From eddd6e4eaff5d27bd7ff35f770c097f6c14b16e9 Mon Sep 17 00:00:00 2001 From: Florent Kermarrec Date: Tue, 3 Dec 2019 12:17:57 +0100 Subject: [PATCH] modules/init: add DDR4 fine refresh mode support: x1, x2 and x4 (x1=previous and default behavior) --- litedram/init.py | 11 +++++++++- litedram/modules.py | 49 +++++++++++++++++++++++++++++---------------- 2 files changed, 42 insertions(+), 18 deletions(-) diff --git a/litedram/init.py b/litedram/init.py index 1043f98..897583e 100644 --- a/litedram/init.py +++ b/litedram/init.py @@ -298,6 +298,15 @@ def get_ddr4_phy_init_sequence(phy_settings, timing_settings): mr2 |= rtt_wr << 9 return mr2 + def format_mr3(fine_refresh_mode): + fine_refresh_mode_to_mr3 = { + "1x": 0b000, + "2x": 0b001, + "4x": 0b010 + } + mr3 = fine_refresh_mode_to_mr3[fine_refresh_mode] << 6 + return mr3 + def format_mr6(tccd): tccd_to_mr6 = { 4: 0b000, @@ -350,7 +359,7 @@ def get_ddr4_phy_init_sequence(phy_settings, timing_settings): mr0 = format_mr0(bl, cl, wr, 1) mr1 = format_mr1(1, z_to_ron[ron], z_to_rtt_nom[rtt_nom]) mr2 = format_mr2(cwl, z_to_rtt_wr[rtt_wr]) - mr3 = 0 + mr3 = format_mr3(timing_settings.fine_refresh_mode) mr4 = 0 mr5 = 0 mr6 = format_mr6(4) # FIXME: tCCD diff --git a/litedram/modules.py b/litedram/modules.py index 0301d15..cb3f640 100644 --- a/litedram/modules.py +++ b/litedram/modules.py @@ -46,7 +46,7 @@ class SDRAMModule: SDRAM modules with the same geometry exist can have various speedgrades. """ - def __init__(self, clk_freq, rate, speedgrade=None): + def __init__(self, clk_freq, rate, speedgrade=None, fine_refresh_mode=None): self.clk_freq = clk_freq self.rate = rate self.speedgrade = speedgrade @@ -55,12 +55,16 @@ class SDRAMModule: rowbits = log2_int(self.nrows), colbits = log2_int(self.ncols), ) + assert not (self.memtype != "DDR4" and fine_refresh_mode != None) + assert fine_refresh_mode in [None, "1x", "2x", "4x"] + if (fine_refresh_mode is None) and (self.memtype == "DDR4"): + fine_refresh_mode = "1x" self.timing_settings = TimingSettings( tRP = self.ns_to_cycles(self.get("tRP")), tRCD = self.ns_to_cycles(self.get("tRCD")), tWR = self.ns_to_cycles(self.get("tWR")), - tREFI = self.ns_to_cycles(self.get("tREFI"), False), - tRFC = self.ck_ns_to_cycles(*self.get("tRFC")), + tREFI = self.ns_to_cycles(self.get("tREFI", fine_refresh_mode), False), + tRFC = self.ck_ns_to_cycles(*self.get("tRFC", fine_refresh_mode)), tWTR = self.ck_ns_to_cycles(*self.get("tWTR")), tFAW = None if self.get("tFAW") is None else self.ck_ns_to_cycles(*self.get("tFAW")), tCCD = None if self.get("tCCD") is None else self.ck_ns_to_cycles(*self.get("tCCD")), @@ -69,26 +73,31 @@ class SDRAMModule: tRAS = None if self.get("tRAS") is None else self.ns_to_cycles(self.get("tRAS")), tZQCS = None if self.get("tZQCS") is None else self.ck_ns_to_cycles(*self.get("tZQCS")) ) + self.timing_settings.fine_refresh_mode = fine_refresh_mode - def get(self, name): + def get(self, name, key=None): + r = None if name in _speedgrade_timings: if hasattr(self, "speedgrade_timings"): speedgrade = "default" if self.speedgrade is None else self.speedgrade - return getattr(self.speedgrade_timings[speedgrade], name) + r = getattr(self.speedgrade_timings[speedgrade], name) else: name = name + "_" + self.speedgrade if self.speedgrade is not None else name try: - return getattr(self, name) + r = getattr(self, name) except: - return None + pass else: if hasattr(self, "technology_timings"): - return getattr(self.technology_timings, name) + r = getattr(self.technology_timings, name) else: try: - return getattr(self, name) + r = getattr(self, name) except: - return None + pass + if (r is not None) and (key is not None): + r = r[key] + return r def ns_to_cycles(self, t, margin=True): clk_period_ns = 1e9/self.clk_freq @@ -462,9 +471,11 @@ class EDY4016A(SDRAMModule): nrows = 32768 ncols = 1024 # timings - technology_timings = _TechnologyTimings(tREFI=64e6/8192, tWTR=(4, 7.5), tCCD=(4, None), tRRD=(4, 4.9), tZQCS=(128, 80)) + trefi = {"1x": 64e6/8192, "2x": (64e6/8192)/2, "4x": (64e6/8192)/4} + trfc = {"1x": (None, 260), "2x": (None, 160), "4x": (None, 110)} + technology_timings = _TechnologyTimings(tREFI=trefi, tWTR=(4, 7.5), tCCD=(4, None), tRRD=(4, 4.9), tZQCS=(128, 80)) speedgrade_timings = { - "2400": _SpeedgradeTimings(tRP=13.32, tRCD=13.32, tWR=15, tRFC=(None, 260), tFAW=(28, 30), tRAS=32), + "2400": _SpeedgradeTimings(tRP=13.32, tRCD=13.32, tWR=15, tRFC=trfc, tFAW=(28, 30), tRAS=32), } speedgrade_timings["default"] = speedgrade_timings["2400"] @@ -478,10 +489,12 @@ class MT40A1G8(SDRAMModule): nrows = 65536 ncols = 1024 # timings - technology_timings = _TechnologyTimings(tREFI=64e6/8192, tWTR=(4, 7.5), tCCD=(4, None), tRRD=(4, 6.4), tZQCS=(128, 80)) + trefi = {"1x": 64e6/8192, "2x": (64e6/8192)/2, "4x": (64e6/8192)/4} + trfc = {"1x": (None, 350), "2x": (None, 260), "4x": (None, 160)} + technology_timings = _TechnologyTimings(tREFI=trefi, tWTR=(4, 7.5), tCCD=(4, None), tRRD=(4, 6.4), tZQCS=(128, 80)) speedgrade_timings = { - "2400": _SpeedgradeTimings(tRP=13.32, tRCD=13.32, tWR=15, tRFC=(None, 350), tFAW=(20, 25), tRAS=32), - "2666": _SpeedgradeTimings(tRP=13.50, tRCD=13.50, tWR=15, tRFC=(None, 350), tFAW=(20, 21), tRAS=32), + "2400": _SpeedgradeTimings(tRP=13.32, tRCD=13.32, tWR=15, tRFC=trfc, tFAW=(20, 25), tRAS=32), + "2666": _SpeedgradeTimings(tRP=13.50, tRCD=13.50, tWR=15, tRFC=trfc, tFAW=(20, 21), tRAS=32), } speedgrade_timings["default"] = speedgrade_timings["2400"] @@ -495,8 +508,10 @@ class MT40A512M16(SDRAMModule): nrows = 65536 ncols = 1024 # timings - technology_timings = _TechnologyTimings(tREFI=64e6/8192, tWTR=(4, 7.5), tCCD=(4, None), tRRD=(4, 4.9), tZQCS=(128, 80)) + trefi = {"1x": 64e6/8192, "2x": (64e6/8192)/2, "4x": (64e6/8192)/4} + trfc = {"1x": (None, 350), "2x": (None, 260), "4x": (None, 160)} + technology_timings = _TechnologyTimings(tREFI=trefi, tWTR=(4, 7.5), tCCD=(4, None), tRRD=(4, 4.9), tZQCS=(128, 80)) speedgrade_timings = { - "2400": _SpeedgradeTimings(tRP=13.32, tRCD=13.32, tWR=15, tRFC=(None, 350), tFAW=(20, 25), tRAS=32), + "2400": _SpeedgradeTimings(tRP=13.32, tRCD=13.32, tWR=15, tRFC=trfc, tFAW=(20, 25), tRAS=32), } speedgrade_timings["default"] = speedgrade_timings["2400"]