nuttx/arch/arm/src/samdl/samd_clockconfig.c

897 lines
23 KiB
C
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

/****************************************************************************
* arch/arm/src/samdl/samd_clockconfig.c
*
* Copyright (C) 2014-2015 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* References:
* 1. "Atmel SAM D20J / SAM D20G / SAM D20E ARM-Based Microcontroller
* Datasheet", 42129JSAM12/2013
* 2. "Atmel SAM D21E / SAM D21G / SAM D21J SMART ARM-Based Microcontroller
* Datasheet", Atmel-42181ESAM-D21_Datasheet02/2015
* 3. Atmel sample code for the SAMD20. This code has an ASF license
* with is compatible with the NuttX BSD license, but includes the
* provision that this code not be used in non-Atmel products. That
* sample code was used only as a reference so I believe that only the
* NuttX BSD license applies.
*
* 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. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS 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.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <stdint.h>
#include <stdbool.h>
#include <assert.h>
#include "up_arch.h"
#include "chip/samd_pm.h"
#include "chip/samd_sysctrl.h"
#include "chip/samd_gclk.h"
#include "chip/samd_nvmctrl.h"
#include "sam_fuses.h"
#include "sam_gclk.h"
#include <arch/board/board.h>
#include "samd_periphclks.h"
#include "sam_clockconfig.h"
#if defined(CONFIG_ARCH_FAMILY_SAMD20) || defined(CONFIG_ARCH_FAMILY_SAMD21)
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/****************************************************************************
* Private Types
****************************************************************************/
/****************************************************************************
* Private Data
****************************************************************************/
/* This structure describes the configuration of every enabled GCLK */
#ifdef BOARD_GCLK_ENABLE
static const struct sam_gclkconfig_s g_gclkconfig[] =
{
/* GCLK generator 0 (Main Clock) */
{
.gclk = 0,
#ifdef BOARD_GCLK0_RUN_IN_STANDBY
.runstandby = true,
#endif
#ifdef BOARD_GCLK0_OUTPUT_ENABLE
.output = true,
#endif
.prescaler = BOARD_GCLK0_PRESCALER,
.clksrc = (uint8_t)(BOARD_GCLK0_CLOCK_SOURCE >> GCLK_GENCTRL_SRC_SHIFT),
}
/* GCLK generator 1 */
#ifdef BOARD_GCLK1_ENABLE
,
{
.gclk = 1,
#ifdef BOARD_GCLK1_RUN_IN_STANDBY
.runstandby = true;
#endif
#ifdef BOARD_GCLK1_OUTPUT_ENABLE
.output = true;
#endif
.prescaler = BOARD_GCLK1_PRESCALER,
.clksrc = (uint8_t)(BOARD_GCLK1_CLOCK_SOURCE >> GCLK_GENCTRL_SRC_SHIFT),
}
#endif
/* GCLK generator 2 (RTC) */
#ifdef BOARD_GCLK2_ENABLE
,
{
.gclk = 2,
#ifdef BOARD_GCLK2_RUN_IN_STANDBY
.runstandby = true;
#endif
#ifdef BOARD_GCLK2_OUTPUT_ENABLE
.output = true;
#endif
.prescaler = BOARD_GCLK2_PRESCALER,
.clksrc = (uint8_t)(BOARD_GCLK2_CLOCK_SOURCE >> GCLK_GENCTRL_SRC_SHIFT),
}
#endif
/* GCLK generator 3 */
#ifdef BOARD_GCLK3_ENABLE
,
{
.gclk = 3,
#ifdef BOARD_GCLK3_RUN_IN_STANDBY
.runstandby = true;
