soc/add_sdcard: add with_emulator parameter to use SDCard emulator (from Google Project Vault) and integrate it in litex_sim.

litex/soc/integration/soc.py

@@ -1245,9 +1245,7 @@ class LiteXSoC(SoC):
         self.add_csr(name)
 
     # Add SDCard -----------------------------------------------------------------------------------
-    def add_sdcard(self, name="sdcard"):
-        assert self.platform.device[:3] == "xc7" # FIXME: Only supports 7-Series for now.
-
+    def add_sdcard(self, name="sdcard", with_emulator=False):
         # Imports
         from litesdcard.phy import SDPHY
         from litesdcard.clocker import SDClockerS7
@@ -1255,11 +1253,26 @@ class LiteXSoC(SoC):
         from litesdcard.bist import BISTBlockGenerator, BISTBlockChecker
         from litesdcard.data import SDDataReader, SDDataWriter
 
+        # Emulator
+        if with_emulator:
+            from litesdcard.emulator import SDEmulator, _sdemulator_pads
+            sdcard_pads = _sdemulator_pads()
+            self.submodules.sdemulator = SDEmulator(self.platform, sdcard_pads)
+            self.add_csr("sdemulator")
+        else:
+            assert self.platform.device[:3] == "xc7" # FIXME: Only supports 7-Series for now.
+            sdcard_pads = self.platform.request(name)
+
         # Core
-        sdcard_pads = self.platform.request(name)
         if hasattr(sdcard_pads, "rst"):
             self.comb += sdcard_pads.rst.eq(0)
-        self.submodules.sdclk   = SDClockerS7(sys_clk_freq=self.sys_clk_freq)
+        if with_emulator:
+            self.clock_domains.cd_sd    = ClockDomain("sd")
+            self.clock_domains.cd_sd_fb = ClockDomain("sd_fb")
+            self.comb += self.cd_sd.clk.eq(ClockSignal())
+            self.comb += self.cd_sd_fb.clk.eq(ClockSignal())
+        else:
+            self.submodules.sdclk = SDClockerS7(sys_clk_freq=self.sys_clk_freq)
         self.submodules.sdphy   = SDPHY(sdcard_pads, self.platform.device)
         self.submodules.sdcore  = SDCore(self.sdphy, csr_data_width=self.csr_data_width)
         self.submodules.sdtimer = Timer()
@@ -1293,9 +1306,10 @@ class LiteXSoC(SoC):
         self.comb += self.sddatawriter.source.connect(self.sdcore.sink),
 
         # Timing constraints
-        self.platform.add_period_constraint(self.sdclk.cd_sd.clk,    1e9/self.sys_clk_freq)
-        self.platform.add_period_constraint(self.sdclk.cd_sd_fb.clk, 1e9/self.sys_clk_freq)
-        self.platform.add_false_path_constraints(
-            self.crg.cd_sys.clk,
-            self.sdclk.cd_sd.clk,
-            self.sdclk.cd_sd_fb.clk)
+        if not with_emulator:
+            self.platform.add_period_constraint(self.sdclk.cd_sd.clk,    1e9/self.sys_clk_freq)
+            self.platform.add_period_constraint(self.sdclk.cd_sd_fb.clk, 1e9/self.sys_clk_freq)
+            self.platform.add_false_path_constraints(
+                self.crg.cd_sys.clk,
+                self.sdclk.cd_sd.clk,
+                self.sdclk.cd_sd_fb.clk)

litex/tools/litex_sim.py

@@ -177,6 +177,7 @@ class SimSoC(SoCCore):
         sdram_spd_data        = None,
         sdram_verbosity       = 0,
         with_i2c              = False,
+        with_sdcard           = False,
         **kwargs):
         platform     = Platform()
         sys_clk_freq = int(1e6)
@@ -306,6 +307,10 @@ class SimSoC(SoCCore):
             self.submodules.i2c = I2CMasterSim(pads)
             self.add_csr("i2c")
 
+        # SDCard -----------------------------------------------------------------------------------
+        if with_sdcard:
+            self.add_sdcard("sdcard", with_emulator=True)
+
 # Build --------------------------------------------------------------------------------------------
 
 def main():
@@ -327,6 +332,7 @@ def main():
     parser.add_argument("--remote-ip",            default="192.168.1.100", help="Remote IP address of TFTP server (default=192.168.1.100)")
     parser.add_argument("--with-analyzer",        action="store_true",     help="Enable Analyzer support")
     parser.add_argument("--with-i2c",             action="store_true",     help="Enable I2C support")
+    parser.add_argument("--with-sdcard",          action="store_true",     help="Enable SDCard support")
     parser.add_argument("--trace",                action="store_true",     help="Enable Tracing")
     parser.add_argument("--trace-fst",            action="store_true",     help="Enable FST tracing (default=VCD)")
     parser.add_argument("--trace-start",          default=0,               help="Cycle to start tracing")
@@ -376,6 +382,7 @@ def main():
         with_etherbone = args.with_etherbone,
         with_analyzer  = args.with_analyzer,
         with_i2c       = args.with_i2c,
+        with_sdcard    = args.with_sdcard,
         sdram_init     = [] if args.sdram_init is None else get_mem_data(args.sdram_init, cpu_endianness),
         **soc_kwargs)
     if args.ram_init is not None: