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circuitpython/ports/stm32/uart.c
Damien George 73e8b7e0e4 stm32: Update components to work with new H7xx HAL.
2019-07-03 23:40:49 +10:00

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/*
* This file is part of the MicroPython project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2013, 2014 Damien P. George
*
* 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 <stdio.h>
#include <string.h>
#include <stdarg.h>
#include "py/runtime.h"
#include "py/stream.h"
#include "py/mperrno.h"
#include "py/mphal.h"
#include "lib/utils/interrupt_char.h"
#include "lib/utils/mpirq.h"
#include "uart.h"
#include "irq.h"
#include "pendsv.h"
#if defined(STM32F4)
#define UART_RXNE_IS_SET(uart) ((uart)->SR & USART_SR_RXNE)
#elif defined(STM32H7)
#define UART_RXNE_IS_SET(uart) ((uart)->ISR & USART_ISR_RXNE_RXFNE)
#else
#define UART_RXNE_IS_SET(uart) ((uart)->ISR & USART_ISR_RXNE)
#endif
#define UART_RXNE_IT_EN(uart) do { (uart)->CR1 |= USART_CR1_RXNEIE; } while (0)
#define UART_RXNE_IT_DIS(uart) do { (uart)->CR1 &= ~USART_CR1_RXNEIE; } while (0)
#define USART_CR1_IE_BASE (USART_CR1_PEIE | USART_CR1_TXEIE | USART_CR1_TCIE | USART_CR1_RXNEIE | USART_CR1_IDLEIE)
#define USART_CR2_IE_BASE (USART_CR2_LBDIE)
#define USART_CR3_IE_BASE (USART_CR3_CTSIE | USART_CR3_EIE)
#if defined(STM32F0)
#define USART_CR1_IE_ALL (USART_CR1_IE_BASE | USART_CR1_EOBIE | USART_CR1_RTOIE | USART_CR1_CMIE)
#define USART_CR2_IE_ALL (USART_CR2_IE_BASE)
#define USART_CR3_IE_ALL (USART_CR3_IE_BASE | USART_CR3_WUFIE)
#elif defined(STM32F4)
#define USART_CR1_IE_ALL (USART_CR1_IE_BASE)
#define USART_CR2_IE_ALL (USART_CR2_IE_BASE)
#define USART_CR3_IE_ALL (USART_CR3_IE_BASE)
#elif defined(STM32F7)
#define USART_CR1_IE_ALL (USART_CR1_IE_BASE | USART_CR1_EOBIE | USART_CR1_RTOIE | USART_CR1_CMIE)
#define USART_CR2_IE_ALL (USART_CR2_IE_BASE)
#if defined(USART_CR3_TCBGTIE)
#define USART_CR3_IE_ALL (USART_CR3_IE_BASE | USART_CR3_TCBGTIE)
#else
#define USART_CR3_IE_ALL (USART_CR3_IE_BASE)
#endif
#elif defined(STM32H7)
#define USART_CR1_IE_ALL (USART_CR1_IE_BASE | USART_CR1_RXFFIE | USART_CR1_TXFEIE | USART_CR1_EOBIE | USART_CR1_RTOIE | USART_CR1_CMIE)
#define USART_CR2_IE_ALL (USART_CR2_IE_BASE)
#define USART_CR3_IE_ALL (USART_CR3_IE_BASE | USART_CR3_RXFTIE | USART_CR3_TCBGTIE | USART_CR3_TXFTIE | USART_CR3_WUFIE)
#elif defined(STM32L4)
#define USART_CR1_IE_ALL (USART_CR1_IE_BASE | USART_CR1_EOBIE | USART_CR1_RTOIE | USART_CR1_CMIE)
#define USART_CR2_IE_ALL (USART_CR2_IE_BASE)
