From 9921f1c974f0b0d7cbe585b39852b14b389eaa0f Mon Sep 17 00:00:00 2001
From: Michel Heily <michelheily@gmail.com>
Date: Tue, 25 Jun 2019 05:16:14 +0300
Subject: [PATCH] Add info and reset commands

---
 src/arm7tdmi/cpu.rs | 16 +++++++++++++++-
 src/debugger.rs     | 23 ++++++++++++++++++++++-
 2 files changed, 37 insertions(+), 2 deletions(-)

diff --git a/src/arm7tdmi/cpu.rs b/src/arm7tdmi/cpu.rs
index 06b455a..ea1b8fe 100644
--- a/src/arm7tdmi/cpu.rs
+++ b/src/arm7tdmi/cpu.rs
@@ -1,3 +1,5 @@
+use std::convert::TryFrom;
+
 use crate::num_traits::FromPrimitive;
 
 use super::arm::*;
@@ -5,9 +7,16 @@ use super::sysbus::SysBus;
 
 #[derive(Debug, PartialEq)]
 pub enum CpuError {
+    ArmDecodeError(ArmDecodeError),
     IllegalInstruction,
 }
 
+impl From<ArmDecodeError> for CpuError {
+    fn from(e: ArmDecodeError) -> CpuError {
+        CpuError::ArmDecodeError(e)
+    }
+}
+
 pub type CpuResult<T> = Result<T, CpuError>;
 
 #[derive(Debug, PartialEq)]
@@ -92,7 +101,12 @@ impl Core {
     }
 
     fn step_arm(&mut self, sysbus: &mut SysBus) -> CpuResult<()> {
-        Err(CpuError::IllegalInstruction)
+        // fetch
+        let insn = sysbus.read_32(self.pc);
+        // decode
+        let insn = ArmInstruction::try_from((insn, self.pc))?;
+        
+        Ok(())
     }
 
     pub fn step(&mut self, sysbus: &mut SysBus) -> CpuResult<()> {
diff --git a/src/debugger.rs b/src/debugger.rs
index 07348ea..0aa26f8 100644
--- a/src/debugger.rs
+++ b/src/debugger.rs
@@ -26,9 +26,16 @@ pub struct Debugger {
 #[derive(Debug, PartialEq)]
 pub enum DebuggerError {
     ParsingError(String),
+    CpuError(cpu::CpuError),
     InvalidCommand(String)
 }
 
+impl From<cpu::CpuError> for DebuggerError {
+    fn from(e: cpu::CpuError) -> DebuggerError {
+        DebuggerError::CpuError(e)
+    }
+}
+
 impl From<nom::Err<(&str, nom::error::ErrorKind)>> for DebuggerError {
     fn from(e: nom::Err<(&str, nom::error::ErrorKind)>) -> DebuggerError {
         DebuggerError::ParsingError("parsing of command failed".to_string())
@@ -39,11 +46,13 @@ type DebuggerResult<T> = Result<T, DebuggerError>;
 
 #[derive(Debug, PartialEq)]
 enum DebuggerCommand {
+    Info,
     SingleStep,
     Continue,
     Disass { addr: u32, num_opcodes: usize },
     AddBreakpoint(u32),
     ListBreakpoints,
+    Reset,
     Quit,
     Nop,
 }
@@ -79,6 +88,7 @@ fn parse_debugger_command(input: &str) -> DebuggerResult<DebuggerCommand> {
     // TODO this code is shit!
     let (input, command_name) = parse_word(input)?;
     match command_name {
+        "i" | "info" => Ok(Info),
         "s" | "step" => Ok(SingleStep),
         "c" | "continue" => Ok(Continue),
         "d" | "disass" => {
@@ -96,6 +106,7 @@ fn parse_debugger_command(input: &str) -> DebuggerResult<DebuggerCommand> {
         }
         "bl" => Ok(ListBreakpoints),
         "q" | "quit" => Ok(Quit),
+        "r" | "reset" => Ok(Reset),
         "" => Ok(Nop),
         _ => Err(DebuggerError::InvalidCommand(command_name.to_string()))
     }
@@ -119,8 +130,13 @@ impl Debugger {
                     let command = parse_debugger_command(&line);
                     match command {
                         Ok(Nop) => (),
+                        Ok(Info) => {
+                            println!("cpu info: {:#?}", self.cpu)
+                        }
                         Ok(SingleStep) => {
-                            self.cpu.step(&mut self.sysbus).unwrap()
+                            println!("single step:");
+                            self.cpu.step(&mut self.sysbus)?;
+                            ()
                         },
                         Ok(Quit) => {
                             print!("Quitting!");
@@ -141,6 +157,11 @@ impl Debugger {
                                 println!("[{}] 0x{:08x}", i, b)
                             }
                         }
+                        Ok(Reset) => {
+                            println!("resetting cpu...");
+                            self.cpu.reset();
+                            println!("cpu is restarted!")
+                        }
                         Err(DebuggerError::InvalidCommand(command)) => {
                             println!("invalid command: {}", command)
                         }