#include "util.h"
+#include <libopencm3/cm3/cortex.h>
#include <libopencm3/cm3/nvic.h>
#include <libopencm3/cm3/systick.h>
+#include <libopencm3/cm3/scb.h>
#include <libopencm3/stm32/rcc.h>
#include <libopencm3/stm32/desig.h>
#include <libopencm3/stm32/gpio.h>
#include <libopencm3/stm32/timer.h>
#include <libopencm3/stm32/usart.h>
+#include <libopencm3/usb/dfu.h>
#include <libopencm3/usb/usbd.h>
#include <string.h>
+/*** Hardware init ***/
+
static void clock_init(void)
{
rcc_clock_setup_in_hse_8mhz_out_72mhz();
rcc_periph_clock_enable(RCC_GPIOB);
rcc_periph_clock_enable(RCC_GPIOC);
rcc_periph_clock_enable(RCC_USART1);
+ rcc_periph_clock_enable(RCC_USART3);
rcc_periph_clock_enable(RCC_USB);
rcc_periph_reset_pulse(RST_GPIOA);
rcc_periph_reset_pulse(RST_GPIOB);
rcc_periph_reset_pulse(RST_GPIOC);
rcc_periph_reset_pulse(RST_USART1);
+ rcc_periph_reset_pulse(RST_USART3);
rcc_periph_reset_pulse(RST_USB);
}
static void gpio_init(void)
{
// PA9 = TXD1 for debugging console
- gpio_set_mode(GPIOA, GPIO_MODE_OUTPUT_50_MHZ, GPIO_CNF_OUTPUT_ALTFN_PUSHPULL, GPIO9);
-
// PA10 = RXD1 for debugging console
+ gpio_set_mode(GPIOA, GPIO_MODE_OUTPUT_50_MHZ, GPIO_CNF_OUTPUT_ALTFN_PUSHPULL, GPIO9);
gpio_set_mode(GPIOA, GPIO_MODE_INPUT, GPIO_CNF_INPUT_FLOAT, GPIO10);
// PC13 = BluePill LED
gpio_set_mode(GPIOC, GPIO_MODE_OUTPUT_50_MHZ, GPIO_CNF_OUTPUT_PUSHPULL, GPIO13);
gpio_clear(GPIOC, GPIO13);
+
+ // PB0 = yellow LED*, PB1 = green LED*
+ gpio_set_mode(GPIOB, GPIO_MODE_OUTPUT_50_MHZ, GPIO_CNF_OUTPUT_OPENDRAIN, GPIO0 | GPIO1);
+ gpio_set(GPIOB, GPIO0 | GPIO1);
+
+ // PB10 = TXD3 for BSB
+ // PB11 = RXD3 for BSB
+ // FIXME: TX turned off temporarily
+ // gpio_set_mode(GPIOB, GPIO_MODE_OUTPUT_50_MHZ, GPIO_CNF_OUTPUT_ALTFN_OPENDRAIN, GPIO10);
+ gpio_set_mode(GPIOB, GPIO_MODE_INPUT, GPIO_CNF_INPUT_FLOAT, GPIO11);
}
+static void usart_init(void)
+{
+ usart_set_baudrate(USART1, 115200);
+ usart_set_databits(USART1, 8);
+ usart_set_stopbits(USART1, USART_STOPBITS_1);
+ usart_set_mode(USART1, USART_MODE_TX_RX);
+ usart_set_parity(USART1, USART_PARITY_NONE);
+ usart_set_flow_control(USART1, USART_FLOWCONTROL_NONE);
+
+ usart_enable(USART1);
+}
+
+/*** System ticks ***/
+
static volatile u32 ms_ticks;
void sys_tick_handler(void)
static void tick_init(void)
{
- systick_set_frequency(1000, 72000000);
+ systick_set_frequency(1000, CPU_CLOCK_MHZ * 1000000);
systick_counter_enable();
systick_interrupt_enable();
}
;
}
-static void usart_init(void)
+/*** BSB ***/
+
+#define BSB_MAX_SIZE 32
+#define BSB_RX_TIMEOUT 10 // ms
+
+#define DEBUG_BSB
+#ifdef DEBUG_BSB
+#define BSB_DEBUG(x...) debug_printf(x)
+#else
+#define BSB_DEBUG(x...) do { } while (0)
+#endif
+
+static byte bsb_rx_buf[BSB_MAX_SIZE];
+static byte bsb_rx_len;
+static u16 bsb_rx_crc;
+static volatile u32 bsb_rx_timestamp;
+
+// Passing received frames to the main loop
+static byte bsb_rx_frame[BSB_MAX_SIZE];
+static volatile byte bsb_rx_frame_len;
+static byte bsb_rx_frame_led;
+
+struct bsb_stat {
+ u32 rx_noise;
+ u32 rx_errors;
+ u32 rx_invalid;
+ u32 rx_overruns;
+ u32 rx_timeouts;
+ u32 rx_bad_crc;
+ u32 rx_ok;
+};
+
+static struct bsb_stat bsb_stat;
+
+static u16 bsb_crc_update(u16 crc, byte data)
{
- usart_set_baudrate(USART1, 115200);
- usart_set_databits(USART1, 8);
- usart_set_stopbits(USART1, USART_STOPBITS_1);
- usart_set_mode(USART1, USART_MODE_TX_RX);
- usart_set_parity(USART1, USART_PARITY_NONE);
- usart_set_flow_control(USART1, USART_FLOWCONTROL_NONE);
+ crc = crc ^ (data << 8);
+ for (uint i=0; i<8; i++) {
+ if (crc & 0x8000)
+ crc = (crc << 1) ^ 0x1021;
+ else
+ crc <<= 1;
+ }
+ return crc;
+}
- usart_enable(USART1);
+void usart3_isr(void)
+{
+ u32 status = USART_SR(USART3);
+
+ if (status & USART_SR_RXNE) {
+ uint ch = ~usart_recv(USART3) & 0xff;
+ bsb_rx_timestamp = ms_ticks;
+ BSB_DEBUG(" %02x", ch);
+
+ if (status & (USART_SR_FE | USART_SR_ORE | USART_SR_NE)) {
+ bsb_stat.rx_errors++;
+ bsb_rx_len = 0;
+ } else if (!bsb_rx_len) {
+ // Start of frame
+ if (ch == 0xdc) {
+ bsb_rx_buf[bsb_rx_len++] = ch;
+ bsb_rx_crc = bsb_crc_update(0, ch);
+ BSB_DEBUG("<");
+ } else {
+ bsb_stat.rx_noise++;
+ BSB_DEBUG("?");
+ }
+ } else {
+ bsb_rx_buf[bsb_rx_len++] = ch;
+ bsb_rx_crc = bsb_crc_update(bsb_rx_crc, ch);
+ if (bsb_rx_len < 4) {
+ // First three bytes: SOF, source addr, destination addr
+ } else if (bsb_rx_len == 4) {
+ // Received length byte
+ if (bsb_rx_buf[3] < 7 || bsb_rx_buf[3] > BSB_MAX_SIZE) {
+ bsb_stat.rx_invalid++;
+ bsb_rx_len = 0;
+ BSB_DEBUG("!L");
+ }
+ } else if (bsb_rx_len == bsb_rx_buf[3]) {
+ // Received a complete frame: check CRC and pass it to the main loop
+ if (bsb_rx_crc) {
+ bsb_stat.rx_bad_crc++;
+ BSB_DEBUG("!C");
+ } else {
+ if (bsb_rx_frame_len) {
+ // The previous one was not sent yet
+ bsb_stat.rx_overruns++;
+ BSB_DEBUG("!O");
+ } else {
+ memcpy(bsb_rx_frame, bsb_rx_buf, bsb_rx_buf[3]);
+ bsb_rx_frame_len = bsb_rx_buf[3];
+ bsb_stat.rx_ok++;
+ BSB_DEBUG(".");
+ }
+ gpio_clear(GPIOB, GPIO1);
+ bsb_rx_frame_led = 100;
+ }
+ bsb_rx_len = 0;
+ }
+ }
+ }
+}
+
+static void bsb_init(void)
+{
+ usart_set_baudrate(USART3, 4800);
+ usart_set_databits(USART3, 9);
+ usart_set_stopbits(USART3, USART_STOPBITS_1);
+ usart_set_mode(USART3, USART_MODE_RX);
+ usart_set_parity(USART3, USART_PARITY_ODD);
+ usart_set_flow_control(USART3, USART_FLOWCONTROL_NONE);
+
+ usart_enable(USART3);
+ nvic_enable_irq(NVIC_USART3_IRQ);
+ usart_enable_rx_interrupt(USART3);
}
-static const struct usb_device_descriptor dev = {
+/*** USB ***/
+
+static usbd_device *usbd_dev;
+
+static const struct usb_device_descriptor device = {
.bLength = USB_DT_DEVICE_SIZE,
.bDescriptorType = USB_DT_DEVICE,
.bcdUSB = 0x0200,
.endpoint = endpoints,
};
+static const struct usb_dfu_descriptor dfu_function = {
+ .bLength = sizeof(struct usb_dfu_descriptor),
+ .bDescriptorType = DFU_FUNCTIONAL,
+ .bmAttributes = USB_DFU_CAN_DOWNLOAD | USB_DFU_WILL_DETACH,
+ .wDetachTimeout = 255,
+ .wTransferSize = 1024,
+ .bcdDFUVersion = 0x0100,
+};
+
+static const struct usb_interface_descriptor dfu_iface = {
+ .bLength = USB_DT_INTERFACE_SIZE,
+ .bDescriptorType = USB_DT_INTERFACE,
+ .bInterfaceNumber = 1,
+ .bAlternateSetting = 0,
+ .bNumEndpoints = 0,
+ .bInterfaceClass = 0xFE,
+ .bInterfaceSubClass = 1,
+ .bInterfaceProtocol = 1,
+ .iInterface = 0,
+
+ .extra = &dfu_function,
+ .extralen = sizeof(dfu_function),
+};
+
static const struct usb_interface ifaces[] = {{
.num_altsetting = 1,
.altsetting = &iface,
+}, {
+ .num_altsetting = 1,
+ .altsetting = &dfu_iface,
}};
static const struct usb_config_descriptor config = {
.bLength = USB_DT_CONFIGURATION_SIZE,
.bDescriptorType = USB_DT_CONFIGURATION,
