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drtio: add rt_packets TX datapath, fixes

This commit is contained in:
Sebastien Bourdeauducq 2016-10-07 15:35:29 +08:00
parent 76bac21d14
commit cb0d1549c6
1 changed files with 108 additions and 15 deletions

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@ -1,15 +1,24 @@
from types import SimpleNamespace
from migen import *
from migen.genlib.fsm import *
from migen.genlib.record import *
def layout_len(l):
return sum(e[1] for e in l)
class PacketLayoutManager:
def __init__(self, alignment):
self.alignment = alignment
self.layouts = dict()
self.types = dict()
self.type_names = dict()
def add_type(self, name, *fields, pad=True):
self.types[name] = len(self.types)
type_n = len(self.types)
self.types[name] = type_n
self.type_names[type_n] = name
layout = [("ty", 8)] + list(fields)
misalignment = layout_len(layout) % self.alignment
if misalignment:
@ -32,11 +41,18 @@ def get_m2s_layouts(alignment):
def get_s2m_layouts(alignment):
plm = PacketLayoutManager(alignment)
plm.add_type("error", ("code", 8))
plm.add_type("echo_reply")
plm.add_type("fifo_level_reply", ("level", 24))
return plm
error_codes = {
"frame_missed": 0,
"unknown_type": 1
}
class ReceiveDatapath(Module):
def __init__(self, ws, plm):
# inputs
@ -56,8 +72,8 @@ class ReceiveDatapath(Module):
# # #
# input pipeline stage - determine packet length based on type
lastword_per_type = [layout_len(l)//ws - 1
for l in plm.layouts.values()]
lastword_per_type = [layout_len(plm.layouts[plm.type_names[i]])//ws - 1
for i in range(len(plm.layouts))]
packet_last_n = Signal(max=max(lastword_per_type)+1)
self.sync += [
self.frame_r.eq(self.frame),
@ -84,10 +100,73 @@ class ReceiveDatapath(Module):
)
self.comb += self.packet_last.eq(packet_buffer_count == packet_last_n)
# cast packet
# dissect packet
for name, layout in plm.layouts.items():
self.packet_as[name] = Record(layout)
self.comb += self.packet_as[name].raw_bits().eq(packet_buffer)
fields = SimpleNamespace()
idx = 0
for field_name, field_size in layout:
setattr(fields, field_name, packet_buffer[idx:idx+field_size])
idx += field_size
self.packet_as[name] = fields
class TransmitDatapath(Module):
def __init__(self, ws, plm):
self.ws = ws
self.plm = plm
# inputs
self.packet_buffer = Signal(max(layout_len(l)
for l in plm.layouts.values()))
w_in_packet = len(self.packet_buffer)//ws
self.packet_len = Signal(max=w_in_packet+1)
# control
self.stb = Signal()
self.done = Signal()
# outputs
self.frame = Signal()
self.data = Signal(ws)
# # #
packet_buffer_count = Signal(max=w_in_packet+1)
self.sync += [
self.done.eq(0),
self.frame.eq(0),
packet_buffer_count.eq(0),
If(self.stb & ~self.done,
If(packet_buffer_count == self.packet_len,
self.done.eq(1)
).Else(
self.frame.eq(1),
Case(packet_buffer_count,
{i: self.data.eq(self.packet_buffer[i*ws:(i+1)*ws])
for i in range(w_in_packet)}),
packet_buffer_count.eq(packet_buffer_count + 1)
)
)
]
def send(self, ty, **kwargs):
idx = 8
value = self.plm.types[ty]
for field_name, field_size in self.plm.layouts[ty][1:]:
try:
fvalue = kwargs[field_name]
del kwargs[field_name]
except KeyError:
fvalue = 0
value = value | (fvalue << idx)
idx += field_size
if kwargs:
raise ValueError
return [
self.packet_buffer.eq(value),
self.packet_len.eq(idx//self.ws)
]
class RTPacketSatellite(Module):
@ -109,7 +188,15 @@ class RTPacketSatellite(Module):
rx_dp.data.eq(self.rx_rt_data)
]
fsm = FSM(reset_state="WAIT_FRAME")
tx_plm = get_s2m_layouts(ws)
tx_dp = TransmitDatapath(ws, tx_plm)
self.submodules += tx_dp
self.comb += [
self.tx_rt_frame.eq(tx_dp.frame),
self.tx_rt_data.eq(tx_dp.data)
]
fsm = FSM(reset_state="WAIT_INPUT")
self.submodules += fsm
continuation = Signal()
@ -123,7 +210,7 @@ class RTPacketSatellite(Module):
If(rx_dp.frame_r,
If(~frame_r_r | continuation_r,
continuation.eq(1),
packet_buffer_load.eq(1),
rx_dp.packet_buffer_load.eq(1),
If(rx_dp.packet_last,
Case(rx_dp.packet_type, {
rx_plm.types["echo_request"]: NextState("ECHO"),
@ -135,12 +222,18 @@ class RTPacketSatellite(Module):
)
)
)
fsm.state("ECHO",
NextState("WAIT_INPUT")
fsm.act("ECHO",
tx_dp.send("echo_reply"),
tx_dp.stb.eq(1),
If(tx_dp.done, NextState("WAIT_INPUT"))
)
fsm.state("ERROR_FRAME_MISSED",
NextState("WAIT_INPUT")
fsm.act("ERROR_FRAME_MISSED",
tx_dp.send("error", code=error_codes["frame_missed"]),
tx_dp.stb.eq(1),
If(tx_dp.done, NextState("WAIT_INPUT"))
)
fsm.state("ERROR_UNKNOWN_TYPE",
NextState("WAIT_INPUT")
fsm.act("ERROR_UNKNOWN_TYPE",
tx_dp.send("error", code=error_codes["unknown_type"]),
tx_dp.stb.eq(1),
If(tx_dp.done, NextState("WAIT_INPUT"))
)