void gdb_if_putchar(unsigned char c, int flush)
{
buffer_in[count_in++] = c;
if(flush || (count_in == CDCACM_PACKET_SIZE)) {
/* Refuse to send if USB isn't configured, and
* don't bother if nobody's listening */
if((cdcacm_get_config() != 1) || !cdcacm_get_dtr()) {
count_in = 0;
return;
}
while(usbd_ep_write_packet(usbdev, CDCACM_GDB_ENDPOINT,
buffer_in, count_in) <= 0);
if (flush && (count_in == CDCACM_PACKET_SIZE)) {
/* We need to send an empty packet for some hosts
* to accept this as a complete transfer. */
/* libopencm3 needs a change for us to confirm when
* that transfer is complete, so we just send a packet
* containing a null byte for now.
*/
while (usbd_ep_write_packet(usbdev, CDCACM_GDB_ENDPOINT,
"\0", 1) <= 0);
}
count_in = 0;
}
}
/*
* Read a character from the UART RX and stuff it in a software FIFO.
* Allowed to read from FIFO out pointer, but not write to it.
* Allowed to write to FIFO in pointer.
*/
void USBUART_ISR(void)
{
int flush = uart_is_interrupt_source(USBUART, UART_INT_RT);
while (!uart_is_rx_fifo_empty(USBUART)) {
char c = uart_recv(USBUART);
/* If the next increment of rx_in would put it at the same point
* as rx_out, the FIFO is considered full.
*/
if (((buf_rx_in + 1) % FIFO_SIZE) != buf_rx_out)
{
/* insert into FIFO */
buf_rx[buf_rx_in++] = c;
/* wrap out pointer */
if (buf_rx_in >= FIFO_SIZE)
{
buf_rx_in = 0;
}
} else {
flush = 1;
}
}
if (flush) {
/* forcibly empty fifo if no USB endpoint */
if (cdcacm_get_config() != 1)
{
buf_rx_out = buf_rx_in;
return;
}
uint8_t packet_buf[CDCACM_PACKET_SIZE];
uint8_t packet_size = 0;
uint8_t buf_out = buf_rx_out;
/* copy from uart FIFO into local usb packet buffer */
while (buf_rx_in != buf_out && packet_size < CDCACM_PACKET_SIZE)
{
packet_buf[packet_size++] = buf_rx[buf_out++];
/* wrap out pointer */
if (buf_out >= FIFO_SIZE)
{
buf_out = 0;
}
}
/* advance fifo out pointer by amount written */
buf_rx_out += usbd_ep_write_packet(usbdev,
CDCACM_UART_ENDPOINT, packet_buf, packet_size);
buf_rx_out %= FIFO_SIZE;
}
}
unsigned char gdb_if_getchar(void)
{
while(tail_out == head_out) {
/* Detach if port closed */
if(!cdcacm_get_dtr())
return 0x04;
while(cdcacm_get_config() != 1);
}
return buffer_out[tail_out++ % sizeof(buffer_out)];
}
void cdcacm_init(void) {
//system setup
rcc_peripheral_enable_clock(&RCC_AHB1ENR, RCC_AHB1ENR_IOPAEN);
rcc_peripheral_enable_clock(&RCC_AHB2ENR, RCC_AHB2ENR_OTGFSEN);
gpio_mode_setup(GPIOA, GPIO_MODE_AF, GPIO_PUPD_NONE,
GPIO9 | GPIO11 | GPIO12);
gpio_set_af(GPIOA, GPIO_AF10, GPIO9 | GPIO11 | GPIO12);
cdcacm_usb_init();
nvic_set_priority(NVIC_OTG_FS_IRQ, IRQ_PRI_USB);
nvic_enable_irq(NVIC_OTG_FS_IRQ);
while (cdcacm_get_config() != 1) { wait(1); }; //wait until usb is configured
}
void gdb_if_putchar(unsigned char c, int flush)
{
buffer_in[count_in++] = c;
if(flush || (count_in == CDCACM_PACKET_SIZE)) {
/* Refuse to send if USB isn't configured, and
* don't bother if nobody's listening */
if((cdcacm_get_config() != 1) || !cdcacm_get_dtr()) {
count_in = 0;
return;
}
while(usbd_ep_write_packet(usbdev, CDCACM_GDB_ENDPOINT,
