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/*
* Copyright (c) 2020 Raspberry Pi (Trading) Ltd.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#ifndef _HARDWARE_CLOCKS_H
#define _HARDWARE_CLOCKS_H
#include "pico.h"
#include "hardware/structs/clocks.h"
#ifdef __cplusplus
extern "C" {
#endif
/** \file hardware/clocks.h
* \defgroup hardware_clocks hardware_clocks
*
* Clock Management API
*
* This API provides a high level interface to the clock functions.
*
* The clocks block provides independent clocks to on-chip and external components. It takes inputs from a variety of clock
* sources allowing the user to trade off performance against cost, board area and power consumption. From these sources
* it uses multiple clock generators to provide the required clocks. This architecture allows the user flexibility to start and
* stop clocks independently and to vary some clock frequencies whilst maintaining others at their optimum frequencies
*
* Please refer to the datasheet for more details on the RP2040 clocks.
*
* The clock source depends on which clock you are attempting to configure. The first table below shows main clock sources. If
* you are not setting the Reference clock or the System clock, or you are specifying that one of those two will be using an auxiliary
* clock source, then you will need to use one of the entries from the subsequent tables.
*
* **Main Clock Sources**
*
* Source | Reference Clock | System Clock
* -------|-----------------|---------
* ROSC | CLOCKS_CLK_REF_CTRL_SRC_VALUE_ROSC_CLKSRC_PH | |
* Auxiliary | CLOCKS_CLK_REF_CTRL_SRC_VALUE_CLKSRC_CLK_REF_AUX | CLOCKS_CLK_SYS_CTRL_SRC_VALUE_CLKSRC_CLK_SYS_AUX
* XOSC | CLOCKS_CLK_REF_CTRL_SRC_VALUE_XOSC_CLKSRC | |
* Reference | | CLOCKS_CLK_SYS_CTRL_SRC_VALUE_CLK_REF
*
* **Auxiliary Clock Sources**
*
* The auxiliary clock sources available for use in the configure function depend on which clock is being configured. The following table
* describes the available values that can be used. Note that for clk_gpout[x], x can be 0-3.
*
*
* Aux Source | clk_gpout[x] | clk_ref | clk_sys
* -----------|------------|---------|--------
* System PLL | CLOCKS_CLK_GPOUTx_CTRL_AUXSRC_VALUE_CLKSRC_PLL_SYS | | CLOCKS_CLK_SYS_CTRL_AUXSRC_VALUE_CLKSRC_PLL_SYS
* GPIO in 0 | CLOCKS_CLK_GPOUTx_CTRL_AUXSRC_VALUE_CLKSRC_GPIN0 | CLOCKS_CLK_REF_CTRL_AUXSRC_VALUE_CLKSRC_GPIN0 | CLOCKS_CLK_SYS_CTRL_AUXSRC_VALUE_CLKSRC_GPIN0
* GPIO in 1 | CLOCKS_CLK_GPOUTx_CTRL_AUXSRC_VALUE_CLKSRC_GPIN1 | CLOCKS_CLK_REF_CTRL_AUXSRC_VALUE_CLKSRC_GPIN1 | CLOCKS_CLK_SYS_CTRL_AUXSRC_VALUE_CLKSRC_GPIN1
* USB PLL | CLOCKS_CLK_GPOUTx_CTRL_AUXSRC_VALUE_CLKSRC_PLL_USB | CLOCKS_CLK_REF_CTRL_AUXSRC_VALUE_CLKSRC_PLL_USB| CLOCKS_CLK_SYS_CTRL_AUXSRC_VALUE_CLKSRC_PLL_USB
* ROSC | CLOCKS_CLK_GPOUTx_CTRL_AUXSRC_VALUE_ROSC_CLKSRC | | CLOCKS_CLK_SYS_CTRL_AUXSRC_VALUE_ROSC_CLKSRC
