// // Copyright 2010 Ettus Research LLC // /* * Copyright 2007,2008 Free Software Foundation, Inc. * * 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 . */ #ifdef HAVE_CONFIG_H #include "config.h" #endif #define DEBUG_MODE 0 //0 for normal operation #include #include #include "u2_init.h" #include "memory_map.h" #include "spi.h" #include "hal_io.h" #include "buffer_pool.h" #include "pic.h" #include #include "ethernet.h" #include "nonstdio.h" #include "dbsm.h" #include #include #include "memcpy_wa.h" #include #include #include #include "clocks.h" #include #include "usrp2/fw_common.h" #include #include #include #include #include #include /* * Full duplex Tx and Rx between ethernet and DSP pipelines * * Buffer 1 is used by the cpu to send frames to the host. * Buffers 2 and 3 are used to double-buffer the DSP Rx to eth flow * Buffers 4 and 5 are used to double-buffer the eth to DSP Tx eth flow */ //#define CPU_RX_BUF 0 // eth -> cpu #define DSP_RX_BUF_0 2 // dsp rx -> eth (double buffer) #define DSP_RX_BUF_1 3 // dsp rx -> eth #define DSP_TX_BUF_0 4 // eth -> dsp tx (double buffer) #define DSP_TX_BUF_1 5 // eth -> dsp tx /* * ================================================================ * configure DSP TX double buffering state machine (eth -> dsp) * ================================================================ */ // DSP Tx reads ethernet header words #define DSP_TX_FIRST_LINE ((sizeof(padded_eth_hdr_t) + sizeof(struct ip_hdr) + sizeof(struct udp_hdr))/sizeof(uint32_t)) // Receive from ethernet buf_cmd_args_t dsp_tx_recv_args = { PORT_ETH, 0, BP_LAST_LINE }; // send to DSP Tx buf_cmd_args_t dsp_tx_send_args = { PORT_DSP, DSP_TX_FIRST_LINE, // starts just past transport header 0 // filled in from last_line register }; dbsm_t dsp_tx_sm; // the state machine /* * ================================================================ * configure DSP RX double buffering state machine (dsp -> eth) * ================================================================ */ typedef struct{ uint32_t control_word; uint32_t vrt_header[]; } rx_dsp_buff_t; #define MK_RX_CTRL_WORD(num_words) (((num_words)*sizeof(uint32_t)) | (1 << 16)) // DSP Rx writes ethernet header words #define DSP_RX_FIRST_LINE 1 //1 = number of control words (see above) // receive from DSP buf_cmd_args_t dsp_rx_recv_args = { PORT_DSP, DSP_RX_FIRST_LINE, BP_LAST_LINE }; // send to ETH buf_cmd_args_t dsp_rx_send_args = { PORT_ETH, 0, // starts with ethernet header in line 0 0, // filled in from list_line register }; dbsm_t dsp_rx_sm; // the state machine // The mac address of the host we're sending to. eth_mac_addr_t host_mac_addr; //controls continuous streaming... static bool auto_reload_command = false; static size_t streaming_items_per_frame = 0; static int streaming_frame_count = 0; #define FRAMES_PER_CMD 2 static void setup_network(void); static void setup_vrt(void); // ---------------------------------------------------------------- // the fast-path setup global variables // ---------------------------------------------------------------- static eth_mac_addr_t fp_mac_addr_src, fp_mac_addr_dst; static struct socket_address fp_socket_src, fp_socket_dst; // ---------------------------------------------------------------- void start_rx_streaming_cmd(void); void stop_rx_cmd(void); static void print_ip_addr(const void *t){ uint8_t *p = (uint8_t *)t; printf("%d.