circuitpython/ports/stm32f4/common-hal/busio/SPI.c
2019-12-05 11:38:20 -05:00

367 lines
12 KiB
C

/*
* This file is part of the MicroPython project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2016 Scott Shawcroft
* Copyright (c) 2019 Lucian Copeland for Adafruit Industries
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include <stdbool.h>
#include "shared-bindings/busio/SPI.h"
#include "py/mperrno.h"
#include "py/runtime.h"
#include "stm32f4xx_hal.h"
#include "shared-bindings/microcontroller/__init__.h"
#include "boards/board.h"
#include "supervisor/shared/translate.h"
#include "common-hal/microcontroller/Pin.h"
#define MAX_SPI 6 //TODO; replace this as part of periph cleanup
#define ALL_CLOCKS 0xFF
//arrays use 0 based numbering: SPI1 is stored at index 0
STATIC bool reserved_spi[MAX_SPI];
STATIC bool never_reset_spi[MAX_SPI];
STATIC void spi_clock_enable(uint8_t mask);
STATIC void spi_clock_disable(uint8_t mask);
STATIC uint32_t get_busclock(SPI_TypeDef * instance) {
//SPI2 and 3 are on PCLK1, if they exist.
#ifdef SPI2
if(instance == SPI2) return HAL_RCC_GetPCLK1Freq();
#endif
#ifdef SPI3
if(instance == SPI3) return HAL_RCC_GetPCLK1Freq();
#endif
return HAL_RCC_GetPCLK2Freq();
}
void spi_reset(void) {
uint16_t never_reset_mask = 0x00;
for(int i=0;i<MAX_SPI;i++) {
if (!never_reset_spi[i]) {
reserved_spi[i] = 0x00;
} else {
never_reset_mask |= 1<<i;
}
}
spi_clock_disable(ALL_CLOCKS & ~(never_reset_mask));
}
void common_hal_busio_spi_construct(busio_spi_obj_t *self,
const mcu_pin_obj_t * sck, const mcu_pin_obj_t * mosi,
const mcu_pin_obj_t * miso) {
//match pins to SPI objects
SPI_TypeDef * SPIx;
uint8_t sck_len = sizeof(mcu_spi_sck_list)/sizeof(*mcu_spi_sck_list);
uint8_t mosi_len = sizeof(mcu_spi_mosi_list)/sizeof(*mcu_spi_mosi_list);
uint8_t miso_len = sizeof(mcu_spi_miso_list)/sizeof(*mcu_spi_miso_list);
bool spi_taken = false;
//sck
for(uint i=0; i<sck_len;i++) {
if (mcu_spi_sck_list[i].pin == sck) {
//mosi
for(uint j=0; j<mosi_len;j++) {
if (mcu_spi_mosi_list[j].pin == mosi) {
//miso
for(uint k=0; k<miso_len;k++) {
if ((mcu_spi_miso_list[k].pin == miso) //everything needs the same index
&& (mcu_spi_sck_list[i].spi_index == mcu_spi_mosi_list[j].spi_index)
&& (mcu_spi_sck_list[i].spi_index == mcu_spi_miso_list[k].spi_index)) {
//keep looking if the SPI is taken, edge case
if(reserved_spi[mcu_spi_sck_list[i].spi_index-1]) {
spi_taken = true;
continue;
}
//store pins if not
self->sck = &mcu_spi_sck_list[i];
self->mosi = &mcu_spi_mosi_list[j];
self->miso = &mcu_spi_miso_list[k];
break;
}
}
}
}
}
}
//handle typedef selection, errors
if(self->sck!=NULL && self->mosi!=NULL && self->miso!=NULL ) {
SPIx = mcu_spi_banks[self->sck->spi_index-1];
} else {
if (spi_taken) {
mp_raise_ValueError(translate("Hardware busy, try alternative pins"));
} else {
mp_raise_ValueError(translate("Invalid SPI pin selection"));
}
}
//Start GPIO for each pin
GPIO_InitTypeDef GPIO_InitStruct = {0};
GPIO_InitStruct.Pin = pin_mask(sck->number);
GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
GPIO_InitStruct.Pull = GPIO_NOPULL;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
GPIO_InitStruct.Alternate = self->sck->altfn_index;
HAL_GPIO_Init(pin_port(sck->port), &GPIO_InitStruct);
GPIO_InitStruct.Pin = pin_mask(mosi->number);
GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
GPIO_InitStruct.Pull = GPIO_NOPULL;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
GPIO_InitStruct.Alternate = self->mosi->altfn_index;
HAL_GPIO_Init(pin_port(mosi->port), &GPIO_InitStruct);
GPIO_InitStruct.Pin = pin_mask(miso->number);
GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
GPIO_InitStruct.Pull = GPIO_NOPULL;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
GPIO_InitStruct.Alternate = self->miso->altfn_index;
HAL_GPIO_Init(pin_port(miso->port), &GPIO_InitStruct);
spi_clock_enable(1<<(self->sck->spi_index - 1));
reserved_spi[self->sck->spi_index - 1] = true;
