src/soc/fu/branch/br_input_record.py

   1 from nmigen.hdl.rec import Record, Layout
   2
   3 from soc.decoder.power_enums import InternalOp, Function, CryIn
   4
   5
   6 class CompBROpSubset(Record):
   7     """CompBROpSubset
   8
   9     TODO: remove anything not needed by the Branch pipeline (determine this
  10     after all branch operations have been written.  see
  11     https://bugs.libre-soc.org/show_bug.cgi?id=313#c3)
  12
  13     a copy of the relevant subset information from Decode2Execute1Type
  14     needed for Branch operations.  use with eq_from_execute1 (below) to
  15     grab subsets.
  16     """
  17     def __init__(self, name=None):
  18         layout = (('insn_type', InternalOp),
  19                   ('fn_unit', Function),
  20                   ('imm_data', Layout((("imm", 64), ("imm_ok", 1)))),
  21                   ('lk', 1),
  22                   ('is_32bit', 1),
  23                   ('insn', 32),
  24                   )
  25
  26         Record.__init__(self, Layout(layout), name=name)
  27
  28         # grrr.  Record does not have kwargs
  29         self.insn_type.reset_less = True
  30         self.fn_unit.reset_less = True
  31         self.lk.reset_less = True
  32         self.is_32bit.reset_less = True
  33         self.insn.reset_less = True
  34
  35     def eq_from_execute1(self, other):
  36         """ use this to copy in from Decode2Execute1Type
  37         """
  38         res = []
  39         for fname, sig in self.fields.items():
  40             eqfrom = other.do.fields[fname]
  41             res.append(sig.eq(eqfrom))
  42         return res
  43
  44     def ports(self):
  45         return [self.insn_type,
  46                 self.fn_unit,
  47                 self.lk,
  48                 self.is_32bit,
  49                 self.insn,
  50         ]