%d.%d.%d", p[0], p[1], p[2], p[3]); } void handle_udp_data_packet( struct socket_address src, struct socket_address dst, unsigned char *payload, int payload_len ){ //store the 2nd word as the following: streaming_items_per_frame = ((uint32_t *)payload)[1]; //its a tiny payload, load the fast-path variables fp_mac_addr_src = *ethernet_mac_addr(); arp_cache_lookup_mac(&src.addr, &fp_mac_addr_dst); fp_socket_src = dst; fp_socket_dst = src; printf("Storing for fast path:\n"); printf(" source mac addr: "); print_mac_addr(fp_mac_addr_src.addr); newline(); printf(" source ip addr: "); print_ip_addr(&fp_socket_src.addr); newline(); printf(" source udp port: %d\n", fp_socket_src.port); printf(" destination mac addr: "); print_mac_addr(fp_mac_addr_dst.addr); newline(); printf(" destination ip addr: "); print_ip_addr(&fp_socket_dst.addr); newline(); printf(" destination udp port: %d\n", fp_socket_dst.port); newline(); //setup network and vrt setup_network(); setup_vrt(); // kick off the state machine dbsm_start(&dsp_rx_sm); } static void inline issue_stream_command(size_t nsamps, bool now, bool chain, uint32_t secs, uint32_t ticks, bool start){ //printf("Stream cmd: nsamps %d, now %d, chain %d, secs %u, ticks %u\n", (int)nsamps, now, chain, secs, ticks); sr_rx_ctrl->cmd = MK_RX_CMD(nsamps, now, chain); if (start) dbsm_start(&dsp_rx_sm); sr_rx_ctrl->time_secs = secs; sr_rx_ctrl->time_ticks = ticks; // enqueue command } #define OTW_GPIO_BANK_TO_NUM(bank) \ (((bank) == USRP2_DIR_RX)? (GPIO_RX_BANK) : (GPIO_TX_BANK)) void handle_udp_ctrl_packet( struct socket_address src, struct socket_address dst, unsigned char *payload, int payload_len ){ //printf("Got ctrl packet #words: %d\n", (int)payload_len); if (payload_len < sizeof(usrp2_ctrl_data_t)){ //TODO send err packet return; } //setup the input and output data usrp2_ctrl_data_t *ctrl_data_in = (usrp2_ctrl_data_t *)payload; usrp2_ctrl_data_t ctrl_data_out = { .id=USRP2_CTRL_ID_HUH_WHAT, .seq=ctrl_data_in->seq }; //handle the data based on the id switch(ctrl_data_in->id){ /******************************************************************* * Addressing ******************************************************************/ case USRP2_CTRL_ID_GIVE_ME_YOUR_IP_ADDR_BRO: ctrl_data_out.id = USRP2_CTRL_ID_THIS_IS_MY_IP_ADDR_DUDE; memcpy(&ctrl_data_out.data.ip_addr, get_ip_addr(), sizeof(struct ip_addr)); break; case USRP2_CTRL_ID_HERE_IS_A_NEW_IP_ADDR_BRO: ctrl_data_out.id = USRP2_CTRL_ID_THIS_IS_MY_IP_ADDR_DUDE; set_ip_addr((struct ip_addr *)&ctrl_data_in->data.ip_addr); memcpy(&ctrl_data_out.data.ip_addr, get_ip_addr(), sizeof(struct ip_addr)); break; case USRP2_CTRL_ID_GIVE_ME_YOUR_MAC_ADDR_BRO: ctrl_data_out.id = USRP2_CTRL_ID_THIS_IS_MY_MAC_ADDR_DUDE; memcpy(&ctrl_data_out.data.mac_addr, ethernet_mac_addr(), sizeof(eth_mac_addr_t)); break; case USRP2_CTRL_ID_HERE_IS_A_NEW_MAC_ADDR_BRO: ctrl_data_out.id = USRP2_CTRL_ID_THIS_IS_MY_MAC_ADDR_DUDE; ethernet_set_mac_addr((eth_mac_addr_t *)&ctrl_data_in->data.mac_addr); memcpy(&ctrl_data_out.data.mac_addr, ethernet_mac_addr(), sizeof(eth_mac_addr_t)); break; case USRP2_CTRL_ID_GIVE_ME_YOUR_DBOARD_IDS_BRO: ctrl_data_out.id = USRP2_CTRL_ID_THESE_ARE_MY_DBOARD_IDS_DUDE; ctrl_data_out.data.dboard_ids.tx_id = read_dboard_eeprom(I2C_ADDR_TX_A); ctrl_data_out.data.dboard_ids.rx_id = read_dboard_eeprom(I2C_ADDR_RX_A); break; /******************************************************************* * SPI ******************************************************************/ case USRP2_CTRL_ID_TRANSACT_ME_SOME_SPI_BRO:{ //transact uint32_t result = spi_transact( (ctrl_data_in->data.spi_args.readback == 0)? SPI_TXONLY : SPI_TXRX, ctrl_data_in->data.spi_args.dev, //which device ctrl_data_in->data.spi_args.data, //32 bit data ctrl_data_in->data.spi_args.num_bits, //length in bits (ctrl_data_in->data.spi_args.mosi_edge == USRP2_CLK_EDGE_RISE)? SPIF_PUSH_FALL : SPIF_PUSH_RISE | (ctrl_data_in->data.spi_args.miso_edge == USRP2_CLK_EDGE_RISE)? SPIF_LATCH_RISE : SPIF_LATCH_FALL ); //load output ctrl_data_out.data.spi_args.data = result; ctrl_data_out.id = USRP2_CTRL_ID_OMG_TRANSACTED_SPI_DUDE; } break; /******************************************************************* * I2C ******************************************************************/ case USRP2_CTRL_ID_DO_AN_I2C_READ_FOR_ME_BRO:{ uint8_t num_bytes = ctrl_data_in->data.i2c_args.bytes; i2c_read( ctrl_data_in->data.i2c_args.addr, ctrl_data_out.data.i2c_args.data, num_bytes ); ctrl_data_out.id = USRP2_CTRL_ID_HERES_THE_I2C_DATA_DUDE; ctrl_data_out.data.i2c_args.bytes = num_bytes; } break; case USRP2_CTRL_ID_WRITE_THESE_I2C_VALUES_BRO:{ uint8_t num_bytes = ctrl_data_in->data.i2c_args.bytes; i2c_write( ctrl_data_in->data.i2c_args.addr, ctrl_data_in->data.i2c_args.data, num_bytes ); ctrl_data_out.id = USRP2_CTRL_ID_COOL_IM_DONE_I2C_WRITE_DUDE; ctrl_data_out.data.i2c_args.bytes = num_bytes; } break; /******************************************************************* * AUX DAC/ADC ******************************************************************/ case USRP2_CTRL_ID_WRITE_THIS_TO_THE_AUX_DAC_BRO: if (ctrl_data_in->data.aux_args.dir == USRP2_DIR_RX){ lsdac_write_rx( ctrl_data_in->data.aux_args.which, ctrl_data_in->data.aux_args.value ); } if (ctrl_data_in->data.aux_args.dir == USRP2_DIR_TX){ lsdac_write_tx( ctrl_data_in->data.aux_args.which, ctrl_data_in->data.aux_args.value ); } ctrl_data_out.id = USRP2_CTRL_ID_DONE_WITH_THAT_AUX_DAC_DUDE; break; case USRP2_CTRL_ID_READ_FROM_THIS_AUX_ADC_BRO: if (ctrl_data_in->data.aux_args.dir == USRP2_DIR_RX){ ctrl_data_out.data.aux_args.value = lsadc_read_rx( ctrl_data_in->data.aux_args.which ); } if (ctrl_data_in->data.aux_args.dir == USRP2_DIR_TX){ ctrl_data_out.data.aux_args.value = lsadc_read_tx( ctrl_data_in->data.aux_args.which ); } ctrl_data_out.id = USRP2_CTRL_ID_DONE_WITH_THAT_AUX_ADC_DUDE; break; /******************************************************************* * Streaming ******************************************************************/ case USRP2_CTRL_ID_SEND_STREAM_COMMAND_FOR_ME_BRO:{ //issue two commands and set the auto-reload flag if (ctrl_data_in->data.stream_cmd.continuous){ printf("Setting up continuous streaming...\n"); printf("items per frame: %d\n", (int)streaming_items_per_frame); auto_reload_command = true; streaming_frame_count = FRAMES_PER_CMD; issue_stream_command( streaming_items_per_frame * FRAMES_PER_CMD, (ctrl_data_in->data.stream_cmd.now == 0)? false : true, //now true, //chain ctrl_data_in->data.stream_cmd.secs, ctrl_data_in->data.stream_cmd.ticks, true //start ); issue_stream_command( streaming_items_per_frame * FRAMES_PER_CMD, true, //now true, //chain 0, 0, //time does not matter false ); } //issue regular stream commands (split commands