1 /* 2 * Copyright (c) 2020 Google LLC. 3 * 4 * SPDX-License-Identifier: Apache-2.0 5 */ 6 7 #include <soc.h> 8 #include <zephyr/drivers/uart/cdc_acm.h> 9 #include <zephyr/drivers/usb/usb_dc.h> 10 #include <zephyr/init.h> 11 #include <zephyr/usb/class/usb_cdc.h> 12 13 /* 14 * Magic value that causes the bootloader to stay in bootloader mode instead of 15 * starting the application. 16 */ 17 #if CONFIG_BOOTLOADER_BOSSA_ADAFRUIT_UF2 18 #define DOUBLE_TAP_MAGIC 0xf01669ef 19 #elif CONFIG_BOOTLOADER_BOSSA_ARDUINO 20 #define DOUBLE_TAP_MAGIC 0x07738135 21 #else 22 #error Unsupported BOSSA bootloader variant 23 #endif 24 25 #if defined(CONFIG_BOOTLOADER_BOSSA_DEVICE_NAME) 26 bossa_reset(const struct device * dev,uint32_t rate)27static void bossa_reset(const struct device *dev, uint32_t rate) 28 { 29 uint32_t *top; 30 31 if (rate != 1200) { 32 return; 33 } 34 35 /* The programmer set the baud rate to 1200 baud. Reset into the 36 * bootloader. 37 */ 38 usb_dc_detach(); 39 40 top = (uint32_t *)(DT_REG_ADDR(DT_NODELABEL(sram0)) + 41 DT_REG_SIZE(DT_NODELABEL(sram0))); 42 top[-1] = DOUBLE_TAP_MAGIC; 43 44 NVIC_SystemReset(); 45 } 46 bossa_init(void)47static int bossa_init(void) 48 { 49 const struct device *dev = 50 device_get_binding(CONFIG_BOOTLOADER_BOSSA_DEVICE_NAME); 51 52 if (dev == NULL) { 53 return -ENODEV; 54 } 55 56 return cdc_acm_dte_rate_callback_set(dev, bossa_reset); 57 } 58 59 SYS_INIT(bossa_init, APPLICATION, 0); 60 61 #endif /* CONFIG_BOOTLOADER_BOSSA_DEVICE_NAME */ 62
