soc/SoCController: add uptime since start (disabled by default) and a…

…llow features to be enabled/disabled.

litex/soc/integration/soc.py

@@ -611,30 +611,49 @@ def __str__(self):
 # SoCController ------------------------------------------------------------------------------------
 
 class SoCController(Module, AutoCSR):
-    def __init__(self):
-        self._reset      = CSRStorage(1, description="""
-            Write a ``1`` to this register to reset the SoC.""")
-        self._scratch    = CSRStorage(32, reset=0x12345678, description="""
-            Use this register as a scratch space to verify that software read/write accesses
-            to the Wishbone/CSR bus are working correctly. The initial reset value of 0x1234578
-            can be used to verify endianness.""")
-        self._bus_errors = CSRStatus(32, description="""
-            Total number of Wishbone bus errors (timeouts) since last reset.""")
+    def __init__(self,
+        with_reset    = True,
+        with_scratch  = True,
+        with_errors   = True,
+        with_uptime   = False):
+
+        if with_reset:
+            self._reset = CSRStorage(1, description="""Write a ``1`` to this register to reset the SoC.""")
+        if with_scratch:
+            self._scratch = CSRStorage(32, reset=0x12345678, description="""
+                Use this register as a scratch space to verify that software read/write accesses
+                to the Wishbone/CSR bus are working correctly. The initial reset value of 0x1234578
+                can be used to verify endianness.""")
+        if with_errors:
+            self._bus_errors = CSRStatus(32, description="Total number of Wishbone bus errors (timeouts) since start.")
+
+        if with_uptime:
+            self._uptime_latch = CSRStorage(description="Write a ``1`` to latch current uptime to ``time`` register.")
+            self._uptime       = CSRStatus(64, description="Latched uptime since start (in ``sys_clk`` cycles).")
 
         # # #
 
         # Reset
-        self.reset = Signal()
-        self.comb += self.reset.eq(self._reset.re)
-
-        # Bus errors
-        self.bus_error = Signal()
-        bus_errors     = Signal(32)
-        self.sync += \
-            If(bus_errors != (2**len(bus_errors)-1),
-                If(self.bus_error, bus_errors.eq(bus_errors + 1))
-            )
-        self.comb += self._bus_errors.status.eq(bus_errors)
+        if with_reset:
+            self.reset = Signal()
+            self.comb += self.reset.eq(self._reset.re)
+
+        # Errors
+        if with_errors:
+            self.bus_error = Signal()
+            bus_errors     = Signal(32)
+            self.sync += [
+                If(bus_errors != (2**len(bus_errors)-1),
+                    If(self.bus_error, bus_errors.eq(bus_errors + 1))
+                )
+            ]
+            self.comb += self._bus_errors.status.eq(bus_errors)
+
+        # Uptime
+        if with_uptime:
+            uptime = Signal(64, reset_less=True)
+            self.sync += uptime.eq(uptime + 1)
+            self.sync += If(self._uptime_latch.re, self._uptime.status.eq(uptime))
 
 # SoC ----------------------------------------------------------------------------------------------
 
@@ -736,9 +755,9 @@ def add_config(self, name, value=None):
             self.add_constant(name, value)
 
     # SoC Main Components --------------------------------------------------------------------------
-    def add_controller(self, name="ctrl"):
+    def add_controller(self, name="ctrl", **kwargs):
         self.check_if_exists(name)
-        setattr(self.submodules, name, SoCController())
+        setattr(self.submodules, name, SoCController(**kwargs))
         self.csr.add(name, use_loc_if_exists=True)
 
     def add_ram(self, name, origin, size, contents=[], mode="rw"):
@@ -794,8 +813,11 @@ def add_cpu(self, name="vexriscv", variant="standard", cls=None, reset_address=N
                 for name, loc in self.cpu.interrupts.items():
                     self.irq.add(name, loc)
                 self.add_config("CPU_HAS_INTERRUPT")
+
+
             if hasattr(self, "ctrl"):
-                self.comb += self.cpu.reset.eq(self.ctrl.reset)
+                if hasattr(self.ctrl, "reset"):
+                    self.comb += self.cpu.reset.eq(self.ctrl.reset)
             self.add_config("CPU_RESET_ADDR", reset_address)
         # Add constants
         self.add_config("CPU_TYPE",    str(name))
@@ -838,7 +860,8 @@ def do_finalize(self):
                     register       = True,
                     timeout_cycles = self.bus.timeout)
                 if hasattr(self, "ctrl") and self.bus.timeout is not None:
-                    self.comb += self.ctrl.bus_error.eq(self.bus_interconnect.timeout.error)
+                    if hasattr(self.ctrl, "bus_error"):
+                        self.comb += self.ctrl.bus_error.eq(self.bus_interconnect.timeout.error)
             self.bus.logger.info("Interconnect: {} ({} <-> {}).".format(
                 colorer(self.bus_interconnect.__class__.__name__),
                 colorer(len(self.bus.masters)),

litex/soc/integration/soc_core.py

@@ -97,6 +97,7 @@ def __init__(self, platform, clk_freq,
         with_timer               = True,
         # Controller parameters
         with_ctrl                = True,
+        ctrl_uptime              = False,
         # Others
         **kwargs):
 
@@ -146,7 +147,7 @@ def __init__(self, platform, clk_freq,
 
         # Add SoCController
         if with_ctrl:
-            self.add_controller("ctrl")
+            self.add_controller("ctrl", with_uptime=ctrl_uptime)
 
         # Add CPU
         self.add_cpu(

litex/soc/software/bios/boot.c

@@ -217,7 +217,7 @@ int serialboot(void)
 				break;
 			}
 			case SFL_CMD_REBOOT:
-#ifdef CSR_CTRL_BASE
+#ifdef CSR_CTRL_RESET_ADDR
 				uart_write(SFL_ACK_SUCCESS);
 				ctrl_reset_write(1);
 #endif

litex/soc/software/bios/commands/cmd_bios.c

@@ -61,7 +61,7 @@ define_command(ident, ident_helper, "Display identifier", SYSTEM_CMDS);
  * Reboot the system
  *
  */
-#ifdef CSR_CTRL_BASE
+#ifdef CSR_CTRL_RESET_ADDR
 static void reboot(int nb_params, char **params)
 {
 	ctrl_reset_write(1);