zephyr/drivers/clock_control/stm32_ll_clock.c

341 lines
9.4 KiB
C

/*
*
* Copyright (c) 2017 Linaro Limited.
* Copyright (c) 2017 RnDity Sp. z o.o.
*
* SPDX-License-Identifier: Apache-2.0
*/
#include <soc.h>
#include <soc_registers.h>
#include <clock_control.h>
#include <misc/util.h>
#include <clock_control/stm32_clock_control.h>
#include "stm32_ll_clock.h"
/* Macros to fill up prescaler values */
#define _ahb_prescaler(v) LL_RCC_SYSCLK_DIV_ ## v
#define ahb_prescaler(v) _ahb_prescaler(v)
#define _apb1_prescaler(v) LL_RCC_APB1_DIV_ ## v
#define apb1_prescaler(v) _apb1_prescaler(v)
#ifndef CONFIG_SOC_SERIES_STM32F0X
#define _apb2_prescaler(v) LL_RCC_APB2_DIV_ ## v
#define apb2_prescaler(v) _apb2_prescaler(v)
#endif /* CONFIG_SOC_SERIES_STM32F0X */
/**
* @brief fill in AHB/APB buses configuration structure
*/
static void config_bus_clk_init(LL_UTILS_ClkInitTypeDef *clk_init)
{
clk_init->AHBCLKDivider = ahb_prescaler(
CONFIG_CLOCK_STM32_AHB_PRESCALER);
clk_init->APB1CLKDivider = apb1_prescaler(
CONFIG_CLOCK_STM32_APB1_PRESCALER);
#ifndef CONFIG_SOC_SERIES_STM32F0X
clk_init->APB2CLKDivider = apb2_prescaler(
CONFIG_CLOCK_STM32_APB2_PRESCALER);
#endif /* CONFIG_SOC_SERIES_STM32F0X */
}
static u32_t get_bus_clock(u32_t clock, u32_t prescaler)
{
return clock / prescaler;
}
static inline int stm32_clock_control_on(struct device *dev,
clock_control_subsys_t sub_system)
{
struct stm32_pclken *pclken = (struct stm32_pclken *)(sub_system);
ARG_UNUSED(dev);
switch (pclken->bus) {
case STM32_CLOCK_BUS_AHB1:
LL_AHB1_GRP1_EnableClock(pclken->enr);
break;
#if defined(CONFIG_SOC_SERIES_STM32L4X) || defined(CONFIG_SOC_SERIES_STM32F4X)
case STM32_CLOCK_BUS_AHB2:
LL_AHB2_GRP1_EnableClock(pclken->enr);
break;
#endif /* CONFIG_SOC_SERIES_STM32L4X || CONFIG_SOC_SERIES_STM32F4X */
case STM32_CLOCK_BUS_APB1:
LL_APB1_GRP1_EnableClock(pclken->enr);
break;
#if defined(CONFIG_SOC_SERIES_STM32L4X) || defined(CONFIG_SOC_SERIES_STM32F0X)
case STM32_CLOCK_BUS_APB1_2:
LL_APB1_GRP2_EnableClock(pclken->enr);
break;
#endif /* CONFIG_SOC_SERIES_STM32L4X || CONFIG_SOC_SERIES_STM32F0X */
#ifndef CONFIG_SOC_SERIES_STM32F0X
case STM32_CLOCK_BUS_APB2:
LL_APB2_GRP1_EnableClock(pclken->enr);
break;
#endif /* CONFIG_SOC_SERIES_STM32F0X */
}
return 0;
}
static inline int stm32_clock_control_off(struct device *dev,
clock_control_subsys_t sub_system)
{
struct stm32_pclken *pclken = (struct stm32_pclken *)(sub_system);
ARG_UNUSED(dev);
switch (pclken->bus) {
case STM32_CLOCK_BUS_AHB1:
LL_AHB1_GRP1_DisableClock(pclken->enr);
break;
#if defined(CONFIG_SOC_SERIES_STM32L4X) || defined(CONFIG_SOC_SERIES_STM32F4X)
case STM32_CLOCK_BUS_AHB2:
LL_AHB2_GRP1_DisableClock(pclken->enr);
break;
#endif /* CONFIG_SOC_SERIES_STM32L4X || CONFIG_SOC_SERIES_STM32F4X */
case STM32_CLOCK_BUS_APB1:
LL_APB1_GRP1_DisableClock(pclken->enr);
break;
#if defined(CONFIG_SOC_SERIES_STM32L4X) || defined(CONFIG_SOC_SERIES_STM32F0X)
case STM32_CLOCK_BUS_APB1_2:
LL_APB1_GRP2_DisableClock(pclken->enr);
