Gateware: frequency multiplier for WRPLL

wrpll: add mmcm with DRP to generate 125Mhz refclk

artiq/gateware/wrpll/wrpll.py

@@ -171,3 +171,66 @@ class WRPLL(Module, AutoCSR):
         ]
 
         self.submodules.ev = SharedIRQ(self.ref_tag_ev, self.main_tag_ev)
+
+class FrequencyMultiplier(Module, AutoCSR):
+    def __init__(self, clkin):
+        clkin_se = Signal()
+        mmcm_locked = Signal()
+        mmcm_fb_clk = Signal()
+        ref_clk = Signal()
+        self.clock_domains.cd_ref = ClockDomain()
+        self.refclk_reset = CSRStorage(reset=1)
+
+        self.mmcm_bypass = CSRStorage()
+        self.mmcm_locked = CSRStatus()
+        self.mmcm_reset = CSRStorage(reset=1)
+
+        self.mmcm_daddr = CSRStorage(7)
+        self.mmcm_din = CSRStorage(16)
+        self.mmcm_dwen = CSRStorage()
+        self.mmcm_den = CSRStorage()
+        self.mmcm_dclk = CSRStorage()
+        self.mmcm_dout = CSRStatus(16)
+        self.mmcm_dready = CSRStatus()
+
+        # # #
+
+        self.specials += [
+            Instance("IBUFDS",
+                i_I=clkin.p, i_IB=clkin.n,
+                o_O=clkin_se),
+            # MMCME2 is capable to accept 10MHz input while PLLE2 only support down to 19MHz input (DS191)
+            # The MMCME2 can be reconfiged during runtime using the Dynamic Reconfiguration Ports
+            Instance("MMCME2_ADV",
+                p_BANDWIDTH="HIGH",  # lower output jitter (see https://support.xilinx.com/s/question/0D52E00006iHqRqSAK)
+                o_LOCKED=self.mmcm_locked.status,
+                i_RST=self.mmcm_reset.storage,
+                
+                p_CLKIN1_PERIOD=8, # ns
+                i_CLKIN1=clkin_se,
+                i_CLKINSEL=1,  # 1=CLKIN1 0=CLKIN2
+
+                # VCO @ 1.25GHz 
+                p_CLKFBOUT_MULT_F=10, p_DIVCLK_DIVIDE=1,
+                i_CLKFBIN=mmcm_fb_clk, o_CLKFBOUT=mmcm_fb_clk, 
+
+                # 125MHz for WRPLL
+                p_CLKOUT0_DIVIDE_F=10, p_CLKOUT0_PHASE=0.0, o_CLKOUT0=ref_clk,
+
+                # Dynamic Reconfiguration Ports
+                i_DADDR = self.mmcm_daddr.storage,
+                i_DI = self.mmcm_din.storage,
+                i_DWE = self.mmcm_dwen.storage,
+                i_DEN = self.mmcm_den.storage,
+                i_DCLK = self.mmcm_dclk.storage,
+                o_DO = self.mmcm_dout.status,
+                o_DRDY = self.mmcm_dready.status
+            ),
+            Instance("BUFGMUX",
+                i_I0=ref_clk,
+                i_I1=clkin_se,
+                i_S=self.mmcm_bypass.storage,
+                o_O=self.cd_ref.clk
+            ),
+            AsyncResetSynchronizer(self.cd_ref, self.refclk_reset.storage),
+        ]