543 lines
13 KiB
C
543 lines
13 KiB
C
/** @defgroup rcc_file RCC peripheral API
|
|
*
|
|
* @ingroup peripheral_apis
|
|
*
|
|
* @brief <b>libopencm3 STM32L0xx Reset and Clock Control</b>
|
|
*
|
|
* @version 1.0.0
|
|
*
|
|
* @date November 2014
|
|
*
|
|
* This library supports the Reset and Clock Control System in the STM32F0xx
|
|
* series of ARM Cortex Microcontrollers by ST Microelectronics.
|
|
*
|
|
* LGPL License Terms @ref lgpl_license
|
|
*/
|
|
/*
|
|
* This file is part of the libopencm3 project.
|
|
*
|
|
* Copyright (C) 2014 Karl Palsson <karlp@tweak.net.au>
|
|
*
|
|
* This library is free software: you can redistribute it and/or modify
|
|
* it under the terms of the GNU Lesser General Public License as published by
|
|
* the Free Software Foundation, either version 3 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* This library is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU Lesser General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU Lesser General Public License
|
|
* along with this library. If not, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
/**@{*/
|
|
|
|
#include <libopencm3/cm3/assert.h>
|
|
#include <libopencm3/stm32/flash.h>
|
|
#include <libopencm3/stm32/pwr.h>
|
|
#include <libopencm3/stm32/rcc.h>
|
|
|
|
/* Set the default clock frequencies after reset. */
|
|
uint32_t rcc_ahb_frequency = 2097000;
|
|
uint32_t rcc_apb1_frequency = 2097000;
|
|
uint32_t rcc_apb2_frequency = 2097000;
|
|
|
|
void rcc_osc_on(enum rcc_osc osc)
|
|
{
|
|
switch (osc) {
|
|
case RCC_PLL:
|
|
RCC_CR |= RCC_CR_PLLON;
|
|
break;
|
|
case RCC_MSI:
|
|
RCC_CR |= RCC_CR_MSION;
|
|
break;
|
|
case RCC_HSE:
|
|
RCC_CR |= RCC_CR_HSEON;
|
|
break;
|
|
case RCC_HSI48:
|
|
RCC_CRRCR |= RCC_CRRCR_HSI48ON;
|
|
break;
|
|
case RCC_HSI16:
|
|
RCC_CR |= RCC_CR_HSI16ON;
|
|
break;
|
|
case RCC_LSE:
|
|
RCC_CSR |= RCC_CSR_LSEON;
|
|
break;
|
|
case RCC_LSI:
|
|
RCC_CSR |= RCC_CSR_LSION;
|
|
break;
|
|
}
|
|
}
|
|
|
|
void rcc_osc_off(enum rcc_osc osc)
|
|
{
|
|
switch (osc) {
|
|
case RCC_PLL:
|
|
RCC_CR &= ~RCC_CR_PLLON;
|
|
break;
|
|
case RCC_MSI:
|
|
RCC_CR &= ~RCC_CR_MSION;
|
|
break;
|
|
case RCC_HSE:
|
|
RCC_CR &= ~RCC_CR_HSEON;
|
|
break;
|
|
case RCC_HSI48:
|
|
RCC_CRRCR &= ~RCC_CRRCR_HSI48ON;
|
|
break;
|
|
case RCC_HSI16:
|
|
RCC_CR &= ~RCC_CR_HSI16ON;
|
|
break;
|
|
case RCC_LSE:
|
|
RCC_CSR &= ~RCC_CSR_LSEON;
|
|
break;
|
|
case RCC_LSI:
|
|
RCC_CSR &= ~RCC_CSR_LSION;
|
|
break;
|
|
}
|
|
}
|
|
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
/** @brief RCC Clear the Oscillator Ready Interrupt Flag
|
|
*
|
|
* Clear the interrupt flag that was set when a clock oscillator became ready
|
|
* to use.