#if defined(USART_CR3_TCBGTIE)
#define USART_CR3_IE_ALL (USART_CR3_IE_BASE | USART_CR3_TCBGTIE | USART_CR3_WUFIE)
#else
#define USART_CR3_IE_ALL (USART_CR3_IE_BASE | USART_CR3_WUFIE)
#endif
#endif
extern void NORETURN __fatal_error(const char *msg);
void uart_init0(void) {
#if defined(STM32H7)
RCC_PeriphCLKInitTypeDef RCC_PeriphClkInit = {0};
// Configure USART1/6 clock source
RCC_PeriphClkInit.PeriphClockSelection = RCC_PERIPHCLK_USART16;
RCC_PeriphClkInit.Usart16ClockSelection = RCC_USART16CLKSOURCE_D2PCLK2;
if (HAL_RCCEx_PeriphCLKConfig(&RCC_PeriphClkInit) != HAL_OK) {
__fatal_error("HAL_RCCEx_PeriphCLKConfig");
}
// Configure USART2/3/4/5/7/8 clock source
RCC_PeriphClkInit.PeriphClockSelection = RCC_PERIPHCLK_USART234578;
RCC_PeriphClkInit.Usart16ClockSelection = RCC_USART234578CLKSOURCE_D2PCLK1;
if (HAL_RCCEx_PeriphCLKConfig(&RCC_PeriphClkInit) != HAL_OK) {
__fatal_error("HAL_RCCEx_PeriphCLKConfig");
}
#endif
}
// unregister all interrupt sources
void uart_deinit_all(void) {
for (int i = 0; i < MP_ARRAY_SIZE(MP_STATE_PORT(pyb_uart_obj_all)); i++) {
pyb_uart_obj_t *uart_obj = MP_STATE_PORT(pyb_uart_obj_all)[i];
if (uart_obj != NULL && !uart_obj->is_static) {
uart_deinit(uart_obj);
MP_STATE_PORT(pyb_uart_obj_all)[i] = NULL;
}
}
}
bool uart_exists(int uart_id) {
if (uart_id > MP_ARRAY_SIZE(MP_STATE_PORT(pyb_uart_obj_all))) {
// safeguard against pyb_uart_obj_all array being configured too small
return false;
}
switch (uart_id) {
#if defined(MICROPY_HW_UART1_TX) && defined(MICROPY_HW_UART1_RX)
case PYB_UART_1: return true;
#endif
#if defined(MICROPY_HW_UART2_TX) && defined(MICROPY_HW_UART2_RX)
case PYB_UART_2: return true;
#endif
#if defined(MICROPY_HW_UART3_TX) && defined(MICROPY_HW_UART3_RX)
case PYB_UART_3: return true;
#endif
#if defined(MICROPY_HW_UART4_TX) && defined(MICROPY_HW_UART4_RX)
case PYB_UART_4: return true;
#endif
#if defined(MICROPY_HW_UART5_TX) && defined(MICROPY_HW_UART5_RX)
case PYB_UART_5: return true;
#endif
#if defined(MICROPY_HW_UART6_TX) && defined(MICROPY_HW_UART6_RX)
case PYB_UART_6: return true;
#endif
#if defined(MICROPY_HW_UART7_TX) && defined(MICROPY_HW_UART7_RX)
case PYB_UART_7: return true;
#endif
#if defined(MICROPY_HW_UART8_TX) && defined(MICROPY_HW_UART8_RX)
case PYB_UART_8: return true;
#endif
#if defined(MICROPY_HW_UART9_TX) && defined(MICROPY_HW_UART9_RX)
case PYB_UART_9: return true;
#endif
#if defined(MICROPY_HW_UART10_TX) && defined(MICROPY_HW_UART10_RX)
case PYB_UART_10: return true;
#endif
