Added support for USARTs and clock setup

Tested:
- USART2 Rx/Tx with:
    - In 8N1 115200
    - With sysclk set as HSI and default setup
    - With all clk input types for USART2
This commit is contained in:
Mateusz Myalski
2024-10-11 11:51:07 +02:00
committed by Piotr Esden-Tempski
parent f1df03ce9e
commit e6632cda77
6 changed files with 797 additions and 7 deletions

View File

@@ -270,7 +270,7 @@ specific memorymap.h header before including this header file.*/
BEGIN_DECLS BEGIN_DECLS
/* /*
* Note: The F2 and F4 series have a completely new GPIO peripheral with * Note: The F2, U5 and F4 series have a completely new GPIO peripheral with
* different configuration options. Here we implement a different API partly to * different configuration options. Here we implement a different API partly to
* more closely match the peripheral capabilities and also to deliberately * more closely match the peripheral capabilities and also to deliberately
* break compatibility with old F1 code so there is no confusion with similar * break compatibility with old F1 code so there is no confusion with similar

View File

@@ -43,6 +43,18 @@
/* Module definitions */ /* Module definitions */
/*****************************************************************************/ /*****************************************************************************/
struct rcc_clock_scale {
uint8_t hpre; /* AHB prescaler */
uint8_t ppre1; /* APB1 low-speed prescaler */
uint8_t ppre2; /* APB2 high-speed prescaler */
uint32_t ahb_frequency; /* AHB clock frequency */
uint32_t apb1_frequency; /* APB1 clock frequency */
uint32_t apb2_frequency; /* APB2 clock frequency */
// enum pwr_vos_scale vos_scale; /* Dynamic voltage scale */ TODO
};
extern const struct rcc_clock_scale rcc_hsi16mhz_configs;
/*****************************************************************************/ /*****************************************************************************/
/* Register definitions */ /* Register definitions */
/*****************************************************************************/ /*****************************************************************************/
@@ -51,46 +63,165 @@
#define RCC_CFGR MMIO32(RCC_BASE + 0x1c) #define RCC_CFGR MMIO32(RCC_BASE + 0x1c)
#define RCC_CFGR2 MMIO32(RCC_BASE + 0x20) #define RCC_CFGR2 MMIO32(RCC_BASE + 0x20)
#define RCC_CFGR3 MMIO32(RCC_BASE + 0x24) #define RCC_CFGR3 MMIO32(RCC_BASE + 0x24)
#define RCC_CCIPR1 MMIO32(RCC_BASE + 0xE0)
#define RCC_CCIPR2 MMIO32(RCC_BASE + 0xE4)
#define RCC_CFGR_SWS_SHIFT 2
#define RCC_CFGR_SWS_MASK 0x3
#define RCC_CFGR_SWS (0x3 << RCC_CFGR_SWS_SHIFT)
#define RCC_CFGR_SWS_MSIS 0x0
#define RCC_CFGR_SWS_HSI16 0x1
#define RCC_CFGR_SWS_HE 0x2
#define RCC_CFGR_SWS_PLL 0x3
#define RCC_CFGR_SW_SYSCLKSEL_SHIFT 0
#define RCC_CFGR_SW_SYSCLKSEL_MASK 0x3
#define RCC_CFGR_SW_SYSCLKSEL_MSIS 0x0
#define RCC_CFGR_SW_SYSCLKSEL_HSI16 0x1
#define RCC_CFGR_SW_SYSCLKSEL_HSE 0x2
#define RCC_CFGR_SW_SYSCLKSEL_PLL 0x3
/*****************************************************************************/ /*****************************************************************************/
/* Register values */ /* Register values */
/*****************************************************************************/ /*****************************************************************************/
