tb/gfx_shader_bind: initial commit

1 files changed, 85 insertions, 0 deletions

diff --git a/tb/gfx_shader_bind/testbench/drivers.py b/tb/gfx_shader_bind/testbench/drivers.py
new file mode 100644
index 0000000..c069d97
--- /dev/null
+++ b/tb/gfx_shader_bind/testbench/drivers.py
@@ -0,0 +1,85 @@
+import cocotb
+from cocotb.clock import Clock
+from cocotb.queue import Queue
+from cocotb.triggers import Event, ReadOnly, RisingEdge
+
+from cocotb_bus.drivers import BusDriver
+
+from .data import BAD_PC
+
+class ClockResetDriver:
+    def __init__(self, dut):
+        self._reset_event = Event('reset_done')
+
+        dut.clk.setimmediatevalue(0)
+        dut.rst_n.setimmediatevalue(0)
+
+        self._dut = dut
+        self._clock_gen = Clock(dut.clk, 2, 'step')
+
+    def start(self):
+        cocotb.start_soon(self._clock_gen.start())
+        cocotb.start_soon(self.reset())
+
+    async def reset(self):
+        self._reset_event.clear()
+
+        self._dut.rst_n.value = 0
+        await RisingEdge(self._dut.clk)
+        self._dut.rst_n.value = 1
+        await ReadOnly()
+
+        self._reset_event.set()
+
+    async def wait_for_reset(self):
+        await self._reset_event.wait()
+
+class PcDriver(BusDriver):
+    _signals = ['pc', 'group']
+
+    def __init__(self, *args, table, **kwargs):
+        super().__init__(*args, **kwargs)
+
+        self._table = table
+        self._delay1 = BAD_PC
+        self._delay2 = BAD_PC
+        self._delay3 = BAD_PC
+
+        cocotb.start_soon(self._run())
+
+    async def _run(self):
+        while True:
+            self.bus.pc.value = self._delay3
+
+            await RisingEdge(self.clock)
+
+            self._delay3 = self._delay2
+            self._delay2 = self._delay1
+            self._delay1 = self._table[self.bus.group.value]
+
+class LoopDriver(BusDriver):
+    _signals = ['group', 'valid']
+
+    def __init__(self, *args, maxsize=8, **kwargs):
+        super().__init__(*args, **kwargs)
+
+        self._queue = Queue(maxsize=maxsize)
+        self.bus.valid.setimmediatevalue(0)
+
+        cocotb.start_soon(self._run())
+
+    async def put(self, group):
+        await self._queue.put(group)
+
+    async def _run(self):
+        while True:
+            await RisingEdge(self.clock)
+
+            valid = not self._queue.empty()
+            if valid:
+                group = self._queue.get_nowait()
+                valid = group is not None
+
+            self.bus.valid.value = int(valid)
+            if valid:
+                self.bus.group.value = group