default: return false;
}
}
// assumes Init parameters have been set up correctly
bool uart_init(pyb_uart_obj_t *uart_obj,
uint32_t baudrate, uint32_t bits, uint32_t parity, uint32_t stop, uint32_t flow) {
USART_TypeDef *UARTx;
IRQn_Type irqn;
int uart_unit;
const pin_obj_t *pins[4] = {0};
switch (uart_obj->uart_id) {
#if defined(MICROPY_HW_UART1_TX) && defined(MICROPY_HW_UART1_RX)
case PYB_UART_1:
uart_unit = 1;
UARTx = USART1;
irqn = USART1_IRQn;
pins[0] = MICROPY_HW_UART1_TX;
pins[1] = MICROPY_HW_UART1_RX;
__HAL_RCC_USART1_CLK_ENABLE();
break;
#endif
#if defined(MICROPY_HW_UART2_TX) && defined(MICROPY_HW_UART2_RX)
case PYB_UART_2:
uart_unit = 2;
UARTx = USART2;
irqn = USART2_IRQn;
pins[0] = MICROPY_HW_UART2_TX;
pins[1] = MICROPY_HW_UART2_RX;
#if defined(MICROPY_HW_UART2_RTS)
if (flow & UART_HWCONTROL_RTS) {
pins[2] = MICROPY_HW_UART2_RTS;
}
#endif
#if defined(MICROPY_HW_UART2_CTS)
if (flow & UART_HWCONTROL_CTS) {
pins[3] = MICROPY_HW_UART2_CTS;
}
#endif
__HAL_RCC_USART2_CLK_ENABLE();
break;
#endif
#if defined(MICROPY_HW_UART3_TX) && defined(MICROPY_HW_UART3_RX)
case PYB_UART_3:
uart_unit = 3;
UARTx = USART3;
#if defined(STM32F0)
irqn = USART3_8_IRQn;
#else
irqn = USART3_IRQn;
#endif
pins[0] = MICROPY_HW_UART3_TX;
pins[1] = MICROPY_HW_UART3_RX;
#if defined(MICROPY_HW_UART3_RTS)
if (flow & UART_HWCONTROL_RTS) {
pins[2] = MICROPY_HW_UART3_RTS;
}
#endif
#if defined(MICROPY_HW_UART3_CTS)
if (flow & UART_HWCONTROL_CTS) {
pins[3] = MICROPY_HW_UART3_CTS;
}
#endif
__HAL_RCC_USART3_CLK_ENABLE();
break;
#endif
#if defined(MICROPY_HW_UART4_TX) && defined(MICROPY_HW_UART4_RX)
case PYB_UART_4:
uart_unit = 4;
#if defined(STM32F0)
UARTx = USART4;
irqn = USART3_8_IRQn;
__HAL_RCC_USART4_CLK_ENABLE();
#else
UARTx = UART4;
irqn = UART4_IRQn;
__HAL_RCC_UART4_CLK_ENABLE();
#endif
pins[0] = MICROPY_HW_UART4_TX;
pins[1] = MICROPY_HW_UART4_RX;
break;
#endif
#if defined(MICROPY_HW_UART5_TX) && defined(MICROPY_HW_UART5_RX)
case PYB_UART_5:
uart_unit = 5;
#if defined(STM32F0)
UARTx = USART5;
irqn = USART3_8_IRQn;
__HAL_RCC_USART5_CLK_ENABLE();
#else
UARTx = UART5;
irqn = UART5_IRQn;
__HAL_RCC_UART5_CLK_ENABLE();
#endif
pins[0] = MICROPY_HW_UART5_TX;
pins[1] = MICROPY_HW_UART5_RX;
break;
#endif
#if defined(MICROPY_HW_UART6_TX) && defined(MICROPY_HW_UART6_RX)
case PYB_UART_6:
uart_unit = 6;
UARTx = USART6;
#if defined(STM32F0)
irqn = USART3_8_IRQn;
#else
irqn = USART6_IRQn;
#endif
pins[0] = MICROPY_HW_UART6_TX;
pins[1] = MICROPY_HW_UART6_RX;
#if defined(MICROPY_HW_UART6_RTS)
if (flow & UART_HWCONTROL_RTS) {
