG. 
+----------------------------------------------------------------------------- 
|  Purpose :  This Modul defines the functions for processing
|             of incomming primitives for the component T30
|             of the mobile station
+----------------------------------------------------------------------------- 
*/ 

#ifndef T30_MUXP_C
#define T30_MUXP_C
#endif

#define ENTITY_T30

/*==== INCLUDES ===================================================*/

#include <string.h>
#include <stdlib.h>
#include <stddef.h>
#include "typedefs.h"
#include "pcm.h"
#include "vsi.h"
#include "macdef.h"
#include "pconst.cdg"
#include "mconst.cdg"
#include "message.h"
#include "ccdapi.h"
#include "custom.h"
#include "gsm.h"
#include "prim.h"
#include "cnf_t30.h"
#include "mon_t30.h"
#include "pei.h"
#include "tok.h"
#include "dti.h"      /* functionality of the dti library */
#include "t30.h"

/*==== CONST =======================================================*/

/*==== TYPES =======================================================*/

/*==== VAR EXPORT ==================================================*/

/*==== VAR LOCAL ===================================================*/

/*==== FUNCTIONS ===================================================*/

/*
+--------------------------------------------------------------------+
| PROJECT : GSM-F&D (8411)             MODULE  : T30_MUXP            |
| STATE   : code                       ROUTINE : mux_fad_mux_ind     |
+--------------------------------------------------------------------+

  PURPOSE : Process primitive FAD_MUX_IND received from FAD.
            This primitive switches the state of the multiplexer.
*/

GLOBAL void mux_fad_mux_ind (T_FAD_MUX_IND *fad_mux_ind)
{
  TRACE_FUNCTION ("mux_fad_mux_ind");
  PACCESS        (fad_mux_ind);

  switch (GET_STATE (MUX))
  {
  case T30_MUX_BCS:
  case T30_MUX_MSG:
    switch (fad_mux_ind->mode)
    {
    case MUX_BCS:
      {
      T_TIME v;
      SET_STATE (MUX, T30_MUX_BCS);

      /* restart timer t4 */
      /* MG: I think the timer should only be restarted, when it is running already: */

      TIMERSTATUS(T4_INDEX, &v);
      if (v)
      {
        TIMERSTART (T4_INDEX, T4_VALUE);
      }
      if (t30_data->preamble_ind)
      {
        PALLOC (t30_preamble_ind, T30_PREAMBLE_IND);
        t30_data->preamble_ind = FALSE;
        PSENDX (MMI, t30_preamble_ind);
      }
      }
      break;

    case MUX_MSG:
      SET_STATE (MUX, T30_MUX_MSG);
      break;
    }
    break;

  default:
#ifdef _SIMULATION_ /* test BCS formatter only */
    if (t30_data->test_mode & TST_BCS)
    {
      switch (fad_mux_ind->mode)
      {
        case MUX_BCS: SET_STATE (MUX, T30_MUX_BCS); break;
      }
    }
#endif
    break;
  }
  PFREE (fad_mux_ind);
}

/*
+--------------------------------------------------------------------+
| PROJECT : GSM-F&D (8411)             MODULE  : T30_MUXP            |
| STATE   : code                       ROUTINE : mux_fad_data_ind    |
+--------------------------------------------------------------------+

  PURPOSE : Process primitive FAD_DATA_IND received from FAD.
            Sends the received data to the message- or the bcs-
            formatter or to nirvana in dependence of the mux-state.
*/

GLOBAL void mux_fad_data_ind (T_FAD_DATA_IND *fad_data_ind)
{
  TRACE_FUNCTION ("mux_fad_data_ind()");
  PACCESS (fad_data_ind);

  switch (GET_STATE (MUX))
  {
  case T30_MUX_BCS:
#if defined _SIMULATION_ || defined KER_DEBUG_BCS
    ker_debug ("FAD_DATA_IND", fad_data_ind->sdu.buf, (USHORT)(fad_data_ind->sdu.l_buf >> 3));
#endif
    sig_mux_bcs_bcs_ind (fad_data_ind);
    break;
  
  case T30_MUX_MSG:
    sig_mux_msg_msg_ind (fad_data_ind);
    break;

  default:
    break;
  }

  PFREE (fad_data_ind);
}