|
|
*
|
|
* @param[in] osc Oscillator ID
|
|
*/
|
|
void rcc_osc_ready_int_clear(enum rcc_osc osc)
|
|
{
|
|
switch (osc) {
|
|
case RCC_PLL:
|
|
RCC_CICR |= RCC_CICR_PLLRDYC;
|
|
break;
|
|
case RCC_HSE:
|
|
RCC_CICR |= RCC_CICR_HSERDYC;
|
|
break;
|
|
case RCC_HSI48:
|
|
RCC_CICR |= RCC_CICR_HSI48RDYC;
|
|
break;
|
|
case RCC_HSI16:
|
|
RCC_CICR |= RCC_CICR_HSI16RDYC;
|
|
break;
|
|
case RCC_MSI:
|
|
RCC_CICR |= RCC_CICR_MSIRDYC;
|
|
break;
|
|
case RCC_LSE:
|
|
RCC_CICR |= RCC_CICR_LSERDYC;
|
|
break;
|
|
case RCC_LSI:
|
|
RCC_CICR |= RCC_CICR_LSIRDYC;
|
|
break;
|
|
}
|
|
}
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
/** @brief RCC Enable the Oscillator Ready Interrupt
|
|
*
|
|
* @param[in] osc Oscillator ID
|
|
*/
|
|
void rcc_osc_ready_int_enable(enum rcc_osc osc)
|
|
{
|
|
switch (osc) {
|
|
case RCC_PLL:
|
|
RCC_CIER |= RCC_CIER_PLLRDYIE;
|
|
break;
|
|
case RCC_HSE:
|
|
RCC_CIER |= RCC_CIER_HSERDYIE;
|
|
break;
|
|
case RCC_HSI48:
|
|
RCC_CIER |= RCC_CIER_HSI48RDYIE;
|
|
break;
|
|
case RCC_HSI16:
|
|
RCC_CIER |= RCC_CIER_HSI16RDYIE;
|
|
break;
|
|
case RCC_MSI:
|
|
RCC_CIER |= RCC_CIER_MSIRDYIE;
|
|
break;
|
|
case RCC_LSE:
|
|
RCC_CIER |= RCC_CIER_LSERDYIE;
|
|
break;
|
|
case RCC_LSI:
|
|
RCC_CIER |= RCC_CIER_LSIRDYIE;
|
|
break;
|
|
}
|
|
}
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
/** @brief RCC Disable the Oscillator Ready Interrupt
|
|
*
|
|
* @param[in] osc Oscillator ID
|
|
*/
|
|
void rcc_osc_ready_int_disable(enum rcc_osc osc)
|
|
{
|
|
switch (osc) {
|
|
case RCC_PLL:
|
|
RCC_CIER &= ~RCC_CIER_PLLRDYIE;
|
|
break;
|
|
case RCC_HSE:
|
|
RCC_CIER &= ~RCC_CIER_HSERDYIE;
|
|
break;
|
|
case RCC_HSI48:
|
|
RCC_CIER &= ~RCC_CIER_HSI48RDYIE;
|
|
break;
|
|
case RCC_HSI16:
|
|
RCC_CIER &= ~RCC_CIER_HSI16RDYIE;
|
|
break;
|
|
case RCC_MSI:
|
|
RCC_CIER &= ~RCC_CIER_MSIRDYIE;
|
|
break;
|
|
case RCC_LSE:
|
|
RCC_CIER &= ~RCC_CIER_LSERDYIE;
|
|
break;
|
|
case RCC_LSI:
|
|
RCC_CIER &= ~RCC_CIER_LSIRDYIE;
|
|
break;
|
|
}
|
|
}
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
/** @brief RCC Read the Oscillator Ready Interrupt Flag
|
|
*
|
|
* @param[in] osc Oscillator ID
|
|
* @returns int. Boolean value for flag set.
