hv/trace_cd3217: Add tracing for TI/Apple cd3217 USB type C controller

Interface (as used by macOS) is simple enough to skip register
definitions.

Signed-off-by: Janne Grunau <j@jannau.net>

proxyclient/hv/trace_cd3217.py

@@ -0,0 +1,119 @@
+# SPDX-License-Identifier: MIT
+
+from enum import Enum
+
+from m1n1.trace.i2c import I2CTracer, I2CDevTracer
+
+class HpmTracer(I2CDevTracer):
+    class State(Enum):
+        UNKNOWN = 0
+        REQUEST = 1
+        WRITE = 2
+        READ = 3
+
+    def __init__(self, addr=128, name=None, verbose=True):
+        print(f"CD3217Tracer.__init__(addr={addr}, name={name}, verbose={verbose})")
+        super().__init__(addr, name, verbose)
+        self.reset()
+
+    def reset(self):
+        self.reg = None
+        self.state = CD3217Tracer.State.UNKNOWN
+        self.length = None
+        self.data = []
+
+    def start(self, addr, read):
+        if addr != self.addr:
+            return
+
+        if self.state == CD3217Tracer.State.UNKNOWN:
+            if read:
+                self.state = CD3217Tracer.State.READ
+            else:
+                self.state = CD3217Tracer.State.REQUEST
+        elif self.state == CD3217Tracer.State.REQUEST and read:
+            pass
+        else:
+            self.log(f"unexpected state in start(read={read}): state:{self.state} reg:{self.reg} data:{self.data}")
+
+    def stop(self):
+        if self.state == CD3217Tracer.State.REQUEST and len(self.data) == 0:
+            return
+
+        msg = f"Txn: {self.addr:02x}."
+        if self.state == CD3217Tracer.State.REQUEST:
+            msg += f"r [{self.reg:02x}]"
+        elif self.state == CD3217Tracer.State.WRITE:
+            msg += f"w [{self.reg:02x}]"
+        elif self.state == CD3217Tracer.State.READ:
+            msg += f"r [xx]"
+        else:
+            self.log(f"unexpected state in stop(): state:{self.state} reg:{self.reg} data:{self.data}")
+            self.reset()
+            return
+
+        # only for debugging as some mismatches are expected as
+        # cd3217 seems to report the register size and not the number
+        # of requested bytes (or I2CDevTracer truncates reads).
+        #if self.length is not None and self.length > len(self.data):
+        #    self.log(f"length {self.length:02x} mismatch received data: {len(self.data):02x}")
+
+        for data in self.data:
+            msg += f" {data:02x}"
+
+        self.log(msg)
+        self.reset()
+
+    def read(self, data):
+        self.data.append(data)
+
+    def write(self, data):
+        if self.reg is None:
+            self.reg = data
+        elif self.length is None:
+            self.length = data
+            self.state = CD3217Tracer.State.WRITE
+        else:
+            self.data.append(data)
+
+class CD3217Tracer(HpmTracer):
+    def read(self, data):
+        if self.length is None:
+            self.length = data - 1
+        else:
+            self.data.append(data)
+
+
+i2c_tracers = {}
+
+for node in hv.adt["/arm-io"]:
+    if not node.name.startswith("i2c"):
+        continue
+
+    n = int(node.name[3:])
+    bus = I2CTracer(hv, f"/arm-io/{node.name}")
+
+    for mngr_node in node:
+        if "compatible" not in mngr_node._properties: # thanks Apple
+            continue
+
+        if mngr_node.compatible[0] != "usbc,manager":
+            continue
+
+        addr = mngr_node.reg[0] & 0xff
+        bus.add_device(addr, HpmTracer(addr=addr, name=mngr_node.name))
+
+        for devnode in mngr_node:
+
+            dcls = {
+                "usbc,cd3217": CD3217Tracer,
+            }.get(devnode.compatible[0], None)
+            if dcls:
+                addr = devnode.hpm_iic_addr & 0xff
+                bus.add_device(addr, dcls(addr=addr, name=devnode.name))
+
+    if len(bus.state.devices) > 1:
+        i2c_tracers[n] = bus
+
+for bus in i2c_tracers.values():
+    bus.start()