mongoose/examples/stm32/nucleo-f429zi-baremetal/hal.h
2023-02-10 15:53:55 -03:00

141 lines
5.5 KiB
C

// Copyright (c) 2022 Cesanta Software Limited
// All rights reserved
// https://www.st.com/resource/en/reference_manual/dm00031020-stm32f405-415-stm32f407-417-stm32f427-437-and-stm32f429-439-advanced-arm-based-32-bit-mcus-stmicroelectronics.pdf
#pragma once
#include <stm32f429xx.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <string.h>
#define BIT(x) (1UL << (x))
#define SETBITS(R, CLEARMASK, SETMASK) (R) = ((R) & ~(CLEARMASK)) | (SETMASK)
#define PIN(bank, num) ((((bank) - 'A') << 8) | (num))
#define PINNO(pin) (pin & 255)
#define PINBANK(pin) (pin >> 8)
// 6.3.3: APB1 clock <= 45MHz; APB2 clock <= 90MHz
// 3.5.1, Table 11: configure flash latency (WS) in accordance to clock freq
// 33.4: The AHB clock must be at least 25 MHz when Ethernet is used
enum { APB1_PRE = 5 /* AHB clock / 4 */, APB2_PRE = 4 /* AHB clock / 2 */ };
enum { PLL_HSI = 16, PLL_M = 8, PLL_N = 180, PLL_P = 2 }; // Run at 180 Mhz
#define FLASH_LATENCY 5
#define SYS_FREQUENCY ((PLL_HSI * PLL_N / PLL_M / PLL_P) * 1000000)
#define APB2_FREQUENCY (SYS_FREQUENCY / (BIT(APB2_PRE - 3)))
#define APB1_FREQUENCY (SYS_FREQUENCY / (BIT(APB1_PRE - 3)))
static inline void spin(volatile uint32_t count) {
while (count--) (void) 0;
}
enum { GPIO_MODE_INPUT, GPIO_MODE_OUTPUT, GPIO_MODE_AF, GPIO_MODE_ANALOG };
enum { GPIO_OTYPE_PUSH_PULL, GPIO_OTYPE_OPEN_DRAIN };
enum { GPIO_SPEED_LOW, GPIO_SPEED_MEDIUM, GPIO_SPEED_HIGH, GPIO_SPEED_INSANE };
enum { GPIO_PULL_NONE, GPIO_PULL_UP, GPIO_PULL_DOWN };
#define GPIO(N) ((GPIO_TypeDef *) (0x40020000 + 0x400 * (N)))
static GPIO_TypeDef *gpio_bank(uint16_t pin) { return GPIO(PINBANK(pin)); }
static inline void gpio_toggle(uint16_t pin) {
GPIO_TypeDef *gpio = gpio_bank(pin);
uint32_t mask = BIT(PINNO(pin));
gpio->BSRR = mask << (gpio->ODR & mask ? 16 : 0);
}
static inline int gpio_read(uint16_t pin) {
return gpio_bank(pin)->IDR & BIT(PINNO(pin)) ? 1 : 0;
}
static inline void gpio_write(uint16_t pin, bool val) {
GPIO_TypeDef *gpio = gpio_bank(pin);
gpio->BSRR = BIT(PINNO(pin)) << (val ? 0 : 16);
}
static inline void gpio_init(uint16_t pin, uint8_t mode, uint8_t type,
uint8_t speed, uint8_t pull, uint8_t af) {
GPIO_TypeDef *gpio = gpio_bank(pin);
uint8_t n = (uint8_t) (PINNO(pin));
RCC->AHB1ENR |= BIT(PINBANK(pin)); // Enable GPIO clock
SETBITS(gpio->OTYPER, 1UL << n, ((uint32_t) type) << n);
SETBITS(gpio->OSPEEDR, 3UL << (n * 2), ((uint32_t) speed) << (n * 2));
SETBITS(gpio->PUPDR, 3UL << (n * 2), ((uint32_t) pull) << (n * 2));
SETBITS(gpio->AFR[n >> 3], 15UL << ((n & 7) * 4),
((uint32_t) af) << ((n & 7) * 4));
SETBITS(gpio->MODER, 3UL << (n * 2), ((uint32_t) mode) << (n * 2));