break;
#endif /* CONFIG_SOC_SERIES_STM32L4X || CONFIG_SOC_SERIES_STM32F0X */
#ifndef CONFIG_SOC_SERIES_STM32F0X
case STM32_CLOCK_BUS_APB2:
LL_APB2_GRP1_DisableClock(pclken->enr);
break;
#endif /* CONFIG_SOC_SERIES_STM32F0X */
}
return 0;
}
static int stm32_clock_control_get_subsys_rate(struct device *clock,
clock_control_subsys_t sub_system,
u32_t *rate)
{
struct stm32_pclken *pclken = (struct stm32_pclken *)(sub_system);
/*
* Get AHB Clock (= SystemCoreClock = SYSCLK/prescaler)
* SystemCoreClock is preferred to CONFIG_SYS_CLOCK_HW_CYCLES_PER_SEC
* since it will be updated after clock configuration and hence
* more likely to contain actual clock speed
*/
u32_t ahb_clock = SystemCoreClock;
u32_t apb1_clock = get_bus_clock(ahb_clock,
CONFIG_CLOCK_STM32_APB1_PRESCALER);
#ifndef CONFIG_SOC_SERIES_STM32F0X
u32_t apb2_clock = get_bus_clock(ahb_clock,
CONFIG_CLOCK_STM32_APB2_PRESCALER);
#endif /* CONFIG_SOC_SERIES_STM32F0X */
ARG_UNUSED(clock);
switch (pclken->bus) {
case STM32_CLOCK_BUS_AHB1:
case STM32_CLOCK_BUS_AHB2:
*rate = ahb_clock;
break;
case STM32_CLOCK_BUS_APB1:
#if defined(CONFIG_SOC_SERIES_STM32L4X) || defined(CONFIG_SOC_SERIES_STM32F0X)
case STM32_CLOCK_BUS_APB1_2:
#endif /* CONFIG_SOC_SERIES_STM32L4X || CONFIG_SOC_SERIES_STM32F0X */
*rate = apb1_clock;
break;
#ifndef CONFIG_SOC_SERIES_STM32F0X
case STM32_CLOCK_BUS_APB2:
*rate = apb2_clock;
break;
#endif /* CONFIG_SOC_SERIES_STM32F0X */
}
return 0;
}
static struct clock_control_driver_api stm32_clock_control_api = {
.on = stm32_clock_control_on,
.off = stm32_clock_control_off,
.get_rate = stm32_clock_control_get_subsys_rate,
};
/*
* Unconditionally switch the system clock source to HSI.
*/
__unused
static void stm32_clock_switch_to_hsi(u32_t ahb_prescaler)
{
/* Enable HSI if not enabled */
if (LL_RCC_HSI_IsReady() != 1) {
/* Enable HSI */
LL_RCC_HSI_Enable();
while (LL_RCC_HSI_IsReady() != 1) {
/* Wait for HSI ready */
}
}
/* Set HSI as SYSCLCK source */
LL_RCC_SetSysClkSource(LL_RCC_SYS_CLKSOURCE_HSI);
LL_RCC_SetAHBPrescaler(ahb_prescaler);
while (LL_RCC_GetSysClkSource() != LL_RCC_SYS_CLKSOURCE_STATUS_HSI) {
}
}
static int stm32_clock_control_init(struct device *dev)
{
LL_UTILS_ClkInitTypeDef s_ClkInitStruct;
ARG_UNUSED(dev);
/* configure clock for AHB/APB buses */
config_bus_clk_init((LL_UTILS_ClkInitTypeDef *)&s_ClkInitStruct);
/* Some clocks would be activated by default */
config_enable_default_clocks();
#ifdef CONFIG_CLOCK_STM32_SYSCLK_SRC_PLL
LL_UTILS_PLLInitTypeDef s_PLLInitStruct;
/* configure PLL input settings */
config_pll_init(&s_PLLInitStruct);
/*
* Switch to HSI and disable the PLL before configuration.
* (Switching to HSI makes sure we have a SYSCLK source in
* case we're currently running from the PLL we're about to
* turn off and reconfigure.)
*
* Don't use s_ClkInitStruct.AHBCLKDivider as the AHB
* prescaler here. In this configuration, that's the value to
* use when the SYSCLK source is the PLL, not HSI.
