/// <summary>
/// Transforms a raw frame (i.e., byte sequence) into the abstraction we use for NetFPGA's data+metadata, and sets in the input port metadata to a specific port number.
/// </summary>
/// <param name="tdata_e">The raw frame data</param>
/// <param name="intfNumber">The 0-based port number the frame is arriving on</param>
/// <remarks>
/// Note that this involves copying the data (into a ulong array).
/// </remarks>
public static NetFPGA_Data CreateData(IEnumerable <byte> tdata_e, int intfNumber)
{
var d = new NetFPGA_Data();
var tdata_b = tdata_e.ToArray();
var length = (int)Math.Ceiling(tdata_b.Length / 8.0);
Buffer.BlockCopy(tdata_b, 0, d.tdata, 0, tdata_b.Length);
var tkeep = Enumerable.Repeat((byte)0xff, length - 1).Append((byte)~(~0 << tdata_b.Length % 8)).ToArray();
Array.Copy(tkeep, d.tkeep, tkeep.Length);
var tlast = Enumerable.Repeat(false, length - 1).Append(true).ToArray();
Array.Copy(tlast, d.tlast, tlast.Length);
var tuser_hi = Enumerable.Repeat(0uL, length).ToArray();
Array.Copy(tuser_hi, d.tuser_hi, tuser_hi.Length);
var tuser_low = Enumerable.Repeat(((1uL << (intfNumber * 2)) << 16) | (byte)tdata_b.Length, length).ToArray();
Array.Copy(tuser_low, d.tuser_low, tuser_low.Length);
return(d);
}
/// <summary>
/// Update the metadata to broadcast the frame (to all ports except the
/// one that the frame was received on).
/// </summary>
public static void Broadcast(ref NetFPGA_Data dataplane)
{
ulong broadcast_ports = ((dataplane.tuser_low[0] ^ NetFPGA_Data.default_oqs) >> 8) << 16 | dataplane.tuser_low[0];
dataplane.tuser_low[0] = (ulong)(broadcast_ports | dataplane.tuser_low[0]);
return;
}
/// <summary>
/// Set the output port to a specific value.
/// (i.e., the port to which we are forwarding the frame.)
/// </summary>
public static void Set_Output_Port(ref NetFPGA_Data dataplane, ulong value)
{
// FIXME we currently don't one-hot encode "value"
value = value << NetFPGA_Data.tuser_low_destination_port;
dataplane.tuser_low[0] = (ulong)(value | dataplane.tuser_low[0]);
return;
}
// Extract the frame from NetFPGA_Data into a byte array.
public static void Get_Frame(NetFPGA_Data src, ref byte[] dst)
{
// FIXME we don't check the bounds of dst.
// FIXME we don't null unused locations in dst.
int offset = 0;
for (int i = 0; i < src.tdata.Length; i++)
{
byte[] bs = BitConverter.GetBytes(src.tdata[i]);
for (int j = 0; j < bs.Length; j++)
{
if (src.tlast[i] && NetFPGA.to_keep(src, i) > j)
{
break;
}
dst[offset] = bs[j];
offset++;
}
if (src.tlast[i])
{
break;
}
}
}
/// <summary>
/// Read the output ports that are currently set in the metadata.
/// (i.e., the port(s) to which we are forwarding the frame.)
/// </summary>
public static byte Get_Output_Ports(ref NetFPGA_Data dataplane,
ref int[] output_ports, int?max_ports = null)
{
ulong value = dataplane.tuser_low[0];
value = (value >> NetFPGA_Data.tuser_low_destination_port);
bool nf0 = (value & 0x01L) > 0;
bool nf1 = (value & 0x04L) > 0;
bool nf2 = (value & 0x10L) > 0;
bool nf3 = (value & 0x40L) > 0;
// FIXME code in this function is a bit dirty -- can be tidied up?
