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Diffstat (limited to 'libmaple/stm32f1/rcc.c')
-rw-r--r-- | libmaple/stm32f1/rcc.c | 205 |
1 files changed, 205 insertions, 0 deletions
diff --git a/libmaple/stm32f1/rcc.c b/libmaple/stm32f1/rcc.c new file mode 100644 index 0000000..c40d52f --- /dev/null +++ b/libmaple/stm32f1/rcc.c @@ -0,0 +1,205 @@ +/****************************************************************************** + * The MIT License + * + * Copyright (c) 2010 Perry Hung. + * Copyright (c) 2011 LeafLabs, LLC. + * + * Permission is hereby granted, free of charge, to any person + * obtaining a copy of this software and associated documentation + * files (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, + * modify, merge, publish, distribute, sublicense, and/or sell copies + * of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + *****************************************************************************/ + +/** + * @file libmaple/stm32f1/rcc.c + * @brief STM32F1 RCC routines. + */ + +#include <libmaple/rcc.h> +#include <libmaple/libmaple.h> +#include <libmaple/bitband.h> + +struct rcc_dev_info { + const rcc_clk_domain clk_domain; + const uint8 line_num; +}; + +#define APB1 RCC_APB1 +#define APB2 RCC_APB2 +#define AHB RCC_AHB + +/* Device descriptor table, maps rcc_clk_id onto bus and enable/reset + * register bit numbers. */ +static const struct rcc_dev_info rcc_dev_table[] = { + [RCC_GPIOA] = { .clk_domain = APB2, .line_num = 2 }, + [RCC_GPIOB] = { .clk_domain = APB2, .line_num = 3 }, + [RCC_GPIOC] = { .clk_domain = APB2, .line_num = 4 }, + [RCC_GPIOD] = { .clk_domain = APB2, .line_num = 5 }, + [RCC_AFIO] = { .clk_domain = APB2, .line_num = 0 }, + [RCC_ADC1] = { .clk_domain = APB2, .line_num = 9 }, + [RCC_ADC2] = { .clk_domain = APB2, .line_num = 10 }, + [RCC_ADC3] = { .clk_domain = APB2, .line_num = 15 }, + [RCC_USART1] = { .clk_domain = APB2, .line_num = 14 }, + [RCC_USART2] = { .clk_domain = APB1, .line_num = 17 }, + [RCC_USART3] = { .clk_domain = APB1, .line_num = 18 }, + [RCC_TIMER1] = { .clk_domain = APB2, .line_num = 11 }, + [RCC_TIMER2] = { .clk_domain = APB1, .line_num = 0 }, + [RCC_TIMER3] = { .clk_domain = APB1, .line_num = 1 }, + [RCC_TIMER4] = { .clk_domain = APB1, .line_num = 2 }, + [RCC_SPI1] = { .clk_domain = APB2, .line_num = 12 }, + [RCC_SPI2] = { .clk_domain = APB1, .line_num = 14 }, + [RCC_DMA1] = { .clk_domain = AHB, .line_num = 0 }, + [RCC_PWR] = { .clk_domain = APB1, .line_num = 28}, + [RCC_BKP] = { .clk_domain = APB1, .line_num = 27}, + [RCC_I2C1] = { .clk_domain = APB1, .line_num = 21 }, + [RCC_I2C2] = { .clk_domain = APB1, .line_num = 22 }, + [RCC_CRC] = { .clk_domain = AHB, .line_num = 6}, + [RCC_FLITF] = { .clk_domain = AHB, .line_num = 4}, + [RCC_SRAM] = { .clk_domain = AHB, .line_num = 2}, + [RCC_USB] = { .clk_domain = APB1, .line_num = 23}, +#if defined(STM32_HIGH_DENSITY) || defined(STM32_XL_DENSITY) + [RCC_GPIOE] = { .clk_domain = APB2, .line_num = 6 }, + [RCC_GPIOF] = { .clk_domain = APB2, .line_num = 7 }, + [RCC_GPIOG] = { .clk_domain = APB2, .line_num = 8 }, + [RCC_UART4] = { .clk_domain = APB1, .line_num = 19 }, + [RCC_UART5] = { .clk_domain = APB1, .line_num = 20 }, + [RCC_TIMER5] = { .clk_domain = APB1, .line_num = 3 }, + [RCC_TIMER6] = { .clk_domain = APB1, .line_num = 4 }, + [RCC_TIMER7] = { .clk_domain = APB1, .line_num = 5 }, + [RCC_TIMER8] = { .clk_domain = APB2, .line_num = 13 }, + [RCC_FSMC] = { .clk_domain = AHB, .line_num = 8 }, + [RCC_DAC] = { .clk_domain = APB1, .line_num = 29 }, + [RCC_DMA2] = { .clk_domain = AHB, .line_num = 1 }, + [RCC_SDIO] = { .clk_domain = AHB, .line_num = 10 }, + [RCC_SPI3] = { .clk_domain = APB1, .line_num = 15 }, +#endif +#ifdef STM32_XL_DENSITY + [RCC_TIMER9] = { .clk_domain = APB2, .line_num = 19 }, + [RCC_TIMER10] = { .clk_domain = APB2, .line_num = 20 }, + [RCC_TIMER11] = { .clk_domain = APB2, .line_num = 21 }, + [RCC_TIMER12] = { .clk_domain = APB1, .line_num = 6 }, + [RCC_TIMER13] = { .clk_domain = APB1, .line_num = 7 }, + [RCC_TIMER14] = { .clk_domain = APB1, .line_num = 8 }, +#endif +}; + +/** + * @brief Initialize the clock control system. Initializes the system + * clock source to use the PLL driven by an external oscillator + * @param sysclk_src system clock source, must be PLL + * @param pll_src pll clock source, must be HSE + * @param pll_mul pll multiplier + */ +void rcc_clk_init(rcc_sysclk_src sysclk_src, + rcc_pllsrc pll_src, + rcc_pll_multiplier pll_mul) { + uint32 cfgr = 0; + uint32 cr; + + /* Assume that we're going to clock the chip off the PLL, fed by + * the HSE */ + ASSERT(sysclk_src == RCC_CLKSRC_PLL && + pll_src == RCC_PLLSRC_HSE); + + RCC_BASE->CFGR = pll_src | pll_mul; + + /* Turn on the HSE */ + cr = RCC_BASE->CR; + cr |= RCC_CR_HSEON; + RCC_BASE->CR = cr; + while (!(RCC_BASE->CR & RCC_CR_HSERDY)) + ; + + /* Now the PLL */ + cr |= RCC_CR_PLLON; + RCC_BASE->CR = cr; + while (!(RCC_BASE->CR & RCC_CR_PLLRDY)) + ; + + /* Finally, let's switch over to the PLL */ + cfgr &= ~RCC_CFGR_SW; + cfgr |= RCC_CFGR_SW_PLL; + RCC_BASE->CFGR = cfgr; + while ((RCC_BASE->CFGR & RCC_CFGR_SWS) != RCC_CFGR_SWS_PLL) + ; +} + +/** + * @brief Turn on the clock line on a peripheral + * @param id Clock ID of the peripheral to turn on. + */ +void rcc_clk_enable(rcc_clk_id id) { + static const __io uint32* enable_regs[] = { + [APB1] = &RCC_BASE->APB1ENR, + [APB2] = &RCC_BASE->APB2ENR, + [AHB] = &RCC_BASE->AHBENR, + }; + + rcc_clk_domain clk_domain = rcc_dev_clk(id); + __io uint32* enr = (__io uint32*)enable_regs[clk_domain]; + uint8 lnum = rcc_dev_table[id].line_num; + + bb_peri_set_bit(enr, lnum, 1); +} + +/** + * @brief Reset a peripheral. + * @param id Clock ID of the peripheral to reset. + */ +void rcc_reset_dev(rcc_clk_id id) { + static const __io uint32* reset_regs[] = { + [APB1] = &RCC_BASE->APB1RSTR, + [APB2] = &RCC_BASE->APB2RSTR, + }; + + rcc_clk_domain clk_domain = rcc_dev_clk(id); + __io void* addr = (__io void*)reset_regs[clk_domain]; + uint8 lnum = rcc_dev_table[id].line_num; + + bb_peri_set_bit(addr, lnum, 1); + bb_peri_set_bit(addr, lnum, 0); +} + +/** + * @brief Get a peripheral's clock domain + * @param id Clock ID of the peripheral whose clock domain to return + * @return Clock source for the given clock ID + */ +rcc_clk_domain rcc_dev_clk(rcc_clk_id id) { + return rcc_dev_table[id].clk_domain; +} + +/** + * @brief Set the divider on a peripheral prescaler + * @param prescaler prescaler to set + * @param divider prescaler divider + */ +void rcc_set_prescaler(rcc_prescaler prescaler, uint32 divider) { + static const uint32 masks[] = { + [RCC_PRESCALER_AHB] = RCC_CFGR_HPRE, + [RCC_PRESCALER_APB1] = RCC_CFGR_PPRE1, + [RCC_PRESCALER_APB2] = RCC_CFGR_PPRE2, + [RCC_PRESCALER_USB] = RCC_CFGR_USBPRE, + [RCC_PRESCALER_ADC] = RCC_CFGR_ADCPRE, + }; + + uint32 cfgr = RCC_BASE->CFGR; + cfgr &= ~masks[prescaler]; + cfgr |= divider; + RCC_BASE->CFGR = cfgr; +} |