view src/g23m-gprs/llc/llc_itxt.c @ 268:f2e52cab0a73

abb_inth.c: check all interrupt causes, not just one The original code used if - else if - else if etc constructs, thus the first detected interrupt was the only one handled. However, Iota ITSTATREG is a clear-on-read register, thus if we only handle the first detected interrupt and skip checking the others, then the other interrupts will be lost, if more than one interrupt happened to occur in one ABB interrupt handling cycle - a form of rare race condition. Change the code to check all interrupts that were read in this cycle.
author Mychaela Falconia <falcon@freecalypso.org>
date Sun, 13 Jun 2021 18:17:53 +0000
parents fa8dc04885d8
children
line wrap: on
line source

/* 
+----------------------------------------------------------------------------- 
|  Project :  
|  Modul   :  
+----------------------------------------------------------------------------- 
|  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 is part of the entity LLC and implements all 
|             functions to handles the incoming primitives as described in 
|             the SDL-documentation (T201-statemachine)
+----------------------------------------------------------------------------- 
*/ 

#ifndef LLC_ITXT_C
#define LLC_ITXT_C
#endif

#define ENTITY_LLC

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

#include "typedefs.h"   /* to get Condat data types */
#include "vsi.h"        /* to get a lot of macros */
#include "macdef.h"
#include "gprs.h"
#include "gsm.h"        /* to get a lot of macros */
#include "cnf_llc.h"    /* to get cnf-definitions */
#include "mon_llc.h"    /* to get mon-definitions */
#include "prim.h"       /* to get the definitions of used SAP and directions */
#include "llc.h"        /* to get the global entity definitions */

#include "llc_itxf.h"   /* to get local function definitions */
#include "llc_llmes.h"  /* to get LLME signal definitions */
#include "llc_irxs.h"   /* to get ITX signal definitions */


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

/*==== LOCAL VARS ===========================================================*/

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

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


/*
+------------------------------------------------------------------------------
| Function    : itx_T201_start
+------------------------------------------------------------------------------
| Description : This procedure starts timer T201 for the current SAPI. 
|
| Parameters  : 
+------------------------------------------------------------------------------
*/
GLOBAL void itx_T201_start (T_TIME length)
{
  TRACE_FUNCTION( "itx_T201_start" );

  /*
   * Start timer T201 for the current SAPI.
   */
#ifdef _SIMULATION_
  /*
   * In simulation mode, use always a timer value of 5 seconds.
   */
  vsi_t_start (VSI_CALLER
    (USHORT)(TIMER_T201_BASE + IMAP(llc_data->current_sapi)), 5000);
#else
  vsi_t_start (VSI_CALLER
    (USHORT)(TIMER_T201_BASE + IMAP(llc_data->current_sapi)), length);
#endif /* _SIMULATION_ */

  return;
} /* itx_T201_start() */


/*
+------------------------------------------------------------------------------
| Function    : itx_T201_stop
+------------------------------------------------------------------------------
| Description : This procedure stops timer T201 for the current SAPI. 
|
| Parameters  : 
+------------------------------------------------------------------------------
*/
GLOBAL void itx_T201_stop (void)
{
  TRACE_FUNCTION( "itx_T201_stop" );

  /*
   * Stops timer T201 for the current SAPI.
   */
  vsi_t_stop (VSI_CALLER 
    (USHORT)(TIMER_T201_BASE + IMAP(llc_data->current_sapi)));

  return;
} /* itx_T201_stop() */



/*
+------------------------------------------------------------------------------
| Function    : itx_timer_t201
+------------------------------------------------------------------------------
| Description : Handles expiry of timer T201. This function is called from
|               pei_timeout().
|
| Parameters  : sapi - indicates the SAPI for which the timer has expired
|
+------------------------------------------------------------------------------
*/
GLOBAL void itx_timer_t201 (UBYTE sapi)
{ 
  TRACE_FUNCTION( "itx_timer_t201" );
  
  TRACE_0_INFO("T201 EXPIRED" );

  SWITCH_LLC (sapi);

  switch (GET_STATE(ITX))
  {
    case ITX_ABM:
      /*
       * If a frame is associated with T201, increment the 
       * retransmission counter and if below N200, restart 
       * T201. Else initate the ABM-Re-Establish procedure.
       */
      if ( llc_data->itx->t201_entry != NULL)
      {
        llc_data->itx->t201_entry->status = IQ_RETR_FRAME;

        if ( llc_data->itx->t201_entry->n_retr <= *(llc_data->n200) )
        {
          TIMERSTART (T201, llc_data->t200->length);
          itx_send_next_frame (ABIT_SET_REQ);
        }
        else
        {
          /*
           * Initate ABM Re-Establish procedure. The state change 
           * will be done by the reestablish procedure later.
           */
          sig_itx_llme_reest_ind (LLGMM_ERRCS_ACK_NO_PEER_RES_REEST);
        }
      }
      /* SET_STATE (ITX, SAME_STATE); */
      break;

    case ITX_ABM_PEER_BUSY:
      /*
       * If the Peer busy retransmission counter is below N200
       * restart T201 and send an appropriated S frame. Else
       * initate the ABM-Re-Establish procedure.
       */
      if ( llc_data->itx->n_pb_retr < *(llc_data->n200) )
      {
        TIMERSTART (T201, llc_data->t200->length);
        sig_itx_irx_s_frame_req (ABIT_SET_REQ); 
        llc_data->itx->n_pb_retr += 1;
      }
      else
      {
        sig_itx_llme_reest_ind (LLGMM_ERRCS_PEER_BUSY_REEST);
      }
      /* SET_STATE (ITX, SAME_STATE); */
      break;

    default:
      TRACE_ERROR( "T201 unexpected" );
      break;
  }

} /* itx_timer_t201() */