/*
* adc_stm32f103.c - ADC driver for STM32F103
* In this ADC driver, there are NeuG specific parts.
* You need to modify to use this as generic ADC driver.
*
* Copyright (C) 2011, 2012, 2013, 2015, 2016
* Free Software Initiative of Japan
* Author: NIIBE Yutaka <gniibe@fsij.org>
*
* This file is a part of NeuG, a True Random Number Generator
* implementation based on quantization error of ADC (for STM32F103).
*
* NeuG 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.
*
* NeuG 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 <stdint.h>
#include <stdlib.h>
#include <chopstx.h>
#include <mcu/stm32f103.h>
#include "adc.h"
#define STM32_ADC_ADC1_DMA_PRIORITY 2
#define ADC_SMPR1_SMP_VREF(n) ((n) << 21)
#define ADC_SMPR1_SMP_SENSOR(n) ((n) << 18)
#define ADC_SMPR1_SMP_AN10(n) ((n) << 0)
#define ADC_SMPR1_SMP_AN11(n) ((n) << 3)
#define ADC_SMPR2_SMP_AN0(n) ((n) << 0)
#define ADC_SMPR2_SMP_AN1(n) ((n) << 3)
#define ADC_SMPR2_SMP_AN2(n) ((n) << 6)
#define ADC_SMPR2_SMP_AN9(n) ((n) << 27)
#define ADC_SQR1_NUM_CH(n) (((n) - 1) << 20)
#define ADC_SQR3_SQ1_N(n) ((n) << 0)
#define ADC_SQR3_SQ2_N(n) ((n) << 5)
#define ADC_SQR3_SQ3_N(n) ((n) << 10)
#define ADC_SQR3_SQ4_N(n) ((n) << 15)
#define ADC_SAMPLE_1P5 0
#define ADC_CHANNEL_IN0 0
#define ADC_CHANNEL_IN1 1
#define ADC_CHANNEL_IN2 2
#define ADC_CHANNEL_IN9 9
#define ADC_CHANNEL_IN10 10
#define ADC_CHANNEL_IN11 11
#define ADC_CHANNEL_SENSOR 16
#define ADC_CHANNEL_VREFINT 17
#define DELIBARATELY_DO_IT_WRONG_VREF_SAMPLE_TIME
#define DELIBARATELY_DO_IT_WRONG_START_STOP
#ifdef DELIBARATELY_DO_IT_WRONG_VREF_SAMPLE_TIME
#define ADC_SAMPLE_VREF ADC_SAMPLE_1P5
#define ADC_SAMPLE_SENSOR ADC_SAMPLE_1P5
#else
#define ADC_SAMPLE_VREF ADC_SAMPLE_239P5
#define ADC_SAMPLE_SENSOR ADC_SAMPLE_239P5
#endif
#define NEUG_DMA_CHANNEL STM32_DMA1_STREAM1
#define NEUG_DMA_MODE \
( STM32_DMA_CR_PL (STM32_ADC_ADC1_DMA_PRIORITY) \
| STM32_DMA_CR_MSIZE_WORD | STM32_DMA_CR_PSIZE_WORD \
| STM32_DMA_CR_MINC | STM32_DMA_CR_TCIE \
| STM32_DMA_CR_TEIE )
#define NEUG_ADC_SETTING1_SMPR1 ADC_SMPR1_SMP_VREF(ADC_SAMPLE_VREF) \
| ADC_SMPR1_SMP_SENSOR(ADC_SAMPLE_SENSOR)
#define NEUG_ADC_SETTING1_SMPR2 0
#define NEUG_ADC_SETTING1_SQR3 ADC_SQR3_SQ1_N(ADC_CHANNEL_VREFINT) \
| ADC_SQR3_SQ2_N(ADC_CHANNEL_SENSOR) \
| ADC_SQR3_SQ3_N(ADC_CHANNEL_SENSOR) \
| ADC_SQR3_SQ4_N(ADC_CHANNEL_VREFINT)
#define NEUG_ADC_SETTING1_NUM_CHANNELS 4
/*
* ADC finish interrupt
*/
#define INTR_REQ_DMA1_Channel1 11
static chopstx_intr_t adc_intr;
/*
* Do calibration for both of ADCs.