|
|
*/
|
|
int rcc_osc_ready_int_flag(enum rcc_osc osc)
|
|
{
|
|
switch (osc) {
|
|
case RCC_PLL:
|
|
return ((RCC_CIFR & RCC_CIFR_PLLRDYF) != 0);
|
|
break;
|
|
case RCC_HSE:
|
|
return ((RCC_CIFR & RCC_CIFR_HSERDYF) != 0);
|
|
break;
|
|
case RCC_HSI48:
|
|
return ((RCC_CIFR & RCC_CIFR_HSI48RDYF) != 0);
|
|
break;
|
|
case RCC_HSI16:
|
|
return ((RCC_CIFR & RCC_CIFR_HSI16RDYF) != 0);
|
|
break;
|
|
case RCC_MSI:
|
|
return ((RCC_CIFR & RCC_CIFR_MSIRDYF) != 0);
|
|
break;
|
|
case RCC_LSE:
|
|
return ((RCC_CIFR & RCC_CIFR_LSERDYF) != 0);
|
|
break;
|
|
case RCC_LSI:
|
|
return ((RCC_CIFR & RCC_CIFR_LSIRDYF) != 0);
|
|
break;
|
|
}
|
|
|
|
cm3_assert_not_reached();
|
|
}
|
|
|
|
|
|
bool rcc_is_osc_ready(enum rcc_osc osc)
|
|
{
|
|
switch (osc) {
|
|
case RCC_PLL:
|
|
return RCC_CR & RCC_CR_PLLRDY;
|
|
case RCC_HSE:
|
|
return RCC_CR & RCC_CR_HSERDY;
|
|
case RCC_HSI16:
|
|
return RCC_CR & RCC_CR_HSI16RDY;
|
|
case RCC_HSI48:
|
|
return RCC_CRRCR & RCC_CRRCR_HSI48RDY;
|
|
case RCC_MSI:
|
|
return RCC_CR & RCC_CR_MSIRDY;
|
|
case RCC_LSE:
|
|
return RCC_CSR & RCC_CSR_LSERDY;
|
|
case RCC_LSI:
|
|
return RCC_CSR & RCC_CSR_LSIRDY;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
void rcc_wait_for_osc_ready(enum rcc_osc osc)
|
|
{
|
|
while (!rcc_is_osc_ready(osc));
|
|
}
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
/** @brief RCC Set HSI48 clock source to the RC48 (CRS)
|
|
*/
|
|
void rcc_set_hsi48_source_rc48(void)
|
|
{
|
|
RCC_CCIPR |= RCC_CCIPR_HSI48SEL;
|
|
}
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
/** @brief RCC Set HSI48 clock source to the PLL
|
|
*/
|
|
void rcc_set_hsi48_source_pll(void)
|
|
{
|
|
RCC_CCIPR &= ~RCC_CCIPR_HSI48SEL;
|
|
}
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
/** @brief RCC Set the Source for the System Clock.
|
|
*
|
|
* @param[in] osc Oscillator ID. Only HSE, HSI16, MSI and PLL have effect.
|
|
*/
|
|
|
|
void rcc_set_sysclk_source(enum rcc_osc osc)
|
|
{
|
|
switch (osc) {
|
|
case RCC_PLL:
|
|
RCC_CFGR |= RCC_CFGR_SW_PLL;
|
|
break;
|
|
case RCC_HSE:
|
|
RCC_CFGR = (RCC_CFGR & ~RCC_CFGR_SW_MASK) | RCC_CFGR_SW_HSE;
|
|
break;
|
|
case RCC_HSI16:
|
|
RCC_CFGR = (RCC_CFGR & ~RCC_CFGR_SW_MASK) | RCC_CFGR_SW_HSI16;
|
|
break;
|
|
case RCC_MSI:
|
|
RCC_CFGR = (RCC_CFGR & ~RCC_CFGR_SW_MASK) | RCC_CFGR_SW_MSI;
|
|
break;
|
|
case RCC_HSI48:
|
|
case RCC_LSE:
|
|
case RCC_LSI:
|
|
break;
|
|
}
|
|
}
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
/** @brief RCC Set the PLL Multiplication Factor.
|
|
*
|
|
* @note This only has effect when the PLL is disabled.
|
|
*
|
|
* @param[in] factor PLL multiplication factor @ref rcc_cfgr_pmf
|
|
*/
|
|
|
|
void rcc_set_pll_multiplier(uint32_t factor)
|
|
{
|
|
uint32_t reg = RCC_CFGR
|
|
& ~(RCC_CFGR_PLLMUL_MASK << RCC_CFGR_PLLMUL_SHIFT);
|
|
RCC_CFGR = reg | (factor << RCC_CFGR_PLLMUL_SHIFT);
|
|
}
|
|
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
/** @brief RCC Set the PLL Division Factor.
|
|
*
|
|
* @note This only has effect when the PLL is disabled.
|
|
*
|
|
* @param[in] factor PLL multiplication factor @ref rcc_cfgr_pdf
|
|
*/
|
|
|
|
void rcc_set_pll_divider(uint32_t factor)
|
|
{
|
|
uint32_t reg = RCC_CFGR
|
|
& ~(RCC_CFGR_PLLDIV_MASK << RCC_CFGR_PLLDIV_SHIFT);
|
|
RCC_CFGR = reg | (factor << RCC_CFGR_PLLDIV_SHIFT);
|
|
}
|
|
|
|
/**
|
|
* Set the pll source.
|
|
* @param pllsrc RCC_CFGR_PLLSRC_HSI16_CLK or RCC_CFGR_PLLSRC_HSE_CLK
|
|
*/
|
|
void rcc_set_pll_source(uint32_t pllsrc)
|
|
{
|
|
uint32_t reg32;
|
|
|
|
reg32 = RCC_CFGR;
|
|
reg32 &= ~(RCC_CFGR_PLLSRC_HSE_CLK << 16);
|
|
RCC_CFGR = (reg32 | (pllsrc<<16));
|
|
}
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
/** @brief RCC Set the APB1 Prescale Factor.
|
|
*
|
|
* @note The APB1 clock frequency must not exceed 32MHz.
|
|
*
|
|
* @param[in] ppre APB prescale factor @ref rcc_cfgr_apb1pre
|
|
*/
|
|
|
|
void rcc_set_ppre1(uint32_t ppre)
|
|
{
|
|
uint32_t reg = RCC_CFGR
|
|
& ~(RCC_CFGR_PPRE1_MASK << RCC_CFGR_PPRE1_SHIFT);
|
|
RCC_CFGR = reg | (ppre << RCC_CFGR_PPRE1_SHIFT);
|
|
}
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
/** @brief RCC Set the APB2 Prescale Factor.
|
|
*
|
|
* @note The APB2 clock frequency must not exceed 32MHz.
|
|
*
|
|
* @param[in] ppre APB prescale factor @ref rcc_cfgr_apb2pre
|
|
*/
|
|
|
|
void rcc_set_ppre2(uint32_t ppre)
|
|
{
|
|
uint32_t reg = RCC_CFGR
|
|
& ~(RCC_CFGR_PPRE2_MASK << RCC_CFGR_PPRE2_SHIFT);
|
|
RCC_CFGR = reg | (ppre << RCC_CFGR_PPRE2_SHIFT);
|
|
}
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
/** @brief RCC Set the AHB Prescale Factor.
|
|
*
|
|
* @param[in] hpre Unsigned int32. AHB prescale factor @ref rcc_cfgr_ahbpre
|
|
*/
|
|
|
|
void rcc_set_hpre(uint32_t hpre)
|
|
{
|
|
uint32_t reg = RCC_CFGR & ~(RCC_CFGR_HPRE_MASK << RCC_CFGR_HPRE_SHIFT);
|
|
RCC_CFGR = reg | (hpre << RCC_CFGR_HPRE_SHIFT);
|
|
}
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
/** @brief Set the range of the MSI oscillator
|
|
*
|
|
* @param msi_range desired range @ref rcc_icscr_msirange
|
|
*/
|
|
void rcc_set_msi_range(uint32_t msi_range)
|
|
{
|
|
uint32_t reg32 = RCC_ICSCR & ~(RCC_ICSCR_MSIRANGE_MASK << RCC_ICSCR_MSIRANGE_SHIFT);
|
|
RCC_ICSCR = reg32 | (msi_range << RCC_ICSCR_MSIRANGE_SHIFT);
|
|
}
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
/** @brief Set the LPTIM1 clock source
|
|
*
|
|
* @param lptim1_sel peripheral clock source @ref rcc_ccpipr_lptim1sel
|
|
*/
|
|
void rcc_set_lptim1_sel(uint32_t lptim1_sel)
|
|
{
|
|
RCC_CCIPR &= ~(RCC_CCIPR_LPTIM1SEL_MASK << RCC_CCIPR_LPTIM1SEL_SHIFT);
|
|
RCC_CCIPR |= (lptim1_sel << RCC_CCIPR_LPTIM1SEL_SHIFT);
|
|
}
|
|
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
/** @brief Set the LPUART1 clock source
|
|
*
|
|
* @param lpuart1_sel periphral clock source @ref rcc_ccpipr_lpuart1sel
|
|
*/
|
|
void rcc_set_lpuart1_sel(uint32_t lpuart1_sel)
|
|
{
|
|
RCC_CCIPR &= ~(RCC_CCIPR_LPUART1SEL_MASK << RCC_CCIPR_LPTIM1SEL_SHIFT);
|
|
RCC_CCIPR |= (lpuart1_sel << RCC_CCIPR_LPTIM1SEL_SHIFT);
|
|
}
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
/** @brief Set the USART1 clock source
|
|
*
|
|
* @param usart1_sel periphral clock source @ref rcc_ccpipr_usart1sel
|
|
*/
|
|
void rcc_set_usart1_sel(uint32_t usart1_sel)
|
|
{
|
|
RCC_CCIPR &= ~(RCC_CCIPR_USART1SEL_MASK << RCC_CCIPR_USART1SEL_SHIFT);
|
|
RCC_CCIPR |= (usart1_sel << RCC_CCIPR_USART1SEL_SHIFT);
|
|
}
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
/** @brief Set the USART2 clock source
|
|
*
|
|
* @param usart2_sel periphral clock source @ref rcc_ccpipr_usartxsel
|
|
*/
|
|
void rcc_set_usart2_sel(uint32_t usart2_sel)
|
|
{
|
|
RCC_CCIPR &= ~(RCC_CCIPR_USART2SEL_MASK << RCC_CCIPR_USART2SEL_SHIFT);
|
|
RCC_CCIPR |= (usart2_sel << RCC_CCIPR_USART2SEL_SHIFT);
|
|
}
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
/** @brief Set the peripheral clock source
|
|
* @param periph peripheral of desire, eg XXX_BASE
|
|
* @param sel peripheral clock source
|
|
*/
|
|
void rcc_set_peripheral_clk_sel(uint32_t periph, uint32_t sel)
|
|
{
|
|
uint8_t shift;
|
|
uint32_t mask;
|
|
|
|
switch (periph) {
|
|
case LPTIM1_BASE:
|
|
shift = RCC_CCIPR_LPTIM1SEL_SHIFT;
|
|
mask = RCC_CCIPR_LPTIM1SEL_MASK;
|
|
break;
|
|
|
|
case I2C3_BASE:
|
|
shift = RCC_CCIPR_I2C3SEL_SHIFT;
|
|
mask = RCC_CCIPR_I2C3SEL_MASK;
|
|
break;
|
|
|
|
case I2C1_BASE:
|
|
shift = RCC_CCIPR_I2C1SEL_SHIFT;
|
|
mask = RCC_CCIPR_I2C1SEL_MASK;
|
|
break;
|
|
|
|
case LPUART1_BASE:
|
|
shift = RCC_CCIPR_LPUART1SEL_SHIFT;
|
|
mask = RCC_CCIPR_LPUART1SEL_MASK;
|
|
break;
|
|
|
|
case USART2_BASE:
|
|
shift = RCC_CCIPR_USART2SEL_SHIFT;
|
|
mask = RCC_CCIPR_USART2SEL_MASK;
|
|
break;
|
|
|
|
case USART1_BASE:
|
|
shift = RCC_CCIPR_USART1SEL_SHIFT;
|
|
mask = RCC_CCIPR_USART1SEL_MASK;
|
|
break;
|
|
|
|
default:
|
|
return;
|
|
}
|
|
|
|
uint32_t reg32 = RCC_CCIPR & ~(mask << shift);
|
|
RCC_CCIPR = reg32 | (sel << shift);
|
|
}
|
|
|
|
/** @brief RCC Setup PLL and use it as Sysclk source.
|
|
*
|
|
* @param[in] clock full struct with desired parameters
|
|
*
|
|
*/
|
|
void rcc_clock_setup_pll(const struct rcc_clock_scale *clock)
|
|
{
|
|
/* Turn on the appropriate source for the PLL */
|
|
if (clock->pll_source == RCC_CFGR_PLLSRC_HSE_CLK) {
|
|
rcc_osc_on(RCC_HSE);
|
|
rcc_wait_for_osc_ready(RCC_HSE);
|
|
} else {
|
|
rcc_osc_on(RCC_HSI16);
|
|
rcc_wait_for_osc_ready(RCC_HSI16);
|
|
}
|
|
|
|
rcc_set_hpre(clock->hpre);
|
|
rcc_set_ppre1(clock->ppre1);
|
|
rcc_set_ppre2(clock->ppre2);
|
|
|
|
rcc_periph_clock_enable(RCC_PWR);
|
|
pwr_set_vos_scale(clock->voltage_scale);
|
|
|
|
rcc_osc_off(RCC_PLL);
|
|
while (rcc_is_osc_ready(RCC_PLL));
|
|
|
|
flash_prefetch_enable();
|
|
flash_set_ws(clock->flash_waitstates);
|
|
|
|
/* Set up the PLL */
|
|
rcc_set_pll_multiplier(clock->pll_mul);
|
|
rcc_set_pll_divider(clock->pll_div);
|
|
rcc_set_pll_source(clock->pll_source);
|
|
|
|
rcc_osc_on(RCC_PLL);
|
|
rcc_wait_for_osc_ready(RCC_PLL);
|
|
rcc_set_sysclk_source(RCC_PLL);
|
|
|
|
/* Set the peripheral clock frequencies used. */
|
|
rcc_ahb_frequency = clock->ahb_frequency;
|
|
rcc_apb1_frequency = clock->apb1_frequency;
|
|
rcc_apb2_frequency = clock->apb2_frequency;
|
|
}
|
|
|
|
/**@}*/
|