* XOSC | CLOCKS_CLK_GPOUTx_CTRL_AUXSRC_VALUE_XOSC_CLKSRC | | CLOCKS_CLK_SYS_CTRL_AUXSRC_VALUE_ROSC_CLKSRC
* System clock | CLOCKS_CLK_GPOUTx_CTRL_AUXSRC_VALUE_CLK_SYS | | |
* USB Clock | CLOCKS_CLK_GPOUTx_CTRL_AUXSRC_VALUE_CLK_USB | | |
* ADC clock | CLOCKS_CLK_GPOUTx_CTRL_AUXSRC_VALUE_CLK_ADC | | |
* RTC Clock | CLOCKS_CLK_GPOUTx_CTRL_AUXSRC_VALUE_CLK_RTC | | |
* Ref clock | CLOCKS_CLK_GPOUTx_CTRL_AUXSRC_VALUE_CLK_REF | | |
*
* Aux Source | clk_peri | clk_usb | clk_adc
* -----------|-----------|---------|--------
* System PLL | CLOCKS_CLK_PERI_CTRL_AUXSRC_VALUE_CLKSRC_PLL_SYS | CLOCKS_CLK_USB_CTRL_AUXSRC_VALUE_CLKSRC_PLL_SYS | CLOCKS_CLK_ADC_CTRL_AUXSRC_VALUE_CLKSRC_PLL_SYS
* GPIO in 0 | CLOCKS_CLK_PERI_CTRL_AUXSRC_VALUE_CLKSRC_GPIN0 | CLOCKS_CLK_USB_CTRL_AUXSRC_VALUE_CLKSRC_GPIN0 | CLOCKS_CLK_ADC_CTRL_AUXSRC_VALUE_CLKSRC_GPIN0
* GPIO in 1 | CLOCKS_CLK_PERI_CTRL_AUXSRC_VALUE_CLKSRC_GPIN1 | CLOCKS_CLK_USB_CTRL_AUXSRC_VALUE_CLKSRC_GPIN1 | CLOCKS_CLK_ADC_CTRL_AUXSRC_VALUE_CLKSRC_GPIN1
* USB PLL | CLOCKS_CLK_PERI_CTRL_AUXSRC_VALUE_CLKSRC_PLL_USB | CLOCKS_CLK_USB_CTRL_AUXSRC_VALUE_CLKSRC_PLL_USB | CLOCKS_CLK_ADC_CTRL_AUXSRC_VALUE_CLKSRC_PLL_USB
* ROSC | CLOCKS_CLK_PERI_CTRL_AUXSRC_VALUE_ROSC_CLKSRC_PH | CLOCKS_CLK_USB_CTRL_AUXSRC_VALUE_ROSC_CLKSRC_PH | CLOCKS_CLK_ADC_CTRL_AUXSRC_VALUE_ROSC_CLKSRC_PH
* XOSC | CLOCKS_CLK_PERI_CTRL_AUXSRC_VALUE_XOSC_CLKSRC | CLOCKS_CLK_USB_CTRL_AUXSRC_VALUE_XOSC_CLKSRC | CLOCKS_CLK_ADC_CTRL_AUXSRC_VALUE_XOSC_CLKSRC
* System clock | CLOCKS_CLK_PERI_CTRL_AUXSRC_VALUE_CLK_SYS | | |
*
* Aux Source | clk_rtc
* -----------|----------
* System PLL | CLOCKS_CLK_RTC_CTRL_AUXSRC_VALUE_CLKSRC_PLL_SYS
* GPIO in 0 | CLOCKS_CLK_RTC_CTRL_AUXSRC_VALUE_CLKSRC_GPIN0
* GPIO in 1 | CLOCKS_CLK_RTC_CTRL_AUXSRC_VALUE_CLKSRC_GPIN1
* USB PLL | CLOCKS_CLK_RTC_CTRL_AUXSRC_VALUE_CLKSRC_PLL_USB
* ROSC | CLOCKS_CLK_RTC_CTRL_AUXSRC_VALUE_ROSC_CLKSRC_PH
* XOSC | CLOCKS_CLK_RTC_CTRL_AUXSRC_VALUE_XOSC_CLKSRC
*
* \section clock_example Example
* \addtogroup hardware_clocks
* \include hello_48MHz.c
*/
#define KHZ 1000
#define MHZ 1000000
/// \tag::pll_settings[]
//
// There are two PLLs in RP2040:
// 1. The 'SYS PLL' generates the 125MHz system clock, the frequency is defined by `SYS_CLK_KHZ`.
// 2. The 'USB PLL' generates the 48MHz USB clock, the frequency is defined by `USB_CLK_KHZ`.
//
// The two PLLs use the crystal oscillator output directly as their reference frequency input; the PLLs reference
// frequency cannot be reduced by the dividers present in the clocks block. The crystal frequency is defined by `XOSC_KHZ` or
// `XOSC_MHZ`.
//
// The system's default definitions are correct for the above frequencies with a 12MHz
// crystal frequency. If different frequencies are required, these must be defined in
// the board configuration file together with the revised PLL settings
// Use `vcocalc.py` to check and calculate new PLL settings if you change any of these frequencies.
