OpenRTX/platform/mcu/STM32F4xx/drivers/rcc.c

70 wiersze
2.6 KiB
C

/***************************************************************************
* Copyright (C) 2024 - 2025 by Federico Amedeo Izzo IU2NUO, *
* Niccolò Izzo IU2KIN *
* Frederik Saraci IU2NRO *
* Silvano Seva IU2KWO *
* Morgan Diepart ON4MOD *
* *
* This program is free software; you can redistribute it and/or modify *
* it under the terms of the GNU General Public License as published by *
* the Free Software Foundation; either version 3 of the License, or *
* (at your option) any later version. *
* *
* This program 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 General Public License for more details. *
* *
* You should have received a copy of the GNU General Public License *
* along with this program; if not, see <http://www.gnu.org/licenses/> *
***************************************************************************/
#include <stm32f4xx.h>
#include <stdint.h>
#include "rcc.h"
static uint32_t busClockFreq[PERIPH_BUS_NUM] = {0};
static void updateBusClockFreq(const uint8_t bus)
{
uint32_t preBits;
uint32_t clkDiv = 1;
switch(bus)
{
case PERIPH_BUS_AHB:
preBits = (RCC->CFGR >> 4) & 0x0F;
if((preBits & 0x08) != 0)
clkDiv = 1 << ((preBits & 0x07) + 1);
break;
case PERIPH_BUS_APB1:
preBits = (RCC->CFGR >> 10) & 0x07;
if((preBits & 0x04) != 0)
clkDiv = 1 << ((preBits & 0x03) + 1);
break;
case PERIPH_BUS_APB2:
preBits = (RCC->CFGR >> 13) & 0x07;
if((preBits & 0x04) != 0)
clkDiv = 1 << ((preBits & 0x03) + 1);
break;
default:
break;
}
busClockFreq[bus] = SystemCoreClock / clkDiv;
}
uint32_t rcc_getBusClock(const uint8_t bus)
{
if(bus >= PERIPH_BUS_NUM)
return 0;
if(busClockFreq[bus] == 0)
updateBusClockFreq(bus);
return busClockFreq[bus];
}