/* * This file is part of the libopencm3 project. * * Copyright (C) 2009 Federico Ruiz-Ugalde * Copyright (C) 2009 Uwe Hermann * Copyright (C) 2010 Thomas Otto * * 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 . */ #include #include #include /* Set the default ppre1 and ppre2 peripheral clock frequencies after reset. */ u32 rcc_ppre1_frequency = 16000000; u32 rcc_ppre2_frequency = 16000000; const clock_scale_t hse_8mhz_3v3[CLOCK_3V3_END] = { { /* 120MHz */ .pllm = 8, .plln = 240, .pllp = 2, .pllq = 5, .hpre = RCC_CFGR_HPRE_DIV_NONE, .ppre1 = RCC_CFGR_PPRE_DIV_4, .ppre2 = RCC_CFGR_PPRE_DIV_2, .flash_config = FLASH_ICE | FLASH_DCE | FLASH_LATENCY_3WS, .apb1_frequency = 30000000, .apb2_frequency = 60000000, }, }; void rcc_osc_ready_int_clear(osc_t osc) { switch (osc) { case PLL: RCC_CIR |= RCC_CIR_PLLRDYC; break; case HSE: RCC_CIR |= RCC_CIR_HSERDYC; break; case HSI: RCC_CIR |= RCC_CIR_HSIRDYC; break; case LSE: RCC_CIR |= RCC_CIR_LSERDYC; break; case LSI: RCC_CIR |= RCC_CIR_LSIRDYC; break; } } void rcc_osc_ready_int_enable(osc_t osc) { switch (osc) { case PLL: RCC_CIR |= RCC_CIR_PLLRDYIE; break; case HSE: RCC_CIR |= RCC_CIR_HSERDYIE; break; case HSI: RCC_CIR |= RCC_CIR_HSIRDYIE; break; case LSE: RCC_CIR |= RCC_CIR_LSERDYIE; break; case LSI: RCC_CIR |= RCC_CIR_LSIRDYIE; break; } } void rcc_osc_ready_int_disable(osc_t osc) { switch (osc) { case PLL: RCC_CIR &= ~RCC_CIR_PLLRDYIE; break; case HSE: RCC_CIR &= ~RCC_CIR_HSERDYIE; break; case HSI: RCC_CIR &= ~RCC_CIR_HSIRDYIE; break; case LSE: RCC_CIR &= ~RCC_CIR_LSERDYIE; break; case LSI: RCC_CIR &= ~RCC_CIR_LSIRDYIE; break; } } int rcc_osc_ready_int_flag(osc_t osc) { switch (osc) { case PLL: return ((RCC_CIR & RCC_CIR_PLLRDYF) != 0); break; case HSE: return ((RCC_CIR & RCC_CIR_HSERDYF) != 0); break; case HSI: return ((RCC_CIR & RCC_CIR_HSIRDYF) != 0); break; case LSE: return ((RCC_CIR & RCC_CIR_LSERDYF) != 0); break; case LSI: return ((RCC_CIR & RCC_CIR_LSIRDYF) != 0); break; } cm3_assert_not_reached(); } void rcc_css_int_clear(void) { RCC_CIR |= RCC_CIR_CSSC; } int rcc_css_int_flag(void) { return ((RCC_CIR & RCC_CIR_CSSF) != 0); } void rcc_wait_for_osc_ready(osc_t osc) { switch (osc) { case PLL: while ((RCC_CR & RCC_CR_PLLRDY) == 0); break; case HSE: while ((RCC_CR & RCC_CR_HSERDY) == 0); break; case HSI: while ((RCC_CR & RCC_CR_HSIRDY) == 0); break; case LSE: while ((RCC_BDCR & RCC_BDCR_LSERDY) == 0); break; case LSI: while ((RCC_CSR & RCC_CSR_LSIRDY) == 0); break; } } void rcc_wait_for_sysclk_status(osc_t osc) { switch (osc) { case PLL: while ((RCC_CFGR & ((1 << 1) | (1 << 0))) != RCC_CFGR_SWS_PLL); break; case HSE: while ((RCC_CFGR & ((1 << 1) | (1 << 0))) != RCC_CFGR_SWS_HSE); break; case HSI: while ((RCC_CFGR & ((1 << 1) | (1 << 0))) != RCC_CFGR_SWS_HSI); break; default: /* Shouldn't be reached. */ break; } } void rcc_osc_on(osc_t osc) { switch (osc) { case PLL: RCC_CR |= RCC_CR_PLLON; break; case HSE: RCC_CR |= RCC_CR_HSEON; break; case HSI: RCC_CR |= RCC_CR_HSION; break; case LSE: RCC_BDCR |= RCC_BDCR_LSEON; break; case LSI: RCC_CSR |= RCC_CSR_LSION; break; } } void rcc_osc_off(osc_t osc) { switch (osc) { case PLL: RCC_CR &= ~RCC_CR_PLLON; break; case HSE: RCC_CR &= ~RCC_CR_HSEON; break; case HSI: RCC_CR &= ~RCC_CR_HSION; break; case LSE: RCC_BDCR &= ~RCC_BDCR_LSEON; break; case LSI: RCC_CSR &= ~RCC_CSR_LSION; break; } } void rcc_css_enable(void) { RCC_CR |= RCC_CR_CSSON; } void rcc_css_disable(void) { RCC_CR &= ~RCC_CR_CSSON; } void rcc_osc_bypass_enable(osc_t