self->handle.Instance = SPIx;
self->handle.Init.Mode = SPI_MODE_MASTER;
self->handle.Init.Direction = SPI_DIRECTION_2LINES;
self->handle.Init.DataSize = SPI_DATASIZE_8BIT;
self->handle.Init.CLKPolarity = SPI_POLARITY_LOW;
self->handle.Init.CLKPhase = SPI_PHASE_1EDGE;
self->handle.Init.NSS = SPI_NSS_SOFT;
self->handle.Init.BaudRatePrescaler = SPI_BAUDRATEPRESCALER_256;
self->handle.Init.FirstBit = SPI_FIRSTBIT_MSB;
self->handle.Init.TIMode = SPI_TIMODE_DISABLE;
self->handle.Init.CRCCalculation = SPI_CRCCALCULATION_DISABLE;
self->handle.Init.CRCPolynomial = 10;
if (HAL_SPI_Init(&self->handle) != HAL_OK)
{
mp_raise_ValueError(translate("SPI Init Error"));
}
self->baudrate = (get_busclock(SPIx)/16);
self->prescaler = 16;
self->polarity = 0;
self->phase = 0;
self->bits = 8;
claim_pin(sck);
claim_pin(mosi);
claim_pin(miso);
}
void common_hal_busio_spi_never_reset(busio_spi_obj_t *self) {
for(size_t i = 0 ; i < MP_ARRAY_SIZE(mcu_spi_banks); i++) {
if (mcu_spi_banks[i] == self->handle.Instance) {
never_reset_spi[i] = true;
never_reset_pin_number(self->sck->pin->port, self->sck->pin->number);
never_reset_pin_number(self->mosi->pin->port, self->mosi->pin->number);
never_reset_pin_number(self->miso->pin->port, self->miso->pin->number);
break;
}
}
}
bool common_hal_busio_spi_deinited(busio_spi_obj_t *self) {
return self->sck->pin == mp_const_none;
}
void common_hal_busio_spi_deinit(busio_spi_obj_t *self) {
spi_clock_disable(1<<(self->sck->spi_index - 1));
reserved_spi[self->sck->spi_index - 1] = false;
never_reset_spi[self->sck->spi_index - 1] = false;
reset_pin_number(self->sck->pin->port,self->sck->pin->number);
reset_pin_number(self->mosi->pin->port,self->mosi->pin->number);
reset_pin_number(self->miso->pin->port,self->miso->pin->number);
self->sck = mp_const_none;
self->mosi = mp_const_none;
self->miso = mp_const_none;
}
STATIC uint32_t stm32_baud_to_spi_div(uint32_t baudrate, uint16_t * prescaler, uint32_t busclock) {
static const uint32_t baud_map[8][2] = {
{2,SPI_BAUDRATEPRESCALER_2},
{4,SPI_BAUDRATEPRESCALER_4},
{8,SPI_BAUDRATEPRESCALER_8},
{16,SPI_BAUDRATEPRESCALER_16},
{32,SPI_BAUDRATEPRESCALER_32},
{64,SPI_BAUDRATEPRESCALER_64},
{128,SPI_BAUDRATEPRESCALER_128},
{256,SPI_BAUDRATEPRESCALER_256}
};
size_t i = 0;
uint16_t divisor;
do {
divisor = baud_map[i][0];
if (baudrate >= (busclock/divisor)) {
*prescaler = divisor;
return baud_map[i][1];
}
i++;
} while (divisor != 256);
//only gets here if requested baud is lower than minimum
*prescaler = 256;
return SPI_BAUDRATEPRESCALER_256;
}
bool common_hal_busio_spi_configure(busio_spi_obj_t *self,
uint32_t baudrate, uint8_t polarity, uint8_t phase, uint8_t bits) {
//This resets the SPI, so check before updating it redundantly
if (baudrate == self->baudrate && polarity== self->polarity
&& phase == self->phase && bits == self->bits) return true;
//Deinit SPI
HAL_SPI_DeInit(&self->handle);
self->handle.Init.DataSize = (bits == 16) ? SPI_DATASIZE_16BIT : SPI_DATASIZE_8BIT;
self->handle.Init.CLKPolarity = (polarity) ? SPI_POLARITY_HIGH : SPI_POLARITY_LOW;
self->handle.Init.CLKPhase = (phase) ? SPI_PHASE_2EDGE : SPI_PHASE_1EDGE;
self->handle.Init.BaudRatePrescaler = stm32_baud_to_spi_div(baudrate, &self->prescaler,
get_busclock(self->handle.Instance));
self->handle.Init.Mode = SPI_MODE_MASTER;
self->handle.Init.Direction = SPI_DIRECTION_2LINES;
self->handle.Init.NSS = SPI_NSS_SOFT;
self->handle.Init.FirstBit = SPI_FIRSTBIT_MSB;
self->handle.Init.TIMode = SPI_TIMODE_DISABLE;
self->handle.Init.CRCCalculation = SPI_CRCCALCULATION_DISABLE;
self->handle.Init.CRCPolynomial = 10;
if (HAL_SPI_Init(&self->handle) != HAL_OK)
{
mp_raise_ValueError(translate("SPI Re-initialization error"));
}
self->baudrate = baudrate;
self->polarity = polarity;
self->phase = phase;
self->bits = bits;
return true;
}
bool common_hal_busio_spi_try_lock(busio_spi_obj_t *self) {
bool grabbed_lock = false;
//Critical section code that may be required at some point.
