mbed-os/targets/TARGET_Freescale/TARGET_K20XX/sleep.c

84 lines
3.2 KiB
C

/* mbed Microcontroller Library
* Copyright (c) 2006-2015 ARM Limited
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "sleep_api.h"
#include "cmsis.h"
//Normal wait mode
void hal_sleep(void)
{
SMC->PMPROT = SMC_PMPROT_AVLLS_MASK | SMC_PMPROT_ALLS_MASK | SMC_PMPROT_AVLP_MASK;
//Normal sleep mode for ARM core:
SCB->SCR = 0;
__WFI();
}
//Very low-power stop mode
void hal_deepsleep(void)
{
//Check if ADC is enabled and HS mode is set, if yes disable it (lowers power consumption by 60uA)
uint8_t ADC_HSC = 0;
if (SIM->SCGC6 & SIM_SCGC6_ADC0_MASK) {
if (ADC0->CFG2 & ADC_CFG2_ADHSC_MASK) {
ADC_HSC = 1;
ADC0->CFG2 &= ~(ADC_CFG2_ADHSC_MASK);
}
}
//Check if PLL/FLL is enabled:
uint32_t PLL_FLL_en = (MCG->C1 & MCG_C1_CLKS_MASK) == MCG_C1_CLKS(0);
SMC->PMPROT = SMC_PMPROT_AVLLS_MASK | SMC_PMPROT_ALLS_MASK | SMC_PMPROT_AVLP_MASK;
SMC->PMCTRL = SMC_PMCTRL_STOPM(2);
//Deep sleep for ARM core:
SCB->SCR = 1<<SCB_SCR_SLEEPDEEP_Pos;
__WFI();
//Switch back to PLL as clock source if needed
//The interrupt that woke up the device will run at reduced speed
if (PLL_FLL_en) {
#if defined (TARGET_K20D50M)
if (MCG->C6 & (1<<MCG_C6_PLLS_SHIFT) != 0) /* If PLL */
while((MCG->S & MCG_S_LOCK0_MASK) == 0x00U); /* Wait until locked */
MCG->C1 &= ~MCG_C1_CLKS_MASK;
#else
// MCG->C1: CLKS=2,FRDIV=3,IREFS=0,IRCLKEN=1,IREFSTEN=0
MCG->C1 = MCG_C1_CLKS(2) | MCG_C1_FRDIV(3) | MCG_C1_IRCLKEN_MASK;
// MCG->C6: LOLIE=0,PLLS=0,CME=0,VDIV0=0
MCG->C6 = MCG_C6_VDIV0(0);
while((MCG->S & MCG_S_OSCINIT0_MASK) == 0u) { } // Check that the oscillator is running
while((MCG->S & 0x0Cu) != 0x08u) { } // Wait until external reference clock is selected as MCG output
// MCG->C5: PLLCLKEN=0,PLLSTEN=0,PRDIV0=3
MCG->C5 = MCG_C5_PRDIV0(5);
// MCG->C6: LOLIE=0,PLLS=1,CME=0,VDIV0=3
MCG->C6 = MCG_C6_PLLS_MASK | MCG_C6_VDIV0(3);
while((MCG->S & 0x0Cu) != 0x08u) { } // Wait until external reference clock is selected as MCG output
while((MCG->S & MCG_S_PLLST_MASK) == 0u) { } // Wait until the source of the PLLS clock has switched to the PLL
while((MCG->S & MCG_S_LOCK0_MASK) == 0u) { } // Wait until locked
// MCG->C1: CLKS=0,FRDIV=2,IREFS=0,IRCLKEN=1,IREFSTEN=0
MCG->C1 = MCG_C1_FRDIV(2) | MCG_C1_IRCLKEN_MASK;;
while((MCG->S & 0x0Cu) != 0x0Cu) { } // Wait until output of the PLL is selected
while((MCG->S & MCG_S_LOCK0_MASK) == 0u) { } // Wait until locked
#endif
}
if (ADC_HSC) {
ADC0->CFG2 |= (ADC_CFG2_ADHSC_MASK);
}
}