//
// Default PLL configuration:
// REF FBDIV VCO POSTDIV
// PLL SYS: 12 / 1 = 12MHz * 125 = 1500MHz / 6 / 2 = 125MHz
// PLL USB: 12 / 1 = 12MHz * 100 = 1200MHz / 5 / 5 = 48MHz
/// \end::pll_settings[]
// PICO_CONFIG: PLL_COMMON_REFDIV, PLL reference divider setting - used for both PLLs, type=int, default=1, advanced=true, group=hardware_clocks
#ifndef PLL_COMMON_REFDIV
#define PLL_COMMON_REFDIV 1
#endif
#if (SYS_CLK_KHZ == 125000) && (XOSC_KHZ == 12000) && (PLL_COMMON_REFDIV == 1)
// PLL settings for standard 125 MHz system clock.
// PICO_CONFIG: PLL_SYS_VCO_FREQ_KHZ, System clock PLL frequency, type=int, default=1500 * KHZ, advanced=true, group=hardware_clocks
#ifndef PLL_SYS_VCO_FREQ_KHZ
#define PLL_SYS_VCO_FREQ_KHZ (1500 * KHZ)
#endif
// PICO_CONFIG: PLL_SYS_POSTDIV1, System clock PLL post divider 1 setting, type=int, default=6, advanced=true, group=hardware_clocks
#ifndef PLL_SYS_POSTDIV1
#define PLL_SYS_POSTDIV1 6
#endif
// PICO_CONFIG: PLL_SYS_POSTDIV2, System clock PLL post divider 2 setting, type=int, default=2, advanced=true, group=hardware_clocks
#ifndef PLL_SYS_POSTDIV2
#define PLL_SYS_POSTDIV2 2
#endif
#endif // SYS_CLK_KHZ == 125000 && XOSC_KHZ == 12000 && PLL_COMMON_REFDIV == 1
#if !defined(PLL_SYS_VCO_FREQ_KHZ) || !defined(PLL_SYS_POSTDIV1) || !defined(PLL_SYS_POSTDIV2)
#error PLL_SYS_VCO_FREQ_KHZ, PLL_SYS_POSTDIV1 and PLL_SYS_POSTDIV2 must all be specified when using custom clock setup
#endif
#if (USB_CLK_KHZ == 48000) && (XOSC_KHZ == 12000) && (PLL_COMMON_REFDIV == 1)
// PLL settings for a USB clock of 48MHz.
// PICO_CONFIG: PLL_USB_VCO_FREQ_KHZ, USB clock PLL frequency, type=int, default=1200 * KHZ, advanced=true, group=hardware_clocks
#ifndef PLL_USB_VCO_FREQ_KHZ
#define PLL_USB_VCO_FREQ_KHZ (1200 * KHZ)
#endif
// PICO_CONFIG: PLL_USB_POSTDIV1, USB clock PLL post divider 1 setting, type=int, default=5, advanced=true, group=hardware_clocks
#ifndef PLL_USB_POSTDIV1
#define PLL_USB_POSTDIV1 5
#endif
// PICO_CONFIG: PLL_USB_POSTDIV2, USB clock PLL post divider 2 setting, type=int, default=5, advanced=true, group=hardware_clocks
#ifndef PLL_USB_POSTDIV2
#define PLL_USB_POSTDIV2 5
#endif
#endif // USB_CLK_KHZ == 48000 && XOSC_KHZ == 12000 && PLL_COMMON_REFDIV == 1
#if !defined(PLL_USB_VCO_FREQ_KHZ) || !defined(PLL_USB_POSTDIV1) || !defined(PLL_USB_POSTDIV2)
#error PLL_USB_VCO_FREQ_KHZ, PLL_USB_POSTDIV1 and PLL_USB_POSTDIV2 must all be specified when using custom clock setup.
#endif
// PICO_CONFIG: PARAM_ASSERTIONS_ENABLED_CLOCKS, Enable/disable assertions in the clocks module, type=bool, default=0, group=hardware_clocks
#ifndef PARAM_ASSERTIONS_ENABLED_CLOCKS
#define PARAM_ASSERTIONS_ENABLED_CLOCKS 0
#endif
/*! \brief Initialise the clock hardware
* \ingroup hardware_clocks
*
* Must be called before any other clock function.
*/
void clocks_init(void);
/*! \brief Configure the specified clock
* \ingroup hardware_clocks
*
* See the tables in the description for details on the possible values for clock sources.
