modeling of a program ROM

assets/romtest.js

@@ -0,0 +1,2 @@
+sys.mapRom((exec_args[1]|0)||0);
+println(sys.romReadAll());

src/net/torvald/tsvm/AppLoader.java

@@ -4,6 +4,7 @@ import com.badlogic.gdx.Gdx;
 import com.badlogic.gdx.backends.lwjgl.LwjglApplication;
 import com.badlogic.gdx.backends.lwjgl.LwjglApplicationConfiguration;
 import com.badlogic.gdx.graphics.glutils.ShaderProgram;
+import net.torvald.tsvm.peripheral.GenericBios;
 
 public class AppLoader {
 
@@ -24,7 +25,10 @@ public class AppLoader {
         appConfig.width = 560;
         appConfig.height = 448;
 
-        new LwjglApplication(new VMGUI(appConfig), appConfig);
+
+        // val vm = VM(64.kB(), TheRealWorld(), arrayOf(GenericBios))
+        VM vm = new VM(64 << 10, new TheRealWorld(), new GenericBios[]{GenericBios.INSTANCE});
+        new LwjglApplication(new VMGUI(vm, appConfig), appConfig);
     }
 
     public static ShaderProgram loadShaderFromFile(String vert, String frag) {

src/net/torvald/tsvm/VM.kt

@@ -3,59 +3,22 @@ package net.torvald.tsvm
 import net.torvald.UnsafeHelper
 import net.torvald.UnsafePtr
 import net.torvald.tsvm.firmware.Firmware
-import net.torvald.tsvm.firmware.Firmware.Companion.toLuaValue
 import net.torvald.tsvm.peripheral.IOSpace
 import net.torvald.tsvm.peripheral.PeriBase
-import org.luaj.vm2.LuaValue
+import net.torvald.tsvm.peripheral.VMProgramRom
 import java.io.InputStream
 import java.io.OutputStream
-import java.io.PrintStream
 import java.util.*
 import kotlin.math.ceil
-import kotlin.random.Random
 
 /**
- * 1 byte = 2 pixels
- *
- * 560x448@4bpp = 125 440 bytes
- * 560x448@8bpp = 250 880 bytes
- *
- * -> 262144 bytes (256 kB)
- *
- * [USER AREA | HW AREA]
- *  Number of pheripherals = 8, of which the computer itself is considered as a peri.
- *
- * HW AREA = [Peripherals | MMIO | INTVEC]
- *
- * User area: 8 MB, hardware area: 8 MB
- *
- * 8192 kB
- *  User Space
- * 1024 kB
- *  Peripheral #8
- * 1024 kB
- *  Peripheral #7
- * ...
- * 1024 kB
- *  MMIO and Interrupt Vectors
- *  128 kB
- *   MMIO for Peri #8
- *  128 kB
- *   MMIO for Peri #7
- *  ...
- *  128 kB
- *   MMIO for the computer
- *   130816 bytes
- *    MMIO for Ports, etc.
- *   256 bytes
- *    Vectors for 64 interrupts
- *
- *
+ * A class representing an instance of a Virtual Machine
  */
 
 class VM(
     _memsize: Long,
-    val worldInterface: WorldInterface
+    val worldInterface: WorldInterface,
+    val roms: Array<VMProgramRom?> // first ROM must contain the BIOS
 ) {
 
     val id = java.util.Random().nextInt()
@@ -81,6 +44,9 @@ class VM(
 
     val startTime: Long
 
+    var romMapping = 255
+        internal set
+
     init {
         peripheralTable[0] = PeripheralEntry(
             "io",
@@ -217,9 +183,6 @@ class VM(
         mallocSizes.remove(index)
     }
 
-    //fun Byte.toLuaValue() = LuaValue.valueOf(this.toInt())
-
-
     internal data class VMNativePtr(val address: Int, val size: Int)
 }
 

src/net/torvald/tsvm/VMGUI.kt

@@ -7,14 +7,14 @@ import com.badlogic.gdx.graphics.OrthographicCamera
 import com.badlogic.gdx.graphics.g2d.SpriteBatch
 import kotlinx.coroutines.*
 import net.torvald.tsvm.CompressorDelegate.GZIP_HEADER
+import net.torvald.tsvm.peripheral.GenericBios
 import net.torvald.tsvm.peripheral.GraphicsAdapter
 import java.io.File
 
 fun ByteArray.startsWith(other: ByteArray) = this.sliceArray(other.indices).contentEquals(other)
 
-class VMGUI(val appConfig: LwjglApplicationConfiguration) : ApplicationAdapter() {
+class VMGUI(val vm: VM, val appConfig: LwjglApplicationConfiguration) : ApplicationAdapter() {
 
