From 0ae0e9c356418eb7a6673e25f26c2550c991d7da Mon Sep 17 00:00:00 2001
From: Donald Sebastian Leung <dl@m-labs.hk>
Date: Mon, 27 Jul 2020 15:31:46 +0800
Subject: [PATCH] Add rvfi_dmem_check

---
 checks/rvfi_dmem_check.py | 82 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 82 insertions(+)
 create mode 100644 checks/rvfi_dmem_check.py

diff --git a/checks/rvfi_dmem_check.py b/checks/rvfi_dmem_check.py
new file mode 100644
index 0000000..4444ed7
--- /dev/null
+++ b/checks/rvfi_dmem_check.py
@@ -0,0 +1,82 @@
+from nmigen import *
+from nmigen.hdl.ast import *
+
+class rvfi_dmem_check(Elaboratable):
+    def __init__(self, RISCV_FORMAL_ILEN=32, RISCV_FORMAL_XLEN=32):
+        self.RISCV_FORMAL_ILEN = RISCV_FORMAL_ILEN
+        self.RISCV_FORMAL_XLEN = RISCV_FORMAL_XLEN
+        self.reset = Signal(1)
+        self.enable = Signal(1)
+        self.dmem_addr = Signal(self.RISCV_FORMAL_XLEN)
+        self.rvfi_valid = Signal(1)
+        self.rvfi_order = Signal(64)
+        self.rvfi_insn = Signal(self.RISCV_FORMAL_ILEN)
+        self.rvfi_trap = Signal(1)
+        self.rvfi_halt = Signal(1)
+        self.rvfi_intr = Signal(1)
+        self.rvfi_mode = Signal(2)
+        self.rvfi_ixl = Signal(2)
+        self.rvfi_rs1_addr = Signal(5)
+        self.rvfi_rs2_addr = Signal(5)
+        self.rvfi_rs1_rdata = Signal(self.RISCV_FORMAL_XLEN)
+        self.rvfi_rs2_rdata = Signal(self.RISCV_FORMAL_XLEN)
+        self.rvfi_rd_addr = Signal(5)
+        self.rvfi_rd_wdata = Signal(self.RISCV_FORMAL_XLEN)
+        self.rvfi_pc_rdata = Signal(self.RISCV_FORMAL_XLEN)
+        self.rvfi_pc_wdata = Signal(self.RISCV_FORMAL_XLEN)
+        self.rvfi_mem_addr = Signal(self.RISCV_FORMAL_XLEN)
+        self.rvfi_mem_rmask = Signal(int(self.RISCV_FORMAL_XLEN // 8))
+        self.rvfi_mem_wmask = Signal(int(self.RISCV_FORMAL_XLEN // 8))
+        self.rvfi_mem_rdata = Signal(self.RISCV_FORMAL_XLEN)
+        self.rvfi_mem_wdata = Signal(self.RISCV_FORMAL_XLEN)
+    def ports(self):
+        input_ports = [
+            self.reset,
+            self.enable,
+            self.rvfi_valid,
+            self.rvfi_order,
+            self.rvfi_insn,
+            self.rvfi_trap,
+            self.rvfi_halt,
+            self.rvfi_intr,
+            self.rvfi_mode,
+            self.rvfi_ixl,
+            self.rvfi_rs1_addr,
+            self.rvfi_rs2_addr,
+            self.rvfi_rs1_rdata,
+            self.rvfi_rs2_rdata,
+            self.rvfi_rd_addr,
+            self.rvfi_rd_wdata,
+            self.rvfi_pc_rdata,
+            self.rvfi_pc_wdata,
+            self.rvfi_mem_addr,
+            self.rvfi_mem_rmask,
+            self.rvfi_mem_wmask,
+            self.rvfi_mem_rdata,
+            self.rvfi_mem_wdata
+        ]
+        output_ports = [
+            self.dmem_addr
+        ]
+        return input_ports + output_ports
+    def elaborate(self, platform):
+        m = Module()
+
+        dmem_addr_randval = AnyConst(self.RISCV_FORMAL_XLEN)
+        m.d.comb += self.dmem_addr.eq(dmem_addr_randval)
+
+        dmem_shadow = Signal(self.RISCV_FORMAL_XLEN)
+        dmem_written = Signal(int(self.RISCV_FORMAL_XLEN // 8), reset=0)
+
+        with m.If(self.reset):
+            m.d.sync += dmem_written.eq(0)
+        with m.Else():
+            with m.If(self.rvfi_valid & (self.rvfi_mem_addr == self.dmem_addr) & 1):
+                for i in range(int(self.RISCV_FORMAL_XLEN // 8)):
+                    with m.If(self.enable & self.rvfi_mem_rmask[i] & dmem_written[i]):
+                        m.d.comb += Assert(dmem_shadow[i*8:i*8+8] == self.rvfi_mem_rdata[i*8:i*8+8])
+                    with m.If(self.rvfi_mem_wmask[i]):
+                        m.d.sync += dmem_shadow[i*8:i*8+8].eq(self.rvfi_mem_wdata[i*8:i*8+8])
+                        m.d.sync += dmem_written[i].eq(1)
+
+        return m