#endif
#ifdef BOARD_GCLK3_OUTPUT_ENABLE
.output = true;
#endif
.prescaler = BOARD_GCLK3_PRESCALER,
.clksrc = (uint8_t)(BOARD_GCLK3_CLOCK_SOURCE >> GCLK_GENCTRL_SRC_SHIFT),
}
#endif
/* GCLK generator 4 */
#ifdef BOARD_GCLK4_ENABLE
,
{
.gclk = 4,
#ifdef BOARD_GCLK4_RUN_IN_STANDBY
.runstandby = true;
#endif
#ifdef BOARD_GCLK4_OUTPUT_ENABLE
.output = true;
#endif
.prescaler = BOARD_GCLK4_PRESCALER,
.clksrc = (uint8_t)(BOARD_GCLK4_CLOCK_SOURCE >> GCLK_GENCTRL_SRC_SHIFT),
}
#endif
/* GCLK generator 5 */
#ifdef BOARD_GCLK5_ENABLE
,
{
.gclk = 5,
#ifdef BOARD_GCLK5_RUN_IN_STANDBY
.runstandby = true;
#endif
#ifdef BOARD_GCLK5_OUTPUT_ENABLE
.output = true;
#endif
.prescaler = BOARD_GCLK5_PRESCALER,
.clksrc = (uint8_t)(BOARD_GCLK5_CLOCK_SOURCE >> GCLK_GENCTRL_SRC_SHIFT),
}
#endif
/* GCLK generator 6 */
#ifdef BOARD_GCLK6_ENABLE
,
{
.gclk = 6,
#ifdef BOARD_GCLK6_RUN_IN_STANDBY
.runstandby = true;
#endif
#ifdef BOARD_GCLK6_OUTPUT_ENABLE
.output = true;
#endif
.prescaler = BOARD_GCLK6_PRESCALER,
.clksrc = (uint8_t)(BOARD_GCLK6_CLOCK_SOURCE >> GCLK_GENCTRL_SRC_SHIFT),
}
#endif
/* GCLK generator 7 */
#ifdef BOARD_GCLK7_ENABLE
,
{
.gclk = 7,
#ifdef BOARD_GCLK7_RUN_IN_STANDBY
.runstandby = true;
#endif
#ifdef BOARD_GCLK7_OUTPUT_ENABLE
.output = true;
#endif
.prescaler = BOARD_GCLK7_PRESCALER,
.clksrc = (uint8_t)(BOARD_GCLK7_CLOCK_SOURCE >> GCLK_GENCTRL_SRC_SHIFT),
}
#endif
/* GCLK generator 8 */
#ifdef BOARD_GCLK8_ENABLE
,
{
.gclk = 8,
#ifdef BOARD_GCLK8_RUN_IN_STANDBY
.runstandby = true;
#endif
#ifdef BOARD_GCLK8_OUTPUT_ENABLE
.output = true;
#endif
.prescaler = BOARD_GCLK8_PRESCALER,
.clksrc = (uint8_t)(BOARD_GCLK8_CLOCK_SOURCE >> GCLK_GENCTRL_SRC_SHIFT),
}
#endif
};
#define NGCLKS_ENABLED (sizeof(g_gclkconfig) / sizeof(struct sam_gclkconfig_s))
#endif
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: sam_flash_waitstates
*
* Description:
* Set the FLASH wait states based on settings in the board.h header file
* Depends on:
*
* BOARD_FLASH_WAITSTATES - Number of wait states
*
* Input Parameters:
* None
*
* Returned Value:
* None
*
****************************************************************************/
static inline void sam_flash_waitstates(void)
{
uint32_t regval;
regval = getreg32(SAM_NVMCTRL_CTRLB);
regval &= ~NVMCTRL_CTRLB_RWS_MASK;
regval |= NVMCTRL_CTRLB_RWS(BOARD_FLASH_WAITSTATES);
putreg32(regval, SAM_NVMCTRL_CTRLB);
}
/****************************************************************************
* Name: sam_xosc_config
*
* Description:
* Configure XOSC based on settings in the board.h header file
* Depends on:
*
* BOARD_XOSC_ENABLE - Boolean (defined / not defined)
* BOARD_XOSC_FREQUENCY - In Hz
* BOARD_XOSC_STARTUPTIME - See SYSCTRL_XOSC_STARTUP_* definitions
* BOARD_XOSC_ISCRYSTAL - Boolean (defined / not defined)
* BOARD_XOSC_AMPGC - Boolean (defined / not defined)
* BOARD_XOSC_ONDEMAND - Boolean (defined / not defined)
* BOARD_XOSC_RUNINSTANDBY - Boolean (defined / not defined)
*
* Input Parameters:
* None
*
* Returned Value:
* None
*
