1 files changed, 233 insertions, 0 deletions
diff --git a/firmware/microblaze/apps/bitrot/tx_drop_rate_limited.c b/firmware/microblaze/apps/bitrot/tx_drop_rate_limited.c
new file mode 100644
index 000000000..2b8db7f7d
--- /dev/null
+++ b/firmware/microblaze/apps/bitrot/tx_drop_rate_limited.c
@@ -0,0 +1,233 @@
+/*
+ * 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 "eth_mac.h"
+#include <stddef.h>
+#include <stdlib.h>
+#include <string.h>
+
+
+/*
+ * receive packets from ethernet at a fixed rate and discard them
+ */
+
+int total_rx_pkts = 0;
+int total_rx_bytes = 0;
+
+
+static int timer_delta = (int)(MASTER_CLK_RATE * 10e-6); // 10us / tick
+
+
+/*
+ * 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
+
+
+
+// ----------------------------------------------------------------
+
+
+// The mac address of the host we're sending to.
+eth_mac_addr_t host_mac_addr;
+
+
+static volatile bool receive_packet_now = false;
+
+void
+timer_irq_handler(unsigned irq)
+{
+  hal_set_timeout(timer_delta);	// schedule next timeout
+  receive_packet_now = true;
+}
+
+
+// Tx DSP underrun
+void
+underrun_irq_handler(unsigned irq)
+{
+  putchar('U');
+}
+
+
+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);
+}
+
+
+/*
+ * 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;
+  }
+}
+
+
+inline static void
+buffer_irq_handler(unsigned irq)
+{
+  uint32_t  status = buffer_pool_status->status;
+
+  if (status & (BPS_DONE(CPU_TX_BUF) | BPS_ERROR(CPU_TX_BUF)))
+    bp_clear_buf(CPU_TX_BUF);
+
+  if (status & (BPS_DONE(DSP_TX_BUF_0) | BPS_ERROR(DSP_TX_BUF_0))){
+    bp_clear_buf(DSP_TX_BUF_0);
+
+    if (status & BPS_ERROR(DSP_TX_BUF_0)){
+      int crc = eth_mac_read_rmon(0x05);
+      int fifo_full = eth_mac_read_rmon(0x06);
+      int too_short_too_long = eth_mac_read_rmon(0x07);
+      putstr("Errors! status = ");
+      puthex32_nl(status);
+
+      printf("crc_err\t\t= %d\n", crc);
+      printf("fifo_full\t\t= %d\n", fifo_full);
+      printf("too_short_too_long\t= %d\n", too_short_too_long);
+
+      printf("total_rx_pkts  = %d\n", total_rx_pkts);
+      printf("total_rx_bytes = %d\n", total_rx_bytes);
+    }
+    else
+      nop_eth_pkt_inspector(0, DSP_TX_BUF_0);
+  }
+
+  if (receive_packet_now && (status & BPS_IDLE(DSP_TX_BUF_0))){
+    receive_packet_now = false;
+    bp_receive_to_buf(DSP_TX_BUF_0, PORT_ETH, 1, 0, BP_LAST_LINE);
+  }
+}
+
+
+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_rate_limited\n");
+  
+  // Control LEDs
+  hal_set_leds(0x0, 0x3);
+
+  pic_register_handler(IRQ_UNDERRUN, underrun_irq_handler);
+
+  pic_register_handler(IRQ_TIMER, timer_irq_handler);
+  hal_set_timeout(timer_delta);
+
+  ethernet_register_link_changed_callback(link_changed_callback);
+  ethernet_init();
+
+  // program tx registers
+  setup_tx();
+
+  // start a receive from ethernet
+  bp_receive_to_buf(DSP_TX_BUF_0, PORT_ETH, 1, 0, BP_LAST_LINE);
+
+  while(1){
+    buffer_irq_handler(0);
+  }
+}
+