}
static inline void gpio_input(uint16_t pin) {
gpio_init(pin, GPIO_MODE_INPUT, GPIO_OTYPE_PUSH_PULL, GPIO_SPEED_HIGH,
GPIO_PULL_NONE, 0);
}
static inline void gpio_output(uint16_t pin) {
gpio_init(pin, GPIO_MODE_OUTPUT, GPIO_OTYPE_PUSH_PULL, GPIO_SPEED_HIGH,
GPIO_PULL_NONE, 0);
}
static inline void irq_exti_attach(uint16_t pin) {
uint8_t bank = (uint8_t) (PINBANK(pin)), n = (uint8_t) (PINNO(pin));
SYSCFG->EXTICR[n / 4] &= ~(15UL << ((n % 4) * 4));
SYSCFG->EXTICR[n / 4] |= (uint32_t) (bank << ((n % 4) * 4));
EXTI->IMR |= BIT(n);
EXTI->RTSR |= BIT(n);
EXTI->FTSR |= BIT(n);
int irqvec = n < 5 ? 6 + n : n < 10 ? 23 : 40; // IRQ vector index, 10.1.2
NVIC_SetPriority(irqvec, 3);
NVIC_EnableIRQ(irqvec);
}
#ifndef UART_DEBUG
#define UART_DEBUG USART3
#endif
static inline void uart_init(USART_TypeDef *uart, unsigned long baud) {
// https://www.st.com/resource/en/datasheet/stm32f429zi.pdf
uint8_t af = 7; // Alternate function
uint16_t rx = 0, tx = 0; // pins
uint32_t freq = 0; // Bus frequency. UART1 is on APB2, rest on APB1
if (uart == USART1) freq = APB2_FREQUENCY, RCC->APB2ENR |= BIT(4);
if (uart == USART2) freq = APB1_FREQUENCY, RCC->APB1ENR |= BIT(17);
if (uart == USART3) freq = APB1_FREQUENCY, RCC->APB1ENR |= BIT(18);
if (uart == USART1) tx = PIN('A', 9), rx = PIN('A', 10);
if (uart == USART2) tx = PIN('A', 2), rx = PIN('A', 3);
if (uart == USART3) tx = PIN('D', 8), rx = PIN('D', 9);
gpio_init(tx, GPIO_MODE_AF, GPIO_OTYPE_PUSH_PULL, GPIO_SPEED_HIGH, 0, af);
gpio_init(rx, GPIO_MODE_AF, GPIO_OTYPE_PUSH_PULL, GPIO_SPEED_HIGH, 0, af);
uart->CR1 = 0; // Disable this UART
uart->BRR = freq / baud; // Set baud rate
uart->CR1 |= BIT(13) | BIT(2) | BIT(3); // Set UE, RE, TE
}
static inline void uart_write_byte(USART_TypeDef *uart, uint8_t byte) {
uart->DR = byte;
while ((uart->SR & BIT(7)) == 0) spin(1);
}
static inline void uart_write_buf(USART_TypeDef *uart, char *buf, size_t len) {
while (len-- > 0) uart_write_byte(uart, *(uint8_t *) buf++);
}
static inline int uart_read_ready(USART_TypeDef *uart) {
return uart->SR & BIT(5); // If RXNE bit is set, data is ready
}
static inline uint8_t uart_read_byte(USART_TypeDef *uart) {
return (uint8_t) (uart->DR & 255);
}
static inline void rng_init(void) {
RCC->AHB2ENR |= RCC_AHB2ENR_RNGEN;
RNG->CR |= RNG_CR_RNGEN;
}
static inline uint32_t rng_read(void) {
while ((RNG->SR & RNG_SR_DRDY) == 0) (void) 0;
return RNG->DR;
}
#define UUID ((uint8_t *) UID_BASE) // Unique 96-bit chip ID. TRM 39.1
// Helper macro for MAC generation
#define GENERATE_LOCALLY_ADMINISTERED_MAC() \
{ \
2, UUID[0] ^ UUID[1], UUID[2] ^ UUID[3], UUID[4] ^ UUID[5], \
UUID[6] ^ UUID[7] ^ UUID[8], UUID[9] ^ UUID[10] ^ UUID[11] \
}