****************************************************************************/
#ifdef BOARD_XOSC_ENABLE
static inline void sam_xosc_config(void)
{
uint16_t regval;
/* Configure the XOSC clock */
regval = BOARD_XOSC_STARTUPTIME
#ifdef BOARD_XOSC_ISCRYSTAL
/* XOSC is a crystal */
regval |= SYSCTRL_XOSC_XTALEN;
#endif
#ifdef BOARD_XOSC_AMPGC
/* Enable automatic gain control */
regval |= SYSCTRL_XOSC_AMPGC;
#else
/* Set gain if automatic gain control is not selected */
#if BOARD_XOSC_FREQUENCY <= 2000000
regval |= SYSCTRL_XOSC_GAIN_2MHZ;
#elif BOARD_XOSC_FREQUENCY <= 4000000
regval |= SYSCTRL_XOSC_GAIN_4MHZ;
#elif BOARD_XOSC_FREQUENCY <= 8000000
regval |= SYSCTRL_XOSC_GAIN_8MHZ;
#elif BOARD_XOSC_FREQUENCY <= 16000000
regval |= SYSCTRL_XOSC_GAIN_16MHZ;
#elif BOARD_XOSC_FREQUENCY <= 30000000
regval |= SYSCTRL_XOSC_GAIN_30MHZ;
#else
# error BOARD_XOSC_FREQUENCY out of range
#endif
#endif /* BOARD_XOSC_AMPGC */
#ifdef BOARD_XOSC_ONDEMAND
regval |= SYSCTRL_XOSC_ONDEMAND;
#endif
#ifdef BOARD_XOSC_RUNINSTANDBY
regval |= SYSCTRL_XOSC_RUNSTDBY;
#endif
putreg16(regval, SAM_SYSCTRL_XOSC);
/* Then enable the XOSC clock */
regval |= SYSCTRL_XOSC_ENABLE;
putreg16(regval, SAM_SYSCTRL_XOSC);
}
#else
# define sam_xosc_config()
#endif
/****************************************************************************
* Name: sam_xosc32k_config
*
* Description:
* Configure XOSC32K based on settings in the board.h header file.
* Depends on:
*
* BOARD_XOSC32K_ENABLE - Boolean (defined / not defined)
* BOARD_XOSC32K_FREQUENCY - In Hz
* BOARD_XOSC32K_STARTUPTIME - See SYSCTRL_XOSC32K_STARTUP_* definitions
* BOARD_XOSC32K_ISCRYSTAL - Boolean (defined / not defined)
* BOARD_XOSC32K_AAMPEN - Boolean (defined / not defined)
* BOARD_XOSC32K_EN1KHZ - Boolean (defined / not defined)
* BOARD_XOSC32K_EN32KHZ - Boolean (defined / not defined)
* BOARD_XOSC32K_ONDEMAND - Boolean (defined / not defined)
* BOARD_XOSC32K_RUNINSTANDBY - Boolean (defined / not defined)
*
* Input Parameters:
* None
*
* Returned Value:
* None
*
****************************************************************************/
#ifdef BOARD_XOSC32K_ENABLE
static inline void sam_xosc32k_config(void)
{
uint16_t regval;
/* Configure XOSC32K */
regval = BOARD_XOSC32K_STARTUPTIME
#ifdef BOARD_XOSC32K_ISCRYSTAL
regval |= SYSCTRL_XOSC32K_XTALEN;
#endif
#ifdef BOARD_XOSC32K_AAMPEN
regval |= SYSCTRL_XOSC32K_AAMPEN;
#endif
#ifdef BOARD_XOSC32K_EN1KHZ
regval |= SYSCTRL_XOSC32K_EN1K;
#endif
#ifdef BOARD_XOSC32K_EN32KHZ
regval |= SYSCTRL_XOSC32K_EN32K;
#endif
#ifdef BOARD_XOSC32K_ONDEMAND
regval |= SYSCTRL_XOSC32K_ONDEMAND;
#endif
#ifdef BOARD_XOSC32K_RUNINSTANDBY
regval |= SYSCTRL_XOSC32K_RUNSTDBY;
#endif
putreg16(regval, SAM_SYSCTRL_XOSC32K);
/* Then enable the XOSC clock */
regval |= SYSCTRL_XOSC32K_ENABLE;
putreg16(regval, SAM_SYSCTRL_XOSC32K);
}
#else
# define sam_xosc32k_config()
#endif
/****************************************************************************
* Name: sam_osc32k_config
*
* Description:
* Configure OSC32K based on settings in the board.h header file.
