view src/cs/layer1/gtt_include/ctm/ctm_receiver.h @ 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 4e78acac3d88
children
line wrap: on
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/*
*******************************************************************************
*
*      COPYRIGHT (C) 2000 BY ERICSSON EUROLAB DEUTSCHLAND GmbH
*      90411 NUERNBERG, GERMANY, Tel Int + 49 911 5217 100
*
*      The program(s) may be used and/or copied only with the
*      written permission from Ericsson or in accordance
*      with the terms and conditions stipulated in the agreement or
*      contract under which the program(s) have been supplied.
*
*******************************************************************************
*
*      File             : ctm_receiver.h
*      Author           : EEDN/RV Matthias Doerbecker
*      Tested Platforms : Sun Solaris, Windows NT 4.0
*      Description      : header file for ctm_receiver.c
*
*      Changes since October 13, 2000:
*      - added reset function reset_ctm_receiver()
*
*      $Log: $
*
*******************************************************************************
*/
#ifndef ctm_receiver_h
#define ctm_receiver_h "$Id: $"

/*
*******************************************************************************
*                         INCLUDE FILES
*******************************************************************************
*/

#include "init_interleaver.h"
//#include "tonedemod.h"
#include "wait_for_sync.h"
#include "conv_poly.h"
#include "viterbi.h"
#include "ctm_typedefs.h"
#include "fifo.h"

#include <stdlib.h>
#include <stdio.h> 


/* ******************************************************************/
/* Type definitions for variables that contain all states of the    */
/* Cellular Text Telephone Modem (CTM) Transmitter and Receiver,    */
/* respectively.                                                    */
/* ******************************************************************/

typedef struct {
  /* simple variables */
  WORD16    samplingCorrection;
  WORD16    numBitsWithLowReliability;
  WORD16    cntIdleSymbols;
  WORD16    numDeintlBits;
  WORD16    cntRXBits;
  WORD16    syncCorrect;
  WORD16    cntUnreliableGrossBits;
  WORD16    intl_delay;
  
  /* structs (state types) */
  fifo_state_t          rx_bits_fifo_state;
  fifo_state_t          octet_fifo_state;
  fifo_state_t          net_bits_fifo_state;
  //demod_state_t         tonedemod_state;
  // interleaver_state_t   intl_state;
  interleaver_state_t   deintl_state;
  wait_for_sync_state_t wait_state;
  viterbi_t             viterbi_state;
   
  /* vectors (not to be allocated) */
#if (NUM_MUTE_ROWS>0)
  WORD16    mutePositions[intlvB*NUM_MUTE_ROWS];
#else
  WORD16    mutePositions[1];
#endif

  /* vectors (to be allocated in init_ctm_receiver()) */
  WORD16    *waitSyncOut;
  WORD16    *deintlOut;

} rx_state_t;




/***********************************************************************/
/* init_ctm_receiver()                                                 */
/* *******************                                                 */
/* Initialization of the CTM Receiver.                                 */
/*                                                                     */
/* output vaiables:                                                    */
/* rx_state :   pointer to a variable of rx_state_t containing the     */
/*              initialized states of the receiver                     */
/***********************************************************************/

void init_ctm_receiver(rx_state_t* rx_state);

/*
 ***********************************************************************
 * Shutdown_ctm_receiver()                                             *
 * ***********************                                             *
 * Shutdown of the CTM Receiver.                                       *
 *                                                                     *
 * Input variables:                                                    *
 * rx_state :   pointer to a variable of rx_state_t containing the     *
 *              initialized states of the receiver                     *
 ***********************************************************************
*/
void Shutdown_ctm_receiver(rx_state_t* rx_state);

/*
 ***********************************************************************
 * reset_ctm_receiver()                                                *
 * ********************                                                *
 * Reset of the Cellular Text Telephone Modem receiver, state          *
 * machines and buffer pointers.                                       *
 *                                                                     *
 * Input variables:                                                    *
 * rx_state :   pointer to a variable of rx_state_t containing the     *
 *              initialized states of the receiver                     *
 ***********************************************************************
*/
void reset_ctm_receiver(rx_state_t* rx_state);


/***************************************************************************/
/* ctm_receiver()                                                          */
/* **************                                                          */
/* Runs the Cellular Text Telephone Modem Receiver for a block of          */
/* (nominally) 160 samples. Due to the internal synchronization, the       */
/* number of processed samples might vary between 156 and 164 samples.     */
/* The input of the samples and the output of the decoded characters       */
/* is handled via fifo buffers, which have to be initialized               */
/* externally before using this function (see fifo.h for details).         */
/*                                                                         */
/* input/output variables:                                                 */
/* *ptr_signal_fifo_state      fifo state for the input samples            */
/* *ptr_output_char_fifo_state fifo state for the output characters        */
/* *ptr_early_muting_required  returns whether the original audio signal   */
/*                             must not be forwarded. This is to guarantee */
/*                             that the preamble or resync sequence is     */
/*                             detected only by the first CTM device, if   */
/*                             several CTM devices are cascaded            */
/*                             subsequently.                               */
/* *rx_state                   pointer to the variable containing the      */
/*                             receiver states                             */
/***************************************************************************/

void ctm_receiver(fifo_state_t*  ptr_signal_fifo_state,
                  fifo_state_t*  ptr_output_char_fifo_state,
                  BOOL*          ptr_early_muting_required,
                  rx_state_t*    rx_state);

#endif