byte dim = 0;
if (nf0)
{
dim++;
}
if (nf1 && max_ports.HasValue && max_ports.Value > 1)
{
dim++;
}
if (nf2 && max_ports.HasValue && max_ports.Value > 2)
{
dim++;
}
if (nf3 && max_ports.HasValue && max_ports.Value > 3)
{
dim++;
}
Debug.Assert(dim == output_ports.Length);
int i = 0;
if (nf0)
{
output_ports[i] = 0;
i++;
}
if (nf1)
{
output_ports[i] = 1;
i++;
}
if (nf2)
{
output_ports[i] = 2;
i++;
}
if (nf3)
{
output_ports[i] = 3;
i++;
}
return(dim);
}
// This method describes the operations required to rx a frame over the AXI4-Stream.
// and extract basic information such as dst_MAC, src_MAC, dst_port, src_port
protected static uint ReceiveFrame()
{
var frame = FrameController.ReceiveFrame();
dataplane = frame.Data;
uint size = (uint)Math.Min(dataplane.tdata.Length, dataplane.tlast.TakeWhile(x => !x).Count() + 1); // Length of frame in ulongs
return(size);
}
public static NetFPGA_Data DeepClone(this NetFPGA_Data src)
{
var r = new NetFPGA_Data();
Array.Copy(src.tdata, r.tdata, src.tdata.Length);
Array.Copy(src.tkeep, r.tkeep, src.tkeep.Length);
Array.Copy(src.tlast, r.tlast, src.tlast.Length);
Array.Copy(src.tuser_hi, r.tuser_hi, src.tuser_hi.Length);
Array.Copy(src.tuser_low, r.tuser_low, src.tuser_low.Length);
return(r);
}
/// <summary>
/// Send a frame. Uses the network interface specified by the supplied metadata.
/// </summary>
/// <param name="data">The data of the frame to send.</param>
public void SendFrame(NetFPGA_Data data)
{
// Use the current timestamp for this frame
var frame = new FrameInfo(data, sw.Elapsed);
// Notify listeners of frame being sent
OnSendFrame?.Invoke(this, new FrameEventArgs(frame, sw.Elapsed));
// Log that the frame was sent
_SentFrames.Add(frame);
}
/// <summary>
/// Converts the data (<see cref="NetFPGA_Data.tdata"/>) into a binary string, with a title,
/// and each ulong on a new line.
/// </summary>
public static string ToBinaryString(this NetFPGA_Data d)
{
StringBuilder sb = new StringBuilder();
sb.AppendLine("tdata:");
for (int i = 0; i < d.tdata.Length && !d.tlast[i]; i++)
{
sb.Append(" ");
sb.AppendLine(d.tdata[i].ToBinaryString());
}
return(sb.ToString());
}
/// <summary>
/// Converts the data (<see cref="NetFPGA_Data.tdata"/>) into a hex string, with a title,
/// and each ulong on a new line.
/// </summary>
public static string ToHexString(this NetFPGA_Data d)
{
StringBuilder sb = new StringBuilder();
sb.AppendLine("tdata:");
for (int i = 0; i < d.tdata.Length; i++)
{
sb.Append(" ");
sb.AppendLine(d.tdata[i].ToString("X16"));
if (d.tlast[i])
{
break;
}
}
return(sb.ToString());
}
public static void Write48(this NetFPGA_Data dataplane, ulong v, int offset)
{
int index64 = offset / 8;
int offset1 = offset % 8 * 8;
ulong data1 = v << offset1;
ulong mask1 = ~(0x0000FFFFFFFFFFFFuL << offset1);
dataplane.tdata[index64] = (dataplane.tdata[index64] & mask1) | data1;
index64++;
offset1 = 64 - offset1;
ulong data2 = offset1 >= 64 ? 0 : v >> offset1;
ulong mask2 = offset1 >= 64 ? ~0uL : ~(0x0000FFFFFFFFFFFFuL >> offset1);
dataplane.tdata[index64] = (dataplane.tdata[index64] & mask2) | data2;
}
// Move the contents of a byte array into the frame field in NetFPGA_Data.
