From e6c6f0462e72bbb34c0c055649cae87a5fb49d9c Mon Sep 17 00:00:00 2001
From: Donald Sebastian Leung
Date: Thu, 30 Jul 2020 13:48:01 +0800
Subject: [PATCH] Add I-type instruction format
---
insns/insn_I_type.py | 37 +++++++++++++++++++++++++++++++++++++
1 file changed, 37 insertions(+)
create mode 100644 insns/insn_I_type.py
diff --git a/insns/insn_I_type.py b/insns/insn_I_type.py
new file mode 100644
index 0000000..1ecf805
--- /dev/null
+++ b/insns/insn_I_type.py
@@ -0,0 +1,37 @@
+from insn_general import *
+
+class rvfi_insn_I_type(rvfi_insn_general):
+ def __init__(self, RISCV_FORMAL_ILEN=32, RISCV_FORMAL_XLEN=32):
+ super(rvfi_insn_I_type, self).__init__(RISCV_FORMAL_ILEN, RISCV_FORMAL_XLEN)
+ self.insn_padding = Signal(self.RISCV_FORMAL_ILEN)
+ self.insn_imm = Signal(self.RISCV_FORMAL_XLEN)
+ self.insn_rs1 = Signal(5)
+ self.insn_funct3 = Signal(3)
+ self.insn_rd = Signal(5)
+ self.insn_opcode = Signal(7)
+ self.misa_ok = Signal(1)
+ self.ialign16 = Signal(1)
+ def ports(self):
+ return super(rvfi_insn_I_type, self).ports()
+ def elaborate(self, platform):
+ m = super(rvfi_insn_I_type, self).elaborate(platform)
+
+ # I-type instruction format
+ m.d.comb += self.insn_padding.eq(self.rvfi_insn >> 32)
+ m.d.comb += self.insn_imm.eq(Value.as_signed(self.rvfi_insn[20:32]))
+ m.d.comb += self.insn_rs1.eq(self.rvfi_insn[15:20])
+ m.d.comb += self.insn_funct3.eq(self.rvfi_insn[12:15])
+ m.d.comb += self.insn_rd.eq(self.rvfi_insn[7:12])
+ m.d.comb += self.insn_opcode.eq(self.rvfi_insn[:7])
+
+ m.d.comb += self.misa_ok.eq(1)
+ m.d.comb += self.ialign16.eq(0)
+
+ # default assignments
+ m.d.comb += self.spec_rs2_addr.eq(0)
+ m.d.comb += self.spec_mem_addr.eq(0)
+ m.d.comb += self.spec_mem_rmask.eq(0)
+ m.d.comb += self.spec_mem_wmask.eq(0)
+ m.d.comb += self.spec_mem_wdata.eq(0)
+
+ return m