From bd90b7168354e025d55724c91119ab34b5370647 Mon Sep 17 00:00:00 2001
From: Martin Teichmann <martin.teichmann@xfel.eu>
Date: Tue, 2 Jan 2024 11:16:31 +0000
Subject: [PATCH] use enums for the state machine states
---
ebpfcat/ebpfcat.py | 5 ++--
ebpfcat/ethercat.py | 65 +++++++++++++++++++++++++--------------------
ebpfcat/scripts.py | 8 +++---
3 files changed, 43 insertions(+), 35 deletions(-)
diff --git a/ebpfcat/ebpfcat.py b/ebpfcat/ebpfcat.py
index 015d19b..e77a346 100644
--- a/ebpfcat/ebpfcat.py
+++ b/ebpfcat/ebpfcat.py
@@ -27,7 +27,8 @@ from struct import pack, unpack, calcsize, pack_into, unpack_from
from time import time
from .arraymap import ArrayMap, ArrayGlobalVarDesc
from .ethercat import (
- ECCmd, EtherCat, Packet, Terminal, EtherCatError, SyncManager)
+ ECCmd, EtherCat, MachineState, Packet, Terminal, EtherCatError,
+ SyncManager)
from .ebpf import FuncId, MemoryDesc, SubProgram, prandom
from .xdp import XDP, XDPExitCode, PacketVar as XDPPacketVar
from .bpf import (
@@ -250,7 +251,7 @@ class EBPFTerminal(Terminal):
(self.vendorId, self.productCode) not in self.compatibility):
raise EtherCatError(
f"Incompatible Terminal: {self.vendorId}:{self.productCode}")
- await self.to_operational(2)
+ await self.to_operational(MachineState.PRE_OPERATIONAL)
self.pdos = {}
outbits, inbits = await self.parse_pdos()
self.pdo_out_sz = int((outbits + 7) // 8)
diff --git a/ebpfcat/ethercat.py b/ebpfcat/ethercat.py
index ad8d39d..397cd56 100644
--- a/ebpfcat/ethercat.py
+++ b/ebpfcat/ethercat.py
@@ -135,6 +135,19 @@ class EEPROM(IntEnum):
REVISION = 12
SERIAL_NO = 14
+class MachineState(Enum):
+ """The states of the EtherCAT state machine
+
+ The states are in the order in which they should
+ be taken, BOOTSTRAP is at the end as this is a
+ state we usually do not go to.
+ """
+ INIT = 1
+ PRE_OPERATIONAL = 2
+ SAFE_OPERATIONAL = 4
+ OPERATIONAL = 8
+ BOOTSTRAP = 3
+
class SyncManager(Enum):
OUT = 2
IN = 3
@@ -561,43 +574,37 @@ class Terminal:
return ret
async def get_state(self):
- """get the current state and error flags"""
- state, error = await self.ec.roundtrip(ECCmd.FPRD, self.position,
- 0x0130, "H2xH")
- return state, error
+ """get the current state, error flag and status word"""
+ state, status = await self.ec.roundtrip(ECCmd.FPRD, self.position,
+ 0x0130, "H2xH")
+ return MachineState(state & 0xf), bool(state & 0x10), status
- async def to_operational(self, target=8):
+ async def to_operational(self, target=MachineState.OPERATIONAL):
"""try to bring the terminal to operational state
this tries to push the terminal through its state machine to the
- operational state. Note that even if it reaches there, the terminal
+ target state. Note that even if it reaches there, the terminal
will quickly return to pre-operational if no packets are sent to keep
- it operational. """
- order = [1, 2, 4, 8]
- ret, error = await self.ec.roundtrip(
- ECCmd.FPRD, self.position, 0x0130, "H2xH")
- if ret & 0x10:
+ it operational.
+
+ return the state, error flag and status before the operation."""
+ order = list(MachineState)
+ state, error, status = ret = await self.get_state()
+ if error:
await self.ec.roundtrip(ECCmd.FPWR, self.position,
0x0120, "H", 0x11)
- ret, error = await self.ec.roundtrip(ECCmd.FPRD, self.position,
- 0x0130, "H2xH")
- pos = order.index(ret)
- s = 0x11
- for state in order[pos+1:]:
+ state = MachineState.INIT
+ pos = order.index(state) + 1
+ state = None
+ for current in order[pos:]:
await self.ec.roundtrip(ECCmd.FPWR, self.position,
- 0x0120, "H", state)
- while s != state:
- s, error = await self.ec.roundtrip(ECCmd.FPRD, self.position,
- 0x0130, "H2xH")
- if error != 0:
- raise EtherCatError(f"AL register {error}")
- if state >= target:
- return
-
- async def get_error(self):
- """read the error register"""
- return (await self.ec.roundtrip(ECCmd.FPRD, self.position,
- 0x0134, "H"))[0]
+ 0x0120, "H", current.value)
+ while current is not state:
+ state, error, status = await self.get_state()
+ if error:
+ raise EtherCatError(f"AL register error {status}")
+ if state.value >= target.value:
+ return ret
async def read(self, start, *args, **kwargs):
"""read data from the terminal at offset `start`
diff --git a/ebpfcat/scripts.py b/ebpfcat/scripts.py
index 7b2de85..0dd6d50 100644
--- a/ebpfcat/scripts.py
+++ b/ebpfcat/scripts.py
@@ -6,7 +6,7 @@ from pprint import PrettyPrinter
from struct import unpack
import sys
-from .ethercat import EtherCat, Terminal, ECCmd, EtherCatError
+from .ethercat import EtherCat, MachineState, Terminal, ECCmd, EtherCatError
def entrypoint(func):
@wraps(func)
@@ -73,7 +73,7 @@ async def info():
print(f"{k:2}: {v}\n {v.hex()}")
if args.sdo:
- await t.to_operational(2)
+ await t.to_operational(MachineState.PRE_OPERATIONAL)
ret = await t.read_ODlist()
for k, v in ret.items():
print(f"{k:X}:")
@@ -91,7 +91,7 @@ async def info():
print(f" {r}")
print(f" {r!r}")
if args.pdo:
- await t.to_operational(2)
+ await t.to_operational(MachineState.PRE_OPERATIONAL)
await t.parse_pdos()
for (idx, subidx), (sm, pos, fmt) in t.pdos.items():
print(f"{idx:4X}:{subidx:02X} {sm} {pos} {fmt}")
@@ -168,7 +168,7 @@ async def create_test():
await t.initialize(-i, await ec.find_free_address())
sdo = {}
if t.has_mailbox():
- await t.to_operational(2)
+ await t.to_operational(MachineState.PRE_OPERATIONAL)
odlist = await t.read_ODlist()
for k, v in odlist.items():
--
GitLab