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-rw-r--r--libopencm3/lib/stm32/l1/rcc.c534
1 files changed, 534 insertions, 0 deletions
diff --git a/libopencm3/lib/stm32/l1/rcc.c b/libopencm3/lib/stm32/l1/rcc.c
new file mode 100644
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+++ b/libopencm3/lib/stm32/l1/rcc.c
@@ -0,0 +1,534 @@
+/*
+ * 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>
+ * Copyright (C) 2012 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/>.
+ * Based on the F4 code...
+ */
+
+#include <libopencm3/stm32/rcc.h>
+#include <libopencm3/stm32/flash.h>
+#include <libopencm3/stm32/pwr.h>
+
+/* Set the default ppre1 and ppre2 peripheral clock frequencies after reset. */
+uint32_t rcc_ppre1_frequency = 2097000;
+uint32_t rcc_ppre2_frequency = 2097000;
+
+const clock_scale_t clock_config[CLOCK_CONFIG_END] = {
+ { /* 24MHz PLL from HSI */
+ .pll_source = RCC_CFGR_PLLSRC_HSI_CLK,
+ .pll_mul = RCC_CFGR_PLLMUL_MUL3,
+ .pll_div = RCC_CFGR_PLLDIV_DIV2,
+ .hpre = RCC_CFGR_HPRE_SYSCLK_NODIV,
+ .ppre1 = RCC_CFGR_PPRE1_HCLK_NODIV,
+ .ppre2 = RCC_CFGR_PPRE2_HCLK_NODIV,
+ .voltage_scale = RANGE1,
+ .flash_config = FLASH_ACR_LATENCY_1WS,
+ .apb1_frequency = 24000000,
+ .apb2_frequency = 24000000,
+ },
+ { /* 32MHz PLL from HSI */
+ .pll_source = RCC_CFGR_PLLSRC_HSI_CLK,
+ .pll_mul = RCC_CFGR_PLLMUL_MUL6,
+ .pll_div = RCC_CFGR_PLLDIV_DIV3,
+ .hpre = RCC_CFGR_HPRE_SYSCLK_NODIV,
+ .ppre1 = RCC_CFGR_PPRE1_HCLK_NODIV,
+ .ppre2 = RCC_CFGR_PPRE2_HCLK_NODIV,
+ .voltage_scale = RANGE1,
+ .flash_config = FLASH_ACR_LATENCY_1WS,
+ .apb1_frequency = 32000000,
+ .apb2_frequency = 32000000,
+ },
+ { /* 16MHz HSI raw */
+ .hpre = RCC_CFGR_HPRE_SYSCLK_NODIV,
+ .ppre1 = RCC_CFGR_PPRE1_HCLK_NODIV,
+ .ppre2 = RCC_CFGR_PPRE2_HCLK_NODIV,
+ .voltage_scale = RANGE1,
+ .flash_config = FLASH_ACR_LATENCY_0WS,
+ .apb1_frequency = 16000000,
+ .apb2_frequency = 16000000,
+ },
+ { /* 4MHz HSI raw */
+ .hpre = RCC_CFGR_HPRE_SYSCLK_DIV4,
+ .ppre1 = RCC_CFGR_PPRE1_HCLK_NODIV,
+ .ppre2 = RCC_CFGR_PPRE2_HCLK_NODIV,
+ .voltage_scale = RANGE1,
+ .flash_config = FLASH_ACR_LATENCY_0WS,
+ .apb1_frequency = 4000000,
+ .apb2_frequency = 4000000,
+ },
+ { /* 4MHz MSI raw */
+ .hpre = RCC_CFGR_HPRE_SYSCLK_NODIV,
+ .ppre1 = RCC_CFGR_PPRE1_HCLK_NODIV,
+ .ppre2 = RCC_CFGR_PPRE2_HCLK_NODIV,
+ .voltage_scale = RANGE1,
+ .flash_config = FLASH_ACR_LATENCY_0WS,
+ .apb1_frequency = 4194000,
+ .apb2_frequency = 4194000,
+ .msi_range = RCC_ICSCR_MSIRANGE_4MHZ,
+ },
+ { /* 2MHz MSI raw */
+ .hpre = RCC_CFGR_HPRE_SYSCLK_NODIV,
+ .ppre1 = RCC_CFGR_PPRE1_HCLK_NODIV,
+ .ppre2 = RCC_CFGR_PPRE2_HCLK_NODIV,
+ .voltage_scale = RANGE1,
+ .flash_config = FLASH_ACR_LATENCY_0WS,
+ .apb1_frequency = 2097000,
+ .apb2_frequency = 2097000,
+ .msi_range = RCC_ICSCR_MSIRANGE_2MHZ,
+ },
+};
+
+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;
+ case MSI:
+ RCC_CIR |= RCC_CIR_MSIRDYC;