// uint32_t store_primask = __get_PRIMASK();
// __disable_irq();
// __DMB();
if (!self->has_lock) {
grabbed_lock = true;
self->has_lock = true;
}
// __DMB();
// __set_PRIMASK(store_primask);
return grabbed_lock;
}
bool common_hal_busio_spi_has_lock(busio_spi_obj_t *self) {
return self->has_lock;
}
void common_hal_busio_spi_unlock(busio_spi_obj_t *self) {
self->has_lock = false;
}
bool common_hal_busio_spi_write(busio_spi_obj_t *self,
const uint8_t *data, size_t len) {
HAL_StatusTypeDef result = HAL_SPI_Transmit (&self->handle, (uint8_t *)data, (uint16_t)len, HAL_MAX_DELAY);
return result == HAL_OK;
}
bool common_hal_busio_spi_read(busio_spi_obj_t *self,
uint8_t *data, size_t len, uint8_t write_value) {
HAL_StatusTypeDef result = HAL_SPI_Receive (&self->handle, data, (uint16_t)len, HAL_MAX_DELAY);
return result == HAL_OK;
}
bool common_hal_busio_spi_transfer(busio_spi_obj_t *self,
uint8_t *data_out, uint8_t *data_in, size_t len) {
HAL_StatusTypeDef result = HAL_SPI_TransmitReceive (&self->handle,
data_out, data_in, (uint16_t)len,HAL_MAX_DELAY);
return result == HAL_OK;
}
uint32_t common_hal_busio_spi_get_frequency(busio_spi_obj_t* self) {
//returns actual frequency
uint32_t result = HAL_RCC_GetPCLK2Freq()/self->prescaler;
return result;
}
uint8_t common_hal_busio_spi_get_phase(busio_spi_obj_t* self) {
return self->phase;
}
uint8_t common_hal_busio_spi_get_polarity(busio_spi_obj_t* self) {
return self->polarity;
}
STATIC void spi_clock_enable(uint8_t mask) {
#ifdef SPI1
if (mask & 1<<0) __HAL_RCC_SPI1_CLK_ENABLE();
#endif
#ifdef SPI2
if (mask & 1<<1) __HAL_RCC_SPI2_CLK_ENABLE();
#endif
#ifdef SPI3
if (mask & 1<<2) __HAL_RCC_SPI3_CLK_ENABLE();
#endif
#ifdef SPI4
if (mask & 1<<3) __HAL_RCC_SPI4_CLK_ENABLE();
#endif
#ifdef SPI5
if (mask & 1<<4) __HAL_RCC_SPI5_CLK_ENABLE();
#endif
#ifdef SPI6
if (mask & 1<<5) __HAL_RCC_SPI6_CLK_ENABLE();
#endif
}
STATIC void spi_clock_disable(uint8_t mask) {
#ifdef SPI1
if (mask & 1<<0) __HAL_RCC_SPI1_CLK_DISABLE();
#endif
#ifdef SPI2
if (mask & 1<<1) __HAL_RCC_SPI2_CLK_DISABLE();
#endif
#ifdef SPI3
if (mask & 1<<2) __HAL_RCC_SPI3_CLK_DISABLE();
#endif
#ifdef SPI4
if (mask & 1<<3) __HAL_RCC_SPI4_CLK_DISABLE();
#endif
#ifdef SPI5
if (mask & 1<<4) __HAL_RCC_SPI5_CLK_DISABLE();
#endif
#ifdef SPI6
if (mask & 1<<5) __HAL_RCC_SPI6_CLK_DISABLE();
#endif
}