* Depends on:
*
* BOARD_OSC32K_ENABLE - Boolean (defined / not defined)
* BOARD_OSC32K_FREQUENCY - In Hz
* BOARD_OSC32K_STARTUPTIME - See SYSCTRL_OSC32K_STARTUP_* definitions
* BOARD_OSC32K_EN1KHZ - Boolean (defined / not defined)
* BOARD_OSC32K_EN32KHZ - Boolean (defined / not defined)
* BOARD_OSC32K_ONDEMAND - Boolean (defined / not defined)
* BOARD_OSC32K_RUNINSTANDBY - Boolean (defined / not defined)
*
* Input Parameters:
* None
*
* Returned Value:
* None
*
****************************************************************************/
#ifdef BOARD_OSC32K_ENABLE
static inline void sam_osc32k_config(void)
{
uint32_t regval;
uint32_t calib;
/* Recover OSC32K calibration data from OTP "fuse" memory */
regval = getreg32(SYSCTRL_FUSES_OSC32KCAL_ADDR);
calib = (regval & SYSCTRL_FUSES_OSC32KCAL_MASK) >> SYSCTRL_FUSES_OSC32KCAL_SHIFT;
regval = calib << SYSCTRL_OSC32K_CALIB_SHIFT;
/* Configure OSC32K */
regval |= BOARD_OSC32K_STARTUPTIME;
#ifdef BOARD_OSC32K_EN1KHZ
regval |= SYSCTRL_OSC32K_EN1K;
#endif
#ifdef BOARD_OSC32K_EN32KHZ
regval |= SYSCTRL_OSC32K_EN32K;
#endif
#ifdef BOARD_OSC32K_ONDEMAND
regval |= SYSCTRL_OSC32K_ONDEMAND;
#endif
#ifdef BOARD_OSC32K_RUNINSTANDBY
regval |= SYSCTRL_OSC32K_RUNSTDBY;
#endif
putreg32(regval, SAM_SYSCTRL_OSC32K);
/* Then enable OSC32K */
regval |= SYSCTRL_OSC32K_ENABLE;
putreg32(regval, SAM_SYSCTRL_OSC32K);
}
#else
# define sam_osc32k_config()
#endif
/****************************************************************************
* Name: sam_osc8m_config
*
* Description:
* Configure OSC8M based on settings in the board.h header file.
* Depends on:
*
* BOARD_OSC8M_PRESCALER - See SYSCTRL_OSC8M_PRESC_DIV* definitions
* BOARD_OSC8M_ONDEMAND - Boolean (defined / not defined)
* BOARD_OSC8M_RUNINSTANDBY - Boolean (defined / not defined)
*
* On any reset the synchronous clocks start to their initial state:
*
* OSC8M is enabled and divided by 8
* GCLK_MAIN uses OSC8M as source
* CPU and BUS clocks are undivided
*
* The reset state of the OSC8M register is:
*
* FFxx CCCC CCCC CCCC xxxx xxPP ORxx xxEx
* xx00 xxxx xxxx xxxx 0000 0011 1000 0010
*
* FRANGE FF Loaded from FLASH calibration at startup
* CALIB CCC...C Loaded from FLASH calibration at startup
* PRESC PP 3 = Divide by 8
* ONDEMAND O 1
* RUNSTBY R 0
* ENABLE 1 1
*
* NOTE that since we are running from OSC8M, it cannot be disable!