*/
stm32_clock_switch_to_hsi(LL_RCC_SYSCLK_DIV_1);
LL_RCC_PLL_Disable();
#ifdef CONFIG_CLOCK_STM32_PLL_Q_DIVISOR
MODIFY_REG(RCC->PLLCFGR, RCC_PLLCFGR_PLLQ,
CONFIG_CLOCK_STM32_PLL_Q_DIVISOR
<< POSITION_VAL(RCC_PLLCFGR_PLLQ));
#endif /* CONFIG_CLOCK_STM32_PLL_Q_DIVISOR */
#ifdef CONFIG_CLOCK_STM32_PLL_SRC_MSI
/* Switch to PLL with MSI as clock source */
LL_PLL_ConfigSystemClock_MSI(&s_PLLInitStruct, &s_ClkInitStruct);
/* Disable other clocks */
LL_RCC_HSI_Disable();
LL_RCC_HSE_Disable();
#elif CONFIG_CLOCK_STM32_PLL_SRC_HSI
/* Switch to PLL with HSI as clock source */
LL_PLL_ConfigSystemClock_HSI(&s_PLLInitStruct, &s_ClkInitStruct);
/* Disable other clocks */
LL_RCC_HSE_Disable();
LL_RCC_MSI_Disable();
#elif CONFIG_CLOCK_STM32_PLL_SRC_HSE
int hse_bypass = LL_UTILS_HSEBYPASS_OFF;
#ifdef CONFIG_CLOCK_STM32_HSE_BYPASS
hse_bypass = LL_UTILS_HSEBYPASS_ON;
#endif /* CONFIG_CLOCK_STM32_HSE_BYPASS */
/* Switch to PLL with HSE as clock source */
LL_PLL_ConfigSystemClock_HSE(CONFIG_CLOCK_STM32_HSE_CLOCK, hse_bypass,
&s_PLLInitStruct,
&s_ClkInitStruct);
/* Disable other clocks */
LL_RCC_HSI_Disable();
LL_RCC_MSI_Disable();
#endif /* CONFIG_CLOCK_STM32_PLL_SRC_... */
#elif CONFIG_CLOCK_STM32_SYSCLK_SRC_HSE
/* Enable HSE if not enabled */
if (LL_RCC_HSE_IsReady() != 1) {
/* Check if need to enable HSE bypass feature or not */
#ifdef CONFIG_CLOCK_STM32_HSE_BYPASS
LL_RCC_HSE_EnableBypass();
#else
LL_RCC_HSE_DisableBypass();
#endif /* CONFIG_CLOCK_STM32_HSE_BYPASS */
/* Enable HSE */
LL_RCC_HSE_Enable();
while (LL_RCC_HSE_IsReady() != 1) {
/* Wait for HSE ready */
}
}
/* Set HSE as SYSCLCK source */
LL_RCC_SetSysClkSource(LL_RCC_SYS_CLKSOURCE_HSE);
LL_RCC_SetAHBPrescaler(s_ClkInitStruct.AHBCLKDivider);
while (LL_RCC_GetSysClkSource() != LL_RCC_SYS_CLKSOURCE_STATUS_HSE) {
}
/* Update SystemCoreClock variable */
LL_SetSystemCoreClock(__LL_RCC_CALC_HCLK_FREQ(
CONFIG_CLOCK_STM32_HSE_CLOCK,
s_ClkInitStruct.AHBCLKDivider));
/* Set APB1 & APB2 prescaler*/
LL_RCC_SetAPB1Prescaler(s_ClkInitStruct.APB1CLKDivider);
#ifndef CONFIG_SOC_SERIES_STM32F0X
LL_RCC_SetAPB2Prescaler(s_ClkInitStruct.APB2CLKDivider);
#endif /* CONFIG_SOC_SERIES_STM32F0X */
/* Set flash latency */
/* HSI used as SYSCLK, set latency to 0 */
LL_FLASH_SetLatency(LL_FLASH_LATENCY_0);
/* Disable other clocks */
LL_RCC_HSI_Disable();
LL_RCC_MSI_Disable();
LL_RCC_PLL_Disable();
#elif CONFIG_CLOCK_STM32_SYSCLK_SRC_HSI
stm32_clock_switch_to_hsi(s_ClkInitStruct.AHBCLKDivider);
/* Update SystemCoreClock variable */
LL_SetSystemCoreClock(__LL_RCC_CALC_HCLK_FREQ(HSI_VALUE,
s_ClkInitStruct.AHBCLKDivider));
/* Set APB1 & APB2 prescaler*/
LL_RCC_SetAPB1Prescaler(s_ClkInitStruct.APB1CLKDivider);
#ifndef CONFIG_SOC_SERIES_STM32F0X
LL_RCC_SetAPB2Prescaler(s_ClkInitStruct.APB2CLKDivider);
#endif /* CONFIG_SOC_SERIES_STM32F0X */
/* Set flash latency */
/* HSI used as SYSCLK, set latency to 0 */
LL_FLASH_SetLatency(LL_FLASH_LATENCY_0);
/* Disable other clocks */
LL_RCC_HSE_Disable();
LL_RCC_MSI_Disable();
LL_RCC_PLL_Disable();
#endif /* CONFIG_CLOCK_STM32_SYSCLK_SRC_... */
return 0;
}
/**
* @brief RCC device, note that priority is intentionally set to 1 so
* that the device init runs just after SOC init
*/
DEVICE_AND_API_INIT(rcc_stm32, STM32_CLOCK_CONTROL_NAME,
&stm32_clock_control_init,
NULL, NULL,
PRE_KERNEL_1,
CONFIG_CLOCK_CONTROL_STM32_DEVICE_INIT_PRIORITY,
&stm32_clock_control_api);