*/
int
adc_init (void)
{
RCC->APB2ENR |= (RCC_APB2ENR_ADC1EN | RCC_APB2ENR_ADC2EN);
RCC->APB2RSTR = (RCC_APB2RSTR_ADC1RST | RCC_APB2RSTR_ADC2RST);
RCC->APB2RSTR = 0;
ADC1->CR1 = 0;
ADC1->CR2 = ADC_CR2_ADON;
ADC1->CR2 = ADC_CR2_ADON | ADC_CR2_RSTCAL;
while ((ADC1->CR2 & ADC_CR2_RSTCAL) != 0)
;
ADC1->CR2 = ADC_CR2_ADON | ADC_CR2_CAL;
while ((ADC1->CR2 & ADC_CR2_CAL) != 0)
;
ADC1->CR2 = 0;
ADC2->CR1 = 0;
ADC2->CR2 = ADC_CR2_ADON;
ADC2->CR2 = ADC_CR2_ADON | ADC_CR2_RSTCAL;
while ((ADC2->CR2 & ADC_CR2_RSTCAL) != 0)
;
ADC2->CR2 = ADC_CR2_ADON | ADC_CR2_CAL;
while ((ADC2->CR2 & ADC_CR2_CAL) != 0)
;
ADC2->CR2 = 0;
RCC->APB2ENR &= ~(RCC_APB2ENR_ADC1EN | RCC_APB2ENR_ADC2EN);
chopstx_claim_irq (&adc_intr, INTR_REQ_DMA1_Channel1);
return 0;
}
#include "board.h"
#include "sys.h"
static void
get_adc_config (uint32_t config[4])
{
config[2] = ADC_SQR1_NUM_CH(2);
switch (SYS_BOARD_ID)
{
case BOARD_ID_FST_01:
config[0] = 0;
config[1] = ADC_SMPR2_SMP_AN0(ADC_SAMPLE_1P5)
| ADC_SMPR2_SMP_AN9(ADC_SAMPLE_1P5);
config[3] = ADC_SQR3_SQ1_N(ADC_CHANNEL_IN0)
| ADC_SQR3_SQ2_N(ADC_CHANNEL_IN9);
break;
case BOARD_ID_OLIMEX_STM32_H103:
case BOARD_ID_STBEE:
config[0] = ADC_SMPR1_SMP_AN10(ADC_SAMPLE_1P5)
| ADC_SMPR1_SMP_AN11(ADC_SAMPLE_1P5);
config[1] = 0;
config[3] = ADC_SQR3_SQ1_N(ADC_CHANNEL_IN10)
| ADC_SQR3_SQ2_N(ADC_CHANNEL_IN11);
break;
case BOARD_ID_STBEE_MINI:
config[0] = 0;
config[1] = ADC_SMPR2_SMP_AN1(ADC_SAMPLE_1P5)
| ADC_SMPR2_SMP_AN2(ADC_SAMPLE_1P5);
config[3] = ADC_SQR3_SQ1_N(ADC_CHANNEL_IN1)
| ADC_SQR3_SQ2_N(ADC_CHANNEL_IN2);
break;
case BOARD_ID_CQ_STARM:
case BOARD_ID_FST_01_00:
case BOARD_ID_MAPLE_MINI:
case BOARD_ID_STM32_PRIMER2:
case BOARD_ID_STM8S_DISCOVERY:
case BOARD_ID_ST_DONGLE:
case BOARD_ID_ST_NUCLEO_F103:
case BOARD_ID_NITROKEY_START:
default:
config[0] = 0;
config[1] = ADC_SMPR2_SMP_AN0(ADC_SAMPLE_1P5)
| ADC_SMPR2_SMP_AN1(ADC_SAMPLE_1P5);
config[3] = ADC_SQR3_SQ1_N(ADC_CHANNEL_IN0)
| ADC_SQR3_SQ2_N(ADC_CHANNEL_IN1);
break;
}
}
void
adc_start (void)
{
uint32_t config[4];
get_adc_config (config);
/* Use DMA channel 1. */
RCC->AHBENR |= RCC_AHBENR_DMA1EN;
DMA1_Channel1->CCR = STM32_DMA_CCR_RESET_VALUE;
DMA1->IFCR = 0xffffffff;
RCC->APB2ENR |= (RCC_APB2ENR_ADC1EN | RCC_APB2ENR_ADC2EN);
ADC1->CR1 = (ADC_CR1_DUALMOD_2 | ADC_CR1_DUALMOD_1 | ADC_CR1_DUALMOD_0
| ADC_CR1_SCAN);
ADC1->CR2 = (ADC_CR2_TSVREFE | ADC_CR2_EXTTRIG | ADC_CR2_SWSTART
| ADC_CR2_EXTSEL | ADC_CR2_DMA | ADC_CR2_CONT | ADC_CR2_ADON);
ADC1->SMPR1 = NEUG_ADC_SETTING1_SMPR1;
ADC1->SMPR2 = NEUG_ADC_SETTING1_SMPR2;
ADC1->SQR1 = ADC_SQR1_NUM_CH(NEUG_ADC_SETTING1_NUM_CHANNELS);
ADC1->SQR2 = 0;
ADC1->SQR3 = NEUG_ADC_SETTING1_SQR3;
ADC2->CR1 = (ADC_CR1_DUALMOD_2 | ADC_CR1_DUALMOD_1 | ADC_CR1_DUALMOD_0
| ADC_CR1_SCAN);
ADC2->CR2 = ADC_CR2_EXTTRIG | ADC_CR2_CONT | ADC_CR2_ADON;
ADC2->SMPR1 = config[0];
ADC2->SMPR2 = config[1];
ADC2->SQR1 = config[2];
ADC2->SQR2 = 0;
ADC2->SQR3 = config[3];
#ifdef DELIBARATELY_DO_IT_WRONG_START_STOP
/*
* We could just let ADC run continuously always and only enable DMA
* to receive stable data from ADC. But our purpose is not to get
* correct data but noise. In fact, we can get more noise when we
* start/stop ADC each time.