osc) { switch (osc) { case HSE: RCC_CR |= RCC_CR_HSEBYP; break; case LSE: RCC_BDCR |= RCC_BDCR_LSEBYP; break; case PLL: case HSI: case LSI: /* Do nothing, only HSE/LSE allowed here. */ break; } } void rcc_osc_bypass_disable(osc_t osc) { switch (osc) { case HSE: RCC_CR &= ~RCC_CR_HSEBYP; break; case LSE: RCC_BDCR &= ~RCC_BDCR_LSEBYP; break; case PLL: case HSI: case LSI: /* Do nothing, only HSE/LSE allowed here. */ break; } } void rcc_peripheral_enable_clock(volatile u32 *reg, u32 en) { *reg |= en; } void rcc_peripheral_disable_clock(volatile u32 *reg, u32 en) { *reg &= ~en; } void rcc_peripheral_reset(volatile u32 *reg, u32 reset) { *reg |= reset; } void rcc_peripheral_clear_reset(volatile u32 *reg, u32 clear_reset) { *reg &= ~clear_reset; } void rcc_set_sysclk_source(u32 clk) { u32 reg32; reg32 = RCC_CFGR; reg32 &= ~((1 << 1) | (1 << 0)); RCC_CFGR = (reg32 | clk); } void rcc_set_pll_source(u32 pllsrc) { u32 reg32; reg32 = RCC_PLLCFGR; reg32 &= ~(1 << 22); RCC_PLLCFGR = (reg32 | (pllsrc << 22)); } void rcc_set_ppre2(u32 ppre2) { u32 reg32; reg32 = RCC_CFGR; reg32 &= ~((1 << 13) | (1 << 14) | (1 << 15)); RCC_CFGR = (reg32 | (ppre2 << 13)); } void rcc_set_ppre1(u32 ppre1) { u32 reg32; reg32 = RCC_CFGR; reg32 &= ~((1 << 10) | (1 << 11) | (1 << 12)); RCC_CFGR = (reg32 | (ppre1 << 10)); } void rcc_set_hpre(u32 hpre) { u32 reg32; reg32 = RCC_CFGR; reg32 &= ~((1 << 4) | (1 << 5) | (1 << 6) | (1 << 7)); RCC_CFGR = (reg32 | (hpre << 4)); } void rcc_set_rtcpre(u32 rtcpre) { u32 reg32; reg32 = RCC_CFGR; reg32 &= ~((1 << 16) | (1 << 17) | (1 << 18) | (1 << 19) | (1 << 20)); RCC_CFGR = (reg32 | (rtcpre << 16)); } void rcc_set_main_pll_hsi(u32 pllm, u32 plln, u32 pllp, u32 pllq) { RCC_PLLCFGR = (pllm << RCC_PLLCFGR_PLLM_SHIFT) | (plln << RCC_PLLCFGR_PLLN_SHIFT) | (((pllp >> 1) - 1) << RCC_PLLCFGR_PLLP_SHIFT) | (pllq << RCC_PLLCFGR_PLLQ_SHIFT); } void rcc_set_main_pll_hse(u32 pllm, u32 plln, u32 pllp, u32 pllq) { RCC_PLLCFGR = (pllm << RCC_PLLCFGR_PLLM_SHIFT) | (plln << RCC_PLLCFGR_PLLN_SHIFT) | (((pllp >> 1) - 1) << RCC_PLLCFGR_PLLP_SHIFT) | RCC_PLLCFGR_PLLSRC | (pllq << RCC_PLLCFGR_PLLQ_SHIFT); } u32 rcc_system_clock_source(void) { /* Return the clock source which is used as system clock. */ return ((RCC_CFGR & 0x000c) >> 2); } void rcc_clock_setup_hse_3v3(const clock_scale_t *clock) { /* Enable internal high-speed oscillator. */ rcc_osc_on(HSI); rcc_wait_for_osc_ready(HSI); /* Select HSI as SYSCLK source. */ rcc_set_sysclk_source(RCC_CFGR_SW_HSI); /* Enable external high-speed oscillator 8MHz. */ rcc_osc_on(HSE); rcc_wait_for_osc_ready(HSE); /* * Set prescalers for AHB, ADC, ABP1, ABP2. * Do this before touching the PLL (TODO: why?). */ rcc_set_hpre(clock->hpre); rcc_set_ppre1(clock->ppre1); rcc_set_ppre2(clock->ppre2); rcc_set_main_pll_hse(clock->pllm, clock->plln, clock->pllp, clock->pllq); /* Enable PLL oscillator and wait for it to stabilize. */ rcc_osc_on(PLL); rcc_wait_for_osc_ready(PLL); /* Configure flash settings. */ flash_set_ws(clock->flash_config); /* Select PLL as SYSCLK source. */ rcc_set_sysclk_source(RCC_CFGR_SW_PLL); /* Wait for PLL clock to be selected. */ rcc_wait_for_sysclk_status(PLL); /* Set the peripheral clock frequencies used. */ rcc_ppre1_frequency = clock->apb1_frequency; rcc_ppre2_frequency = clock->apb2_frequency; } void rcc_backupdomain_reset(void) { /* Set the backup domain software reset. */ RCC_BDCR |= RCC_BDCR_BDRST; /* Clear the backup domain software reset. */ RCC_BDCR &= ~RCC_BDCR_BDRST; }