pins[2] = MICROPY_HW_UART6_RTS;
}
#endif
#if defined(MICROPY_HW_UART6_CTS)
if (flow & UART_HWCONTROL_CTS) {
pins[3] = MICROPY_HW_UART6_CTS;
}
#endif
__HAL_RCC_USART6_CLK_ENABLE();
break;
#endif
#if defined(MICROPY_HW_UART7_TX) && defined(MICROPY_HW_UART7_RX)
case PYB_UART_7:
uart_unit = 7;
#if defined(STM32F0)
UARTx = USART7;
irqn = USART3_8_IRQn;
__HAL_RCC_USART7_CLK_ENABLE();
#else
UARTx = UART7;
irqn = UART7_IRQn;
__HAL_RCC_UART7_CLK_ENABLE();
#endif
pins[0] = MICROPY_HW_UART7_TX;
pins[1] = MICROPY_HW_UART7_RX;
break;
#endif
#if defined(MICROPY_HW_UART8_TX) && defined(MICROPY_HW_UART8_RX)
case PYB_UART_8:
uart_unit = 8;
#if defined(STM32F0)
UARTx = USART8;
irqn = USART3_8_IRQn;
__HAL_RCC_USART8_CLK_ENABLE();
#else
UARTx = UART8;
irqn = UART8_IRQn;
__HAL_RCC_UART8_CLK_ENABLE();
#endif
pins[0] = MICROPY_HW_UART8_TX;
pins[1] = MICROPY_HW_UART8_RX;
break;
#endif
#if defined(MICROPY_HW_UART9_TX) && defined(MICROPY_HW_UART9_RX)
case PYB_UART_9:
uart_unit = 9;
UARTx = UART9;
irqn = UART9_IRQn;
__HAL_RCC_UART9_CLK_ENABLE();
pins[0] = MICROPY_HW_UART9_TX;
pins[1] = MICROPY_HW_UART9_RX;
break;
#endif
#if defined(MICROPY_HW_UART10_TX) && defined(MICROPY_HW_UART10_RX)
case PYB_UART_10:
uart_unit = 10;
UARTx = UART10;
irqn = UART10_IRQn;
__HAL_RCC_UART10_CLK_ENABLE();
pins[0] = MICROPY_HW_UART10_TX;
pins[1] = MICROPY_HW_UART10_RX;
break;
#endif
default:
// UART does not exist or is not configured for this board
return false;
}
uint32_t mode = MP_HAL_PIN_MODE_ALT;
uint32_t pull = MP_HAL_PIN_PULL_UP;
for (uint i = 0; i < 4; i++) {
if (pins[i] != NULL) {
bool ret = mp_hal_pin_config_alt(pins[i], mode, pull, AF_FN_UART, uart_unit);
if (!ret) {
return false;
}
}
}
uart_obj->uartx = UARTx;
// init UARTx
UART_HandleTypeDef huart;
memset(&huart, 0, sizeof(huart));
huart.Instance = UARTx;
huart.Init.BaudRate = baudrate;
huart.Init.WordLength = bits;
huart.Init.StopBits = stop;
huart.Init.Parity = parity;
huart.Init.Mode = UART_MODE_TX_RX;
huart.Init.HwFlowCtl = flow;
huart.Init.OverSampling = UART_OVERSAMPLING_16;
HAL_UART_Init(&huart);
// Disable all individual UART IRQs, but enable the global handler
uart_obj->uartx->CR1 &= ~USART_CR1_IE_ALL;
uart_obj->uartx->CR2 &= ~USART_CR2_IE_ALL;
uart_obj->uartx->CR3 &= ~USART_CR3_IE_ALL;
NVIC_SetPriority(IRQn_NONNEG(irqn), IRQ_PRI_UART);
HAL_NVIC_EnableIRQ(irqn);
uart_obj->is_enabled = true;
uart_obj->attached_to_repl = false;
if (bits == UART_WORDLENGTH_9B && parity == UART_PARITY_NONE) {
uart_obj->char_mask = 0x1ff;
