diff options
Diffstat (limited to 'firmware/zpu/apps/bitrot/tx_drop.c')
| -rw-r--r-- | firmware/zpu/apps/bitrot/tx_drop.c | 261 |
1 files changed, 261 insertions, 0 deletions
diff --git a/firmware/zpu/apps/bitrot/tx_drop.c b/firmware/zpu/apps/bitrot/tx_drop.c new file mode 100644 index 000000000..3a336e938 --- /dev/null +++ b/firmware/zpu/apps/bitrot/tx_drop.c @@ -0,0 +1,261 @@ +/* + * 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 <http://www.gnu.org/licenses/>. + */ + +#ifdef HAVE_CONFIG_H +#include "config.h" +#endif + +#include "u2_init.h" +#include "memory_map.h" +#include "spi.h" +#include "hal_io.h" +#include "buffer_pool.h" +#include "pic.h" +#include <stdbool.h> +#include "ethernet.h" +#include "nonstdio.h" +#include "usrp2_eth_packet.h" +#include "dbsm.h" +#include "app_common.h" +#include "print_rmon_regs.h" +#include <stddef.h> +#include <stdlib.h> +#include <string.h> + + +/* + * Like tx_only.c, but we discard data packets instead of sending them to the + * DSP TX pipeline. + */ + +int total_rx_pkts = 0; +int total_rx_bytes = 0; + + +static int timer_delta = MASTER_CLK_RATE/1000; // tick at 1kHz + +/* + * This program can respond to queries from the host + * and stream rx samples. + * + * 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 CPU_TX_BUF 1 // cpu -> eth + +#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 + * ================================================================ + */ + +// 4 lines of ethernet hdr + 2 lines (word0 + timestamp) +// DSP Tx reads word0 (flags) + timestamp followed by samples + +#define DSP_TX_FIRST_LINE 4 +#define DSP_TX_SAMPLES_PER_FRAME 250 // not used except w/ debugging +#define DSP_TX_EXTRA_LINES 2 // reads word0 + timestamp + +// 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 ethernet header + 0 // filled in from last_line register +}; + +dbsm_t dsp_tx_sm; // the state machine + + +// ---------------------------------------------------------------- + + +// The mac address of the host we're sending to. +eth_mac_addr_t host_mac_addr; + + +void +timer_irq_handler(unsigned irq) +{ + hal_set_timeout(timer_delta); // schedule next timeout +} + +// Tx DSP underrun +void +underrun_irq_handler(unsigned irq) +{ + putchar('U'); + + dbsm_stop(&dsp_tx_sm); + dsp_tx_regs->clear_state = 1; + dbsm_start(&dsp_tx_sm); // restart sm so we're listening to ethernet again + + // putstr("\nirq: underrun\n"); +} + + +void +start_rx_cmd(const eth_mac_addr_t *host, op_start_rx_t *p) +{ +} + +void +stop_rx_cmd(void) +{ +} + +static void +setup_tx() +{ + dsp_tx_regs->clear_state = 1; + bp_clear_buf(DSP_TX_BUF_0); + bp_clear_buf(DSP_TX_BUF_1); + + int tx_scale = 256; + int interp = 32; + + op_config_tx_t def_config; + memset(&def_config, 0, sizeof(def_config)); + def_config.phase_inc = 408021893; // 9.5 MHz [2**32 * fc/fsample] + def_config.scale_iq = (tx_scale << 16) | tx_scale; + def_config.interp = interp; + + // setup Tx DSP regs + config_tx_cmd(&def_config); +} + + +inline static void +buffer_irq_handler(unsigned irq) +{ + uint32_t status = buffer_pool_status->status; + + if (status & BPS_ERROR_ALL){ + // FIXME rare path, handle error conditions + putstr("Errors! status = "); + puthex32_nl(status); + + printf("total_rx_pkts = %d\n", total_rx_pkts); + printf("total_rx_bytes = %d\n", total_rx_bytes); + + print_rmon_regs(); + + if (status & (BPS_ERROR(DSP_TX_BUF_0) | BPS_ERROR(DSP_TX_BUF_1))){ + dbsm_stop(&dsp_tx_sm); + dsp_tx_regs->clear_state = 1; // try to restart + dbsm_start(&dsp_tx_sm); + return; + } + } + + dbsm_process_status(&dsp_tx_sm, status); + + if (status & BPS_DONE(CPU_TX_BUF)){ + bp_clear_buf(CPU_TX_BUF); + } +} + + +/* + * Called when an ethernet packet is received. + * + * Claim that we handled all the packets, + * dropping those destined for the TX DSP chain + * on the ground. + */ +bool +nop_eth_pkt_inspector(dbsm_t *sm, int bufno) +{ + hal_toggle_leds(0x1); + + u2_eth_packet_t *pkt = (u2_eth_packet_t *) buffer_ram(bufno); + size_t byte_len = (buffer_pool_status->last_line[bufno] - 1) * 4; + + total_rx_pkts++; + total_rx_bytes += byte_len; + + // inspect rcvd frame and figure out what do do. + + if (pkt->ehdr.ethertype != U2_ETHERTYPE) + return true; // ignore, probably bogus PAUSE frame from MAC + + int chan = u2p_chan(&pkt->fixed); + + switch (chan){ + case CONTROL_CHAN: + handle_control_chan_frame(pkt, byte_len); + return true; // we handled the packet + break; + + case 0: + default: + return true; // We handled the data by dropping it :) + break; + } +} + + +int +main(void) +{ + u2_init(); + + // setup tx gpio bits for GPIOM_FPGA_1 -- fpga debug output + hal_gpio_set_tx_mode(15, 0, GPIOM_FPGA_1); + hal_gpio_set_rx_mode(15, 0, GPIOM_FPGA_1); + + putstr("\ntx_drop\n"); + + // Control LEDs + hal_set_leds(0x0, 0x3); + + pic_register_handler(IRQ_UNDERRUN, underrun_irq_handler); + + ethernet_register_link_changed_callback(link_changed_callback); + ethernet_init(); + + // 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, + nop_eth_pkt_inspector); + + // program tx registers + setup_tx(); + + // kick off the state machine + dbsm_start(&dsp_tx_sm); + + while(1){ + buffer_irq_handler(0); + } +} + |