1 files changed, 79 insertions, 5 deletions

diff --git a/config/config.py b/config/config.py
index 4648f9d..bf77a36 100755
--- a/config/config.py
+++ b/config/config.py
@@ -35,6 +35,11 @@ Generate core_selector.v for a set of cores.
 # still takes up more than one new core slot even if trng uses the old
 # scheme internally.  How many slots should we allocate, and what
 # addressing scheme is the trng core expecting to see?
+#
+# So perhaps a better plan would be to keep Paul's scheme and just
+# give modexps6 four core's worth of space, passing a 10 bit composite
+# address constructed in much the same way as the trng template
+# already does.
 
 # Unrelated: Timing delays.  Paul added extra registers to slow cores
 # other than modexps6 down by one clock cycle, to compensate for the
@@ -200,6 +205,10 @@ class TRNGCore(InvertedResetCore):
             n = subcore.assign_core_number(n)
         return n
 
+    @property
+    def last_subcore_upper_instance_name(self):
+        return self.subcores[-1].upper_instance_name
+
     def createInstance(self):
         return createInstance_template_TRNG.format(core = self)
 
@@ -209,6 +218,20 @@ class TRNGCore(InvertedResetCore):
     def createMux(self):
         return super(TRNGCore, self).createMux() + "".join(subcore.createMux() for subcore in self.subcores)
 
+
+class ModExpS6Core(Core):
+
+    def assign_core_number(self, n):
+        n = super(ModExpS6Core, self).assign_core_number(n)
+        return n + 3
+
+    def createInstance(self):
+        return createInstance_template_ModExpS6.format(core = self)
+
+    def createMux(self):
+        return createMux_modexps6_template.format(core = self)
+
+
 # Hook special classes in as handlers for the cores that require them.
 
 Core.special_class.update(
@@ -218,7 +241,8 @@ Core.special_class.update(
     sha1        = InvertedResetCore,
     sha256      = InvertedResetCore,
     sha512      = InvertedResetCore,
-    modexp      = InvertedResetCore)
+    modexp      = InvertedResetCore,
+    modexps6    = ModExpS6Core)
 
 
 # Templates (format strings), here instead of inline in the functions
@@ -255,6 +279,38 @@ createInstance_template_generic = """\
       .read_data(read_data_{core.instance_name})
       );
 
+   reg  [31: 0] read_data_{core.instance_name}_reg;
+   always @(posedge sys_clk)
+     read_data_{core.instance_name}_reg <= read_data_{core.instance_name};
+
+
+"""
+
+# Template used by ModExpS6Core.createInstance().  This is different
+# enough from the base template that it's easier to make this separate.
+
+createInstance_template_ModExpS6 = """\
+   //----------------------------------------------------------------
+   // {core.upper_instance_name}
+   //----------------------------------------------------------------
+   wire                 enable_{core.instance_name} = (addr_core_num >= CORE_ADDR_{core.upper_instance_name}) && (addr_core_num <= CORE_ADDR_{core.upper_instance_name} + 3);
+   wire [31: 0]         read_data_{core.instance_name};
+   wire                 error_{core.instance_name};
+   wire [1:0]           {core.instance_name}_prefix = addr_core_num[1:0] - CORE_ADDR_{core.upper_instance_name};
+
+   {core.name} {core.instance_name}_inst
+     (
+      .clk(sys_clk),
+      {core.reset_pin},
+
+      .cs(enable_{core.instance_name} & (sys_eim_rd | sys_eim_wr)),
+      .we(sys_eim_wr),
+
+      .address({{{core.instance_name}_prefix, addr_core_reg}}),
+      .write_data(sys_write_data),
+      .read_data(read_data_{core.instance_name})
+      );
+
 
 """
 
@@ -266,10 +322,10 @@ createInstance_template_TRNG = """\
    //----------------------------------------------------------------
    // {core.upper_instance_name}
    //----------------------------------------------------------------
-   wire                 enable_{core.instance_name} = (addr_core_num >= CORE_ADDR_TRNG) && (addr_core_num <= CORE_ADDR_TRNG_CSPRNG);
+   wire                 enable_{core.instance_name} = (addr_core_num >= CORE_ADDR_{core.upper_instance_name}) && (addr_core_num <= CORE_ADDR_{core.last_subcore_upper_instance_name});
    wire [31: 0]         read_data_{core.instance_name};
    wire                 error_{core.instance_name};
-   wire [3:0]           trng_prefix = addr_core_num[3:0] - CORE_ADDR_TRNG;
+   wire [3:0]           {core.instance_name}_prefix = addr_core_num[3:0] - CORE_ADDR_{core.upper_instance_name};
 
    {core.name} {core.instance_name}_inst
      (
@@ -279,7 +335,7 @@ createInstance_template_TRNG = """\
       .cs(enable_{core.instance_name} & (sys_eim_rd | sys_eim_wr)),
       .we(sys_eim_wr),
 
-      .address({{trng_prefix, addr_core_reg}}),
+      .address({{{core.instance_name}_prefix, addr_core_reg}}),
       .write_data(sys_write_data),
       .read_data(read_data_{core.instance_name}),
 
@@ -287,6 +343,10 @@ createInstance_template_TRNG = """\
       .debug(debug)
       );
 
+   reg  [31: 0] read_data_{core.instance_name}_reg;
+   always @(posedge sys_clk)
+     read_data_{core.instance_name}_reg <= read_data_{core.instance_name};
+
 
 """
 
@@ -295,11 +355,25 @@ createInstance_template_TRNG = """\
 createMux_template = """\
        CORE_ADDR_{core.upper_instance_name}:
          begin
-            sys_read_data_mux = read_data_{core0.instance_name};
+            sys_read_data_mux = read_data_{core0.instance_name}_reg;
             sys_error_mux = error_{core0.instance_name};
          end
 """
 
+# Template for ModExpS6.createMux() method.
+
+createMux_modexps6_template = """\
+       CORE_ADDR_{core.upper_instance_name} + 0,
+       CORE_ADDR_{core.upper_instance_name} + 1,
+       CORE_ADDR_{core.upper_instance_name} + 2,
+       CORE_ADDR_{core.upper_instance_name} + 3:
+         begin
+            sys_read_data_mux = read_data_{core.instance_name};
+            sys_error_mux = error_{core.instance_name};
+         end
+"""
+
+
 # Top-level (createModule) template.
 
 createModule_template = """\