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#include "arch.h"
#include "arch/stm32l4xxx/peripherals/clock.h"
#include "arch/stm32l4xxx/peripherals/dma.h"
#include "arch/stm32l4xxx/peripherals/gpio.h"
#include "arch/stm32l4xxx/peripherals/system.h"
#include "arch/stm32l4xxx/peripherals/usart.h"
#include "arch/stm32l4xxx/peripherals/nvic.h"
#include "arch/stm32l4xxx/peripherals/irq.h"
#include "kern/dma/dma_manager.h"
#include "kern/delay.h"
#include "kern/mem.h"
#include "kern/spin.h"
#include "kern/string.h"
/** Overrides the default systick irq handler. */
void on_systick()
{
static int is_on = 0;
__IO gpio_port_t* port_b = enable_gpio(GPIO_PORT_B);
gpio_output_pin_t pin3 = set_gpio_pin_output(port_b, PIN_3);
if (is_on) {
pin_off(pin3);
} else {
pin_on(pin3);
}
is_on = ! is_on;
}
void setup_usart2(uint32_t baud_rate)
{
__IO gpio_port_t* port_a = enable_gpio(GPIO_PORT_A);
enable_hsi(&RCC, true);
set_usart2_clock_src(&RCC, USART_CLK_SRC_HSI16);
set_usart2_clock_enabled(&RCC, USART_CLK_SRC_HSI16);
set_gpio_pin_mode(port_a, PIN_2, MODE_ALTERNATE);
set_gpio_pin_mode(port_a, PIN_15, MODE_ALTERNATE);
set_gpio_alternate_function(port_a, PIN_2, AFN_7);
set_gpio_alternate_function(port_a, PIN_15, AFN_3);
/* De-assert reset of USART2 */
regset(RCC.apb1rst1_r, rcc_usart2rst, 0);
USART2.c_r1 = 0;
USART2.c_r2 = 0;
USART2.c_r3 = 0;
usart_set_divisor(&USART2, 16000000 / baud_rate);
}
#ifdef ARCH_STM32L4
/* Main function. This gets executed from the interrupt vector defined above. */
int main()
{
/* Enable a higher clock frequency. */
set_system_clock_MHz(80);
setup_usart2(115200);
regset(USART2.c_r1, usart_txeie, 1);
regset(USART2.c_r1, usart_rxneie, 1);
usart_enable_dma(&USART2, USART_ENABLE_TX);
usart_set_enabled(&USART2, USART_ENABLE_TX | USART_ENABLE_RX);
dma_opts_t opts = DEFAULT_DMA_OPTS;
opts.transfer_complete_interrupt_enable = 1;
int ec = 0;
dma_mem2p_channel_t dma_chan =
select_dma_channel_mem2p(DMA1_PERIPH_USART2_TX, &opts, &ec);
enable_interrupt(dma_channel_get_interrupt(dma_chan.c_));
if (ec) {
usart_printf(&USART2, "Select DMA channel failed :( %d\n", ec);
for (;;);
}
// const char* thing = "Good Thing This Works!";
char* str = halloc(128);
kstrcpy(str, "Hello, Heap!");
usart_printf(&USART2, "DATA_SEGMENT_START %p\n", &DATA_SEGMENT_START);
usart_printf(&USART2, "DATA_SEGMENT_STOP: %p\n", &DATA_SEGMENT_STOP);
usart_printf(&USART2, "str at: %p\n", str);
usart_printf(&USART2, "str: %s\n", str);
// usart_printf(&USART2, "%s\n", thing);
// regset(USART2.ic_r, usart_tccf, 1);
// dma_mem2p_initiate_transfer(dma_chan, thing, strlen(thing));
__IO gpio_port_t* port_b = enable_gpio(GPIO_PORT_B);
gpio_output_pin_t pin3 = set_gpio_pin_output(port_b, PIN_3);
pin_on(pin3);
// usart_printf(&USART2, "Start Configuring Countdown!\n");
/* Set the countdown to start from 1,000,0000. */
SCB.strv_r = 10000000;
/* Enable interrupts. */
regset(SCB.stcs_r, scb_tickint, 1);
/* Start the systick. */
regset(SCB.stcs_r, scb_enable, 1);
// usart_printf(&USART2, "Start Countdown Started!\n");
}
#endif
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