/** * \file * * \brief System clock management * * Copyright (c) 2010-2015 Atmel Corporation. All rights reserved. * * \asf_license_start * * \page License * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * 1. Redistributions of source code must retain the above copyright notice, * this list of conditions and the following disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * * 3. The name of Atmel may not be used to endorse or promote products derived * from this software without specific prior written permission. * * 4. This software may only be redistributed and used in connection with an * Atmel microcontroller product. * * THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR IMPLIED * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE * EXPRESSLY AND SPECIFICALLY DISCLAIMED. IN NO EVENT SHALL ATMEL BE LIABLE FOR * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. * * \asf_license_stop * */ /* * Support and FAQ: visit Atmel Support */ #ifndef SYSCLK_H_INCLUDED #define SYSCLK_H_INCLUDED #include "parts.h" #include "conf_clock.h" #if SAM3S # include "sam3s/sysclk.h" #elif SAM3U # include "sam3u/sysclk.h" #elif SAM3N # include "sam3n/sysclk.h" #elif SAM3XA # include "sam3x/sysclk.h" #elif SAM4S # include "sam4s/sysclk.h" #elif SAM4E # include "sam4e/sysclk.h" #elif SAM4C # include "sam4c/sysclk.h" #elif SAM4CM # include "sam4cm/sysclk.h" #elif SAM4CP # include "sam4cp/sysclk.h" #elif SAM4L # include "sam4l/sysclk.h" #elif SAM4N # include "sam4n/sysclk.h" #elif SAMG # include "samg/sysclk.h" #elif SAMV71 # include "samv71/sysclk.h" #elif SAMV70 # include "samv70/sysclk.h" #elif SAME70 # include "same70/sysclk.h" #elif SAMS70 # include "sams70/sysclk.h" #elif (UC3A0 || UC3A1) # include "uc3a0_a1/sysclk.h" #elif UC3A3 # include "uc3a3_a4/sysclk.h" #elif UC3B # include "uc3b0_b1/sysclk.h" #elif UC3C # include "uc3c/sysclk.h" #elif UC3D # include "uc3d/sysclk.h" #elif UC3L # include "uc3l/sysclk.h" #elif XMEGA # include "xmega/sysclk.h" #elif MEGA # include "mega/sysclk.h" #else # error Unsupported chip type #endif /** * \defgroup clk_group Clock Management */ /** * \ingroup clk_group * \defgroup sysclk_group System Clock Management * * See \ref sysclk_quickstart. * * The sysclk API covers the system clock and all * clocks derived from it. The system clock is a chip-internal clock on * which all synchronous clocks, i.e. CPU and bus/peripheral * clocks, are based. The system clock is typically generated from one * of a variety of sources, which may include crystal and RC oscillators * as well as PLLs. The clocks derived from the system clock are * sometimes also known as synchronous clocks, since they * always run synchronously with respect to each other, as opposed to * generic clocks which may run from different oscillators or * PLLs. * * Most applications should simply call sysclk_init() to initialize * everything related to the system clock and its source (oscillator, * PLL or DFLL), and leave it at that. More advanced applications, and * platform-specific drivers, may require additional services from the * clock system, some of which may be platform-specific. * * \section sysclk_group_platform Platform Dependencies * * The sysclk API is partially chip- or platform-specific. While all * platforms provide mostly the same functionality, there are some * variations around how different bus types and clock tree structures * are handled. * * The following functions are available on all platforms with the same * parameters and functionality. These functions may be called freely by * portable applications, drivers and services: * - sysclk_init() * - sysclk_set_source() * - sysclk_get_main_hz() * - sysclk_get_cpu_hz() * - sysclk_get_peripheral_bus_hz() * * The following functions are available on all platforms, but there may * be variations in the function signature (i.e. parameters) and * behavior. These functions are typically called by platform-specific * parts of drivers, and applications that aren't intended to be * portable: * - sysclk_enable_peripheral_clock() * - sysclk_disable_peripheral_clock() * - sysclk_enable_module() * - sysclk_disable_module() * - sysclk_module_is_enabled() * - sysclk_set_prescalers() * * All other functions should be considered platform-specific. * Enabling/disabling clocks to specific peripherals as well as * determining the speed of these clocks should be done by calling * functions provided by the driver for that peripheral. * * @{ */ //! \name System Clock Initialization //@{ /** * \fn void sysclk_init(void) * \brief Initialize the synchronous clock system. * * This function will initialize the system clock and its source. This * includes: * - Mask all synchronous clocks except for any clocks which are * essential for normal operation (for example internal memory * clocks). * - Set up the system clock prescalers as specified by the * application's configuration file. * - Enable the clock source specified by the application's * configuration file (oscillator or PLL) and wait for it to become * stable. * - Set the main system clock source to the clock specified by the * application's configuration file. * * Since all non-essential peripheral clocks are initially disabled, it * is the responsibility of the peripheral driver to re-enable any * clocks that are needed for normal operation. */ //@} //! @} #endif /* SYSCLK_H_INCLUDED */