tests: Test hardware timers as well as software timers.

On platforms where hardware timers are available, test these in each
combination of hard/soft and one-shot/periodic in the same way as for
software timers. Where a platform supports both software (id = -1) and
hardware (id >= 0) timers, the behaviour of both is now checked.

For now, esp8266 is the only platform that supports hardware timers and
both hard and soft callbacks.

Signed-off-by: Chris Webb <chris@arachsys.com>

tests/extmod/machine_hard_timer.py

@@ -0,0 +1,45 @@
+import sys
+
+try:
+    from machine import Timer
+    from time import sleep_ms
+except:
+    print("SKIP")
+    raise SystemExit
+
+if sys.platform == "esp8266":
+    timer = Timer(0)
+else:
+    # Hardware timers are not implemented.
+    print("SKIP")
+    raise SystemExit
+
+# Test both hard and soft IRQ handlers and both one-shot and periodic
+# timers. We adjust period in tests/extmod/machine_soft_timer.py, so try
+# adjusting freq here instead. The heap should be locked in hard callbacks
+# and unlocked in soft callbacks.
+
+
+def callback(t):
+    print("callback", mode[1], kind[1], freq, end=" ")
+    try:
+        allocate = bytearray(1)
+        print("unlocked")
+    except MemoryError:
+        print("locked")
+
+
+modes = [(Timer.ONE_SHOT, "one-shot"), (Timer.PERIODIC, "periodic")]
+kinds = [(False, "soft"), (True, "hard")]
+
+for mode in modes:
+    for kind in kinds:
+        for freq in 50, 25:
+            timer.init(
+                mode=mode[0],
+                freq=freq,
+                hard=kind[0],
+                callback=callback,
+            )
+            sleep_ms(90)
+            timer.deinit()

tests/extmod/machine_hard_timer.py.exp

@@ -0,0 +1,16 @@
+callback one-shot soft 50 unlocked
+callback one-shot soft 25 unlocked
+callback one-shot hard 50 locked
+callback one-shot hard 25 locked
+callback periodic soft 50 unlocked
+callback periodic soft 50 unlocked
+callback periodic soft 50 unlocked
+callback periodic soft 50 unlocked
+callback periodic soft 25 unlocked
+callback periodic soft 25 unlocked
+callback periodic hard 50 locked
+callback periodic hard 50 locked
+callback periodic hard 50 locked
+callback periodic hard 50 locked
+callback periodic hard 25 locked
+callback periodic hard 25 locked