view src/cs/services/lls/lls_env.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 4e78acac3d88
children
line wrap: on
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/**
 * @file   lls_env.c
 *
 * Coding of the Riviera Generic Functions 
 *
 * @author   Laurent Sollier (l-sollier@ti.com)
 * @version 0.1
 */

/*
 * History:
 *
 *   Date          Author       Modification
 *  ----------------------------------------
 *  03/12/2002     L Sollier    Create
 *
 *
 * (C) Copyright 2002 by Texas Instruments Incorporated, All Rights Reserved
 */

#include "lls/lls_env.h"
#include "lls/lls_i.h"

#include "rvm/rvm_use_id_list.h"

#include <string.h>


/**
 * Pointer on the structure gathering all the global variables
 * used by LLS instance.
 */
T_LLS_ENV_CTRL_BLK* lls_env_ctrl_blk = NULL;


/**
 * @name Riviera generic functions implementation
 *
 */
/*@{*/

/**
 * function: lls_get_info
 */
T_RVM_RETURN lls_get_info(T_RVM_INFO_SWE* swe_info)
{
   /* SWE info */
   swe_info->swe_type = RVM_SWE_TYPE_1;
   swe_info->type_info.type1.swe_use_id = LLS_USE_ID;

   memcpy( swe_info->type_info.type1.swe_name, "LLS", sizeof("LLS") );

   /* Set the return path */
   swe_info->type_info.type1.return_path.callback_func   = NULL;
   swe_info->type_info.type1.return_path.addr_id         = 0;


   /* memory bank info */
   swe_info->type_info.type1.nb_mem_bank = 1;

   memcpy ((UINT8 *)    swe_info->type_info.type1.mem_bank[0].bank_name, "LLS_PRIM", 9);
   swe_info->type_info.type1.mem_bank[0].initial_params.size          = LLS_MB_PRIM_SIZE;
   swe_info->type_info.type1.mem_bank[0].initial_params.watermark     = LLS_MB_PRIM_WATERMARK;

   /* linked SWE info */
   /* this SWE does not require any SWE to run */
   swe_info->type_info.type1.nb_linked_swe = 1;
   swe_info->type_info.type1.linked_swe_id[0] = SPI_USE_ID;

   /* generic functions */
   swe_info->type_info.type1.set_info = lls_set_info;
   swe_info->type_info.type1.init     = lls_init;
   swe_info->type_info.type1.start    = lls_start;
   swe_info->type_info.type1.stop     = lls_stop;
   swe_info->type_info.type1.kill     = lls_kill;

   return RVM_OK;
}


/**
 * function: lls_set_info
 */
T_RVM_RETURN lls_set_info (T_RVF_ADDR_ID   addr_id, 
                           T_RV_RETURN     return_path[], 
                           T_RVF_MB_ID     bk_id[],
                           T_RVM_RETURN   (*rvm_error_ft)(T_RVM_NAME       swe_name,
                                                          T_RVM_RETURN     error_cause,
                                                          T_RVM_ERROR_TYPE error_type,
                                                          T_RVM_STRING     error_msg))
{
   /* Create instance gathering all the variable used by LLS instance */
   if (rvf_get_buf(bk_id[0], 
                  sizeof(T_LLS_ENV_CTRL_BLK),
                  (T_RVF_BUFFER**)&lls_env_ctrl_blk) != RVF_GREEN)
   {
      /* The environemnt will cancel the LLS instance creation. */
      return RVM_MEMORY_ERR;
   }

   /* Store the pointer to the error function */
   lls_env_ctrl_blk->error_ft = rvm_error_ft ;
   /* Store the mem bank id. */
   lls_env_ctrl_blk->prim_id = bk_id[0];
   lls_env_ctrl_blk->swe_is_initialized = FALSE;

   /* return_path of linked SWE -> not used */
   return RVM_OK;
}


/**
 * function: lls_init
 */
T_RVM_RETURN lls_init(void)
{
   if (lls_env_ctrl_blk != 0)
      lls_env_ctrl_blk->swe_is_initialized = TRUE;
   else
      return RV_INTERNAL_ERR;

   if (lls_initialize() != RV_OK)
      return RV_INTERNAL_ERR;

   return RV_OK;
}


/**
 * function: lls_start
 */
T_RVM_RETURN lls_start(void)
{
   return RV_OK;
}


/**
 * function: lls_stop
 */
T_RVM_RETURN lls_stop(void)
{

   return RVM_OK;
}


/**
 * function: lls_kill
 */
T_RVM_RETURN lls_kill (void)
{
   /*
    * DO NOT SEND MESSAGES
    */
   rvf_free_buf(lls_env_ctrl_blk);

   lls_kill_service();

   return RVM_OK;
}


/*@}*/