fix(w5100): revert buffer base to 0x4000/0x6000 — IDM decodes only 15 bits

Reverts the 0x8000/0xC000 change from 162dbf7, which was WRONG and actively broke transmission. The W5100S datasheet pseudo-code quotes 0x8000 (TX) / 0xC000 (RX) for the memory blocks, but the PARALLEL/indirect (IDM) interface only decodes a 15-bit offset. Bench-proven with an address-aliasing probe: writing distinct values to each candidate base and reading them back showed 0xC000 and 0x4000 are the SAME cell (0xC000 & 0x7FFF == 0x4000) while 0x6000 holds its own value. Consequence of the bad base: every payload byte written to 0x9800+i aliased down onto 0x0000+i, landing on SHAR (0x09-0x0E) and SIPR (0x0F-0x12) and overwriting them with the payload. The chip then transmitted frames with a garbage source MAC/IP, which the peer NIC drops without counting -- the "SEND_OK but rx_packets=0" symptom, and the bogus SIPR0 readback (0x50 was literally payload byte 15, 'P'). The NETLCKR unlock from 9c4bc7a is a genuine W5100S requirement and stays. Also: - w5100_udptest.py: self-contained configure+send+readback probe (and the address-aliasing probe that found this), reports over UART. - scripts/build-flash.sh: sweep N seeds and flash the best (capture timing is seed-dependent, so the sweep is mandatory). - scripts/uart-console.py: interactive UART console, plus --send/--read one-shot modes for scripting. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
2026-09-20 18:56:38 +00:00
parent 5d9880f9c5
commit 394b677c8f
5 changed files with 434 additions and 12 deletions
@@ -0,0 +1,50 @@
+#!/usr/bin/env bash
+# Build the current gateware over N nextpnr seeds and flash the best result.
+#
+# The capture domain (54 MHz) is routing-dominated and only closes on a minority
+# of seeds, so a sweep is mandatory — see CLAUDE.md.  synth.py ranks the seeds by
+# capture_clk fmax and reports the winner; this flashes that one.
+#
+#   ./scripts/build-flash.sh            # 8 seeds (default), build + flash
+#   ./scripts/build-flash.sh 12         # 12 seeds
+#   ./scripts/build-flash.sh 8 --no-flash   # build only, don't touch the board
+#
+# The socket-3 UDP bring-up test identity is set from these env vars (override
+# to match your LAN before running):
+#   UDP_SRC_IP UDP_SUBNET UDP_GATEWAY UDP_DST_IP UDP_SRC_PORT UDP_DST_PORT UDP_SOCKET
+set -euo pipefail
+cd "$(dirname "$0")/.."
+
+SEEDS="${1:-8}"
+NOFLASH="${2:-}"
+
+export UDP_SRC_IP="${UDP_SRC_IP:-192.168.2.99}"
+export UDP_SUBNET="${UDP_SUBNET:-255.255.255.0}"
+export UDP_GATEWAY="${UDP_GATEWAY:-192.168.2.1}"
+export UDP_DST_IP="${UDP_DST_IP:-192.168.2.112}"
+export UDP_SRC_PORT="${UDP_SRC_PORT:-40000}"
+export UDP_DST_PORT="${UDP_DST_PORT:-6464}"
+export UDP_SOCKET="${UDP_SOCKET:-3}"
+
+LOG="$(mktemp -t bbabuild.XXXXXX.log)"
+echo "==> building $SEEDS seeds (log: $LOG)"
+echo "    UDP: ${UDP_SRC_IP}:${UDP_SRC_PORT} -> ${UDP_DST_IP}:${UDP_DST_PORT} (socket ${UDP_SOCKET})"
+
+python -m exi_bba.synth --seeds "$SEEDS" 2>&1 | tee "$LOG"
+
+# synth.py prints:  "Bitstream for best seed: build/seedN/top.bin"
+BIN="$(grep -aoE 'build/seed[0-9]+/top\.bin' "$LOG" | tail -1 || true)"
+if [ -z "$BIN" ] || [ ! -f "$BIN" ]; then
+    echo "!! no best-seed bitstream found — check the log above" >&2
+    exit 1
+fi
+grep -aE 'Best seed' "$LOG" | tail -1 || true
+
+if [ "$NOFLASH" = "--no-flash" ]; then
+    echo "==> built $BIN (not flashing, --no-flash given)"
+    exit 0
+fi
+
+echo "==> flashing $BIN"
+iceprog "$BIN" 2>&1 | grep -aE 'VERIFY|cdone|Error|error|Bye' || true
+echo "==> done"
@@ -0,0 +1,102 @@
+#!/usr/bin/env python3
+"""Interactive UART console to the re-bba-rb board (FT2232H channel B).