/* --- RCC_CR values ------------------------------------------------------- */ /* --- RCC_CR values ------------------------------------------------------- */
#define RCC_CR_HSEBYP (1 << 18) #define RCC_CR_PLL3RDY (1 << 29)
#define RCC_CR_PLL3ON (1 << 28)
#define RCC_CR_PLL2RDY (1 << 27)
#define RCC_CR_PLL2ON (1 << 26)
#define RCC_CR_PLL1RDY (1 << 25)
#define RCC_CR_PLL1ON (1 << 24)
#define RCC_CR_HSEEXT (1 << 20)
#define RCC_CR_CSSON (1 << 19)
#define RCC_CR_HSEBYP (1 << 18)
#define RCC_CR_HSERDY (1 << 17)
#define RCC_CR_HSEON (1 << 16)
#define RCC_CR_SHSIRDY (1 << 15)
#define RCC_CR_SHSION (1 << 14)
#define RCC_CR_HSI48RDY (1 << 13)
#define RCC_CR_HSI48ON (1 << 12)
#define RCC_CR_HSIRDY (1 << 10)
#define RCC_CR_HSIKERON (1 << 9)
#define RCC_CR_HSION (1 << 8)
#define RCC_CR_MSIPLFAST (1 << 7)
#define RCC_CR_MSIKRDY (1 << 5)
#define RCC_CR_MSIKON (1 << 4)
#define RCC_CR_MSIPLLEN (1 << 3)
#define RCC_CR_MSISRDY (1 << 2)
#define RCC_CR_MSIKERON (1 << 1)
#define RCC_CR_MSISON (1 << 0)
/* --- RCC_CFGR values ----------------------------------------------------- */ /* --- RCC_CFGR values ----------------------------------------------------- */
#define RCC_CFGR_MCO_SHIFT 24 #define RCC_CFGR_MCO_SHIFT 24
#define RCC_CFGR_MCO_MASK 0xf #define RCC_CFGR_MCO_MASK 0xf
#define RCC_CFGR_HPRE_SHIFT 0
#define RCC_CFGR_HPRE (0xf << RCC_CFGR_HPRE_SHIFT)
#define RCC_CFGR_HPRE_MASK 0xf
/** @defgroup rcc_cfgr_ahbpre RCC_CFGR AHB prescale factors
@{*/
#define RCC_CFGR_HPRE_NODIV 0x0
#define RCC_CFGR_HPRE_DIV2 0x8
#define RCC_CFGR_HPRE_DIV4 0x9
#define RCC_CFGR_HPRE_DIV8 0xA
#define RCC_CFGR_HPRE_DIV16 0xB
#define RCC_CFGR_HPRE_DIV64 0xC
#define RCC_CFGR_HPRE_DIV128 0xD
#define RCC_CFGR_HPRE_DIV256 0xE
#define RCC_CFGR_HPRE_DIV512 0xF
/**@}*/
#define RCC_CFGR_PPRE1_SHIFT 4
#define RCC_CFGR_PPRE1 (0x7 << RCC_CFGR_PPRE1_SHIFT)
#define RCC_CFGR_PPRE1_MASK 0x7
#define RCC_CFGR_PPRE2_SHIFT 8
#define RCC_CFGR_PPRE2 (0x7 << RCC_CFGR_PPRE2_SHIFT)
#define RCC_CFGR_PPRE2_MASK 0x7
/** @defgroup rcc_cfgr_apbxpre RCC_CFGR APBx prescale factors
* These can be used for both APB1 and APB2 prescaling
* @{
*/
#define RCC_CFGR_PPRE_NODIV 0x0
#define RCC_CFGR_PPRE_DIV2 0x4
#define RCC_CFGR_PPRE_DIV4 0x5
#define RCC_CFGR_PPRE_DIV8 0x6
#define RCC_CFGR_PPRE_DIV16 0x7
/**@}*/
/* --- RCC_BDCR values ----------------------------------------------------- */ /* --- RCC_BDCR values ----------------------------------------------------- */
#define RCC_BDCR MMIO32(RCC_BASE + 0xF0) #define RCC_BDCR MMIO32(RCC_BASE + 0xF0)
#define RCC_BDCR_LSEBYP (1 << 2) #define RCC_BDCR_LSEBYP (1 << 2)
/* --- RCC_CCIPR1 values ---------------------------------------------------- */
#define RCC_CCIPR_USARTxSEL_MASK 0x3
#define RCC_CCIPR1_USART5SEL_SHIFT 8
#define RCC_CCIPR1_USART4SEL_SHIFT 6
#define RCC_CCIPR1_USART3SEL_SHIFT 4
#define RCC_CCIPR1_USART2SEL_SHIFT 2
#define RCC_CCIPR1_USART1SEL_SHIFT 0
#define RCC_CCIPR_USARTxSEL_PCLKx 0x0
#define RCC_CCIPR_USARTxSEL_SYSCLK 0x1
#define RCC_CCIPR_USARTxSEL_HSI16 0x2
#define RCC_CCIPR_USARTxSEL_LSE 0x3
/* --- RCC_CCIPR2 values ---------------------------------------------------- */
#define RCC_CCIPR2_USART6SEL_SHIFT 16
/*****************************************************************************/ /*****************************************************************************/
