Karl Palsson 08aac020ad stm32: rcc: provide async routines for osc checks
Start providing async routines for all blocking routines, to make it
easier to use libopencm3 in some RTOS environments.  This is not in
anyway intended to be complete, this just covers a single blocking
routine, rcc_wait_for_osc_ready.  Documentation added to the top level,
and provided for all stm32 families.
2016-08-18 23:41:04 +00:00

423 lines
8.6 KiB
C

/** @defgroup rcc_file RCC
*
* @ingroup STM32F2xx
*
* @section rcc_f2_api_ex Reset and Clock Control API.
*
* @brief <b>libopencm3 STM32F2xx Reset and Clock Control</b>
*
* @author @htmlonly &copy; @endhtmlonly 2013 Frantisek Burian <BuFran at seznam.cz>
*
* @date 18 Jun 2013
*
* This library supports the Reset and Clock Control System in the STM32 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>
#include <libopencm3/stm32/flash.h>
/**@{*/
/* Set the default clock frequencies after reset. */
uint32_t rcc_ahb_frequency = 16000000;
uint32_t rcc_apb1_frequency = 16000000;
uint32_t rcc_apb2_frequency = 16000000;
const struct rcc_clock_scale rcc_hse_8mhz_3v3[RCC_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_ACR_ICE | FLASH_ACR_DCE |
FLASH_ACR_LATENCY_3WS,
.apb1_frequency = 30000000,
.apb2_frequency = 60000000,
},
};
void rcc_osc_ready_int_clear(enum rcc_osc osc)
{
switch (osc) {
case RCC_PLL:
RCC_CIR |= RCC_CIR_PLLRDYC;
break;
case RCC_HSE:
RCC_CIR |= RCC_CIR_HSERDYC;
break;
case RCC_HSI:
RCC_CIR |= RCC_CIR_HSIRDYC;
break;
case RCC_LSE:
RCC_CIR |= RCC_CIR_LSERDYC;
break;
case RCC_LSI:
RCC_CIR |= RCC_CIR_LSIRDYC;
break;
}
}
void rcc_osc_ready_int_enable(enum rcc_osc osc)
{
switch (osc) {
case RCC_PLL:
RCC_CIR |= RCC_CIR_PLLRDYIE;
break;
case RCC_HSE:
RCC_CIR |= RCC_CIR_HSERDYIE;
break;
case RCC_HSI:
RCC_CIR |= RCC_CIR_HSIRDYIE;
break;
case RCC_LSE:
RCC_CIR |= RCC_CIR_LSERDYIE;
break;
case RCC_LSI:
RCC_CIR |= RCC_CIR_LSIRDYIE;
break;
}
}
void rcc_osc_ready_int_disable(enum rcc_osc osc)
{
switch (osc) {
case RCC_PLL:
RCC_CIR &= ~RCC_CIR_PLLRDYIE;
break;
case RCC_HSE:
RCC_CIR &= ~RCC_CIR_HSERDYIE;
break;
case RCC_HSI:
RCC_CIR &= ~RCC_CIR_HSIRDYIE;
break;
case RCC_LSE:
RCC_CIR &= ~RCC_CIR_LSERDYIE;
break;
case RCC_LSI:
RCC_CIR &= ~RCC_CIR_LSIRDYIE;
break;
}
}
int rcc_osc_ready_int_flag(enum rcc_osc osc)
{
switch (osc) {
case RCC_PLL:
return ((RCC_CIR & RCC_CIR_PLLRDYF) != 0);
break;
case RCC_HSE:
return ((RCC_CIR & RCC_CIR_HSERDYF) != 0);
break;
case RCC_HSI:
return ((RCC_CIR & RCC_CIR_HSIRDYF) != 0);
break;
case RCC_LSE:
return ((RCC_CIR & RCC_CIR_LSERDYF) != 0);
break;
case RCC_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);
}
bool rcc_is_osc_ready(enum rcc_osc osc)
{
switch (osc) {
case RCC_PLL:
return (RCC_CR & RCC_CR_PLLRDY);
case RCC_HSE:
return (RCC_CR & RCC_CR_HSERDY);
case RCC_HSI:
return (RCC_CR & RCC_CR_HSIRDY);
case RCC_LSE:
return (RCC_BDCR & RCC_BDCR_LSERDY);
case RCC_LSI:
return (RCC_CSR & RCC_CSR_LSIRDY);
}
return false;
}
void rcc_wait_for_osc_ready(enum rcc_osc osc)
{
while (!rcc_is_osc_ready(osc));
}