*
* Input Parameters:
* None
*
* Returned Value:
* None
*
****************************************************************************/
static inline void sam_osc8m_config(void)
{
uint32_t regval;
/* Configure OSC8M */
regval = getreg32(SAM_SYSCTRL_OSC8M);
regval &= ~(SYSCTRL_OSC8M_PRESC_MASK | SYSCTRL_OSC8M_ONDEMAND |
SYSCTRL_OSC8M_RUNSTDBY);
/* Select the prescaler */
regval |= (BOARD_OSC8M_PRESCALER | SYSCTRL_OSC8M_ENABLE);
#ifdef BOARD_OSC8M_ONDEMAND
/* Select on-demand oscillator controls */
regval |= SYSCTRL_OSC8M_ONDEMAND;
#endif
#ifdef BOARD_OSC8M_RUNINSTANDBY
/* The oscillator continues to run in standby sleep mode */
regval |= SYSCTRL_OSC8M_RUNSTDBY;
#endif
/* Set the OSC8M configuration */
putreg32(regval, SAM_SYSCTRL_OSC8M);
}
/****************************************************************************
* Name: sam_dfll_config
*
* Description:
* Configure the DFLL based on settings in the board.h header file.
* Depends on:
*
* BOARD_DFLL_OPENLOOP - Boolean (defined / not defined)
* BOARD_DFLL_TRACKAFTERFINELOCK - Boolean (defined / not defined)
* BOARD_DFLL_KEEPLOCKONWAKEUP - Boolean (defined / not defined)
* BOARD_DFLL_ENABLECHILLCYCLE - Boolean (defined / not defined)
* BOARD_DFLL_QUICKLOCK - Boolean (defined / not defined)
* BOARD_DFLL_ONDEMAND - Boolean (defined / not defined)
* BOARD_DFLL_COARSEVALUE - Value
* BOARD_DFLL_FINEVALUE - Value
*
* Open Loop mode only:
* BOARD_DFLL_COARSEVALUE - Value
* BOARD_DFLL_FINEVALUE - Value
*
* Closed loop mode only:
* BOARD_DFLL_SRCGCLKGEN - GCLK index
* BOARD_DFLL_MULTIPLIER - Value
* BOARD_DFLL_MAXCOARSESTEP - Value
* BOARD_DFLL_MAXFINESTEP - Value
*
* Input Parameters:
* None
*
* Returned Value:
* None
*
****************************************************************************/
#ifdef BOARD_DFLL_ENABLE
static inline void sam_dfll_config(void)
{
uint16_t control;
uint32_t regval;
/* Set up the DFLL control register */
control = SYSCTRL_DFLLCTRL_ENABLE; /* Enable the DFLL */
#ifndef BOARD_DFLL_OPENLOOP
control |= SYSCTRL_DFLLCTRL_MODE; /* Closed loop mode */
#endif
#ifndef BOARD_DFLL_TRACKAFTERFINELOCK
control |= SYSCTRL_DFLLCTRL_STABLE; /* FINE calibration fixed after a fine lock */
#endif
#ifndef BOARD_DFLL_KEEPLOCKONWAKEUP
control |= SYSCTRL_DFLLCTRL_LLAW; /* Lose lock after wake */
#endif
#ifndef BOARD_DFLL_ENABLECHILLCYCLE
control |= SYSCTRL_DFLLCTRL_CCDIS; /* Chill cycle disable */
#endif
#ifndef BOARD_DFLL_QUICKLOCK
control |= SYSCTRL_DFLLCTRL_QLDIS; /* Quick lock disable */
#endif
/* Then enable the DFLL (with ONDEMAND set to zero). */