/* API definitions */ /* API definitions */
/*****************************************************************************/ /*****************************************************************************/
/* --- Variable definitions ------------------------------------------------ */
extern uint32_t rcc_ahb_frequency;
extern uint32_t rcc_apb1_frequency;
extern uint32_t rcc_apb2_frequency;
enum rcc_osc { enum rcc_osc {
RCC_PLL, RCC_PLL3,
RCC_PLL2,
RCC_PLL1,
RCC_SHSI,
RCC_HSE, RCC_HSE,
RCC_HSI, RCC_HSI,
RCC_HSI16, RCC_HSI16,
RCC_MSIS, RCC_MSIS,
RCC_MSIK, RCC_MSI,
RCC_LSI, RCC_LSI,
RCC_LSE, RCC_LSE,
RCC_HSI48, RCC_HSI48,
RCC_SHSI,
}; };
#define _REG_BIT(base, bit) (((base) << 5) + (bit)) #define _REG_BIT(base, bit) (((base) << 5) + (bit))
enum rcc_periph_rst { enum rcc_periph_rst {
/* AHB1 peripherals */
RST_GPDMA = _REG_BIT(0x60, 0),
RST_CORDIC = _REG_BIT(0x60, 1),
RST_FMAC = _REG_BIT(0x60, 2),
RST_MDF1 = _REG_BIT(0x60, 3),
RST_CRC = _REG_BIT(0x60, 12),
RST_JPEG = _REG_BIT(0x60, 15),
RST_TSCRS = _REG_BIT(0x60, 16),
RST_RAMCFG = _REG_BIT(0x60, 17),
RST_DMA2D = _REG_BIT(0x60, 18),
RST_GFXMMU = _REG_BIT(0x60, 19),
RST_GPU2D = _REG_BIT(0x60, 20),
/* AHB2 peripherals */ /* AHB2 peripherals */
RST_GPIOA = _REG_BIT(0x64, 0), RST_GPIOA = _REG_BIT(0x64, 0),
RST_GPIOB = _REG_BIT(0x64, 1), RST_GPIOB = _REG_BIT(0x64, 1),
@@ -100,10 +231,105 @@ enum rcc_periph_rst {
RST_GPIOF = _REG_BIT(0x64, 5), RST_GPIOF = _REG_BIT(0x64, 5),
RST_GPIOG = _REG_BIT(0x64, 6), RST_GPIOG = _REG_BIT(0x64, 6),
RST_GPIOH = _REG_BIT(0x64, 7), RST_GPIOH = _REG_BIT(0x64, 7),
RST_GPIOI = _REG_BIT(0x64, 8),
RST_GPIOJ = _REG_BIT(0x64, 9),
RST_ADC12 = _REG_BIT(0x64, 10),
RST_DCMI = _REG_BIT(0x64, 12),
RST_OTG = _REG_BIT(0x64, 14),
RST_AES = _REG_BIT(0x64, 16),
RST_HASH = _REG_BIT(0x64, 17),
RST_RNG = _REG_BIT(0x64, 18),
RST_PKA = _REG_BIT(0x64, 19),
RST_SAES = _REG_BIT(0x64, 20),
RST_OTFDEC1 = _REG_BIT(0x64, 23),
RST_OTFDEC2 = _REG_BIT(0x64, 24),
RST_SDMMC1 = _REG_BIT(0x64, 27),
RST_SDMMC2 = _REG_BIT(0x64, 28),
RST_FSMC = _REG_BIT(0x68, 0),
RST_OCTOSPI1 = _REG_BIT(0x68, 4),
RST_OCTOSPI2 = _REG_BIT(0x68, 8),
RST_HSPI1 = _REG_BIT(0x68, 12),
/* AHB3 peripherals */
RST_LPGIO1 = _REG_BIT(0x6C, 0),
RST_ADC4 = _REG_BIT(0x6C, 5),
RST_LPDMA1 = _REG_BIT(0x6C, 9),
RST_ADF1 = _REG_BIT(0x6C, 10),
/* APB1 peripherals */
RST_TIM2 = _REG_BIT(0x74, 0),
RST_TIM3 = _REG_BIT(0x74, 1),
RST_TIM4 = _REG_BIT(0x74, 2),
RST_TIM5 = _REG_BIT(0x74, 3),
RST_TIM6 = _REG_BIT(0x74, 4),
RST_TIM7 = _REG_BIT(0x74, 5),
RST_SPI2 = _REG_BIT(0x74, 14),
RST_USART2 = _REG_BIT(0x74, 17),
RST_USART3 = _REG_BIT(0x74, 18),
RST_USART4 = _REG_BIT(0x74, 19),
RST_USART5 = _REG_BIT(0x74, 20),
RST_I2C1 = _REG_BIT(0x74, 21),
RST_I2C2 = _REG_BIT(0x74, 22),
RST_CRS = _REG_BIT(0x74, 24),
RST_USART6 = _REG_BIT(0x74, 25),
RST_I2C4 = _REG_BIT(0x78, 1),
RST_LPTIM2 = _REG_BIT(0x78, 5),
RST_I2C5 = _REG_BIT(0x78, 6),
RST_I2C6 = _REG_BIT(0x78, 7),
RST_FDCAN1 = _REG_BIT(0x78, 9),
RST_UCPD1 = _REG_BIT(0x78, 23),
/* APB2 peripherals*/
RST_TIM1 = _REG_BIT(0x7C, 11),
RST_SPI1 = _REG_BIT(0x7C, 12),
RST_TIM8 = _REG_BIT(0x7C, 13),
RST_USART1 = _REG_BIT(0x7C, 14),
RST_TIM15 = _REG_BIT(0x7C, 16),
RST_TIM16 = _REG_BIT(0x7C, 17),
RST_TIM17 = _REG_BIT(0x7C, 18),
RST_SAI1 = _REG_BIT(0x7C, 21),