buffer_in, count_in) <= 0);
count_in = 0;
}
}
unsigned char gdb_if_getchar(void)
{
while(!(out_ptr < count_out)) {
/* Detach if port closed */
if(!cdcacm_get_dtr())
return 0x04;
while(cdcacm_get_config() != 1);
count_out = usbd_ep_read_packet(usbdev, CDCACM_GDB_ENDPOINT,
buffer_out, CDCACM_PACKET_SIZE);
out_ptr = 0;
}
return buffer_out[out_ptr++];
}
unsigned char gdb_if_getchar_to(int timeout)
{
platform_timeout t;
platform_timeout_set(&t, timeout);
if(head_out == tail_out) do {
/* Detach if port closed */
if(!cdcacm_get_dtr())
return 0x04;
while(cdcacm_get_config() != 1);
} while(!platform_timeout_is_expired(&t) && head_out == tail_out);
if(head_out != tail_out)
return gdb_if_getchar();
return -1;
}
static void gdb_if_update_buf(void)
{
while (cdcacm_get_config() != 1);
#ifdef STM32F4
asm volatile ("cpsid i; isb");
if (count_new) {
memcpy(buffer_out, double_buffer_out, count_new);
count_out = count_new;
count_new = 0;
out_ptr = 0;
usbd_ep_nak_set(usbdev, CDCACM_GDB_ENDPOINT, 0);
}
asm volatile ("cpsie i; isb");
#else
count_out = usbd_ep_read_packet(usbdev, CDCACM_GDB_ENDPOINT,
buffer_out, CDCACM_PACKET_SIZE);
out_ptr = 0;
#endif
}
unsigned char gdb_if_getchar(void)
{
while(!(out_ptr < count_out)) {
/* Detach if port closed */
if(!cdcacm_get_dtr())
return 0x04;
while(cdcacm_get_config() != 1);
if (count_new) {
memcpy(buffer_out, double_buffer_out,count_new);
count_out = count_new;
count_new = 0;
out_ptr = 0;
usbd_ep_nak_set(usbdev, CDCACM_GDB_ENDPOINT, 0);
}
}
return buffer_out[out_ptr++];
}
/*
* Runs deferred processing for usb uart rx, draining RX FIFO by sending
* characters to host PC via CDCACM. Allowed to read from FIFO in pointer,
* but not write to it. Allowed to write to FIFO out pointer.
*/
static void usbuart_run(void)
{
/* forcibly empty fifo if no USB endpoint */
if (cdcacm_get_config() != 1)
{
buf_rx_out = buf_rx_in;
}
/* if fifo empty, nothing further to do */
if (buf_rx_in == buf_rx_out) {
/* turn off LED, disable IRQ */
timer_disable_irq(USBUSART_TIM, TIM_DIER_UIE);
gpio_clear(LED_PORT_UART, LED_UART);
}
else
{
uint8_t packet_buf[CDCACM_PACKET_SIZE];
uint8_t packet_size = 0;
uint8_t buf_out = buf_rx_out;
/* copy from uart FIFO into local usb packet buffer */
while (buf_rx_in != buf_out && packet_size < CDCACM_PACKET_SIZE)
{
packet_buf[packet_size++] = buf_rx[buf_out++];
/* wrap out pointer */
if (buf_out >= FIFO_SIZE)
{
buf_out = 0;
}
}
/* advance fifo out pointer by amount written */
buf_rx_out += usbd_ep_write_packet(usbdev,
CDCACM_UART_ENDPOINT, packet_buf, packet_size);
buf_rx_out %= FIFO_SIZE;
}
}
unsigned char gdb_if_getchar_to(int timeout)
{
timeout_counter = timeout/100;
if(!(out_ptr < count_out)) do {
/* Detach if port closed */
if(!cdcacm_get_dtr())
return 0x04;
while(cdcacm_get_config() != 1);
if (count_new) {
memcpy(buffer_out, double_buffer_out,count_new);
count_out = count_new;
count_new = 0;
out_ptr = 0;
usbd_ep_nak_set(usbdev, CDCACM_GDB_ENDPOINT, 0);
}
} while(timeout_counter && !(out_ptr < count_out));
if(out_ptr < count_out)
return gdb_if_getchar();
return -1;
}