From d1a2cb9f4852bd8118cb4db043e6622cae077830 Mon Sep 17 00:00:00 2001
From: Luke Kenneth Casson Leighton <lkcl@lkcl.net>
Date: Fri, 15 May 2020 19:58:47 +0100
Subject: [PATCH] add branch input record

---
 libreriscv                        |  2 +-
 src/soc/branch/br_input_record.py | 84 +++++++++++++++++++++++++++++++
 2 files changed, 85 insertions(+), 1 deletion(-)
 create mode 100644 src/soc/branch/br_input_record.py

diff --git a/libreriscv b/libreriscv
index 2d8ae9db..f7602e59 160000
--- a/libreriscv
+++ b/libreriscv
@@ -1 +1 @@
-Subproject commit 2d8ae9db6019c3a7ed881f14612f2b66bb263a9e
+Subproject commit f7602e599e6557e45249b80d888631a9cf241cb7
diff --git a/src/soc/branch/br_input_record.py b/src/soc/branch/br_input_record.py
new file mode 100644
index 00000000..cca2e74f
--- /dev/null
+++ b/src/soc/branch/br_input_record.py
@@ -0,0 +1,84 @@
+from nmigen.hdl.rec import Record, Layout
+
+from soc.decoder.power_enums import InternalOp, Function, CryIn
+
+
+class CompBROpSubset(Record):
+    """CompBROpSubset
+
+    TODO: remove anything not needed by the Branch pipeline (determine this
+    after all branch operations have been written.  see
+    https://bugs.libre-soc.org/show_bug.cgi?id=313#c3)
+
+    a copy of the relevant subset information from Decode2Execute1Type
+    needed for Branch operations.  use with eq_from_execute1 (below) to
+    grab subsets.
+    """
+    def __init__(self, name=None):
+        layout = (('insn_type', InternalOp),
+                  ('fn_unit', Function),
+                  ('imm_data', Layout((("imm", 64), ("imm_ok", 1)))),
+                    #'cr = Signal(32, reset_less=True) # NO: this is from the CR SPR
+                    #'xerc = XerBits() # NO: this is from the XER SPR
+                  ('lk', 1),
+                  ('rc', Layout((("rc", 1), ("rc_ok", 1)))),
+                  ('oe', Layout((("oe", 1), ("oe_ok", 1)))),
+                  ('invert_a', 1),
+                  ('invert_out', 1),
+                  ('input_carry', CryIn),
+                  ('output_carry', 1),
+                  ('input_cr', 1),
+                  ('output_cr', 1),
+                  ('is_32bit', 1),
+                  ('is_signed', 1),
+                  ('data_len', 4), # TODO: should be in separate CompLDSTSubset
+                  ('insn', 32),
+                  ('byte_reverse', 1),
+                  ('sign_extend', 1))
+
+        Record.__init__(self, Layout(layout), name=name)
+
+        # grrr.  Record does not have kwargs
+        self.insn_type.reset_less = True
+        self.fn_unit.reset_less = True
+        #self.cr = Signal(32, reset_less = True
+        #self.xerc = XerBits(
+        self.lk.reset_less = True
+        self.invert_a.reset_less = True
+        self.invert_out.reset_less = True
+        self.input_carry.reset_less = True
+        self.output_carry.reset_less = True
+        self.input_cr.reset_less = True
+        self.output_cr.reset_less = True
+        self.is_32bit.reset_less = True
+        self.is_signed.reset_less = True
+        self.data_len.reset_less = True
+        self.byte_reverse.reset_less = True
+        self.sign_extend.reset_less = True
+
+    def eq_from_execute1(self, other):
+        """ use this to copy in from Decode2Execute1Type
+        """
+        res = []
+        for fname, sig in self.fields.items():
+            eqfrom = other.fields[fname]
+            res.append(sig.eq(eqfrom))
+        return res
+
+    def ports(self):
+        return [self.insn_type,
+                #self.cr,
+                #self.xerc,
+                self.lk,
+                self.invert_a,
+                self.invert_out,
+                self.input_carry,
+                self.output_carry,
+                self.input_cr,
+                self.output_cr,
+                self.is_32bit,
+                self.is_signed,
+                self.data_len,
+                self.byte_reverse,
+                self.sign_extend,
+        ]
-- 
2.30.2