putreg16(control, SAM_SYSCTRL_DFLLCTRL);
/* Wait for the DFLL to synchronize */
while ((getreg32(SAM_SYSCTRL_PCLKSR) & SYSCTRL_INT_DFLLRDY) == 0);
/* Set up the open loop mode multiplier register */
#ifndef BOARD_DFLL_OPENLOOP
regval = SYSCTRL_DFLLMUL_CSTEP(BOARD_DFLL_MAXCOARSESTEP) |
SYSCTRL_DFLLMUL_FSTEP(BOARD_DFLL_MAXFINESTEP) |
SYSCTRL_DFLLMUL_MUL(BOARD_DFLL_MULTIPLIER);
putreg32(regval, SAM_SYSCTRL_DFLLMUL);
#else
putreg32(0, SAM_SYSCTRL_DFLLMUL);
#endif
/* Set up the DFLL value register */
regval = SYSCTRL_DFLLVAL_COARSE(BOARD_DFLL_COARSEVALUE) |
SYSCTRL_DFLLVAL_FINE(BOARD_DFLL_FINEVALUE);
putreg32(regval, SAM_SYSCTRL_DFLLVAL);
/* Finally, set the state of the ONDEMAND bit if necessary */
#ifdef BOARD_DFLL_ONDEMAND
control |= SYSCTRL_DFLLCTRL_ONDEMAND; /* On demand control */
putreg16(control, SAM_SYSCTRL_DFLLCTRL);
#endif
}
#else
# define sam_dfll_config()
#endif
/****************************************************************************
* Name: sam_dfll_reference
*
* Description:
* Enable DFLL reference clock if in closed loop mode.
* Depends on:
*
* BOARD_DFLL_SRCGCLKGEN - GCLK index
*
* Input Parameters:
* None
*
* Returned Value:
* None
*
****************************************************************************/
#if defined(BOARD_GCLK_ENABLE) && defined(BOARD_DFLL_ENABLE) && \
!defined(BOARD_DFLL_OPENLOOP)
static inline void sam_dfll_reference(void)
{
uint16_t regval;
/* Disabled the DFLL reference clock */
regval = GCLK_CLKCTRL_ID_DFLL48M;
putreg16(regval, SAM_GCLK_CLKCTRL);
/* Wait for the clock to become disabled */
while ((getreg16(SAM_GCLK_CLKCTRL) & GCLK_CLKCTRL_CLKEN) != 0);
/* Select the configured clock generator as the source for the DFLL
* reference clock.
*
* NOTE: We could enable write lock here to prevent further modification
*/
regval = ((BOARD_DFLL_SRCGCLKGEN << GCLK_CLKCTRL_GEN_SHIFT) |
GCLK_CLKCTRL_ID_DFLL48M);
putreg16(regval, SAM_GCLK_CLKCTRL);
/* Enable the DFLL reference clock */
regval |= GCLK_CLKCTRL_CLKEN;
putreg16(regval, SAM_GCLK_CLKCTRL);
/* The CLKCTRL.CLKEN bit must be synchronized to the generic clock domain.
* CLKCTRL.CLKEN will continue to read as its previous state until the
* synchronization is complete.
*/
while ((getreg16(SAM_GCLK_CLKCTRL) & GCLK_CLKCTRL_CLKEN) == 0);
}
#else
# define sam_dfll_reference()
#endif
/****************************************************************************
* Name: sam_config_gclks
*
* Description:
* Configure GCLK(s) based on settings in the board.h header file.
* Depends on:
*
* Global enable/disable.