.wTotalLength = 0,
- .bNumInterfaces = 1,
+ .bNumInterfaces = 2,
.bConfigurationValue = 1,
.iConfiguration = 0,
.bmAttributes = 0x80,
};
static byte usb_configured;
+static byte usb_rx_pending;
static uint8_t usbd_control_buffer[64];
-static enum usbd_request_return_codes control_cb(usbd_device *usbd_dev,
+static enum usbd_request_return_codes control_cb(
+ usbd_device *dev UNUSED,
struct usb_setup_data *req,
uint8_t **buf,
uint16_t *len,
- void (**complete)(usbd_device *usbd_dev, struct usb_setup_data *req) UNUSED)
+ void (**complete)(usbd_device *dev, struct usb_setup_data *req) UNUSED)
{
if (req->bmRequestType != 0xc0 || req->bRequest != 0x00)
return USBD_REQ_NOTSUPP;
- (void) usbd_dev;
- (void) buf;
- (void) len;
- (void) complete;
- debug_printf("USB: Control request\n");
+ // We support reading of statistics via control requests
+ debug_printf("USB: Reading statistics\n");
+ uint n = MIN(*len, sizeof(bsb_stat));
+ memcpy(*buf, (char *) &bsb_stat, n);
+ *len = n;
- byte *b = *buf;
- b[0] = 0x12;
- b[1] = 0x34;
- b[2] = 0x56;
- b[3] = 0x78;
- if (*len > 4)
- *len = 4;
+ return USBD_REQ_HANDLED;
+}
+
+static void dfu_detach_complete(usbd_device *dev UNUSED, struct usb_setup_data *req UNUSED)
+{
+ // Reset to bootloader, which implements the rest of DFU
+ debug_printf("Switching to DFU\n");
+ debug_flush();
+ scb_reset_core();
+}
+static enum usbd_request_return_codes dfu_control_cb(usbd_device *dev UNUSED,
+ struct usb_setup_data *req,
+ uint8_t **buf UNUSED,
+ uint16_t *len UNUSED,
+ void (**complete)(usbd_device *dev, struct usb_setup_data *req))
+{
+ if (req->bmRequestType != 0x21 || req->bRequest != DFU_DETACH)
+ return USBD_REQ_NOTSUPP;
+
+ *complete = dfu_detach_complete;
return USBD_REQ_HANDLED;
}
-static void ep81_cb(usbd_device *usbd_dev, uint8_t ep UNUSED)
+static void ep81_cb(usbd_device *dev, uint8_t ep UNUSED)
{
byte buf[4];
put_u32_be(buf, ms_ticks);
- usbd_ep_write_packet(usbd_dev, 0x81, buf, sizeof(buf));
+ usbd_ep_write_packet(dev, 0x81, buf, sizeof(buf));
debug_printf("USB: Bulk write\n");
}
-static void set_config_cb(usbd_device *usbd_dev, uint16_t wValue UNUSED)
+static void rx_cb(usbd_device *dev UNUSED, uint8_t ep UNUSED)
+{
+ // Received packet passed through interrupt end-point
+ debug_printf("USB: RX EP done\n");
+ usb_rx_pending = 0;
+}
+
+static void set_config_cb(usbd_device *dev, uint16_t wValue UNUSED)
{
- usbd_register_control_callback(usbd_dev, USB_REQ_TYPE_VENDOR, USB_REQ_TYPE_TYPE, control_cb);
- usbd_ep_setup(usbd_dev, 0x81, USB_ENDPOINT_ATTR_BULK, 64, ep81_cb);
- usbd_ep_setup(usbd_dev, 0x82, USB_ENDPOINT_ATTR_BULK, 64, NULL);
- ep81_cb(usbd_dev, 0);
+ usbd_register_control_callback(dev,
+ USB_REQ_TYPE_VENDOR,
+ USB_REQ_TYPE_TYPE,
+ control_cb);
+ usbd_register_control_callback(dev,
+ USB_REQ_TYPE_CLASS | USB_REQ_TYPE_INTERFACE,
+ USB_REQ_TYPE_TYPE | USB_REQ_TYPE_RECIPIENT,
+ dfu_control_cb);
+ usbd_ep_setup(dev, 0x81, USB_ENDPOINT_ATTR_BULK, 64, ep81_cb);
+ usbd_ep_setup(dev, 0x82, USB_ENDPOINT_ATTR_BULK, 64, rx_cb);
+ ep81_cb(dev, 0);
usb_configured = 1;
}
usb_configured = 0;
}
+static volatile bool usb_event_pending;
+
+void usb_lp_can_rx0_isr(void)
+{
+ /*
+ * We handle USB in the main loop to avoid race conditions between
+ * USB interrupts and other code. However, we need an interrupt to
+ * up the main loop from sleep.
