From 20a011a07484fef62feff95e96f7835663d90e32 Mon Sep 17 00:00:00 2001
From: Connor McLaughlin <mclaughc@outlook.com>
Date: Sat, 5 Oct 2019 16:07:15 +1000
Subject: [PATCH] CDROM: Improve timings

---
 src/core/cdrom.cpp | 44 +++++++++++++++++++++++---------------------
 src/core/cdrom.h   |  6 ++++--
 2 files changed, 27 insertions(+), 23 deletions(-)

diff --git a/src/core/cdrom.cpp b/src/core/cdrom.cpp
index df23476c8..187fe55a2 100644
--- a/src/core/cdrom.cpp
+++ b/src/core/cdrom.cpp
@@ -19,6 +19,14 @@ bool CDROM::Initialize(System* system, DMA* dma, InterruptController* interrupt_
 }
 
 void CDROM::Reset()
+{
+  if (m_media)
+    m_media->Seek(0);
+
+  SoftReset();
+}
+
+void CDROM::SoftReset()
 {
   m_command_state = CommandState::Idle;
   m_command = Command::Sync;
@@ -36,6 +44,7 @@ void CDROM::Reset()
   m_param_fifo.Clear();
   m_response_fifo.Clear();
   m_data_fifo.Clear();
+  m_sector_buffer.clear();
   UpdateStatusRegister();
 }
 
@@ -379,23 +388,13 @@ void CDROM::UpdateStatusRegister()
   m_status.BUSYSTS = m_command_state == CommandState::WaitForExecute;
 }
 
-u32 CDROM::GetTicksForCommand() const
+u32 CDROM::GetAckDelayForCommand() const
 {
-  switch (m_command)
-  {
-    case Command::ReadN:
-    case Command::ReadS:
-    {
-      // more if seeking..
-      return 1000;
-    }
-
-    case Command::Pause:
-      return 1000;
-
-    default:
-      return 1000;
-  }
+  const u32 default_ack_delay = 20000;
+  if (m_command == Command::Init)
+    return 60000;
+  else
+    return default_ack_delay;
 }
 
 u32 CDROM::GetTicksForRead() const
@@ -443,7 +442,7 @@ void CDROM::BeginCommand(Command command)
 
   m_command = command;
   m_command_stage = 0;
-  m_command_remaining_ticks = GetTicksForCommand();
+  m_command_remaining_ticks = GetAckDelayForCommand();
   if (m_command_remaining_ticks == 0)
   {
     ExecuteCommand();
@@ -524,7 +523,7 @@ void CDROM::ExecuteCommand()
           // INT3(stat), ...
           m_response_fifo.Push(m_secondary_status.bits);
           SetInterrupt(Interrupt::ACK);
-          NextCommandStage(true, GetTicksForCommand());
+          NextCommandStage(true, 18000);
         }
       }
       else
@@ -574,7 +573,7 @@ void CDROM::ExecuteCommand()
         m_secondary_status.seeking = true;
         m_response_fifo.Push(m_secondary_status.bits);
         SetInterrupt(Interrupt::ACK);
-        NextCommandStage(false, 100);
+        NextCommandStage(false, 20000);
       }
       else
       {
@@ -640,7 +639,7 @@ void CDROM::ExecuteCommand()
         m_response_fifo.Push(m_secondary_status.bits);
         SetInterrupt(Interrupt::ACK);
         StopReading();
-        NextCommandStage(true, was_reading ? (m_mode.double_speed ? 2000000 : 1000000) : 1000);
+        NextCommandStage(true, was_reading ? (m_mode.double_speed ? 2000000 : 1000000) : 7000);
       }
       else
       {
@@ -660,10 +659,13 @@ void CDROM::ExecuteCommand()
         m_response_fifo.Push(m_secondary_status.bits);
         SetInterrupt(Interrupt::ACK);
         StopReading();
-        NextCommandStage(true, 1000);
+        NextCommandStage(true, 8000);
       }
       else
       {
+        m_mode.bits = 0;
+        m_secondary_status.bits = 0;
+        m_secondary_status.motor_on = true;
         m_response_fifo.Push(m_secondary_status.bits);
         SetInterrupt(Interrupt::INT2);
         EndCommand();
diff --git a/src/core/cdrom.h b/src/core/cdrom.h
index 6bd91652e..021323ab8 100644
--- a/src/core/cdrom.h
+++ b/src/core/cdrom.h
@@ -1,7 +1,7 @@
 #pragma once
 #include "common/bitfield.h"
-#include "common/fifo_queue.h"
 #include "common/cd_image.h"
+#include "common/fifo_queue.h"
 #include "types.h"
 #include <string>
 #include <vector>
@@ -154,12 +154,14 @@ private:
     BitField<u8, bool, 7, 1> BFRD;
   };
 
+  void SoftReset();
+
   bool HasPendingInterrupt() const { return m_interrupt_flag_register != 0; }
   void SetInterrupt(Interrupt interrupt);
   void PushStatResponse(Interrupt interrupt = Interrupt::ACK);
   void UpdateStatusRegister();
 
-  u32 GetTicksForCommand() const;
+  u32 GetAckDelayForCommand() const;
   u32 GetTicksForRead() const;
   void BeginCommand(Command command); // also update status register
   void NextCommandStage(bool wait_for_irq, u32 time);