if too large) else{ auto_reload_command = false; size_t num_samps = ctrl_data_in->data.stream_cmd.num_samps; if (num_samps == 0) num_samps = 1; //FIXME hack, zero is used when stopping continuous streaming but it somehow makes it inifinite bool chain = num_samps > MAX_SAMPLES_PER_CMD; issue_stream_command( (chain)? streaming_items_per_frame : num_samps, //nsamps (ctrl_data_in->data.stream_cmd.now == 0)? false : true, //now (ctrl_data_in->data.stream_cmd.chain == 0)? chain : true, //chain ctrl_data_in->data.stream_cmd.secs, ctrl_data_in->data.stream_cmd.ticks, false ); //handle rest of the samples that did not fit into one cmd while(chain){ num_samps -= MAX_SAMPLES_PER_CMD; chain = num_samps > MAX_SAMPLES_PER_CMD; issue_stream_command( (chain)? streaming_items_per_frame : num_samps, //nsamps true, //now (ctrl_data_in->data.stream_cmd.chain == 0)? chain : true, //chain 0, 0, //time does not matter false ); } } ctrl_data_out.id = USRP2_CTRL_ID_GOT_THAT_STREAM_COMMAND_DUDE; break; } /******************************************************************* * Peek and Poke Register ******************************************************************/ case USRP2_CTRL_ID_POKE_THIS_REGISTER_FOR_ME_BRO: if (ctrl_data_in->data.poke_args.addr < 0xC000){ printf("error! tried to poke into 0x%x\n", ctrl_data_in->data.poke_args.addr); } else switch(ctrl_data_in->data.poke_args.num_bytes){ case sizeof(uint32_t): *((uint32_t *) ctrl_data_in->data.poke_args.addr) = (uint32_t)ctrl_data_in->data.poke_args.data; break; case sizeof(uint16_t): *((uint16_t *) ctrl_data_in->data.poke_args.addr) = (uint16_t)ctrl_data_in->data.poke_args.data; break; case sizeof(uint8_t): *((uint8_t *) ctrl_data_in->data.poke_args.addr) = (uint8_t)ctrl_data_in->data.poke_args.data; break; } ctrl_data_out.id = USRP2_CTRL_ID_OMG_POKED_REGISTER_SO_BAD_DUDE; break; case USRP2_CTRL_ID_PEEK_AT_THIS_REGISTER_FOR_ME_BRO: switch(ctrl_data_in->data.poke_args.num_bytes){ case sizeof(uint32_t): ctrl_data_in->data.poke_args.data = *((uint32_t *) ctrl_data_in->data.poke_args.addr); break; case sizeof(uint16_t): ctrl_data_in->data.poke_args.data = *((uint16_t *) ctrl_data_in->data.poke_args.addr); break; case sizeof(uint8_t): ctrl_data_in->data.poke_args.data = *((uint8_t *) ctrl_data_in->data.poke_args.addr); break; } ctrl_data_out.id = USRP2_CTRL_ID_WOAH_I_DEFINITELY_PEEKED_IT_DUDE; break; default: ctrl_data_out.id = USRP2_CTRL_ID_HUH_WHAT; } send_udp_pkt(USRP2_UDP_CTRL_PORT, src, &ctrl_data_out, sizeof(ctrl_data_out)); } /* * Called when an ethernet packet is received. * Return true if we handled it here, otherwise * it'll be passed on to the DSP Tx pipe */ static bool eth_pkt_inspector(dbsm_t *sm, int bufno) { //point me to the ethernet frame uint32_t *buff = (uint32_t *)buffer_ram(bufno); //treat this as fast-path data? // We have to do this operation as fast as possible. // Therefore, we do not check all the headers, // just check that the udp port matches // and that the vrt header is non zero. // In the future, a hardware state machine will do this... if ( //warning! magic numbers approaching.... (((buff + ((2 + 14 + 20)/sizeof(uint32_t)))[0] & 0xffff) == USRP2_UDP_DATA_PORT) && ((buff + ((2 + 14 + 20 + 8)/sizeof(uint32_t)))[0] != USRP2_INVALID_VRT_HEADER) ) return false; //test if its an ip recovery packet typedef struct{ padded_eth_hdr_t eth_hdr; char code[4]; union { struct ip_addr ip_addr; } data; }recovery_packet_t; recovery_packet_t *recovery_packet = (recovery_packet_t *)buff; if (recovery_packet->eth_hdr.ethertype == 0xbeee && strncmp(recovery_packet->code, "addr", 4) == 0){ printf("Got ip recovery packet: "); print_ip_addr(&recovery_packet->data.ip_addr); newline(); set_ip_addr(&recovery_packet->data.ip_addr); return true; } //pass it to the slow-path handler size_t len = buffer_pool_status->last_line[bufno] - 3; handle_eth_packet(buff, len); return true; } //------------------------------------------------------------------ static bool vrt_has_trailer(void){ return USRP2_HOST_RX_VRT_TRAILER_WORDS32 > 0; } static void setup_vrt(void){ // setup RX DSP regs sr_rx_ctrl->nsamples_per_pkt = streaming_items_per_frame; sr_rx_ctrl->nchannels = 1; sr_rx_ctrl->clear_overrun = 1; // reset sr_rx_ctrl->vrt_header = (0 | VRTH_PT_IF_DATA_WITH_SID | (vrt_has_trailer()? VRTH_HAS_TRAILER : 0) | VRTH_TSI_OTHER | VRTH_TSF_SAMPLE_CNT ); sr_rx_ctrl->vrt_stream_id = 0; sr_rx_ctrl->vrt_trailer = 0; } /* * 1's complement sum for IP and UDP headers * * init chksum to zero to start. */ static unsigned int CHKSUM(unsigned int x, unsigned int *chksum) { *chksum += x; *chksum = (*chksum & 0xffff) + (*chksum>>16); *chksum = (*chksum & 0xffff) + (*chksum>>16); return x; } /* * Called when eth phy state changes (w/ interrupts disabled) */ volatile bool link_is_up = false; // eth handler sets this void link_changed_callback(int speed) { link_is_up = speed != 0; hal_set_leds(link_is_up ? LED_RJ45 : 0x0, LED_RJ45); printf("\neth link changed: speed = %d\n", speed); } static void setup_network(void){ //setup ethernet header machine sr_udp_sm->eth_hdr.mac_dst_0_1 = (fp_mac_addr_dst.addr[0] << 8) | fp_mac_addr_dst.addr[1]; sr_udp_sm->eth_hdr.mac_dst_2_3 = (fp_mac_addr_dst.addr[2] << 8) | fp_mac_addr_dst.addr[3]; sr_udp_sm->eth_hdr.mac_dst_4_5 = (fp_mac_addr_dst.addr[4] << 8) | fp_mac_addr_dst.addr[5]; sr_udp_sm->eth_hdr.mac_src_0_1 = (fp_mac_addr_src.addr[0] << 8) | fp_mac_addr_src.addr[1]; sr_udp_sm->eth_hdr.mac_src_2_3 = (fp_mac_addr_src.addr[2] << 8) | fp_mac_addr_src.addr[3]; sr_udp_sm->eth_hdr.mac_src_4_5 = (fp_mac_addr_src.addr[4] << 8) | fp_mac_addr_src.addr[5]; sr_udp_sm->eth_hdr.ether_type = ETHERTYPE_IPV4; //setup ip header machine unsigned int chksum = 0; sr_udp_sm->ip_hdr.ver_ihl_tos = CHKSUM(0x4500, &chksum); // IPV4, 5 words of header (20 bytes), TOS=0 sr_udp_sm->ip_hdr.total_length = UDP_SM_INS_IP_LEN; // Don't checksum this line in SW sr_udp_sm->ip_hdr.identification = CHKSUM(0x0000, &chksum); // ID sr_udp_sm->ip_hdr.flags_frag_off = CHKSUM(0x4000, &chksum); // don't fragment sr_udp_sm->ip_hdr.ttl_proto = CHKSUM(0x2011, &chksum); // TTL=32, protocol = UDP (17 decimal) //sr_udp_sm->ip_hdr.checksum .... filled in below uint32_t src_ip_addr = fp_socket_src.addr.addr; uint32_t dst_ip_addr = fp_socket_dst.addr.addr; sr_udp_sm->ip_hdr.src_addr_high = CHKSUM(src_ip_addr >> 16, &chksum); // IP src high sr_udp_sm->ip_hdr.src_addr_low = CHKSUM(src_ip_addr & 0xffff, &chksum); // IP src low sr_udp_sm->ip_hdr.dst_addr_high = CHKSUM(dst_ip_addr >> 16, &chksum); // IP dst high sr_udp_sm->ip_hdr.dst_addr_low = CHKSUM(dst_ip_addr & 0xffff, &chksum); // IP dst low sr_udp_sm->ip_hdr.checksum = UDP_SM_INS_IP_HDR_CHKSUM | (chksum & 0xffff); //setup the udp header machine sr_udp_sm->udp_hdr.src_port = fp_socket_src.port; sr_udp_sm->udp_hdr.dst_port = fp_socket_dst.port; sr_udp_sm->udp_hdr.length = UDP_SM_INS_UDP_LEN; sr_udp_sm->udp_hdr.checksum = UDP_SM_LAST_WORD; // zero UDP checksum } /* * This is called when the DSP Rx chain has filled in a packet. */ bool fw_sets_seqno_inspector(dbsm_t *sm, int buf_this) // returns false { // insert the correct length into the control word and vrt header rx_dsp_buff_t *buff = (rx_dsp_buff_t*)buffer_ram(buf_this); size_t vrt_len = buffer_pool_status->last_line[buf_this]-1; buff->control_word = MK_RX_CTRL_WORD(vrt_len); buff->vrt_header[0] = (buff->vrt_header[0] & ~VRTH_PKT_SIZE_MASK) | (vrt_len & VRTH_PKT_SIZE_MASK); // queue up another rx command when required if (auto_reload_command && --streaming_frame_count == 0){ streaming_frame_count = FRAMES_PER_CMD; sr_rx_ctrl->time_secs = 0; sr_rx_ctrl->time_ticks = 0; //enqueue last command } return false; // we didn't handle the packet } inline static void buffer_irq_handler(unsigned irq) { uint32_t status = buffer_pool_status->status; dbsm_process_status(&dsp_tx_sm, status); dbsm_process_status(&dsp_rx_sm, status); } int main(void) { u2_init(); putstr("\nTxRx-NEWETH\n"); print_mac_addr(ethernet_mac_addr()->addr); newline(); print_ip_addr(get_ip_addr()); newline(); ethernet_register_link_changed_callback(link_changed_callback); ethernet_init(); register_mac_addr(ethernet_mac_addr()); register_ip_addr(get_ip_addr()); register_udp_listener(USRP2_UDP_CTRL_PORT, handle_udp_ctrl_packet); register_udp_listener(USRP2_UDP_DATA_PORT, handle_udp_data_packet); #if 0 // make bit 15 of Tx gpio's be a s/w output hal_gpio_set_sel(GPIO_TX_BANK, 15, 's'); hal_gpio_set_ddr(GPIO_TX_BANK, 0x8000, 0x8000); #endif //set them all to the atr settings by default hal_gpio_set_sels(GPIO_TX_BANK, "aaaaaaaaaaaaaaaa"); hal_gpio_set_sels(GPIO_RX_BANK, "aaaaaaaaaaaaaaaa"); output_regs->debug_mux_ctrl = 1; #if DEBUG_MODE hal_gpio_set_sels(GPIO_TX_BANK, "0000000000000000"); hal_gpio_set_sels(GPIO_RX_BANK, "0000000000000000"); hal_gpio_set_ddr(GPIO_TX_BANK, 0xffff, 0xffff); hal_gpio_set_ddr(GPIO_RX_BANK, 0xffff, 0xffff); #endif // initialize double buffering state machine for ethernet -> DSP Tx dbsm_init(&dsp_tx_sm, DSP_TX_BUF_0, &dsp_tx_recv_args, &dsp_tx_send_args, eth_pkt_inspector); // initialize double buffering state machine for DSP RX -> Ethernet dbsm_init(&dsp_rx_sm, DSP_RX_BUF_0, &dsp_rx_recv_args, &dsp_rx_send_args, fw_sets_seqno_inspector); // tell app_common that this dbsm could be sending to the ethernet ac_could_be_sending_to_eth = &dsp_rx_sm; sr_tx_ctrl->clear_state = 1; bp_clear_buf(DSP_TX_BUF_0); bp_clear_buf(DSP_TX_BUF_1); // kick off the state machine dbsm_start(&dsp_tx_sm); //int which = 0; while(1){ // hal_gpio_write(GPIO_TX_BANK, which, 0x8000); // which ^= 0x8000; buffer_irq_handler(0); int pending = pic_regs->pending; // poll for under or overrun if (pending & PIC_UNDERRUN_INT){ dbsm_handle_tx_underrun(&dsp_tx_sm); pic_regs->pending = PIC_UNDERRUN_INT; // clear interrupt putchar('U'); } if (pending & PIC_OVERRUN_INT){ dbsm_handle_rx_overrun(&dsp_rx_sm); pic_regs->pending = PIC_OVERRUN_INT; // clear pending interrupt // FIXME Figure out how to handle this robustly. // Any buffers that are emptying should be allowed to drain... if (auto_reload_command){ // restart_streaming(); // FIXME report error } else { // FIXME report error } putchar('O'); } } }