+ *
+ * We set up only the low-priority ISR, because high-priority ISR handles
+ * only double-buffered bulk transfers and isochronous transfers.
+ */
+ nvic_disable_irq(NVIC_USB_LP_CAN_RX0_IRQ);
+ usb_event_pending = 1;
+}
+
+static void usb_init(void)
+{
+ // Simulate USB disconnect
+ gpio_set_mode(GPIOA, GPIO_MODE_OUTPUT_50_MHZ, GPIO_CNF_OUTPUT_OPENDRAIN, GPIO11 | GPIO12);
+ gpio_clear(GPIOA, GPIO11 | GPIO12);
+ delay_ms(1000);
+
+ usbd_dev = usbd_init(
+ &st_usbfs_v1_usb_driver,
+ &device,
+ &config,
+ usb_strings,
+ ARRAY_SIZE(usb_strings),
+ usbd_control_buffer,
+ sizeof(usbd_control_buffer)
+ );
+ usbd_register_reset_callback(usbd_dev, reset_cb);
+ usbd_register_set_config_callback(usbd_dev, set_config_cb);
+ usb_event_pending = 1;
+}
+
+/*** Main ***/
+
int main(void)
{
clock_init();
debug_printf("Hello, kitty!\n");
- // Simulate USB disconnect
- gpio_set_mode(GPIOA, GPIO_MODE_OUTPUT_50_MHZ, GPIO_CNF_OUTPUT_OPENDRAIN, GPIO11 | GPIO12);
- gpio_clear(GPIOA, GPIO11 | GPIO12);
- delay_ms(1000);
+ bsb_init();
+ usb_init();
- usbd_device *usbd_dev = usbd_init(&st_usbfs_v1_usb_driver, &dev, &config, usb_strings, ARRAY_SIZE(usb_strings), usbd_control_buffer, sizeof(usbd_control_buffer));
- usbd_register_reset_callback(usbd_dev, reset_cb);
- usbd_register_set_config_callback(usbd_dev, set_config_cb);
u32 last_ds_step = 0;
for (;;) {
if (ms_ticks - last_ds_step >= 100) {
debug_led_toggle();
+ gpio_toggle(GPIOB, GPIO0);
last_ds_step = ms_ticks;
- if (usb_configured) {
- byte x[4];
- put_u32_be(x, ms_ticks);
- usbd_ep_write_packet(usbd_dev, 0x82, x, 4);
+ }
+
+ if (usb_event_pending) {
+ usbd_poll(usbd_dev);
+ usb_event_pending = 0;
+ nvic_clear_pending_irq(NVIC_USB_LP_CAN_RX0_IRQ);
+ nvic_enable_irq(NVIC_USB_LP_CAN_RX0_IRQ);
+ }
+
+ if (usb_configured) {
+ // Passing of received packets to USB
+ if (!usb_rx_pending) {
+ if (bsb_rx_frame_len) {
+ barrier();
+ usbd_ep_write_packet(usbd_dev, 0x82, bsb_rx_frame, bsb_rx_frame_len);
+ usb_rx_pending = 1;
+ barrier();
+ bsb_rx_frame_len = 0;
+ debug_printf("USB: RX started\n");
+ }
}
}
- // XXX: libopencm3 usbd does not use interrupts at the moment, need to poll...
- // wait_for_interrupt();
- usbd_poll(usbd_dev);
+ // Packet timeouts
+ cm_disable_interrupts();
+ barrier();
+ if (bsb_rx_len && ms_ticks - bsb_rx_timestamp >= BSB_RX_TIMEOUT) {
+ bsb_rx_len = 0;
+ bsb_stat.rx_timeouts++;
+ BSB_DEBUG("!T");
+ }
+ if (bsb_rx_frame_led) {
+ if (!--bsb_rx_frame_led)
+ gpio_set(GPIOB, GPIO1);
+ }
+ cm_enable_interrupts();
+
+ wait_for_interrupt();
}
return 0;