# This file is Copyright (c) 2020 Antmicro # License: BSD import os import csv import unittest import litedram.modules from litedram.modules import SDRAMModule, DDR3SPDData def load_spd_reference(filename): """Load reference SPD data from a CSV file Micron reference SPD data can be obtained from: https://www.micron.com/support/tools-and-utilities/serial-presence-detect """ script_dir = os.path.dirname(os.path.realpath(__file__)) path = os.path.join(script_dir, "spd_data", filename) data = [0] * 256 with open(path) as f: reader = csv.DictReader(f) for row in reader: address = row["Byte Number"] value = row["Byte Value"] # Ignore ranges (data we care about is specified per byte anyway) if len(address.split("-")) == 1: data[int(address)] = int(value, 16) return data class TestSPD(unittest.TestCase): def test_tck_to_speedgrade(self): # Verify that speedgrade transfer rates are calculated correctly from tck tck_to_speedgrade = { 2.5: 800, 1.875: 1066, 1.5: 1333, 1.25: 1600, 1.071: 1866, 0.938: 2133, } for tck, speedgrade in tck_to_speedgrade.items(): self.assertEqual(speedgrade, DDR3SPDData.speedgrade_freq(tck)) def compare_geometry(self, module, module_ref): self.assertEqual(module.nbanks, module_ref.nbanks) self.assertEqual(module.nrows, module_ref.nrows) self.assertEqual(module.ncols, module_ref.ncols) def compare_technology_timings(self, module, module_ref, omit=None): timings = {"tREFI", "tWTR", "tCCD", "tRRD", "tZQCS"} if omit is not None: timings -= omit for timing in timings: txx = getattr(module.technology_timings, timing) txx_ref = getattr(module_ref.technology_timings, timing) with self.subTest(txx=timing): self.assertEqual(txx, txx_ref) def compare_speedgrade_timings(self, module, module_ref, omit=None): timings = {"tRP", "tRCD", "tWR", "tRFC", "tFAW", "tRAS"} if omit is not None: timings -= omit for freq, speedgrade_timings in module.speedgrade_timings.items(): if freq == "default": continue for timing in timings: txx = getattr(speedgrade_timings, timing) txx_ref = getattr(module_ref.speedgrade_timings[freq], timing) with self.subTest(freq=freq, txx=timing): self.assertEqual(txx, txx_ref) def compare_modules(self, module, module_ref, omit=None): self.assertEqual(module.memtype, module_ref.memtype) self.assertEqual(module.rate, module_ref.rate) self.compare_geometry(module, module_ref) self.compare_technology_timings(module, module_ref, omit=omit) self.compare_speedgrade_timings(module, module_ref, omit=omit) def test_MT16KTF1G64HZ(self): kwargs = dict(clk_freq=125e6, rate="1:4") module_ref = litedram.modules.MT16KTF1G64HZ(**kwargs) with self.subTest(speedgrade="-1G6"): data = load_spd_reference("MT16KTF1G64HZ-1G6P1.csv") module = SDRAMModule.from_spd_data(data, kwargs["clk_freq"]) self.compare_modules(module, module_ref) sgt = module.speedgrade_timings["1600"] self.assertEqual(sgt.tRP, 13.125) self.assertEqual(sgt.tRCD, 13.125) self.assertEqual(sgt.tRP + sgt.tRAS, 48.125) with self.subTest(speedgrade="-1G9"): data = load_spd_reference("MT16KTF1G64HZ-1G9E1.csv") module = SDRAMModule.from_spd_data(data, kwargs["clk_freq"]) # tRRD it different for this speedgrade self.compare_modules(module, module_ref, omit={"tRRD"}) self.assertEqual(module.technology_timings.tRRD, (4, 5)) sgt = module.speedgrade_timings["1866"] self.assertEqual(sgt.tRP, 13.125) self.assertEqual(sgt.tRCD, 13.125) self.assertEqual(sgt.tRP + sgt.tRAS, 47.125) def test_MT18KSF1G72HZ(self): kwargs = dict(clk_freq=125e6, rate="1:4") module_ref = litedram.modules.MT18KSF1G72HZ(**kwargs) with self.subTest(speedgrade="-1G6"): data = load_spd_reference("MT18KSF1G72HZ-1G6E2.csv") module = SDRAMModule.from_spd_data(data, kwargs["clk_freq"]) self.compare_modules(module, module_ref) sgt = module.speedgrade_timings["1600"] self.assertEqual(sgt.tRP, 13.125) self.assertEqual(sgt.tRCD, 13.125) self.assertEqual(sgt.tRP + sgt.tRAS, 48.125) with self.subTest(speedgrade="-1G4"): data = load_spd_reference("MT18KSF1G72HZ-1G4E2.csv") module = SDRAMModule.from_spd_data(data, kwargs["clk_freq"]) self.compare_modules(module, module_ref) sgt = module.speedgrade_timings["1333"] self.assertEqual(sgt.tRP, 13.125) self.assertEqual(sgt.tRCD, 13.125) self.assertEqual(sgt.tRP + sgt.tRAS, 49.125) def test_MT8JTF12864(self): kwargs = dict(clk_freq=125e6, rate="1:4") module_ref = litedram.modules.MT8JTF12864(**kwargs) data = load_spd_reference("MT8JTF12864AZ-1G4G1.csv") module = SDRAMModule.from_spd_data(data, kwargs["clk_freq"]) self.compare_modules(module, module_ref) sgt = module.speedgrade_timings["1333"] self.assertEqual(sgt.tRP, 13.125) self.assertEqual(sgt.tRCD, 13.125) self.assertEqual(sgt.tRP + sgt.tRAS, 49.125) def test_MT8KTF51264(self): kwargs = dict(clk_freq=100e6, rate="1:4") module_ref = litedram.modules.MT8KTF51264(**kwargs) with self.subTest(speedgrade="-1G4"): data = load_spd_reference("MT8KTF51264HZ-1G4E1.csv") module = SDRAMModule.from_spd_data(data, kwargs["clk_freq"]) self.compare_modules(module, module_ref) sgt = module.speedgrade_timings["1333"] self.assertEqual(sgt.tRP, 13.125) self.assertEqual(sgt.tRCD, 13.125) self.assertEqual(sgt.tRP + sgt.tRAS, 49.125) with self.subTest(speedgrade="-1G6"): data = load_spd_reference("MT8KTF51264HZ-1G6E1.csv") module = SDRAMModule.from_spd_data(data, kwargs["clk_freq"]) self.compare_modules(module, module_ref) sgt = module.speedgrade_timings["1600"] self.assertEqual(sgt.tRP, 13.125) self.assertEqual(sgt.tRCD, 13.125) self.assertEqual(sgt.tRP + sgt.tRAS, 48.125) with self.subTest(speedgrade="-1G9"): data = load_spd_reference("MT8KTF51264HZ-1G9P1.csv") module = SDRAMModule.from_spd_data(data, kwargs["clk_freq"]) # tRRD different for this timing self.compare_modules(module, module_ref, omit={"tRRD"}) self.assertEqual(module.technology_timings.tRRD, (4, 5)) sgt = module.speedgrade_timings["1866"] self.assertEqual(sgt.tRP, 13.125) self.assertEqual(sgt.tRCD, 13.125) self.assertEqual(sgt.tRP + sgt.tRAS, 47.125)