+ 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;
+ case MSI:
+ RCC_CIR |= RCC_CIR_MSIRDYIE;
+ 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;
+ case MSI:
+ RCC_CIR &= ~RCC_CIR_MSIRDYIE;
+ 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;
+ case MSI:
+ return ((RCC_CIR & RCC_CIR_MSIRDYF) != 0);
+ break;
+ }
+
+ /* Shouldn't be reached. */
+ return -1;
+}
+
+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 MSI:
+ while ((RCC_CR & RCC_CR_MSIRDY) == 0);
+ break;
+ case LSE:
+ while ((RCC_CSR & RCC_CSR_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_SYSCLKSEL_PLLCLK);
+ break;
+ case HSE:
+ while ((RCC_CFGR & ((1 << 1) | (1 << 0))) !=
+ RCC_CFGR_SWS_SYSCLKSEL_HSECLK);
+ break;
+ case HSI:
+ while ((RCC_CFGR & ((1 << 1) | (1 << 0))) !=
+ RCC_CFGR_SWS_SYSCLKSEL_HSICLK);
+ break;
+ case MSI:
+ while ((RCC_CFGR & ((1 << 1) | (1 << 0))) !=
+ RCC_CFGR_SWS_SYSCLKSEL_MSICLK);
+ 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 MSI:
+ RCC_CR |= RCC_CR_MSION;
+ break;
+ case HSE:
+ RCC_CR |= RCC_CR_HSEON;
+ break;
+ case HSI:
+ RCC_CR |= RCC_CR_HSION;
+ break;
+ case LSE:
+ RCC_CSR |= RCC_CSR_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 MSI:
+ RCC_CR &= ~RCC_CR_MSION;
+ break;
+ case HSE:
+ RCC_CR &= ~RCC_CR_HSEON;
+ break;
+ case HSI:
+ RCC_CR &= ~RCC_CR_HSION;
+ break;
+ case LSE:
+ RCC_CSR &= ~RCC_CSR_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_CSR |= RCC_CSR_LSEBYP;
+ break;
+ case PLL:
+ case HSI:
+ case LSI:
+ case MSI:
+ /* 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_CSR &= ~RCC_CSR_LSEBYP;
+ break;
+ case PLL:
+ case HSI:
+ case LSI:
+ case MSI:
+ /* Do nothing, only HSE/LSE allowed here. */
+ break;
+ }
+}
+
+void rcc_set_sysclk_source(uint32_t clk)
+{
+ uint32_t reg32;
+
+ reg32 = RCC_CFGR;
+ reg32 &= ~((1 << 1) | (1 << 0));
+ RCC_CFGR = (reg32 | clk);
+}
+
+void rcc_set_pll_configuration(uint32_t source, uint32_t multiplier,
+ uint32_t divisor)
+{
+ uint32_t reg32;
+
+ reg32 = RCC_CFGR;
+ reg32 &= ~(RCC_CFGR_PLLDIV_MASK << RCC_CFGR_PLLDIV_SHIFT);
+ reg32 &= ~(RCC_CFGR_PLLMUL_MASK << RCC_CFGR_PLLMUL_SHIFT);
+ reg32 &= ~(1 << 16);
+ reg32 |= (source << 16);
+ reg32 |= (multiplier << RCC_CFGR_PLLMUL_SHIFT);
+ reg32 |= (divisor << RCC_CFGR_PLLDIV_SHIFT);
+ RCC_CFGR = reg32;
+}
+
+void rcc_set_pll_source(uint32_t pllsrc)
+{
+ uint32_t reg32;
+
+ reg32 = RCC_CFGR;
+ reg32 &= ~(1 << 16);
+ RCC_CFGR = (reg32 | (pllsrc << 16));
+}
+
+void rcc_set_ppre2(uint32_t ppre2)
+{
+ uint32_t reg32;
+
+ reg32 = RCC_CFGR;
+ reg32 &= ~((1 << 13) | (1 << 12) | (1 << 11));
+ RCC_CFGR = (reg32 | (ppre2 << 11));
+}
+
+void rcc_set_ppre1(uint32_t ppre1)
+{
+ uint32_t reg32;
+
+ reg32 = RCC_CFGR;
+ reg32 &= ~((1 << 10) | (1 << 9) | (1 << 8));
+ RCC_CFGR = (reg32 | (ppre1 << 8));
+}
+
+void rcc_set_hpre(uint32_t hpre)
+{
+ uint32_t reg32;
+
+ reg32 = RCC_CFGR;
+ reg32 &= ~((1 << 4) | (1 << 5) | (1 << 6) | (1 << 7));
+ RCC_CFGR = (reg32 | (hpre << 4));