RST_SAI2 = _REG_BIT(0x7C, 22),
RST_USB = _REG_BIT(0x7C, 24),
RST_GFXTIM = _REG_BIT(0x7C, 25),
RST_LTDCR = _REG_BIT(0x7C, 26),
RST_DSI = _REG_BIT(0x7C, 27),
/* APB3 peripherals */
RST_SYSCFG = _REG_BIT(0x80, 1),
RST_SPI3 = _REG_BIT(0x80, 5),
RST_LPUART1 = _REG_BIT(0x80, 6),
RST_I2C3 = _REG_BIT(0x80, 7),
RST_LPTIM1 = _REG_BIT(0x80, 11),
RST_LPTIM3 = _REG_BIT(0x80, 12),
RST_LPTIM4 = _REG_BIT(0x80, 13),
RST_OPAMP = _REG_BIT(0x80, 14),
RST_COMP = _REG_BIT(0x80, 15),
RST_VREF = _REG_BIT(0x80, 20),
}; };
enum rcc_periph_clken { enum rcc_periph_clken {
/* AHB1 peripherals */
RCC_GPDMA = _REG_BIT(0x88, 0),
RCC_CORDIC = _REG_BIT(0x88, 1),
RCC_FMAC = _REG_BIT(0x88, 2),
RCC_MDF1 = _REG_BIT(0x88, 3),
RCC_FLASH = _REG_BIT(0x88, 8),
RCC_CRCS = _REG_BIT(0x88, 12),
RCC_JPEG = _REG_BIT(0x88, 15),
RCC_TSCR = _REG_BIT(0x88, 16),
RCC_RAMCFG = _REG_BIT(0x88, 17),
RCC_DMA2D = _REG_BIT(0x88, 18),
RCC_GFXMMU = _REG_BIT(0x88, 19),
RCC_GPU2D = _REG_BIT(0x88, 20),
RCC_DCACHE2 = _REG_BIT(0x88, 21),
RCC_GTZC1 = _REG_BIT(0x88, 24),
RCC_BKPSRAM = _REG_BIT(0x88, 28),
RCC_DCACHE1 = _REG_BIT(0x88, 30),
RCC_SRAM1 = _REG_BIT(0x88, 31),
/* AHB2 peripherals */ /* AHB2 peripherals */
RCC_GPIOA = _REG_BIT(0x8C, 0), RCC_GPIOA = _REG_BIT(0x8C, 0),
RCC_GPIOB = _REG_BIT(0x8C, 1), RCC_GPIOB = _REG_BIT(0x8C, 1),
@@ -113,6 +339,59 @@ enum rcc_periph_clken {
RCC_GPIOF = _REG_BIT(0x8C, 5), RCC_GPIOF = _REG_BIT(0x8C, 5),
RCC_GPIOG = _REG_BIT(0x8C, 6), RCC_GPIOG = _REG_BIT(0x8C, 6),
RCC_GPIOH = _REG_BIT(0x8C, 7), RCC_GPIOH = _REG_BIT(0x8C, 7),
RCC_GPIOI = _REG_BIT(0x8C, 8),
RCC_GPIOJ = _REG_BIT(0x8C, 9),
/* APB1 peripherals */
RCC_TIM2 = _REG_BIT(0x9C, 0),
RCC_TIM3 = _REG_BIT(0x9C, 1),
RCC_TIM4 = _REG_BIT(0x9C, 2),
RCC_TIM5 = _REG_BIT(0x9C, 3),
RCC_TIM6 = _REG_BIT(0x9C, 4),
RCC_TIM7 = _REG_BIT(0x9C, 5),
RCC_WWDG = _REG_BIT(0x9C, 11),
RCC_SPI2 = _REG_BIT(0x9C, 14),
RCC_USART2 = _REG_BIT(0x9C, 17),
RCC_USART3 = _REG_BIT(0x9C, 18),
RCC_USART4 = _REG_BIT(0x9C, 19),
RCC_USART5 = _REG_BIT(0x9C, 20),
RCC_I2C1 = _REG_BIT(0x9C, 21),
RCC_I2C2 = _REG_BIT(0x9C, 22),
RCC_CRS = _REG_BIT(0x9C, 24),
RCC_USART6 = _REG_BIT(0x9C, 25),
RCC_I2C4 = _REG_BIT(0x9C, 1),
RCC_LPTIM2 = _REG_BIT(0x9C, 5),
RCC_I2C5 = _REG_BIT(0x9C, 6),
RCC_I2C6 = _REG_BIT(0x9C, 7),
RCC_FDCAN1 = _REG_BIT(0x9C, 9),
RCC_UCPD1 = _REG_BIT(0x9C, 23),
/* APB2 peripherals */
RCC_TIM1 = _REG_BIT(0xA4, 11),
RCC_SPI1 = _REG_BIT(0xA4, 12),
RCC_TIM8 = _REG_BIT(0xA4, 13),
RCC_USART1 = _REG_BIT(0xA4, 14),
RCC_TIM15 = _REG_BIT(0xA4, 16),
RCC_TIM16 = _REG_BIT(0xA4, 17),
RCC_TIM17 = _REG_BIT(0xA4, 18),
RCC_SAI1 = _REG_BIT(0xA4, 21),
RCC_SAI2 = _REG_BIT(0xA4, 22),
RCC_USB = _REG_BIT(0xA4, 24),
RCC_GFXTIM = _REG_BIT(0xA4, 25),
RCC_LTDCR = _REG_BIT(0xA4, 26),
RCC_DSI = _REG_BIT(0xA4, 27),
/* APB3 peripherals */
RCC_SYSCFG = _REG_BIT(0xA8, 1),
RCC_SPI3 = _REG_BIT(0xA8, 5),
RCC_LPUART1 = _REG_BIT(0xA8, 6),
RCC_I2C3 = _REG_BIT(0xA8, 7),
RCC_LPTIM1 = _REG_BIT(0xA8, 11),
RCC_LPTIM3 = _REG_BIT(0xA8, 12),
RCC_LPTIM4 = _REG_BIT(0xA8, 13),
RCC_OPAMP = _REG_BIT(0xA8, 14),
RCC_COMP = _REG_BIT(0xA8, 15),
RCC_VREF = _REG_BIT(0xA8, 20),
}; };
#undef _REG_BIT #undef _REG_BIT
@@ -123,7 +402,18 @@ enum rcc_periph_clken {
#include <libopencm3/stm32/common/rcc_common_all.h> #include <libopencm3/stm32/common/rcc_common_all.h>
BEGIN_DECLS BEGIN_DECLS