*
* BOARD_GCLK_ENABLE - Boolean (defined / not defined)
*
* For n=1-7:
* BOARD_GCLKn_ENABLE - Boolean (defined / not defined)
*
* For n=0-8:
* BOARD_GCLKn_RUN_IN_STANDBY - Boolean (defined / not defined)
* BOARD_GCLKn_CLOCK_SOURCE - See GCLK_GENCTRL_SRC_* definitions
* BOARD_GCLKn_PRESCALER - Value
* BOARD_GCLKn_OUTPUT_ENABLE - Boolean (defined / not defined)
*
* Input Parameters:
* None
*
* Returned Value:
* None
*
****************************************************************************/
#ifdef BOARD_GCLK_ENABLE
static inline void sam_config_gclks(void)
{
int i;
/* Turn on the GCLK interface clock */
sam_gclk_enableperiph();
/* Reset the GCLK module */
putreg8(GCLK_CTRL_SWRST, SAM_GCLK_CTRL);
/* Wait for the reset to complete */
while ((getreg8(SAM_GCLK_CTRL) & GCLK_CTRL_SWRST) != 0);
/* Configure all GCLK generators, skipping GLCK_MAIN which is configured
* below.
*/
for (i = 1; i < NGCLKS_ENABLED; i++)
{
sam_gclk_config(&g_gclkconfig[i]);
}
/* Enable DFLL reference clock if the DFLL is enabled in closed loop mode */
sam_dfll_reference();
/* Configure the GCLK_MAIN last as it may depend on the DFLL or other
* generators
*/
sam_gclk_config(&g_gclkconfig[0]);
}
#else
# define sam_config_gclks()
#endif
/****************************************************************************
* Name: sam_dividers
*
* Description:
* Setup PM main clock dividers to generate CPU, AHB, and APB clocks.
* Depends on:
*
* BOARD_CPU_DIVIDER - See PM_CPUSEL_CPUDIV_* definitions
* BOARD_CPU_FRQUENCY - In Hz
* BOARD_CPU_FAILDECT - Boolean (defined / not defined)
* BOARD_APBA_DIVIDER - See M_APBASEL_APBADIV_* definitions
* BOARD_APBA_FRQUENCY - In Hz
* BOARD_APBB_DIVIDER - See M_APBBSEL_APBBDIV_* definitions
* BOARD_APBB_FRQUENCY - In Hz
* BOARD_APBC_DIVIDER - See M_APBCSEL_APBCDIV_* definitions
* BOARD_APBC_FRQUENCY - In Hz
*
* Input Parameters:
* None
*
* Returned Value:
* None
*
****************************************************************************/
static inline void sam_dividers(void)
{
#ifdef PM_CTRL_CFDEN
uint8_t regval;
#endif
/* Set the CPU divider using the divider value from the board.h header file */
putreg8(BOARD_CPU_DIVIDER, SAM_PM_CPUSEL);
#ifdef PM_CTRL_CFDEN
/* Optionally, enable failure detection */
regval = getreg8(SAM_PM_CTRL);
#ifdef BOARD_CPU_FAILDECT
regval |= PM_CTRL_CFDEN;
#else
regval &= ~PM_CTRL_CFDEN;
#endif
putreg8(regval, SAM_PM_CTRL);
#endif
/* Set the APBA, B, and C dividers */
putreg8(BOARD_APBA_DIVIDER, SAM_PM_APBASEL);
putreg8(BOARD_APBB_DIVIDER, SAM_PM_APBBSEL);
putreg8(BOARD_APBC_DIVIDER, SAM_PM_APBCSEL);
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: sam_clockconfig
*
* Description:
* Called to establish the clock settings based on the values in board.h.
*
* Input Parameters:
* None
*
* Returned Value:
* None
*
****************************************************************************/
void sam_clockconfig(void)
{
/* Clear pending interrupt status. */
putreg32(SYSCTRL_INT_ALL, SAM_SYSCTRL_INTFLAG);
/* Set FLASH wait states */
sam_flash_waitstates();
/* Configure XOSC */
sam_xosc_config();
/* Configure XOSC32K */
sam_xosc32k_config();
/* Configure OSCK32K */
sam_osc32k_config();
/* Configure DFLL */
sam_dfll_config();
/* Configure OSC8M */
sam_osc8m_config();
/* Configure GCLK(s) */
sam_config_gclks();
/* Set CPU and BUS clock dividers */
sam_dividers();
}
#endif /* CONFIG_ARCH_FAMILY_SAMD20 || CONFIG_ARCH_FAMILY_SAMD21*/