/* * This file is part of the Black Magic Debug project. * * Copyright (C) 2011 Black Sphere Technologies Ltd. * Written by Gareth McMullin * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see . */ /* This file implements a transparent channel over which the GDB Remote * Serial Debugging protocol is implemented. This implementation for STM32 * uses the USB CDC-ACM device bulk endpoints to implement the channel. */ #include "general.h" #include "cdcacm.h" #include "gdb_if.h" static uint32_t count_out; static uint32_t count_in; static uint32_t out_ptr; static uint8_t buffer_out[CDCACM_PACKET_SIZE]; static uint8_t buffer_in[CDCACM_PACKET_SIZE]; #ifdef STM32F4 static volatile uint32_t count_new; static uint8_t double_buffer_out[CDCACM_PACKET_SIZE]; #endif 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; } } #ifdef STM32F4 void gdb_usb_out_cb(usbd_device *dev, uint8_t ep) { (void)ep; usbd_ep_nak_set(dev, CDCACM_GDB_ENDPOINT, 1); count_new = usbd_ep_read_packet(dev, CDCACM_GDB_ENDPOINT, double_buffer_out, CDCACM_PACKET_SIZE); if(!count_new) { usbd_ep_nak_set(dev, CDCACM_GDB_ENDPOINT, 0); } } #endif 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; gdb_if_update_buf(); } return buffer_out[out_ptr++]; } unsigned char gdb_if_getchar_to(int timeout) { platform_timeout_set(timeout); if (!(out_ptr < count_out)) do { /* Detach if port closed */ if (!cdcacm_get_dtr()) return 0x04; gdb_if_update_buf(); } while (!platform_timeout_is_expired() && !(out_ptr < count_out)); if(out_ptr < count_out) return gdb_if_getchar(); return -1; }