+
+The BBA default build runs an interactive shell on this port ("rebbarb> "):
+    help                      list commands
+    udp broadcast [msg]       send a UDP broadcast on the test socket
+    udp unicast <ip> [msg]    send a UDP datagram to <ip>
+
+The bring-up diagnostics (w5100_selftest / w5100_udptest / w5100_regdump) just
+stream a status line on the same port, so this works for those too.
+
+Usage:
+    sudo ./scripts/uart-console.py                 # /dev/ttyUSB1 @ 115200
+    sudo ./scripts/uart-console.py /dev/ttyUSB0 115200
+    ./scripts/uart-console.py --send "udp broadcast hi"   # one-shot, no tty
+    ./scripts/uart-console.py --read 5                    # just dump 5s of output
+
+Channel A of the FT2232H is the MPSSE/iceprog port; the UART is channel B, which
+is normally the SECOND ttyUSB (…USB1).  Needs read/write on the device node —
+run under sudo, or add yourself to the port's group.
+
+Quit the interactive console with Ctrl-] (or Ctrl-C).
+"""
+import sys, time, argparse
+
+try:
+    import serial
+except ImportError:
+    sys.exit("needs pyserial:  pip install pyserial")
+
+
+def main():
+    ap = argparse.ArgumentParser(add_help=True)
+    ap.add_argument("port", nargs="?", default="/dev/ttyUSB1")
+    ap.add_argument("baud", nargs="?", type=int, default=115200)
+    ap.add_argument("--send", metavar="CMD",
+                    help="send one command, print the reply, exit")
+    ap.add_argument("--read", metavar="SECONDS", type=float,
+                    help="just read for N seconds and exit (no tty needed)")
+    args = ap.parse_args()
+
+    try:
+        ser = serial.Serial(args.port, args.baud, timeout=0.1)
+    except serial.SerialException as e:
+        sys.exit(f"cannot open {args.port}: {e}\n(try: sudo {' '.join(sys.argv)})")
+
+    # ── one-shot modes (safe in scripts / no controlling terminal) ───────────
+    if args.read is not None:
+        end = time.time() + args.read
+        while time.time() < end:
+            data = ser.read(256)
+            if data:
+                sys.stdout.write(data.decode("ascii", "replace"))
+                sys.stdout.flush()
+        return
+
+    if args.send is not None:
+        time.sleep(0.2); ser.reset_input_buffer()
+        ser.write(args.send.encode() + b"\r")
+        end = time.time() + 2.0
+        buf = b""
+        while time.time() < end:
+            buf += ser.read(256)
+        sys.stdout.write(buf.decode("ascii", "replace"))
+        return
+
+    # ── interactive console ─────────────────────────────────────────────────
+    import termios, tty, select
+    print(f"[uart-console] {args.port} @ {args.baud} 8N1 — Ctrl-] to quit\r")
+    fd = sys.stdin.fileno()
+    try:
+        old = termios.tcgetattr(fd)
+    except termios.error:
+        old = None
+    try:
+        if old is not None:
+            tty.setraw(fd)
+        while True:
+            r, _, _ = select.select([sys.stdin, ser], [], [], 0.05)
+            if ser in r:
+                data = ser.read(4096)
+                if data:
+                    sys.stdout.write(data.decode("ascii", "replace"))
+                    sys.stdout.flush()
+            if sys.stdin in r:
+                ch = sys.stdin.buffer.read(1)
+                if not ch or ch == b"\x1d":        # Ctrl-]
+                    break
+                if ch == b"\n":                     # send CR, the shell wants it
+                    ch = b"\r"
+                ser.write(ch)
+    except KeyboardInterrupt:
+        pass
+    finally:
+        if old is not None:
+            termios.tcsetattr(fd, termios.TCSADRAIN, old)
+        ser.close()
+        print("\r\n[uart-console] closed")
+
+
+if __name__ == "__main__":
+    main()