Finish NVRAM implementation.

devices/heathrow.cpp

@@ -7,7 +7,6 @@
 
 #include <cinttypes>
 #include <iostream>
-#include <cassert>
 #include "macio.h"
 #include "viacuda.h"
 
@@ -21,13 +20,14 @@ using namespace std;
 HeathrowIC::HeathrowIC() : PCIDevice("mac-io/heathrow")
 {
     this->viacuda = new ViaCuda();
-    this->nvram = new NVram();
-    assert(this->viacuda); // FIXME: do proper exception handling!
-    assert(this->nvram); // FIXME: do proper exception handling!
+    this->nvram   = new NVram();
 }
 
 HeathrowIC::~HeathrowIC()
 {
+    if (this->nvram)
+        delete(this->nvram);
+
     if (this->viacuda)
         delete(this->viacuda);
 }
@@ -83,6 +83,9 @@ uint32_t HeathrowIC::read(uint32_t offset, int size)
     case 0x17:
         res = this->viacuda->read((offset - 0x16000) >> 9);
         break;
+    case 0x60:
+    case 0x70:
+        res = this->nvram->read_byte((offset - 0x60000) >> 4);
     default:
         cout << "unmapped I/O space: " << sub_dev << endl;
     }

devices/nvram.cpp

@@ -10,60 +10,70 @@
 #include <cinttypes>
 #include "nvram.h"
 
+/** @file Non-volatile RAM implementation.
+ */
+
 using namespace std;
 
+/** the signature for NVRAM backing file identification. */
+static char NVRAM_FILE_ID[] = "DINGUSPPCNVRAM";
 
-NVram::NVram()
+NVram::NVram(std::string file_name, uint32_t ram_size)
 {
-    this->nvram_init();
+    this->file_name = file_name;
+    this->ram_size  = ram_size;
+
+    this->storage = new uint8_t[ram_size];
+
+    this->init();
 }
 
 NVram::~NVram()
 {
-    this->nvram_save();
+    this->save();
+    if (this->storage)
+        delete this->storage;
 }
 
-void NVram::nvram_init() {
-    NVram::nvram_file.open("nvram.bin", ios::in | ios::out | ios::binary);
+uint8_t NVram::read_byte(uint32_t offset)
+{
+    return (this->storage[offset]);
+}
 
-    if (nvram_file.fail()) {
-        std::cout << "Warning: Could not find the NVRAM file. This will be blank. \n" << endl;
-        NVram::nvram_file.write(0x00, 8192);
-        return;
-    }
+void NVram::write_byte(uint32_t offset, uint8_t val)
+{
+    this->storage[offset] = val;
+}
 
-    NVram::nvram_file.seekg(0, nvram_file.end);
-    NVram::nvram_filesize = nvram_file.tellg();
-    NVram::nvram_file.seekg(0, nvram_file.beg);
+void NVram::init() {
+    char     sig[sizeof(NVRAM_FILE_ID)];
+    uint16_t data_size;
 
-    if (NVram::nvram_filesize != 0x2000) {
-        NVram::nvram_file.write(0x00, 8192);
-    }
+    ifstream f(this->file_name, ios::in | ios::binary);
 
-    char temp_storage[8192];
-
-    NVram::nvram_file.read(temp_storage, 8192);
-
-    //hack copying to the NVRAM Array GO!
-    for (int i = 0; i < 8192; i++)
+    if (f.fail() || !f.read(sig, sizeof(NVRAM_FILE_ID))   ||
+        !f.read((char *)&data_size, sizeof(data_size))    ||
+        memcmp(sig, NVRAM_FILE_ID, sizeof(NVRAM_FILE_ID)) ||
+        data_size != this->ram_size                       ||
+        !f.read((char *)this->storage, this->ram_size))
     {
-        NVram::nvram_storage[i] = (uint8_t) temp_storage[i];
+        cout << "WARN: Could not restore NVRAM content from the given file." << endl;
+        memset(this->storage, 0, sizeof(this->ram_size));
     }
+
+    f.close();
 }
 
-void NVram::nvram_save() {
-    NVram::nvram_savefile.open("nvram.bin", ios::out | ios::binary);
+void NVram::save()
+{
+    ofstream f(this->file_name, ios::out | ios::binary);
 
-    NVram::nvram_savefile.write((char*)nvram_storage, 8192);
+    /* write file identification */
+    f.write(NVRAM_FILE_ID, sizeof(NVRAM_FILE_ID));
+    f.write((char *)&this->ram_size, sizeof(this->ram_size));
 
-    NVram::nvram_savefile.close();
+    /* write NVRAM content */
+    f.write((char *)this->storage, this->ram_size);
+
+    f.close();
 }
-
-uint8_t NVram::nvram_read(uint32_t nvram_offset){
-    nvram_value = NVram::nvram_storage[nvram_offset];
-    return nvram_value;
-}
-
-void NVram::nvram_write(uint32_t nvram_offset, uint8_t write_val){
-    NVram::nvram_storage[nvram_offset] = write_val;
-}

devices/nvram.h

@@ -1,33 +1,31 @@
 #ifndef NVRAM_H
 #define NVRAM_H
 
-#include <iostream>
-#include <fstream>
+#include <string>
 #include <cinttypes>
 
+/** @file Non-volatile RAM emulation.
+
+    It implements a non-volatile random access storage whose content will be
+    automatically saved to and restored from the dedicated file.
+ */
+
 class NVram
 {
 public:
-    NVram();
+    NVram(std::string file_name = "nvram.bin", uint32_t ram_size = 8192);
     ~NVram();
 
-    uint8_t read(int value);
-    void write(int reg, uint8_t value);
+    uint8_t read_byte(uint32_t offset);
+    void    write_byte(uint32_t offset, uint8_t value);
 
 private:
-    std::fstream nvram_file; //NVRAM file for storing and reading values
-    std::ofstream nvram_savefile; //Save file when closing out DingusPPC
+    std::string file_name; /* file name for the backing file. */
+    uint16_t    ram_size;  /* NVRAM size. */
+    uint8_t*    storage;
 
-    /* NVRAM state. */
-    uint32_t nvram_offset;
-    uint32_t nvram_filesize;
-    uint8_t nvram_value;
-    uint8_t nvram_storage[8192];
-
-    void nvram_init();
-    void nvram_save();
-    uint8_t nvram_read(uint32_t nvram_offset);
-    void nvram_write(uint32_t nvram_offset, uint8_t write_val);
+    void    init();
+    void    save();
 };
 
 #endif /* NVRAM_H */