From: Luke Kenneth Casson Leighton <lkcl@lkcl.net>
Date: Tue, 7 May 2019 02:53:47 +0000 (+0100)
Subject: add combined int/fp issue unit
X-Git-Tag: ls180-24jan2020~1008
X-Git-Url: https://git.libre-soc.org/?p=ieee754fpu.git;a=commitdiff_plain;h=de38a51b94b0848deb776a31dd3e25f9d615debf

add combined int/fp issue unit
---

diff --git a/src/scoreboard/issue_unit.py b/src/scoreboard/issue_unit.py
index 3506b9e3..d1f58d11 100644
--- a/src/scoreboard/issue_unit.py
+++ b/src/scoreboard/issue_unit.py
@@ -13,6 +13,7 @@ class IssueUnit(Elaboratable):
         Inputs
 
         * :wid:         register file width
+        * :n_insns:     number of instructions in this issue unit.
     """
     def __init__(self, wid, n_insns):
         self.reg_width = wid
@@ -76,6 +77,33 @@ class IssueUnit(Elaboratable):
         return list(self)
 
 
+class IntFPIssueUnit(Elaboratable):
+    def __init__(self, wid, n_int_insns, n_fp_insns):
+        self.i = IssueUnit(wid, n_int_insns)
+        self.f = IssueUnit(wid, n_fp_insns)
+        self.issue_o = Signal(reset_less=True)
+
+        # some renames
+        self.int_write_pending_i = self.i.g_wr_pend_i
+        self.fp_write_pending_i = self.f.g_wr_pend_i
+        self.int_write_pending_i.name = 'int_write_pending_i'
+        self.fp_write_pending_i.name = 'fp_write_pending_i'
+
+    def elaborate(self, platform):
+        m = Module()
+        m.submodules.intissue = self.i
+        m.submodules.fpissue = self.f
+
+        m.d.comb += self.issue_o.eq(self.i.g_issue_o | self.f.g_issue_o)
+
+        return m
+
+    def ports(self):
+        yield self.issue_o
+        yield from self.i
+        yield from self.f
+
+
 def issue_unit_sim(dut):
     yield dut.dest_i.eq(1)
     yield dut.issue_i.eq(1)
@@ -104,6 +132,11 @@ def test_issue_unit():
     with open("test_issue_unit.il", "w") as f:
         f.write(vl)
 
+    dut = IntFPIssueUnit(32, 3, 3)
+    vl = rtlil.convert(dut, ports=dut.ports())
+    with open("test_intfp_issue_unit.il", "w") as f:
+        f.write(vl)
+
     run_simulation(dut, issue_unit_sim(dut), vcd_name='test_issue_unit.vcd')
 
 if __name__ == '__main__':