tests/ports/stm32_hardware: Convert DMA test to use unittest.

Signed-off-by: Damien George <damien@micropython.org>

tests/ports/stm32_hardware/dma_alignment.py

@@ -1,43 +1,59 @@
-from machine import SPI
 # Regression test for DMA for DCache coherency bugs with cache line
 # written originally for https://github.com/micropython/micropython/issues/13471
 
 # IMPORTANT: This test requires SPI2 MISO (pin Y8 on Pyboard D) to be connected to GND
 
+import unittest
+from machine import SPI
+
 SPI_NUM = 2
+BAUDRATE = 5_000_000
 
-spi = SPI(SPI_NUM, baudrate=5_000_000)
-buf = bytearray(1024)
-ok = True
 
-for offs in range(0, len(buf)):
-    v = memoryview(buf)[offs : offs + 128]
-    spi.readinto(v, 0xFF)
-    if not all(b == 0x00 for b in v):
-        print(offs, v.hex())
-        ok = False
+class Test(unittest.TestCase):
+    @classmethod
+    def setUpClass(cls):
+        cls.spi = SPI(SPI_NUM, baudrate=BAUDRATE)
+        cls.skip_slow_test = False
 
-print("Variable offset fixed length " + ("OK" if ok else "FAIL"))
+    def test_variable_offset_fixed_length(self):
+        buf = bytearray(1024)
+        for offs in range(0, len(buf)):
+            v = memoryview(buf)[offs : offs + 128]
+            self.spi.readinto(v, 0xFF)
+            ok = all(b == 0x00 for b in v)
+            if not ok:
+                print(offs, v.hex())
+                self.skip_slow_test = True
+            self.assertTrue(ok)
 
-# this takes around 30s to run, so skipped if already failing
-if ok:
-    for op_len in range(1, 66):
-        wr = b"\xFF" * op_len
-        for offs in range(1, len(buf) - op_len - 1):
-            # Place some "sentinel" values before and after the DMA buffer
-            before = offs & 0xFF
-            after = (~offs) & 0xFF
-            buf[offs - 1] = before
-            buf[offs + op_len] = after
-            v = memoryview(buf)[offs : offs + op_len]
-            spi.write_readinto(wr, v)
-            if (
-                not all(b == 0x00 for b in v)
-                or buf[offs - 1] != before
-                or buf[offs + op_len] != after
-            ):
-                print(v.hex())
-                print(hex(op_len), hex(offs), hex(buf[offs - 1]), hex(buf[offs + op_len]))
-                ok = False
+    def test_variable_offset_and_lengths(self):
+        # this takes around 30s to run, so skipped if already failing
+        if self.skip_slow_test:
+            self.skipTest("already failing")
 
-    print("Variable offset and lengths " + ("OK" if ok else "FAIL"))
+        buf = bytearray(1024)
+        for op_len in range(1, 66):
+            print(op_len)
+            wr = b"\xff" * op_len
+            for offs in range(1, len(buf) - op_len - 1):
+                # Place some "sentinel" values before and after the DMA buffer
+                before = offs & 0xFF
+                after = (~offs) & 0xFF
+                buf[offs - 1] = before
+                buf[offs + op_len] = after
+                v = memoryview(buf)[offs : offs + op_len]
+                self.spi.write_readinto(wr, v)
+                ok = (
+                    all(b == 0x00 for b in v)
+                    and buf[offs - 1] == before
+                    and buf[offs + op_len] == after
+                )
+                if not ok:
+                    print(v.hex())
+                    print(hex(op_len), hex(offs), hex(buf[offs - 1]), hex(buf[offs + op_len]))
+                self.assertTrue(ok)
+
+
+if __name__ == "__main__":
+    unittest.main()

tests/ports/stm32_hardware/dma_alignment.py.exp

@@ -1,2 +0,0 @@
-Variable offset fixed length OK
-Variable offset and lengths OK