uart_obj->char_width = CHAR_WIDTH_9BIT;
} else {
if (bits == UART_WORDLENGTH_9B || parity == UART_PARITY_NONE) {
uart_obj->char_mask = 0xff;
} else {
uart_obj->char_mask = 0x7f;
}
uart_obj->char_width = CHAR_WIDTH_8BIT;
}
uart_obj->mp_irq_trigger = 0;
uart_obj->mp_irq_obj = NULL;
return true;
}
void uart_set_rxbuf(pyb_uart_obj_t *self, size_t len, void *buf) {
self->read_buf_head = 0;
self->read_buf_tail = 0;
self->read_buf_len = len;
self->read_buf = buf;
if (len == 0) {
UART_RXNE_IT_DIS(self->uartx);
} else {
UART_RXNE_IT_EN(self->uartx);
}
}
void uart_deinit(pyb_uart_obj_t *self) {
self->is_enabled = false;
// Disable UART
self->uartx->CR1 &= ~USART_CR1_UE;
// Reset and turn off the UART peripheral
if (self->uart_id == 1) {
HAL_NVIC_DisableIRQ(USART1_IRQn);
__HAL_RCC_USART1_FORCE_RESET();
__HAL_RCC_USART1_RELEASE_RESET();
__HAL_RCC_USART1_CLK_DISABLE();
} else if (self->uart_id == 2) {
HAL_NVIC_DisableIRQ(USART2_IRQn);
__HAL_RCC_USART2_FORCE_RESET();
__HAL_RCC_USART2_RELEASE_RESET();
__HAL_RCC_USART2_CLK_DISABLE();
#if defined(USART3)
} else if (self->uart_id == 3) {
#if !defined(STM32F0)
HAL_NVIC_DisableIRQ(USART3_IRQn);
#endif
__HAL_RCC_USART3_FORCE_RESET();
__HAL_RCC_USART3_RELEASE_RESET();
__HAL_RCC_USART3_CLK_DISABLE();
#endif
#if defined(UART4)
} else if (self->uart_id == 4) {
HAL_NVIC_DisableIRQ(UART4_IRQn);
__HAL_RCC_UART4_FORCE_RESET();
__HAL_RCC_UART4_RELEASE_RESET();
__HAL_RCC_UART4_CLK_DISABLE();
#endif
#if defined(USART4)
} else if (self->uart_id == 4) {
__HAL_RCC_USART4_FORCE_RESET();
__HAL_RCC_USART4_RELEASE_RESET();
__HAL_RCC_USART4_CLK_DISABLE();
#endif
#if defined(UART5)
} else if (self->uart_id == 5) {
HAL_NVIC_DisableIRQ(UART5_IRQn);
__HAL_RCC_UART5_FORCE_RESET();
__HAL_RCC_UART5_RELEASE_RESET();
__HAL_RCC_UART5_CLK_DISABLE();
#endif
#if defined(USART5)
} else if (self->uart_id == 5) {
__HAL_RCC_USART5_FORCE_RESET();
__HAL_RCC_USART5_RELEASE_RESET();
__HAL_RCC_USART5_CLK_DISABLE();
#endif
#if defined(UART6)
} else if (self->uart_id == 6) {
HAL_NVIC_DisableIRQ(USART6_IRQn);
__HAL_RCC_USART6_FORCE_RESET();
__HAL_RCC_USART6_RELEASE_RESET();
__HAL_RCC_USART6_CLK_DISABLE();
#endif
#if defined(UART7)
} else if (self->uart_id == 7) {
HAL_NVIC_DisableIRQ(UART7_IRQn);
__HAL_RCC_UART7_FORCE_RESET();
__HAL_RCC_UART7_RELEASE_RESET();
__HAL_RCC_UART7_CLK_DISABLE();
#endif
#if defined(USART7)
} else if (self->uart_id == 7) {
__HAL_RCC_USART7_FORCE_RESET();
__HAL_RCC_USART7_RELEASE_RESET();
__HAL_RCC_USART7_CLK_DISABLE();
#endif
#if defined(UART8)
} else if (self->uart_id == 8) {
