nuttx/arch/arm/src/stm32/stm32_pwr.c

144 lines
5.1 KiB
C

/************************************************************************************
* arch/arm/src/stm32/stm32_pwr.c
*
* Copyright (C) 2011 Uros Platise. All rights reserved.
* Copyright (C) 2013 Gregory Nutt. All rights reserved.
* Authors: Uros Platise <uros.platise@isotel.eu>
* Gregory Nutt <gnutt@nuttx.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
************************************************************************************/
/************************************************************************************
* Included Files
************************************************************************************/
#include <nuttx/config.h>
#include <nuttx/arch.h>
#include <stdint.h>
#include <errno.h>
#include "up_arch.h"
#include "stm32_pwr.h"
#if defined(CONFIG_STM32_PWR)
/************************************************************************************
* Pre-processor Definitions
************************************************************************************/
/************************************************************************************
* Private Functions
************************************************************************************/
static inline uint16_t stm32_pwr_getreg(uint8_t offset)
{
return (uint16_t)getreg32(STM32_PWR_BASE + (uint32_t)offset);
}
static inline void stm32_pwr_putreg(uint8_t offset, uint16_t value)
{
putreg32((uint32_t)value, STM32_PWR_BASE + (uint32_t)offset);
}
static inline void stm32_pwr_modifyreg(uint8_t offset, uint16_t clearbits, uint16_t setbits)
{
modifyreg32(STM32_PWR_BASE + (uint32_t)offset, (uint32_t)clearbits, (uint32_t)setbits);
}
/************************************************************************************
* Public Functions
************************************************************************************/
/************************************************************************************
* Name: stm32_pwr_enablebkp
*
* Description:
* Enables access to the backup domain (RTC registers, RTC backup data registers
* and backup SRAM).
*
* Input Parameters:
* None
*
* Returned Values:
* None
*
************************************************************************************/
void stm32_pwr_enablebkp(void)
{
stm32_pwr_modifyreg(STM32_PWR_CR_OFFSET, 0, PWR_CR_DBP);
}
/************************************************************************************
* Name: stm32_pwr_setvos
*
* Description:
* Set voltage scaling for EneryLite devices.
*
* Input Parameters:
* vos - Properly aligned voltage scaling select bits for the PWR_CR register.
*
* Returned Values:
* None
*
* Assumptions:
* At present, this function is called only from initialization logic. If used
* for any other purpose that protection to assure that its operation is atomic
* will be required.
*
************************************************************************************/
#ifdef CONFIG_STM32_ENERGYLITE
void stm32_pwr_setvos(uint16_t vos)
{
uint16_t regval;
/* The following sequence is required to program the voltage regulator ranges:
* 1. Check VDD to identify which ranges are allowed...
* 2. Poll VOSF bit of in PWR_CSR. Wait until it is reset to 0.
* 3. Configure the voltage scaling range by setting the VOS bits in the PWR_CR
* register.
* 4. Poll VOSF bit of in PWR_CSR register. Wait until it is reset to 0.
*/
while((stm32_pwr_getreg(STM32_PWR_CSR_OFFSET) & PWR_CSR_VOSF) != 0);
regval = stm32_pwr_getreg(STM32_PWR_CR_OFFSET);
regval &= ~PWR_CR_VOS_MASK;
regval |= (vos & PWR_CR_VOS_MASK);
stm32_pwr_putreg(STM32_PWR_CR_OFFSET, regval);
while((stm32_pwr_getreg(STM32_PWR_CSR_OFFSET) & PWR_CSR_VOSF) != 0);
}
#endif
#endif /* CONFIG_STM32_PWR */