platform/linux-generic/arch/aarch64/odp_global_time.c


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/* Copyright (c) 2015-2018, Linaro Limited
 * All rights reserved.
 *
 * SPDX-License-Identifier:     BSD-3-Clause
 */

#include <odp/api/abi/cpu_time.h>

int _odp_cpu_has_global_time(void)
{
	uint64_t hz = _odp_cpu_global_time_freq();

	/*
	 * The system counter portion of the architected timer must
	 * provide a uniform view of system time to all processing
	 * elements in the system. This should hold true even for
	 * heterogeneous SoCs.
	 *
	 * Determine whether the system has 'global time' by checking
	 * whether a read of the architected timer frequency sys reg
	 * returns a sane value. Sane is considered to be within
	 * 1MHz and 6GHz (1us and .1667ns period).
	 */
	return hz >= 1000000 && hz <= 6000000000;
}