*
* \param clk_index The clock to configure
* \param src The main clock source, can be 0.
* \param auxsrc The auxiliary clock source, which depends on which clock is being set. Can be 0
* \param src_freq Frequency of the input clock source
* \param freq Requested frequency
*/
bool clock_configure(enum clock_index clk_index, uint32_t src, uint32_t auxsrc, uint32_t src_freq, uint32_t freq);
/*! \brief Stop the specified clock
* \ingroup hardware_clocks
*
* \param clk_index The clock to stop
*/
void clock_stop(enum clock_index clk_index);
/*! \brief Get the current frequency of the specified clock
* \ingroup hardware_clocks
*
* \param clk_index Clock
* \return Clock frequency in Hz
*/
uint32_t clock_get_hz(enum clock_index clk_index);
/*! \brief Measure a clocks frequency using the Frequency counter.
* \ingroup hardware_clocks
*
* Uses the inbuilt frequency counter to measure the specified clocks frequency.
* Currently, this function is accurate to +-1KHz. See the datasheet for more details.
*/
uint32_t frequency_count_khz(uint src);
/*! \brief Set the "current frequency" of the clock as reported by clock_get_hz without actually changing the clock
* \ingroup hardware_clocks
*
* \see clock_get_hz()
*/
void clock_set_reported_hz(enum clock_index clk_index, uint hz);
/// \tag::frequency_count_mhz[]
static inline float frequency_count_mhz(uint src) {
return ((float) (frequency_count_khz(src))) / KHZ;
}
/// \end::frequency_count_mhz[]
/*! \brief Resus callback function type.
* \ingroup hardware_clocks
*
* User provided callback for a resus event (when clk_sys is stopped by the programmer and is restarted for them).
*/
typedef void (*resus_callback_t)(void);
/*! \brief Enable the resus function. Restarts clk_sys if it is accidentally stopped.
* \ingroup hardware_clocks
*
* The resuscitate function will restart the system clock if it falls below a certain speed (or stops). This
* could happen if the clock source the system clock is running from stops. For example if a PLL is stopped.
*
* \param resus_callback a function pointer provided by the user to call if a resus event happens.
*/
void clocks_enable_resus(resus_callback_t resus_callback);
/*! \brief Output an optionally divided clock to the specified gpio pin.
* \ingroup hardware_clocks
*
* \param gpio The GPIO pin to output the clock to. Valid GPIOs are: 21, 23, 24, 25. These GPIOs are connected to the GPOUT0-3 clock generators.
* \param src The source clock. See the register field CLOCKS_CLK_GPOUT0_CTRL_AUXSRC for a full list. The list is the same for each GPOUT clock generator.
* \param div_int The integer part of the value to divide the source clock by. This is useful to not overwhelm the GPIO pin with a fast clock. this is in range of 1..2^24-1.
* \param div_frac The fractional part of the value to divide the source clock by. This is in range of 0..255 (/256).
*/
void clock_gpio_init_int_frac(uint gpio, uint src, uint32_t div_int, uint8_t div_frac);
/*! \brief Output an optionally divided clock to the specified gpio pin.
* \ingroup hardware_clocks
*
* \param gpio The GPIO pin to output the clock to. Valid GPIOs are: 21, 23, 24, 25. These GPIOs are connected to the GPOUT0-3 clock generators.
* \param src The source clock. See the register field CLOCKS_CLK_GPOUT0_CTRL_AUXSRC for a full list. The list is the same for each GPOUT clock generator.
* \param div The float amount to divide the source clock by. This is useful to not overwhelm the GPIO pin with a fast clock.
*/
static inline void clock_gpio_init(uint gpio, uint src, float div)
{
uint div_int = (uint)div;
uint8_t frac = (uint8_t)((div - (float)div_int) * (1u << CLOCKS_CLK_GPOUT0_DIV_INT_LSB));
clock_gpio_init_int_frac(gpio, src, div_int, frac);
}
/*! \brief Configure a clock to come from a gpio input
* \ingroup hardware_clocks
*
* \param clk_index The clock to configure
* \param gpio The GPIO pin to run the clock from. Valid GPIOs are: 20 and 22.
* \param src_freq Frequency of the input clock source
* \param freq Requested frequency
*/
bool clock_configure_gpin(enum clock_index clk_index, uint gpio, uint32_t src_freq, uint32_t freq);
#ifdef __cplusplus
}
#endif
#endif