HAL_NVIC_DisableIRQ(UART8_IRQn);
__HAL_RCC_UART8_FORCE_RESET();
__HAL_RCC_UART8_RELEASE_RESET();
__HAL_RCC_UART8_CLK_DISABLE();
#endif
#if defined(USART8)
} else if (self->uart_id == 8) {
__HAL_RCC_USART8_FORCE_RESET();
__HAL_RCC_USART8_RELEASE_RESET();
__HAL_RCC_USART8_CLK_DISABLE();
#endif
#if defined(UART9)
} else if (self->uart_id == 9) {
HAL_NVIC_DisableIRQ(UART9_IRQn);
__HAL_RCC_UART9_FORCE_RESET();
__HAL_RCC_UART9_RELEASE_RESET();
__HAL_RCC_UART9_CLK_DISABLE();
#endif
#if defined(UART10)
} else if (self->uart_id == 10) {
HAL_NVIC_DisableIRQ(UART10_IRQn);
__HAL_RCC_UART10_FORCE_RESET();
__HAL_RCC_UART10_RELEASE_RESET();
__HAL_RCC_UART10_CLK_DISABLE();
#endif
}
}
void uart_attach_to_repl(pyb_uart_obj_t *self, bool attached) {
self->attached_to_repl = attached;
}
uint32_t uart_get_baudrate(pyb_uart_obj_t *self) {
uint32_t uart_clk = 0;
#if defined(STM32F0)
uart_clk = HAL_RCC_GetPCLK1Freq();
#elif defined(STM32F7)
switch ((RCC->DCKCFGR2 >> ((self->uart_id - 1) * 2)) & 3) {
case 0:
if (self->uart_id == 1 || self->uart_id == 6) {
uart_clk = HAL_RCC_GetPCLK2Freq();
} else {
uart_clk = HAL_RCC_GetPCLK1Freq();
}
break;
case 1:
uart_clk = HAL_RCC_GetSysClockFreq();
break;
case 2:
uart_clk = HSI_VALUE;
break;
case 3:
uart_clk = LSE_VALUE;
break;
}
#elif defined(STM32H7)
uint32_t csel;
if (self->uart_id == 1 || self->uart_id == 6) {
csel = RCC->D2CCIP2R >> 3;
} else {
csel = RCC->D2CCIP2R;
}
switch (csel & 3) {
case 0:
if (self->uart_id == 1 || self->uart_id == 6) {
uart_clk = HAL_RCC_GetPCLK2Freq();
} else {
uart_clk = HAL_RCC_GetPCLK1Freq();
}
break;
case 3:
uart_clk = HSI_VALUE;
break;
case 4:
uart_clk = CSI_VALUE;
break;
case 5:
uart_clk = LSE_VALUE;
break;
default:
break;
}
#else
if (self->uart_id == 1
#if defined(USART6)
|| self->uart_id == 6
#endif
#if defined(UART9)
|| self->uart_id == 9
#endif
#if defined(UART10)
|| self->uart_id == 10
#endif
) {
uart_clk = HAL_RCC_GetPCLK2Freq();
} else {
uart_clk = HAL_RCC_GetPCLK1Freq();
}
#endif
// This formula assumes UART_OVERSAMPLING_16
uint32_t baudrate = uart_clk / self->uartx->BRR;
return baudrate;
}
mp_uint_t uart_rx_any(pyb_uart_obj_t *self) {
int buffer_bytes = self->read_buf_head - self->read_buf_tail;
if (buffer_bytes < 0) {
return buffer_bytes + self->read_buf_len;
} else if (buffer_bytes > 0) {
return buffer_bytes;
} else {
return UART_RXNE_IS_SET(self->uartx) != 0;
}
}
// Waits at most timeout milliseconds for at least 1 char to become ready for
// reading (from buf or for direct reading).