uint32_t rcc_get_usart_clk_freq(uint32_t usart);
void rcc_osc_on(enum rcc_osc osc);
void rcc_osc_off(enum rcc_osc osc);
void rcc_css_enable(void);
void rcc_css_disable(void);
void rcc_set_sysclk_source(enum rcc_osc clk);
uint32_t rcc_system_clock_source(void);
void rcc_set_peripheral_clk_sel(uint32_t periph, uint32_t sel);
void rcc_clock_setup_hsi(const struct rcc_clock_scale *clock);
void rcc_set_ppre2(uint32_t ppre1);
void rcc_set_ppre1(uint32_t ppre1);
void rcc_set_hpre(uint32_t hpre);
END_DECLS END_DECLS
/**@}*/ /**@}*/

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@@ -0,0 +1,70 @@
/** @defgroup usart_defines USART Defines
*
* @brief <b>Defined Constants and Types for the STM32U5xxx USART</b>
*
* @ingroup STM32U5xxx_defines
*
* @version 1.0.0
*
* @date 8 October 2024
*
* LGPL License Terms @ref lgpl_license
*/
/*
* This file is part of the libopencm3 project.
*
* 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/>.
*/
#ifndef LIBOPENCM3_USART_H
#define LIBOPENCM3_USART_H
#include <libopencm3/stm32/common/usart_common_all.h>
#include <libopencm3/stm32/common/usart_common_v2.h>
/**@{*/
/*****************************************************************************/
/* Module definitions */
/*****************************************************************************/
/** @defgroup usart_reg_base USART register base addresses
* Holds all the U(S)ART peripherals supported.
* @{
*/
#define USART1 USART1_BASE
#define USART2 USART2_BASE
#define USART3 USART3_BASE
#define USART4 USART4_BASE
#define USART5 USART5_BASE
#define USART6 USART6_BASE
/**@}*/
/*****************************************************************************/
/* Register values */
/*****************************************************************************/
/*****************************************************************************/
/* API Functions */
/*****************************************************************************/
BEGIN_DECLS
END_DECLS
/**@}*/
#endif

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@@ -38,6 +38,8 @@
# include <libopencm3/stm32/l1/usart.h> # include <libopencm3/stm32/l1/usart.h>
#elif defined(STM32L4) #elif defined(STM32L4)
# include <libopencm3/stm32/l4/usart.h> # include <libopencm3/stm32/l4/usart.h>
#elif defined(STM32U5)
# include <libopencm3/stm32/u5/usart.h>
#elif defined(STM32G0) #elif defined(STM32G0)
# include <libopencm3/stm32/g0/usart.h> # include <libopencm3/stm32/g0/usart.h>
#elif defined(STM32G4) #elif defined(STM32G4)

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@@ -35,8 +35,9 @@ TGT_CFLAGS += $(STANDARD_FLAGS)
ARFLAGS = rcs ARFLAGS = rcs
OBJS += usart_common_all.o usart_common_v2.o
OBJS += gpio_common_all.o gpio_common_f0234.o OBJS += gpio_common_all.o gpio_common_f0234.o
OBJS += rcc_common_all.o OBJS += rcc.o rcc_common_all.o
VPATH += ../:../../cm3:../common VPATH += ../:../../cm3:../common

427
lib/stm32/u5/rcc.c Normal file
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@@ -0,0 +1,427 @@
/** @defgroup rcc_file RCC peripheral API
*
* @ingroup peripheral_apis
*
* @brief <b>libopencm3 STM32U5xx Reset and Clock Control</b>
*
* @version 1.0.0
*
* @date 09 Oct 2024
*
* This library supports the Reset and Clock Control System in the STM32U5xx
* series of ARM Cortex Microcontrollers by ST Microelectronics.