+}
+
+void rcc_set_rtcpre(uint32_t rtcpre)
+{
+ uint32_t reg32;
+
+ reg32 = RCC_CR;
+ reg32 &= ~((1 << 30) | (1 << 29));
+ RCC_CR = (reg32 | (rtcpre << 29));
+}
+
+uint32_t rcc_system_clock_source(void)
+{
+ /* Return the clock source which is used as system clock. */
+ return (RCC_CFGR & 0x000c) >> 2;
+}
+
+void rcc_rtc_select_clock(uint32_t clock)
+{
+ RCC_CSR &= ~(RCC_CSR_RTCSEL_MASK << RCC_CSR_RTCSEL_SHIFT);
+ RCC_CSR |= (clock << RCC_CSR_RTCSEL_SHIFT);
+}
+
+void rcc_clock_setup_msi(const clock_scale_t *clock)
+{
+ /* Enable internal multi-speed oscillator. */
+
+ uint32_t reg = RCC_ICSCR;
+ reg &= ~(RCC_ICSCR_MSIRANGE_MASK << RCC_ICSCR_MSIRANGE_SHIFT);
+ reg |= (clock->msi_range << RCC_ICSCR_MSIRANGE_SHIFT);
+ RCC_ICSCR = reg;
+
+ rcc_osc_on(MSI);
+ rcc_wait_for_osc_ready(MSI);
+
+ /* Select MSI as SYSCLK source. */
+ rcc_set_sysclk_source(RCC_CFGR_SW_SYSCLKSEL_MSICLK);
+
+ /*
+ * 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_peripheral_enable_clock(&RCC_APB1ENR, RCC_APB1ENR_PWREN);
+ pwr_set_vos_scale(clock->voltage_scale);
+
+ /* I guess this should be in the settings? */
+ flash_64bit_enable();
+ flash_prefetch_enable();
+ /* Configure flash settings. */
+ flash_set_ws(clock->flash_config);
+
+ /* Set the peripheral clock frequencies used. */
+ rcc_ppre1_frequency = clock->apb1_frequency;
+ rcc_ppre2_frequency = clock->apb2_frequency;
+}
+
+void rcc_clock_setup_hsi(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_SYSCLKSEL_HSICLK);
+
+ /*
+ * 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_peripheral_enable_clock(&RCC_APB1ENR, RCC_APB1ENR_PWREN);
+ pwr_set_vos_scale(clock->voltage_scale);
+
+ /* I guess this should be in the settings? */
+ flash_64bit_enable();
+ flash_prefetch_enable();
+ /* Configure flash settings. */
+ flash_set_ws(clock->flash_config);
+
+ /* Set the peripheral clock frequencies used. */
+ rcc_ppre1_frequency = clock->apb1_frequency;
+ rcc_ppre2_frequency = clock->apb2_frequency;
+}
+
+void rcc_clock_setup_pll(const clock_scale_t *clock)
+{
+ /* Enable internal high-speed oscillator. */
+ rcc_osc_on(HSI);
+ rcc_wait_for_osc_ready(HSI);
+
+ /*
+ * 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_peripheral_enable_clock(&RCC_APB1ENR, RCC_APB1ENR_PWREN);
+ pwr_set_vos_scale(clock->voltage_scale);
+
+ /* I guess this should be in the settings? */
+ flash_64bit_enable();
+ flash_prefetch_enable();
+ /* Configure flash settings. */
+ flash_set_ws(clock->flash_config);
+
+ rcc_set_pll_configuration(clock->pll_source, clock->pll_mul,
+ clock->pll_div);
+
+ /* Enable PLL oscillator and wait for it to stabilize. */
+ rcc_osc_on(PLL);
+ rcc_wait_for_osc_ready(PLL);
+
+ /* Select PLL as SYSCLK source. */
+ rcc_set_sysclk_source(RCC_CFGR_SW_SYSCLKSEL_PLLCLK);
+
+ /* Set the peripheral clock frequencies used. */
+ rcc_ppre1_frequency = clock->apb1_frequency;
+ rcc_ppre2_frequency = clock->apb2_frequency;
+}