view src/g23m-aci/aci/plmn_decoder.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
line wrap: on
line source

/* plmn_decoder.cpp : Defines the entry point for the console application. */

#include <assert.h>
#include <stdio.h>
#include <stddef.h>
#include <stdlib.h>
#include <string.h>

#ifdef TI_PS_OP_OPN_TAB_ROMBASED
#ifndef CMH_PLMN_DECODER_C
#define CMH_PLMN_DECODER_C
#endif

#include "aci_all.h"

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

#include "aci_cmh.h"
#include "ati_cmd.h"
#include "aci_cmd.h"
#include "aci_mem.h"
#include "pcm.h"

#ifdef TI_PS_OP_OPN_TAB_ROMBASED
  #include "rom_tables.h"
#endif /* TI_PS_OP_OPN_TAB_ROMBASED */


#ifdef FAX_AND_DATA
#include "aci_fd.h"
#endif    /* of #ifdef FAX_AND_DATA */

#include "aci.h"
#include "psa.h"
#include "psa_mm.h"
#include "psa_sim.h"
#include "psa_util.h"
#include "cmh.h"



#define PLMN_LONGNAME_LOOKUP 0xff

EXTERN void  cmhSIM_getMncMccFrmPLMNsel( const UBYTE* ntry, 
                                                         SHORT* mcc, 
                                                         SHORT* mnc );

/* NHK:
 * Once the tables plmn_compressed, plmn_dict_offset and plmn_dict go to ROM, their names below should match corresponding ROM addresses
 * KSR: Moved to g23m\condat\com\src\drivers\rom_tables.c
 */

/*
+----------------------------------------------------------------------------+
| PROJECT : GSM-PS (6147)       MODULE  : MM_MM                              |
| STATE   : code                ROUTINE : cmhMM_CompLongLength               |
+----------------------------------------------------------------------------+

  PURPOSE : This function gets the compressed length of the longName
            from a compressed PLMN entry.
  
*/
LOCAL USHORT cmhMM_CompLongLength (const UBYTE *plmn_comp_entry)
{
  UBYTE length_byte;

  length_byte = *(plmn_comp_entry + 3);

  return ((length_byte >> 3) & 0x1f) + 1;
}

/*
+----------------------------------------------------------------------------+
| PROJECT : GSM-PS (6147)       MODULE  : MM_MM                              |
| STATE   : code                ROUTINE : cmhMM_CompShrtLength               |
+----------------------------------------------------------------------------+

  PURPOSE : This function gets the compressed length of the shrtName
            from a compressed PLMN entry.
  
*/
LOCAL USHORT cmhMM_CompShrtLength (const UBYTE *plmn_comp_entry)
{
  UBYTE length_byte;

  length_byte = *(plmn_comp_entry + 3);

  return ((length_byte     ) & 0x07) + 1;
}


/*
+----------------------------------------------------------------------------+
| PROJECT : GSM-PS (6147)       MODULE  : MM_MM                              |
| STATE   : code                ROUTINE : cmhMM_PlmnEntryLength              |
+----------------------------------------------------------------------------+

  PURPOSE : This function gets the length of a compressed PLMN entry.
  
*/
GLOBAL USHORT cmhMM_PlmnEntryLength (const UBYTE *plmn_comp_entry)
{
  return (4 + cmhMM_CompLongLength (plmn_comp_entry) 
            + cmhMM_CompShrtLength (plmn_comp_entry));
}


/*
+----------------------------------------------------------------------------+
| PROJECT : GSM-PS (6147)       MODULE  : MM_MM                              |
| STATE   : code                ROUTINE : cmhMM_Decompress                   |
+----------------------------------------------------------------------------+

  PURPOSE : This function decompresses a compressed string.
            If the decompressed string is the long PLMN name the longName
            parameter is NULL, when the decompressed string is the short
            PLMN name the longName parameter is the previously decompressed
            PLMN long name, as in some cases the short PLMN name consists of
            parts of the long PLMN name lookups within the decompressed long
            name will be done when advised to do so by the compressed byte 
            string.
            On success the function returns with zero, on detection of an
            internal error a negative value is returned.
 
*/
LOCAL SHORT cmhMM_Decompress (char *decomp_string, 
                              const char *longName,
                              const UBYTE *comp_string,
                              USHORT comp_length)
{
  USHORT offset;
  USHORT length;

  while (comp_length > 0)
  {
    if (*comp_string < 128)
    {
      /* GSM default alphabet. Take character 1:1 */
      *decomp_string = *comp_string;
      decomp_string++;
    }
    else if (*comp_string EQ PLMN_LONGNAME_LOOKUP)
    {
      if ((longName EQ NULL) OR (comp_length <= 1))
      {
        TRACE_ERROR ("Cannot process longName lookup");
        return -1;
      }

      /* Decoding short name. Lookup into long name */

      /* Skip PLMN_LONGNAME_LOOKUP */
      comp_string++;
      comp_length--;

      /* Get offset and length of substring in long name */
      offset = (*comp_string >> 3) & 0x1f;
      length = (*comp_string & 0x07) + 1;
      memcpy (decomp_string, longName + offset, length);
      decomp_string += length;
    }
    else
    {
      /* Dictionary lookup */

      /* Get offset of dictionary entry */
      offset = *(ptr_plmn_dict_offset + (*comp_string - 128)); 

      /* Get length of dictionary entry */
      length = *(ptr_plmn_dict_offset + (*comp_string - 128 + 1)) - offset;
      memcpy (decomp_string, ptr_plmn_dict + offset, length);
      decomp_string += length;
    }
    comp_string++;
    comp_length--;
  }
  decomp_string = '\0';
  return 0;
}


/*
+----------------------------------------------------------------------------+
| PROJECT : GSM-PS (6147)       MODULE  : MM_MM                              |
| STATE   : code                ROUTINE : cmhMM_decodePlmn                   |
+----------------------------------------------------------------------------+

  PURPOSE : This function decodes a compressed PLMN entry into a decompressed
            T_OPER_ENTRY structure. On success this function returns with 
            zero, if during decompression an internal error is detected the
            function returns with a negative value.
 
*/
GLOBAL SHORT cmhMM_decodePlmn (T_OPER_ENTRY *oper, const UBYTE *plmn_comp_entry)
{
  SHORT mcc;              /* Mobile Country Code */
  SHORT mnc;              /* Mobile Network Code */
  USHORT comp_Length;     /* Compressed string length */
  SHORT result;           /* Decompression result */
  const UBYTE *comp_ptr;  /* Compressed PLMNs pointer */

  memset (oper, 0, sizeof (T_OPER_ENTRY));

  cmhSIM_getMncMccFrmPLMNsel (plmn_comp_entry, &mcc, &mnc);
  oper->mcc = mcc;
  oper->mnc = mnc;

  if (mcc EQ -1)
    return -1; /* Got end of list, not processing further */

  /* Decompress longName */
  comp_ptr = plmn_comp_entry + 4;
  comp_Length = cmhMM_CompLongLength (plmn_comp_entry);
  result = cmhMM_Decompress (oper->longName, NULL,
                             comp_ptr, comp_Length);
  if (result < 0)
    return result;

  /* Decompress shrtName */
  comp_ptr += comp_Length;
  comp_Length = cmhMM_CompShrtLength (plmn_comp_entry);
  result = cmhMM_Decompress (oper->shrtName, oper->longName, 
                             comp_ptr, comp_Length);
  return result;
}

#endif