*
* LGPL License Terms @ref lgpl_license
*/
/*
* This file is part of the libopencm3 project.
*
* Copyright (C) 2009 Federico Ruiz-Ugalde <memeruiz at gmail dot com>
* Copyright (C) 2009 Uwe Hermann <uwe@hermann-uwe.de>
* Copyright (C) 2010 Thomas Otto <tommi@viadmin.org>
*
* 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/rcc.h>
/* Set the default clock frequencies */
#define RCC_DEFAULT_MSIS_FREQUENCY 4000000U
#define RCC_DEFAULT_HSI48_FREQUENCY 48000000U
#define RCC_DEFAULT_SHSI_FREQUENCY 48000000U
#define RCC_DEFAULT_HSI16_FREQUENCY 16000000U
#define RCC_DEFAULT_LSI_FREQUENCY 32000U
#define RCC_DEFAULT_LSE_FREQUENCY 32768U
uint32_t rcc_ahb_frequency = RCC_DEFAULT_MSIS_FREQUENCY;
uint32_t rcc_apb1_frequency = RCC_DEFAULT_MSIS_FREQUENCY;
uint32_t rcc_apb2_frequency = RCC_DEFAULT_MSIS_FREQUENCY;
const struct rcc_clock_scale rcc_hsi16mhz_configs = {
.hpre = RCC_CFGR_HPRE_NODIV,
.ppre1 = RCC_CFGR_PPRE_NODIV,
.ppre2 = RCC_CFGR_PPRE_NODIV,
.ahb_frequency = RCC_DEFAULT_HSI16_FREQUENCY,
.apb1_frequency = RCC_DEFAULT_HSI16_FREQUENCY,
.apb2_frequency = RCC_DEFAULT_HSI16_FREQUENCY,
};
void rcc_set_ppre2(uint32_t ppre2)
{
uint32_t reg32;
reg32 = RCC_CFGR;
reg32 &= ~RCC_CFGR_PPRE2;
RCC_CFGR = (reg32 | (ppre2 << RCC_CFGR_PPRE2_SHIFT));
}
void rcc_set_ppre1(uint32_t ppre1)
{
uint32_t reg32;
reg32 = RCC_CFGR;
reg32 &= ~RCC_CFGR_PPRE1;
RCC_CFGR = (reg32 | (ppre1 << RCC_CFGR_PPRE1_SHIFT));
}
void rcc_set_hpre(uint32_t hpre)
{
uint32_t reg32;
reg32 = RCC_CFGR;
reg32 &= ~RCC_CFGR_HPRE;
RCC_CFGR = (reg32 | (hpre << RCC_CFGR_HPRE_SHIFT));
}
/**
* Switch sysclock to HSI with the given parameters.
* This should be usable from any point in time, but only if you have used
* library functions to manage clocks. It relies on the global
* @ref rcc_ahb_frequency to ensure that it reliably scales voltage up or down
* as appropriate.
* @param clock full struct with desired parameters
*/
void rcc_clock_setup_hsi(const struct rcc_clock_scale *clock)
{
/* Enable internal high-speed oscillator. */
rcc_osc_on(RCC_HSI);
/* Don't try and go to fast for a voltage range! */
if (clock->ahb_frequency > rcc_ahb_frequency) {
/* Going up, power up first */
// pwr_set_vos_scale(clock->voltage_scale); TODO
rcc_set_hpre(clock->hpre);
rcc_set_ppre1(clock->ppre1);
rcc_set_ppre2(clock->ppre2);
} else {
/* going down, slow down before cutting power */
rcc_set_hpre(clock->hpre);
rcc_set_ppre1(clock->ppre1);
rcc_set_ppre2(clock->ppre2);
// pwr_set_vos_scale(clock->voltage_scale); TODO
}
rcc_wait_for_osc_ready(RCC_HSI);
rcc_set_sysclk_source(RCC_HSI16);
/* Set the peripheral clock frequencies used. */
rcc_ahb_frequency = clock->ahb_frequency;
rcc_apb1_frequency = clock->apb1_frequency;
rcc_apb2_frequency = clock->apb2_frequency;
}
/*---------------------------------------------------------------------------*/
/** @brief RCC Get the System Clock Source.