public static void Set_Frame(byte[] src, ref NetFPGA_Data dst)
{
// If not ulong (8-byte) aligned then we indicate this using
// NetFPGA_Data.tkeep. We indicate the end of the frame by setting
// NetFPGA_Data.tlast.
int i = 0;
int max = dst.tdata.Length / sizeof(ulong);
byte[] buf = new byte[sizeof(long)];
for (i = 0; i < max; i++)
{
for (int j = 0; j < sizeof(long); j++)
{
buf[j] = src[i + j];
}
dst.tdata[i * sizeof(long)] = BitConverter.ToUInt32(buf, 0);
dst.tlast[i] = false;
}
// Now we handle the last word.
dst.tlast[i] = true;
byte to_keep = (byte)(dst.tdata.Length % sizeof(ulong));
dst.tkeep[i] = one_hot_encode(to_keep);
// Copy remaining bytes.
int k = 0;
for (k = 0; k < to_keep; k++)
{
buf[k] = src[i + k];
}
// Zero-out the bytes until the word boundary.
for (; k < sizeof(ulong); k++)
{
buf[k] = 0;
}
dst.tdata[i * sizeof(long)] = BitConverter.ToUInt32(buf, 0);
}
/// <summary>
/// Read the input port (i.e., port on which we received the frame).
/// </summary>
public static uint Read_Input_Port(NetFPGA_Data dataplane)
{
uint encoded_in_port = (uint)(dataplane.tuser_low[0] >> NetFPGA_Data.tuser_low_source_port);
encoded_in_port &= 0x00FF; // Zero out the destination port.
uint in_port = 0;
while ((encoded_in_port & 1) == 0)
{
in_port++;
encoded_in_port = encoded_in_port >> 2;
}
// "in_port" indicates network port index, starting with 0.
Debug.Assert(in_port < NetFPGA_Data.NET_PORTS);
return(in_port);
}
// Extract how many bytes we are keeping from a given (8 byte) segment as
// identified by an offset.
// This involves looking up the tkeep[offset] value and carrying out
// the one-hot decoding.
// NOTE we expect that the bits indicating which bits to keep are
// contiguous. We currently don't check this.
public static int to_keep(NetFPGA_Data src, int offset)
{
byte tkeep = src.tkeep[offset];
int keeping = 0;
const int bits_in_a_byte = 8;
for (int i = 0; i < bits_in_a_byte; i++)
{
tkeep = (byte)(tkeep >> i);
if ((tkeep & 0x1) == 1)
{
keeping++;
}
else
{
break;
}
}
return(keeping);
}
/// <summary>
/// Set the input port (i.e., port on which we received the frame).
/// </summary>
public static void Set_Input_Port(ref NetFPGA_Data dataplane, ulong value)
{
// "value" indicates network port index, starting with 0.
Debug.Assert(value < NetFPGA_Data.NET_PORTS);
// Map value into a bit-based encoding as described for source/destination
// ports in NetFPGA_Data.
ulong encoded_in_port = 1;
for (int i = (int)value; i > 0; i--)
{
encoded_in_port = encoded_in_port << 2;
}
// Move into position, in preparation for OR-ing.
encoded_in_port = encoded_in_port << NetFPGA_Data.tuser_low_source_port;
// Erase any existing input port.
dataplane.tuser_low[0] = (ulong)(0xFF00FFFF & dataplane.tuser_low[0]);
// Write the new input port.
dataplane.tuser_low[0] = (ulong)(encoded_in_port | dataplane.tuser_low[0]);
}
public FrameInfo(NetFPGA_Data data, TimeSpan time)
{
Data = data;
Time = time;
}
abstract public void Set_Data(NetFPGA_Data data);
