From: Neel <neelgala@gmail.com>
Date: Sat, 14 Apr 2018 11:11:00 +0000 (+0530)
Subject: the assignment of a wire from an input configured pin must happen through individual... 
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=65ac2b19eb021bec3f5c6f2043e19d56a4ca5d7b;p=pinmux.git

the assignment of a wire from an input configured pin must happen through individual rules. The pinmuxing table might be defined such a way that input pins pin0 and pin2 drive the same function wrfunc. So pin0 using wrcell0_mux to assign wrfunc and pin2 uses wrcell2_mux to assign the same write again. Within the same rule this will cause a multi-driven issue. BSV takes care of this issue by generating an implicit priority between the rules. If rule-A is written before rule-B, then the effects of rule-B will be shadowed i.e only the output of rule-A will be visible.
---

diff --git a/src/bsv/actual_pinmux.py b/src/bsv/actual_pinmux.py
index 982cf46..374976f 100644
--- a/src/bsv/actual_pinmux.py
+++ b/src/bsv/actual_pinmux.py
@@ -10,8 +10,10 @@ except ImportError:
 # second argument is the mux value.
 # Third argument is the signal from the pinmap file
 mux_wire = '''
-        if(wrcell{0}_mux=={1})
-            {2}<=cell{0}_mux_in;'''
+      rule assign_{2}_on_cell{0}(wrcell{0}_mux=={1});
+        {2}<=cell{0}_mux_in;
+      endrule
+'''
 dedicated_wire = '''
       rule assign_{1}_on_cell{0};
         {1}<=cell{0}_mux_in;
@@ -45,13 +47,11 @@ def init(p, ifaces):
         p.pinmux += ";\n"
         # ======================================================== #
 
-    # check each cell if "peripheral input/inout" then assign its wire
-    # Here we check the direction of each signal in the dictionary.
-    # We choose to keep the dictionary within the code and not user-input
-    # since the interfaces are always standard and cannot change from
-    # user-to-user. Plus this also reduces human-error as well :)
-    p.pinmux += "      rule assign_inputs_from_io_to_wires;"
-    for cell in p.muxed_cells:
+        # check each cell if "peripheral input/inout" then assign its wire
+        # Here we check the direction of each signal in the dictionary.
+        # We choose to keep the dictionary within the code and not user-input
+        # since the interfaces are always standard and cannot change from
+        # user-to-user. Plus this also reduces human-error as well :)
         for i in range(0, len(cell) - 1):
             cname = cell[i + 1]
             temp = transfn(cname)
@@ -68,7 +68,6 @@ def init(p, ifaces):
                 p.pinmux += \
                     mux_wire.format(cell[0], i, "wr" + cname +
                                                 "_in") + "\n"
-    p.pinmux += "      endrule\n"
     # ============================================================ #
 
     # ==================  Logic for dedicated pins ========= #