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.

/**
 * @file  rnet_env.h
 *
 * Riviera NET.
 *
 * Declarations of the Riviera Generic Functions
 *
 * @author  Vincent Oberle (v-oberle@ti.com)
 * @version 0.1
 */

/*
 * History:
 *
 *  Date         Author        Modification
 *  -------------------------------------------------------------------
 *  01/29/2002  Vincent Oberle    Create
 *
 * (C) Copyright 2002 by Texas Instruments Incorporated, All Rights Reserved
 */

#ifndef __RNET_ENV_H_
#define __RNET_ENV_H_

#include "rvm_gen.h" /* Generic RVM types and functions. */
#include "rvf_pool_size.h" /* Stack & Memory Bank sizes definitions */

/**
 * @name Memory bank size and stack size
 *
 * Memory bank size and watermark.
 * Wished task stack in bytes.
 */
/*@{*/
#ifdef RVF_RNET_MB1_SIZE
#define RNET_MB_PRIM_SIZE RVF_RNET_MB1_SIZE
#else
#define RNET_MB_PRIM_SIZE 500
#endif
#define RNET_MB_PRIM_WATERMARK (RNET_MB_PRIM_SIZE - 100)
/*@}*/

/**
 * @name Generic functions
 *
 * Generic functions declarations needed for a type 2 SWE
 * (Group Member SWE).
 */
/*@{*/
T_RVM_RETURN rnet_get_info (T_RVM_INFO_SWE *info_swe);

T_RVM_RETURN rnet_set_info (T_RVF_ADDR_ID addr_id,
              T_RV_RETURN_PATH return_path[],
              T_RVF_MB_ID bk_id_table[],
              T_RVM_CB_FUNC call_back_error_ft);

T_RVM_RETURN rnet_init (void);
T_RVM_RETURN rnet_start (void);

T_RVM_RETURN rnet_stop (void);
T_RVM_RETURN rnet_kill (void);
/*@}*/

#endif /* __RNET_ENV_H_ */