portable/ThirdParty/XCC/Xtensa/xtensa_init.c

/*
 * Copyright (c) 2015-2019 Cadence Design Systems, Inc.
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * The above copyright notice and this permission notice shall be included
 * in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
 * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
 * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

/*
 * XTENSA INITIALIZATION ROUTINES CODED IN C
 *
 * This file contains miscellaneous Xtensa RTOS-generic initialization functions
 * that are implemented in C.
 */


#ifdef XT_BOARD
    #include    <xtensa/xtbsp.h>
#endif

#include    "xtensa_rtos.h"

#ifdef XT_RTOS_TIMER_INT

    unsigned _xt_tick_divisor = 0; /* cached number of cycles per tick */

/*
 * Compute and initialize at run-time the tick divisor (the number of
 * processor clock cycles in an RTOS tick, used to set the tick timer).
 * Called when the processor clock frequency is not known at compile-time.
 */
    void _xt_tick_divisor_init( void )
    {
        #ifdef XT_CLOCK_FREQ
            _xt_tick_divisor     = ( XT_CLOCK_FREQ / XT_TICK_PER_SEC );
        #else
            #ifdef XT_BOARD
                _xt_tick_divisor = xtbsp_clock_freq_hz() / XT_TICK_PER_SEC;
            #else
            #error "No way to obtain processor clock frequency"
            #endif /* XT_BOARD */
        #endif /* XT_CLOCK_FREQ */
    }

#endif /* XT_RTOS_TIMER_INT */