* @returns Unsigned int32. System clock source:
* @li 00 indicates MSIS
* @li 01 indicates HSI16
* @li 02 indicates HSE
* @li 03 indicates PLL
*/
uint32_t rcc_system_clock_source(void)
{
return (RCC_CFGR & RCC_CFGR_SWS) >> RCC_CFGR_SWS_SHIFT;
}
void rcc_wait_for_osc_ready(enum rcc_osc osc)
{
while (!rcc_is_osc_ready(osc));
}
void rcc_css_enable(void)
{
RCC_CR |= RCC_CR_CSSON;
}
void rcc_css_disable(void)
{
RCC_CR &= ~RCC_CR_CSSON;
}
/*---------------------------------------------------------------------------*/
/** @brief RCC Turn off an Oscillator.
Disable an oscillator and power off.
@note An oscillator cannot be turned off if it is selected as the system clock.
@note The LSE clock is in the backup domain and cannot be disabled until the
backup domain write protection has been removed (see
@ref pwr_disable_backup_domain_write_protect) or the backup domain has been
(see reset @ref rcc_backupdomain_reset).
@param[in] osc Oscillator ID
*/
void rcc_osc_off(enum rcc_osc osc)
{
switch (osc) {
case RCC_PLL3:
RCC_CR &= ~RCC_CR_PLL3ON;
break;
case RCC_PLL2:
RCC_CR &= ~RCC_CR_PLL2ON;
break;
case RCC_PLL1:
RCC_CR &= ~RCC_CR_PLL1ON;
break;
case RCC_HSE:
RCC_CR &= ~RCC_CR_HSEON;
break;
case RCC_SHSI:
RCC_CR &= ~RCC_CR_SHSION;
break;
case RCC_HSI48:
RCC_CR &= ~RCC_CR_HSI48ON;
break;
case RCC_HSI:
RCC_CR &= ~RCC_CR_HSION;
break;
case RCC_MSI:
RCC_CR &= ~RCC_CR_MSIKON;
break;
// TODO: Should we add MSIKER?
case RCC_MSIS:
RCC_CR &= ~RCC_CR_MSISON;
break;
default:
cm3_assert_not_reached();
break;
}
}
/*---------------------------------------------------------------------------*/
/** @brief RCC Turn on an Oscillator.
*
* Enable an oscillator and power on. Each oscillator requires an amount of
* time to settle to a usable state. Refer to datasheets for time delay
* information. A status flag is available to indicate when the oscillator
* becomes ready (see @ref rcc_osc_ready_int_flag and @ref
* rcc_wait_for_osc_ready).
*
* @param osc Oscillator ID
*/
void rcc_osc_on(enum rcc_osc osc)
{
switch (osc) {
case RCC_PLL3:
RCC_CR |= RCC_CR_PLL3ON;
break;
case RCC_PLL2:
RCC_CR |= RCC_CR_PLL2ON;
break;
case RCC_PLL1:
RCC_CR |= RCC_CR_PLL1ON;
break;
case RCC_HSE:
RCC_CR |= RCC_CR_HSEON;
break;
case RCC_SHSI:
RCC_CR |= RCC_CR_SHSION;
break;
case RCC_HSI48:
RCC_CR |= RCC_CR_HSI48ON;
break;
case RCC_HSI:
RCC_CR |= RCC_CR_HSION;
break;
case RCC_MSI:
RCC_CR |= RCC_CR_MSIKON;
break;
// TODO: Should we add MSIKER?
case RCC_MSIS:
RCC_CR |= RCC_CR_MSISON;
break;
default:
cm3_assert_not_reached();
break;
}
}
/*---------------------------------------------------------------------------*/
/** @brief Returns if the oscillator is ready.
*
* @param osc Oscillator ID
*/
bool rcc_is_osc_ready(enum rcc_osc osc)
{
switch (osc) {
case RCC_PLL3:
return RCC_CR & RCC_CR_PLL3RDY;
case RCC_PLL2:
return RCC_CR & RCC_CR_PLL2RDY;
case RCC_PLL1:
return RCC_CR & RCC_CR_PLL1RDY;
case RCC_HSE:
return RCC_CR & RCC_CR_HSERDY;
case RCC_SHSI:
return RCC_CR & RCC_CR_SHSIRDY;
case RCC_HSI48:
return RCC_CR & RCC_CR_HSI48RDY;
case RCC_HSI:
return RCC_CR & RCC_CR_HSIRDY;
case RCC_MSI:
return RCC_CR & RCC_CR_MSIKRDY;
case RCC_MSIS:
return RCC_CR & RCC_CR_MSISRDY;
default:
break;
}
return false;
}
/*---------------------------------------------------------------------------*/
/** @brief RCC Set the Source for the System Clock.
*
* @param clk Oscillator ID.