void rcc_wait_for_sysclk_status(enum rcc_osc osc)
{
switch (osc) {
case RCC_PLL:
while (((RCC_CFGR >> RCC_CFGR_SWS_SHIFT) & RCC_CFGR_SWS_MASK) !=
RCC_CFGR_SWS_PLL);
break;
case RCC_HSE:
while (((RCC_CFGR >> RCC_CFGR_SWS_SHIFT) & RCC_CFGR_SWS_MASK) !=
RCC_CFGR_SWS_HSE);
break;
case RCC_HSI:
while (((RCC_CFGR >> RCC_CFGR_SWS_SHIFT) & RCC_CFGR_SWS_MASK) !=
RCC_CFGR_SWS_HSI);
break;
default:
/* Shouldn't be reached. */
break;
}
}
void rcc_osc_on(enum rcc_osc osc)
{
switch (osc) {
case RCC_PLL:
RCC_CR |= RCC_CR_PLLON;
break;
case RCC_HSE:
RCC_CR |= RCC_CR_HSEON;
break;
case RCC_HSI:
RCC_CR |= RCC_CR_HSION;
break;
case RCC_LSE:
RCC_BDCR |= RCC_BDCR_LSEON;
break;
case RCC_LSI:
RCC_CSR |= RCC_CSR_LSION;
break;
}
}
void rcc_osc_off(enum rcc_osc osc)
{
switch (osc) {
case RCC_PLL:
RCC_CR &= ~RCC_CR_PLLON;
break;
case RCC_HSE:
RCC_CR &= ~RCC_CR_HSEON;
break;
case RCC_HSI:
RCC_CR &= ~RCC_CR_HSION;
break;
case RCC_LSE:
RCC_BDCR &= ~RCC_BDCR_LSEON;
break;
case RCC_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(enum rcc_osc osc)
{
switch (osc) {
case RCC_HSE:
RCC_CR |= RCC_CR_HSEBYP;
break;
case RCC_LSE:
RCC_BDCR |= RCC_BDCR_LSEBYP;
break;
case RCC_PLL:
case RCC_HSI:
case RCC_LSI:
/* Do nothing, only HSE/LSE allowed here. */
break;
}
}
void rcc_osc_bypass_disable(enum rcc_osc osc)
{
switch (osc) {
case RCC_HSE:
RCC_CR &= ~RCC_CR_HSEBYP;
break;
case RCC_LSE:
RCC_BDCR &= ~RCC_BDCR_LSEBYP;
break;
case RCC_PLL:
case RCC_HSI:
case RCC_LSI:
/* 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_source(uint32_t pllsrc)
{
uint32_t reg32;
reg32 = RCC_PLLCFGR;
reg32 &= ~(1 << 22);
RCC_PLLCFGR = (reg32 | (pllsrc << 22));
}
void rcc_set_ppre2(uint32_t ppre2)
{
uint32_t reg32;
reg32 = RCC_CFGR;
reg32 &= ~((1 << 13) | (1 << 14) | (1 << 15));
RCC_CFGR = (reg32 | (ppre2 << 13));
}
void rcc_set_ppre1(uint32_t ppre1)
{
uint32_t reg32;
reg32 = RCC_CFGR;
reg32 &= ~((1 << 10) | (1 << 11) | (1 << 12));
RCC_CFGR = (reg32 | (ppre1 << 10));
}
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_CFGR;
reg32 &= ~((1 << 16) | (1 << 17) | (1 << 18) | (1 << 19) | (1 << 20));
RCC_CFGR = (reg32 | (rtcpre << 16));
}
void rcc_set_main_pll_hsi(uint32_t pllm, uint32_t plln, uint32_t pllp,
uint32_t 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(uint32_t pllm, uint32_t plln, uint32_t pllp,
uint32_t 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);
}
uint32_t 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 struct rcc_clock_scale *clock)
{
/* Enable internal high-speed oscillator. */
rcc_osc_on(RCC_HSI);
rcc_wait_for_osc_ready(RCC_HSI);
/* Select HSI as SYSCLK source. */
rcc_set_sysclk_source(RCC_CFGR_SW_HSI);
/* Enable external high-speed oscillator 8MHz. */
rcc_osc_on(RCC_HSE);
rcc_wait_for_osc_ready(RCC_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(RCC_PLL);
rcc_wait_for_osc_ready(RCC_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(RCC_PLL);
/* Set the peripheral clock frequencies used. */
rcc_apb1_frequency = clock->apb1_frequency;
rcc_apb2_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;
}
/**@}*/