From e695cb91ab0ddc099a19c690f89c99b609c6a404 Mon Sep 17 00:00:00 2001
From: Stephen Crane <jscrane@gmail.com>
Date: Tue, 21 Oct 2014 19:41:44 +0100
Subject: [PATCH] checkpointing

---
 cpu.h         |  5 ++++-
 hardware.cpp  | 30 +++++++++++++++++++++++++++++-
 hardware.h    |  4 +++-
 memory.cpp    | 22 ++++++++++------------
 memory.h      |  6 +++++-
 ram.h         |  2 +-
 spiram.h      |  2 +-
 utftdisplay.h |  2 +-
 8 files changed, 54 insertions(+), 19 deletions(-)

diff --git a/cpu.h b/cpu.h
index 4d41e47..2e92061 100644
--- a/cpu.h
+++ b/cpu.h
@@ -8,7 +8,7 @@
 #include <setjmp.h>
 #endif
 
-class CPU {
+class CPU: public Checkpointable {
 public:
 	virtual void reset () =0;
 	virtual Memory::address run (unsigned instructions) =0;
@@ -17,6 +17,9 @@ public:
 
 	typedef void (*statfn) (const char *, ...);
 
+	virtual void checkpoint(Stream &s) = 0;
+	virtual void restore(Stream &s) = 0;
+
 protected:
 	CPU (Memory *m, jmp_buf *e, statfn s): _memory(m), _err(e), _status(s){}
 	Memory *_memory;
diff --git a/hardware.cpp b/hardware.cpp
index 4daac86..930fcd7 100644
--- a/hardware.cpp
+++ b/hardware.cpp
@@ -5,14 +5,17 @@
 #include "memory.h"
 #include "spiram.h"
 
+#include "cpu.h"
 #include "hardware.h"
 
 Memory memory;
 PS2Driver ps2;
 spiram sram(SPIRAM_SIZE);
 UTFT utft(TFT_MODEL, TFT_RS, TFT_WR, TFT_CS, TFT_RST);
+static CPU *_cpu;
 
-bool hardware_init() {
+bool hardware_init(CPU &cpu) {
+	_cpu = &cpu;
 	ps2.begin(KBD_DATA, KBD_IRQ);
 
 	pinMode(SD_CS, OUTPUT);
@@ -28,5 +31,30 @@ bool hardware_init() {
 
 	sram.begin(SPIRAM_CS, SPIRAM_SPI);
  
+	cpu.reset();
 	return sd;
 }
+
+void hardware_checkpoint(Stream &s) {
+	_cpu->checkpoint(s);
+	Memory::Device *d = 0;
+	for (unsigned i = 0; i < 0x10000; i += Memory::page_size) {
+		Memory::Device *dev = memory.get(i);
+		if (dev && dev != d) {
+			d = dev;
+			d->checkpoint(s);
+		}
+	}
+}
+
+void hardware_restore(Stream &s) {
+	_cpu->restore(s);
+	Memory::Device *d = 0;
+	for (unsigned i = 0; i < 0x10000; i += Memory::page_size) {
+		Memory::Device *dev = memory.get(i);
+		if (dev && dev != d) {
+			d = dev;
+			d->restore(s);
+		}
+	}
+}
diff --git a/hardware.h b/hardware.h
index dafe411..15c316c 100644
--- a/hardware.h
+++ b/hardware.h
@@ -32,7 +32,9 @@
 #define SD_CS		PF_3
 #define SD_SPI		1
 
-bool hardware_init(void);
+bool hardware_init(class CPU &);
+void hardware_checkpoint(Stream &);	// FIXME: make a path?
+void hardware_restore(Stream &);
 
 extern class PS2Driver ps2;
 extern class spiram sram;
diff --git a/memory.cpp b/memory.cpp
index f5395fc..6ccc260 100644
--- a/memory.cpp
+++ b/memory.cpp
@@ -1,24 +1,22 @@
 #include "memory.h"
 
 void Memory::put (Device &dev, address b) {
-  Device **d = _pages + b/page_size;
+	Device **d = _pages + b/page_size;
 
-  int size = dev.pages();
-  while (size--)
-    *d++ = &dev;
+	int size = dev.pages();
+	while (size--)
+		*d++ = &dev;
 
-  dev.base(b);
+	dev.base(b);
 }
 
 class NullDevice: public Memory::Device {
-  public:
-    NullDevice(): Memory::Device(65536) {}
-    void operator= (byte b) {}
-    operator byte() { return 0; }
+public:
+	NullDevice(): Memory::Device(65536) {}
+	void operator= (byte b) {}
+	operator byte() { return 0; }
 } nd;
 
 Memory::Memory() {
-  put(nd, 0);
+	put(nd, 0);
 }
-  
-    
diff --git a/memory.h b/memory.h
index 1b87d91..0da0065 100644
--- a/memory.h
+++ b/memory.h
@@ -19,10 +19,11 @@ public:
 	typedef unsigned short address;
 	static const int page_size = 256;
 
-	class Device {
+	class Device: public Checkpointable {
 	public:
 		Device (int bytes): _pages(bytes/page_size) {}
 		virtual ~Device () {}
+
 		int pages () const { return _pages; }
 		void access (address a) { _acc=a-_base; }
 		void base (address a) { _base=a; }
@@ -31,6 +32,9 @@ public:
 		virtual void operator= (byte) =0;
 		virtual operator byte () =0;
 
+		virtual void checkpoint(Stream &s) {};
+		virtual void restore(Stream &s) {};
+
 	protected:
 		address _acc, _base;
 	private:
diff --git a/ram.h b/ram.h
index 2c18d18..49c61d9 100644
--- a/ram.h
+++ b/ram.h
@@ -1,7 +1,7 @@
 #ifndef _RAM_H
 #define _RAM_H
 
-class ram: public Memory::Device, public Checkpointable {
+class ram: public Memory::Device {
 public:
 	virtual void operator= (byte c) { _mem[_acc] = c; }
 	virtual operator byte () { return _mem[_acc]; }
diff --git a/spiram.h b/spiram.h
index 82783ab..4314bca 100644
--- a/spiram.h
+++ b/spiram.h
@@ -1,7 +1,7 @@
 #ifndef __SPIRAM_H__
 #define __SPIRAM_H__
 
-class spiram: public Memory::Device, public Checkpointable {
+class spiram: public Memory::Device {
 public:
 	virtual void operator= (byte c);
 	virtual operator byte ();
diff --git a/utftdisplay.h b/utftdisplay.h
index 9b164a3..9df2593 100644
--- a/utftdisplay.h
+++ b/utftdisplay.h
@@ -3,7 +3,7 @@
 
 class Stream;
 
-class UTFTDisplay: public Memory::Device, public Checkpointable {
+class UTFTDisplay: public Memory::Device {
 public:
 	void begin(unsigned bg, unsigned fg);
 	void clear();