// Returns true if something available, false if not.
bool uart_rx_wait(pyb_uart_obj_t *self, uint32_t timeout) {
uint32_t start = HAL_GetTick();
for (;;) {
if (self->read_buf_tail != self->read_buf_head || UART_RXNE_IS_SET(self->uartx)) {
return true; // have at least 1 char ready for reading
}
if (HAL_GetTick() - start >= timeout) {
return false; // timeout
}
MICROPY_EVENT_POLL_HOOK
}
}
// assumes there is a character available
int uart_rx_char(pyb_uart_obj_t *self) {
if (self->read_buf_tail != self->read_buf_head) {
// buffering via IRQ
int data;
if (self->char_width == CHAR_WIDTH_9BIT) {
data = ((uint16_t*)self->read_buf)[self->read_buf_tail];
} else {
data = self->read_buf[self->read_buf_tail];
}
self->read_buf_tail = (self->read_buf_tail + 1) % self->read_buf_len;
if (UART_RXNE_IS_SET(self->uartx)) {
// UART was stalled by flow ctrl: re-enable IRQ now we have room in buffer
UART_RXNE_IT_EN(self->uartx);
}
return data;
} else {
// no buffering
#if defined(STM32F0) || defined(STM32F7) || defined(STM32L4) || defined(STM32H7)
int data = self->uartx->RDR & self->char_mask;
self->uartx->ICR = USART_ICR_ORECF; // clear ORE if it was set
return data;
#else
return self->uartx->DR & self->char_mask;
#endif
}
}
// Waits at most timeout milliseconds for TX register to become empty.
// Returns true if can write, false if can't.
bool uart_tx_wait(pyb_uart_obj_t *self, uint32_t timeout) {
uint32_t start = HAL_GetTick();
for (;;) {
if (uart_tx_avail(self)) {
return true; // tx register is empty
}
if (HAL_GetTick() - start >= timeout) {
return false; // timeout
}
MICROPY_EVENT_POLL_HOOK
}
}
// Waits at most timeout milliseconds for UART flag to be set.
// Returns true if flag is/was set, false on timeout.
STATIC bool uart_wait_flag_set(pyb_uart_obj_t *self, uint32_t flag, uint32_t timeout) {
// Note: we don't use WFI to idle in this loop because UART tx doesn't generate
// an interrupt and the flag can be set quickly if the baudrate is large.
uint32_t start = HAL_GetTick();
for (;;) {
#if defined(STM32F4)
if (self->uartx->SR & flag) {
return true;
}
#else
if (self->uartx->ISR & flag) {
return true;
}
#endif
if (timeout == 0 || HAL_GetTick() - start >= timeout) {
return false; // timeout
}
}
}
// src - a pointer to the data to send (16-bit aligned for 9-bit chars)
// num_chars - number of characters to send (9-bit chars count for 2 bytes from src)
// *errcode - returns 0 for success, MP_Exxx on error
// returns the number of characters sent (valid even if there was an error)
size_t uart_tx_data(pyb_uart_obj_t *self, const void *src_in, size_t num_chars, int *errcode) {
if (num_chars == 0) {
*errcode = 0;
return 0;
}
uint32_t timeout;
if (self->uartx->CR3 & USART_CR3_CTSE) {
// CTS can hold off transmission for an arbitrarily long time. Apply
// the overall timeout rather than the character timeout.
