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MIMXRT1050_EVK: Update lpticker implementation 

Use only the GPT module and avoid using RTC.

Signed-off-by: Mahesh Mahadevan <mahesh.mahadevan@nxp.com>
pull/7009/head
Mahesh Mahadevan 2018-05-17 04:58:16 -05:00 committed by Bartek Szatkowski
parent 3b7b0f1307
commit fb622a2081
2 changed files with 35 additions and 54 deletions
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87
targets/TARGET_NXP/TARGET_MCUXpresso_MCUS/TARGET_IMX/lp_ticker.c
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@ -1,5 +1,5 @@
/* mbed Microcontroller Library
* Copyright (c) 2016 ARM Limited
* Copyright (c) 2018 ARM Limited
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
@ -17,20 +17,24 @@
#if DEVICE_LPTICKER
#include "lp_ticker_api.h"
#include "fsl_snvs_hp.h"
#include "fsl_gpt.h"
#include "cmsis.h"
#include "rtc_api.h"
#define LOWFREQ_REF_CLK_HZ (32768)
const ticker_info_t* lp_ticker_get_info()
{
static const ticker_info_t info = {
32768, // 32kHz
32 // 32 bit counter
};
return &info;
}
static bool lp_ticker_inited = false;
static void gpt_isr(void)
{
GPT_ClearStatusFlags(GPT2, kGPT_OutputCompare1Flag);
GPT_StopTimer(GPT2);
GPT_DisableInterrupts(GPT2, kGPT_OutputCompare1InterruptEnable);
lp_ticker_irq_handler();
}
@ -41,71 +45,48 @@ void lp_ticker_init(void)
{
gpt_config_t gptConfig;
if (lp_ticker_inited) {
return;
}
lp_ticker_inited = true;
if (!lp_ticker_inited) {
/* Setup GPT */
GPT_GetDefaultConfig(&gptConfig);
/* Use 32kHz drive */
gptConfig.clockSource = kGPT_ClockSource_LowFreq;
gptConfig.enableFreeRun = true;
gptConfig.enableMode = false;
/* Setup low resolution clock - RTC */
if (!rtc_isenabled()) {
rtc_init();
GPT_Init(GPT2, &gptConfig);
GPT_EnableInterrupts(GPT2, kGPT_OutputCompare1InterruptEnable);
NVIC_ClearPendingIRQ(GPT2_IRQn);
NVIC_SetVector(GPT2_IRQn, (uint32_t)gpt_isr);
EnableIRQ(GPT2_IRQn);
GPT_StartTimer(GPT2);
lp_ticker_inited = true;
} else {
GPT_DisableInterrupts(GPT2, kGPT_OutputCompare1InterruptEnable);
}
/* Setup GPT */
GPT_GetDefaultConfig(&gptConfig);
/* Use 32kHz drive */
gptConfig.clockSource = kGPT_ClockSource_LowFreq;
GPT_Init(GPT2, &gptConfig);
GPT_EnableInterrupts(GPT2, kGPT_OutputCompare1InterruptEnable);
NVIC_ClearPendingIRQ(GPT2_IRQn);
NVIC_SetVector(GPT2_IRQn, (uint32_t)gpt_isr);
EnableIRQ(GPT2_IRQn);
}
/** Read the current counter
*
* @return The current timer's counter value in microseconds
* @return The current timer's counter value in ticks
*/
uint32_t lp_ticker_read(void)
{
uint32_t ticks = 0;
uint64_t tmp = 0;
if (!lp_ticker_inited) {
lp_ticker_init();
}
/* Do consecutive reads until value is correct */
do
{
ticks = tmp;
tmp = SNVS->HPRTCLR;
} while (tmp != ticks);
return COUNT_TO_USEC(ticks, LOWFREQ_REF_CLK_HZ);;
return GPT_GetCurrentTimerCount(GPT2);
}
/** Set interrupt for specified timestamp
*
* @param timestamp The time in microseconds to be set
* @param timestamp The time in ticks to be set
*/
void lp_ticker_set_interrupt(timestamp_t timestamp)
{
uint32_t now_us, delta_us, delta_ticks;
if (!lp_ticker_inited) {
lp_ticker_init();
if (timestamp == 0) {
timestamp = 1;
}
now_us = lp_ticker_read();
delta_us = timestamp > now_us ? timestamp - now_us : (uint32_t)((uint64_t)timestamp + 0xFFFFFFFF - now_us);
delta_ticks = USEC_TO_COUNT(delta_us, LOWFREQ_REF_CLK_HZ);
if (delta_ticks == 0) {
delta_ticks = 1;
}
GPT_SetOutputCompareValue(GPT2, kGPT_OutputCompare_Channel1, delta_ticks);
GPT_StopTimer(GPT2);
GPT_SetOutputCompareValue(GPT2, kGPT_OutputCompare_Channel1, timestamp);
GPT_ClearStatusFlags(GPT2, kGPT_OutputCompare1Flag);
GPT_EnableInterrupts(GPT2, kGPT_OutputCompare1InterruptEnable);
GPT_StartTimer(GPT2);
}

2
targets/targets.json
View File

@ -753,7 +753,7 @@
"macros": ["CPU_MIMXRT1052DVL6A", "FSL_RTOS_MBED"],
"inherits": ["Target"],
"detect_code": ["0227"],
"device_has": ["USTICKER", "ANALOGIN", "I2C", "I2CSLAVE", "ERROR_RED", "INTERRUPTIN", "PORTIN", "PORTINOUT", "PORTOUT", "PWMOUT", "RTC", "SERIAL", "SPI", "SPISLAVE", "STDIO_MESSAGES"],
"device_has": ["USTICKER", "LPTICKER", "ANALOGIN", "I2C", "I2CSLAVE", "ERROR_RED", "INTERRUPTIN", "PORTIN", "PORTINOUT", "PORTOUT", "PWMOUT", "RTC", "SERIAL", "SPI", "SPISLAVE", "STDIO_MESSAGES"],
"release_versions": ["2", "5"],
"device_name": "MIMXRT1052"
},