*/
void rcc_set_sysclk_source(enum rcc_osc clk)
{
uint32_t sw = 0x0;
switch (clk) {
case RCC_MSIS:
sw = RCC_CFGR_SW_SYSCLKSEL_MSIS;
break;
case RCC_HSI16:
sw = RCC_CFGR_SW_SYSCLKSEL_HSI16;
break;
case RCC_HSE:
sw = RCC_CFGR_SW_SYSCLKSEL_HSE;
break;
case RCC_PLL1:
sw = RCC_CFGR_SW_SYSCLKSEL_PLL;
break;
default:
cm3_assert_not_reached();
break;
}
sw <<= RCC_CFGR_SW_SYSCLKSEL_SHIFT;
RCC_CFGR = (RCC_CFGR & ~(RCC_CFGR_SW_SYSCLKSEL_MASK << RCC_CFGR_SW_SYSCLKSEL_SHIFT)) | sw;
}
/**
* @brief Set the peripheral clock source
* @param periph peripheral of choice, eg XXX_BASE
* @param sel periphral clock source
*/
void rcc_set_peripheral_clk_sel(uint32_t periph, uint32_t sel) {
volatile uint32_t *reg32;
uint32_t shift;
uint32_t mask;
switch (periph) {
case USART1_BASE:
reg32 = &RCC_CCIPR1;
shift = RCC_CCIPR1_USART1SEL_SHIFT;
mask = RCC_CCIPR_USARTxSEL_MASK;
break;
case USART2_BASE:
reg32 = &RCC_CCIPR1;
shift = RCC_CCIPR1_USART2SEL_SHIFT;
mask = RCC_CCIPR_USARTxSEL_MASK;
break;
case USART3_BASE:
reg32 = &RCC_CCIPR1;
shift = RCC_CCIPR1_USART3SEL_SHIFT;
mask = RCC_CCIPR_USARTxSEL_MASK;
break;
case USART4_BASE:
reg32 = &RCC_CCIPR1;
shift = RCC_CCIPR1_USART4SEL_SHIFT;
mask = RCC_CCIPR_USARTxSEL_MASK;
break;
case USART5_BASE:
reg32 = &RCC_CCIPR1;
shift = RCC_CCIPR1_USART5SEL_SHIFT;
mask = RCC_CCIPR_USARTxSEL_MASK;
break;
case USART6_BASE:
reg32 = &RCC_CCIPR2;
shift = RCC_CCIPR2_USART6SEL_SHIFT;
mask = RCC_CCIPR_USARTxSEL_MASK;
break;
default:
cm3_assert_not_reached();
break;
}
mask <<= shift;
sel <<= shift;
(*reg32) = ((*reg32) & ~mask) | sel;
}
static uint32_t rcc_get_usart_clksel_freq(uint32_t usart, uint8_t shift) {
uint8_t clksel;
if(usart == USART6_BASE) {
clksel = (RCC_CCIPR2 >> shift) & RCC_CCIPR_USARTxSEL_MASK;
} else {
clksel = (RCC_CCIPR1 >> shift) & RCC_CCIPR_USARTxSEL_MASK;
}
switch (clksel) {
case RCC_CCIPR_USARTxSEL_PCLKx:
if(usart == USART1_BASE) {
return rcc_apb2_frequency;
}
return rcc_apb1_frequency;
case RCC_CCIPR_USARTxSEL_SYSCLK:
return rcc_ahb_frequency;
case RCC_CCIPR_USARTxSEL_HSI16:
return RCC_DEFAULT_HSI16_FREQUENCY;
case RCC_CCIPR_USARTxSEL_LSE:
return RCC_DEFAULT_LSE_FREQUENCY;
default:
cm3_assert_not_reached();
break;
}
return 0;
}
/*---------------------------------------------------------------------------*/
/** @brief Get the peripheral clock speed for the USART at base specified.
* @param usart Base address of USART to get clock frequency for.
*/
uint32_t rcc_get_usart_clk_freq(uint32_t usart)
{
switch (usart)
{
case USART1_BASE:
return rcc_get_usart_clksel_freq(usart, RCC_CCIPR1_USART1SEL_SHIFT);
case USART2_BASE:
return rcc_get_usart_clksel_freq(usart, RCC_CCIPR1_USART2SEL_SHIFT);
case USART3_BASE:
return rcc_get_usart_clksel_freq(usart, RCC_CCIPR1_USART3SEL_SHIFT);
case USART4_BASE:
return rcc_get_usart_clksel_freq(usart, RCC_CCIPR1_USART4SEL_SHIFT);
case USART5_BASE:
return rcc_get_usart_clksel_freq(usart, RCC_CCIPR1_USART5SEL_SHIFT);
case USART6_BASE:
return rcc_get_usart_clksel_freq(usart, RCC_CCIPR2_USART6SEL_SHIFT);
default:
break;
}
cm3_assert_not_reached();
return 0;
}
/**@}*/