*/
ADC2->CR2 = 0;
ADC1->CR2 = 0;
#else
/* Start conversion. */
ADC2->CR2 = ADC_CR2_EXTTRIG | ADC_CR2_CONT | ADC_CR2_ADON;
ADC1->CR2 = (ADC_CR2_TSVREFE | ADC_CR2_EXTTRIG | ADC_CR2_SWSTART
| ADC_CR2_EXTSEL | ADC_CR2_DMA | ADC_CR2_CONT | ADC_CR2_ADON);
#endif
}
uint32_t adc_buf[64];
void
adc_start_conversion (int offset, int count)
{
DMA1_Channel1->CPAR = (uint32_t)&ADC1->DR; /* SetPeripheral */
DMA1_Channel1->CMAR = (uint32_t)&adc_buf[offset]; /* SetMemory0 */
DMA1_Channel1->CNDTR = count; /* Counter */
DMA1_Channel1->CCR = NEUG_DMA_MODE | DMA_CCR1_EN; /* Mode */
#ifdef DELIBARATELY_DO_IT_WRONG_START_STOP
/* Power on */
ADC2->CR2 = ADC_CR2_EXTTRIG | ADC_CR2_CONT | ADC_CR2_ADON;
ADC1->CR2 = (ADC_CR2_TSVREFE | ADC_CR2_EXTTRIG | ADC_CR2_SWSTART
| ADC_CR2_EXTSEL | ADC_CR2_DMA | ADC_CR2_CONT | ADC_CR2_ADON);
/*
* Start conversion. tSTAB is 1uS, but we don't follow the spec, to
* get more noise.
*/
ADC2->CR2 = ADC_CR2_EXTTRIG | ADC_CR2_CONT | ADC_CR2_ADON;
ADC1->CR2 = (ADC_CR2_TSVREFE | ADC_CR2_EXTTRIG | ADC_CR2_SWSTART
| ADC_CR2_EXTSEL | ADC_CR2_DMA | ADC_CR2_CONT | ADC_CR2_ADON);
#endif
}
static void adc_stop_conversion (void)
{
DMA1_Channel1->CCR &= ~DMA_CCR1_EN;
#ifdef DELIBARATELY_DO_IT_WRONG_START_STOP
ADC2->CR2 = 0;
ADC1->CR2 = 0;
#endif
}
void
adc_stop (void)
{
ADC1->CR1 = 0;
ADC1->CR2 = 0;
ADC2->CR1 = 0;
ADC2->CR2 = 0;
RCC->AHBENR &= ~RCC_AHBENR_DMA1EN;
RCC->APB2ENR &= ~(RCC_APB2ENR_ADC1EN | RCC_APB2ENR_ADC2EN);
}
static uint32_t adc_err;
/*
* Return 0 on success.
* Return 1 on error.
*/
int
adc_wait_completion (void)
{
uint32_t flags;
while (1)
{
chopstx_poll (NULL, 1, &adc_intr);
flags = DMA1->ISR & STM32_DMA_ISR_MASK; /* Channel 1 interrupt cause. */
/*
* Clear interrupt cause of channel 1.
*
* Note that CGIFx=0, as CGIFx=1 clears all of GIF, HTIF, TCIF
* and TEIF.
*/
DMA1->IFCR = (flags & ~1);
if ((flags & STM32_DMA_ISR_TEIF) != 0) /* DMA errors */
{
/* Should never happened. If any, it's coding error. */
/* Access an unmapped address space or alignment violation. */
adc_err++;
adc_stop_conversion ();
return 1;
}
else if ((flags & STM32_DMA_ISR_TCIF) != 0) /* Transfer complete */
{
adc_stop_conversion ();
return 0;
}
}
}