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  ipv4/rnet_ip_addr.h
 *
 * Riviera NET.
 *
 * IPv4 address related structures.
 * See the Readme.txt file.
 *
 * @author  Vincent Oberle (v-oberle@ti.com)
 * @version 0.1
 */

/*
 * History:
 *
 *   Date         Author        Modification
 *  --------------------------------------------------
 *  01/25/2002  Vincent Oberle    Create
 *
 * (C) Copyright 2002 by Texas Instruments Incorporated, All Rights Reserved
 */

#ifndef __RNET_IP_ADDR_H_
#define __RNET_IP_ADDR_H_

#include "rv_general.h"

#ifdef __cplusplus
extern "C"
{
#endif

/**
 * @name  IPv4 address.
 *
 * T_RNET_IP_ADDR is the IPv4 address type.
 *
 * The RNET_IP_ADDR_ANY value corresponds to any IP address.
 * The RNET_IP4_ADDR allows easy creation of IP addresses.
 */
/*@{*/
typedef UINT32 T_RNET_IP_ADDR;

#define RNET_IP_ADDR_ANY 0

#define RNET_IP4_ADDR(ipaddr, a,b,c,d) { \
  ipaddr = ((UINT32)(a & 0xff) << 24) | ((UINT32)(b & 0xff) << 16) | \
       ((UINT32)(c & 0xff) << 8) | (UINT32)(d & 0xff); \
}
/*@}*/

/**
 * Port. 16 bits.
 */
typedef UINT16 T_RNET_PORT;

#ifdef __cplusplus
}
#endif

#endif /* __RNET_IP_ADDR_H_ */