tests/multi_pyb_can: Add multitests for pyboard CAN controller.

Currently only classic CAN, but tests run on both the stm32 classic CAN
controller and the FD-CAN controller with the same results.

Signed-off-by: Angus Gratton <angus@redyak.com.au>

tests/multi_pyb_can/rx_callback.py

@@ -0,0 +1,98 @@
+from pyb import CAN
+import time
+import errno
+
+# Test the various receive IRQs, including overflow
+
+rx_overflow = False
+
+REASONS = ["received", "full", "overflow"]
+
+# CAN IDs
+ID_SPAM = 0x345  # messages spammed into the receive FIFO
+ID_ACK_OFLOW = 0x055  # message the receiver sends after it's seen an overflow
+ID_AFTER = 0x100  # message the sender sends after the ACK
+
+
+def cb0(bus, reason):
+    global rx_overflow
+    if reason != 0 and not rx_overflow:
+        # exact timing of 'received' callbacks depends on controller type,
+        # so only log the other two
+        print("rx0 reason", REASONS[reason])
+    if reason == 2:
+        rx_overflow = True
+
+
+# Accept all standard IDs on FIFO 0
+def _enable_accept_all():
+    if hasattr(CAN, "MASK"):  # FD-CAN controller
+        can.setfilter(0, CAN.RANGE, 0, (0x0, 0x7FF), extframe=False)
+    else:
+        can.setfilter(0, CAN.MASK16, 0, (0, 0, 0, 0), extframe=False)
+
+
+# Receiver
+def instance0():
+    _enable_accept_all()
+    can.rxcallback(0, cb0)
+
+    multitest.next()
+    multitest.wait("sender ready")
+    multitest.broadcast("receiver ready")
+
+    while not rx_overflow:
+        pass  # Resume ASAP after FIFO0 overflows
+
+    can.send(b"overflow", ID_ACK_OFLOW)
+
+    # drain the receive FIFO, making sure we read at least on ID_SPAM message
+    rxed_spam = False
+    while can.any(0):
+        msg = can.recv(0, timeout=0)
+        assert msg[0] == ID_SPAM
+        rxed_spam = True
+    print("rxed_spam", rxed_spam)
+
+    # This should be the one message with ID_AFTER, there may be one or two spam messages as well
+    for _ in range(10):
+        msg = can.recv(0, timeout=500)
+        if msg[0] == ID_AFTER:
+            print(msg)
+            break
+
+    # RX FIFO should be empty now
+    print("any", can.any(0))
+
+
+# Sender
+def instance1():
+    _enable_accept_all()
+    multitest.next()
+    multitest.broadcast("sender ready")
+    multitest.wait("receiver ready")
+
+    # Spam out messages until the receiver tells us its RX FIFO is full.
+    #
+    # The RX FIFO on the receiver can vary from 3 deep (BXCAN) to 25 deep (STM32H7),
+    # so we keep sending to it until we see a CAN message on ID_ACK_OFLOW indicating
+    # the receiver's FIFO has overflowed
+    for i in range(255):
+        can.send(bytes([i] * 8), ID_SPAM, timeout=25)
+        if can.any(0):
+            print(can.recv(0))  # should be ID_ACK_OFLOW
+            break
+        # on boards like STM32H7 the TX FIFO is really deep, so don't fill it too quickly...
+        time.sleep_ms(1)
+
+    # give the receiver some time to make space in the FIFO
+    time.sleep_ms(200)
+
+    # send the final message, the receiver should get this one
+    can.send(b"aaaaa", ID_AFTER)
+
+    # Sender's RX FIFO should also be empty at this point
+    print("any", can.any(0))
+
+
+can = CAN(1, CAN.NORMAL, baudrate=500_000, sample_point=75)

tests/multi_pyb_can/rx_callback.py.exp

@@ -0,0 +1,9 @@
+--- instance0 ---
+rx0 reason full
+rx0 reason overflow
+rxed_spam True
+(256, False, False, 0, b'aaaaa')
+any False
+--- instance1 ---
+(85, False, False, 0, b'overflow')
+any False

tests/multi_pyb_can/rx_filters.py

@@ -0,0 +1,50 @@
+from pyb import CAN
+import time
+import errno
+
+# Test for the filtering capabilities for RX FIFO 0 and 1.
+
+
+# Receiver
+def instance0():
+    # Configure to receive standard frames (in a range) on FIFO 0
+    # and extended frames (in a range) on FIFO 1.
+    if hasattr(CAN, "MASK"):
+        # FD-CAN has independent filter banks for standard and extended IDs
+        can.setfilter(0, CAN.MASK, 0, (0x300, 0x700), extframe=False)
+        can.setfilter(0, CAN.MASK, 1, (0x3000, 0x7000), extframe=True)
+    else:
+        # pyb.CAN only supports MASK32 for extended ids
+        can.setfilter(0, CAN.MASK16, 0, (0x300, 0x700, 0x300, 0x700), extframe=False)
+        can.setfilter(1, CAN.MASK32, 1, (0x3000, 0x7000), extframe=True)
+
+    multitest.next()
+    multitest.wait("sender ready")
+    multitest.broadcast("receiver ready")
+    for i in range(3):
+        print(i)
+        print("fifo0", can.recv(0, timeout=200))
+        print("fifo1", can.recv(1, timeout=200))
+
+    try:
+        can.recv(0, timeout=100)  # should time out
+    except OSError as e:
+        assert e.errno == errno.ETIMEDOUT
+        print("Timed out as expected")
+
+
+# Sender
+def instance1():
+    multitest.next()
+    multitest.broadcast("sender ready")
+    multitest.wait("receiver ready")
+
+    for i in range(3):
+        print(i)
+        can.send(bytes([i, 3] * i), 0x345)
+        can.send(bytes([0xEE] * i), 0x3700 + i, extframe=True)
+        can.send(b"abcdef", 0x123)  # matches no filter, expect ACKed but not received
+        time.sleep_ms(5)  # avoid flooding either our or the receiver's FIFO
+
+
+can = CAN(1, CAN.NORMAL, baudrate=500_000, sample_point=75)

tests/multi_pyb_can/rx_filters.py.exp

@@ -0,0 +1,15 @@
+--- instance0 ---
+0
+fifo0 (837, False, False, 0, b'')
+fifo1 (14080, True, False, 0, b'')
+1
+fifo0 (837, False, False, 0, b'\x01\x03')
+fifo1 (14081, True, False, 0, b'\xee')
+2
+fifo0 (837, False, False, 0, b'\x02\x03\x02\x03')
+fifo1 (14082, True, False, 0, b'\xee\xee')
+Timed out as expected
+--- instance1 ---
+0
+1
+2