targets/ulx3s: use pll for phase shift, enable refresh, memtest ok

litex/boards/targets/ulx3s.py

@@ -13,47 +13,33 @@ from litex.soc.integration.builder import *
 
 from litedram.modules import MT48LC16M16
 from litedram.phy import GENSDRPHY
-from litedram.core.controller import ControllerSettings
 
 
 class _CRG(Module):
     def __init__(self, platform):
         self.clock_domains.cd_sys = ClockDomain()
-        self.clock_domains.cd_sys_ps = ClockDomain()
+        self.clock_domains.cd_sys_ps = ClockDomain(reset_less=True)
 
         # # #
 
         # clk / rst
         clk25 = platform.request("clk25")
         rst = platform.request("rst")
-        platform.add_period_constraint(clk25, 40.0)
 
         # pll
         self.submodules.pll = pll = ECP5PLL()
         self.comb += pll.reset.eq(rst)
         pll.register_clkin(clk25, 25e6)
-        pll.create_clkout(self.cd_sys, 50e6)
+        pll.create_clkout(self.cd_sys, 50e6, phase=11)
+        pll.create_clkout(self.cd_sys_ps, 50e6, phase=20)
         # FIXME: AsyncResetSynchronizer needs FD1S3BX support.
         #self.specials += AsyncResetSynchronizer(self.cd_sys, rst)
         self.comb += self.cd_sys.rst.eq(rst)
+        platform.add_period_constraint(self.cd_sys.clk, 20.0)
+        platform.add_period_constraint(self.cd_sys_ps.clk, 20.0)
 
-        # sys_clk phase shifted (for sdram)
+        # sdram clock
-        sdram_ps_clk = self.cd_sys.clk
+        self.comb += platform.request("sdram_clock").eq(self.cd_sys_ps.clk)
-        # FIXME: phase shift with luts, needs PLL support.
-        sdram_ps_luts = 5
-        for i in range(sdram_ps_luts):
-            new_sdram_ps_clk = Signal()
-            self.specials += Instance("LUT4",
-                p_INIT=2,
-                i_A=sdram_ps_clk,
-                i_B=0,
-                i_C=0,
-                i_D=0,
-                o_Z=new_sdram_ps_clk)
-            sdram_ps_clk = new_sdram_ps_clk
-        self.comb += self.cd_sys_ps.clk.eq(sdram_ps_clk)
-        sdram_clock = platform.request("sdram_clock")
-        self.comb += sdram_clock.eq(sdram_ps_clk)
 
         # Stop ESP32 from resetting FPGA
         wifi_gpio0 = platform.request("wifi_gpio0")
@@ -63,9 +49,8 @@ class _CRG(Module):
 class BaseSoC(SoCSDRAM):
     def __init__(self, **kwargs):
         platform = ulx3s.Platform(toolchain="trellis")
-        sys_clk_freq = int(25e6)
+        sys_clk_freq = int(50e6)
         SoCSDRAM.__init__(self, platform, clk_freq=sys_clk_freq,
-                          l2_size=32,
                           integrated_rom_size=0x8000,
                           **kwargs)
 
@@ -76,10 +61,7 @@ class BaseSoC(SoCSDRAM):
             sdram_module = MT48LC16M16(sys_clk_freq, "1:1")
             self.register_sdram(self.sdrphy,
                                 sdram_module.geom_settings,
-                                sdram_module.timing_settings,
+                                sdram_module.timing_settings)
-                                controller_settings=ControllerSettings(
-                                    with_refresh=False)) # FIXME
-
 
 def main():
     parser = argparse.ArgumentParser(description="LiteX SoC port to the ULX3S")
@@ -91,6 +73,5 @@ def main():
     builder = Builder(soc, **builder_argdict(args))
     builder.build()
 
-
 if __name__ == "__main__":
     main()