timeout = self->timeout;
} else {
// The timeout specified here is for waiting for the TX data register to
// become empty (ie between chars), as well as for the final char to be
// completely transferred. The default value for timeout_char is long
// enough for 1 char, but we need to double it to wait for the last char
// to be transferred to the data register, and then to be transmitted.
timeout = 2 * self->timeout_char;
}
const uint8_t *src = (const uint8_t*)src_in;
size_t num_tx = 0;
USART_TypeDef *uart = self->uartx;
while (num_tx < num_chars) {
if (!uart_wait_flag_set(self, UART_FLAG_TXE, timeout)) {
*errcode = MP_ETIMEDOUT;
return num_tx;
}
uint32_t data;
if (self->char_width == CHAR_WIDTH_9BIT) {
data = *((uint16_t*)src) & 0x1ff;
src += 2;
} else {
data = *src++;
}
#if defined(STM32F4)
uart->DR = data;
#else
uart->TDR = data;
#endif
++num_tx;
}
// wait for the UART frame to complete
if (!uart_wait_flag_set(self, UART_FLAG_TC, timeout)) {
*errcode = MP_ETIMEDOUT;
return num_tx;
}
*errcode = 0;
return num_tx;
}
void uart_tx_strn(pyb_uart_obj_t *uart_obj, const char *str, uint len) {
int errcode;
uart_tx_data(uart_obj, str, len, &errcode);
}
// this IRQ handler is set up to handle RXNE interrupts only
void uart_irq_handler(mp_uint_t uart_id) {
// get the uart object
pyb_uart_obj_t *self = MP_STATE_PORT(pyb_uart_obj_all)[uart_id - 1];
if (self == NULL) {
// UART object has not been set, so we can't do anything, not
// even disable the IRQ. This should never happen.
return;
}
if (UART_RXNE_IS_SET(self->uartx)) {
if (self->read_buf_len != 0) {
uint16_t next_head = (self->read_buf_head + 1) % self->read_buf_len;
if (next_head != self->read_buf_tail) {
// only read data if room in buf
#if defined(STM32F0) || defined(STM32F7) || defined(STM32L4) || defined(STM32H7)
int data = self->uartx->RDR; // clears UART_FLAG_RXNE
self->uartx->ICR = USART_ICR_ORECF; // clear ORE if it was set
#else
int data = self->uartx->DR; // clears UART_FLAG_RXNE
#endif
data &= self->char_mask;
if (self->attached_to_repl && data == mp_interrupt_char) {
// Handle interrupt coming in on a UART REPL
pendsv_kbd_intr();
} else {
if (self->char_width == CHAR_WIDTH_9BIT) {
((uint16_t*)self->read_buf)[self->read_buf_head] = data;
} else {
self->read_buf[self->read_buf_head] = data;
}
self->read_buf_head = next_head;
}
} else { // No room: leave char in buf, disable interrupt
UART_RXNE_IT_DIS(self->uartx);
}
}
}
// If RXNE is clear but ORE set then clear the ORE flag (it's tied to RXNE IRQ)
#if defined(STM32F4)
else if (self->uartx->SR & USART_SR_ORE) {
(void)self->uartx->DR;
}
#else
else if (self->uartx->ISR & USART_ISR_ORE) {
self->uartx->ICR = USART_ICR_ORECF;
}
#endif
// Set user IRQ flags
self->mp_irq_flags = 0;
#if defined(STM32F4)
if (self->uartx->SR & USART_SR_IDLE) {
(void)self->uartx->SR;
(void)self->uartx->DR;
self->mp_irq_flags |= UART_FLAG_IDLE;
}
#else
if (self->uartx->ISR & USART_ISR_IDLE) {
self->uartx->ICR = USART_ICR_IDLECF;
self->mp_irq_flags |= UART_FLAG_IDLE;
}
#endif
// Check the flags to see if the user handler should be called
if (self->mp_irq_trigger & self->mp_irq_flags) {
mp_irq_handler(self->mp_irq_obj);
}
}
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