-    val vm = VM(64.kB(), TheRealWorld())
     lateinit var gpu: GraphicsAdapter
 
     lateinit var batch: SpriteBatch
@@ -54,19 +54,10 @@ class VMGUI(val appConfig: LwjglApplicationConfiguration) : ApplicationAdapter()
 
         memvwr = Memvwr(vm)
 
-        // load test bios
-
-        val bios = File("./assets/bios1.bin").readBytes()
-        // check if bios is compressed in gzip
-        val biosStr = if (bios.startsWith(GZIP_HEADER))
-            CompressorDelegate.decomp(bios).toString(VM.CHARSET)
-        else
-            bios.toString(VM.CHARSET)
 
         vmRunner = VMRunnerFactory(vm, "js")
         coroutineJob = GlobalScope.launch {
-            //vmRunner.executeCommand(File("./assets/zippytest.js").readText(VM.CHARSET))
-            vmRunner.executeCommand(biosStr)
+            vmRunner.executeCommand(vm.roms[0]!!.readAll())
         }
     }
 

src/net/torvald/tsvm/VMJSR223Delegate.kt

@@ -13,6 +13,13 @@ class VMJSR223Delegate(val vm: VM) {
     fun nanoTime() = System.nanoTime()
     fun malloc(size: Int) = vm.malloc(size)
     fun free(ptr: Int) = vm.free(ptr)
+    fun mapRom(slot: Int) {
+        vm.romMapping = slot.and(255)
+    }
+    fun romReadAll(): String {
+        if (vm.romMapping == 255) return ""
+        return vm.roms[vm.romMapping]!!.readAll()
+    }
 
     fun uptime(): Long {
         vm.poke(-69, -1)

src/net/torvald/tsvm/peripheral/IOSpace.kt

@@ -93,6 +93,8 @@ class IOSpace(val vm: VM) : PeriBase, InputProcessor {
             in 72..79 -> systemUptime.ushr((adi - 72) * 8).and(255).toByte()
             in 80..87 -> rtc.ushr((adi - 80) * 8).and(255).toByte()
 
+            88L -> vm.romMapping.toByte()
+
             4076L -> blockTransferPorts[0].statusCode.toByte()
             4077L -> blockTransferPorts[1].statusCode.toByte()
             4078L -> blockTransferPorts[2].statusCode.toByte()
@@ -119,6 +121,8 @@ class IOSpace(val vm: VM) : PeriBase, InputProcessor {
             in 12288..16383 -> blockTransferRx[2][addr - 12288]
             in 16384..20479 -> blockTransferRx[3][addr - 16384]
 
+            in 65536..131071 -> if (vm.romMapping == -1) 255.toByte() else vm.roms[vm.romMapping]?.get(adi - 65536)
+
             in 131072..262143 -> vm.peripheralTable[1].peripheral?.mmio_read(addr - 131072)
             in 262144..393215 -> vm.peripheralTable[2].peripheral?.mmio_read(addr - 262144)
             in 393216..524287 -> vm.peripheralTable[3].peripheral?.mmio_read(addr - 393216)
@@ -147,6 +151,8 @@ class IOSpace(val vm: VM) : PeriBase, InputProcessor {
                 RTClatched = byte.and(0b10).isNonZero()
             }
 
+            88L -> vm.romMapping = bi
+
             4076L -> blockTransferPorts[0].statusCode = bi
             4077L -> blockTransferPorts[1].statusCode = bi
             4078L -> blockTransferPorts[2].statusCode = bi

src/net/torvald/tsvm/peripheral/VMProgramRom.kt

@@ -0,0 +1,31 @@
+package net.torvald.tsvm.peripheral
+
+import net.torvald.tsvm.CompressorDelegate
+import net.torvald.tsvm.CompressorDelegate.GZIP_HEADER
+import net.torvald.tsvm.VM
+import net.torvald.tsvm.startsWith
+import java.io.File
+
+interface VMProgramRom {
+    fun readAll(): String
+    operator fun get(addr: Int): Byte
+}
+
+object GenericBios : VMProgramRom {
+    private val contents: ByteArray
+
+    init {
+        val bytes = File("./assets/bios/bios1.bin").readBytes()
+        contents = bytes.sliceArray(0 until minOf(65536, bytes.size))
+    }
+
+    override fun readAll(): String {
+        // check if bios is compressed in gzip
+        return if (contents.startsWith(GZIP_HEADER))
+            CompressorDelegate.decomp(contents).toString(VM.CHARSET)
+        else
+            contents.toString(VM.CHARSET)
+    }
+
+    override fun get(addr: Int): Byte = contents[addr]
+}

src/net/torvald/tsvm/vdc/V2kRunTest.kt

@@ -15,7 +15,7 @@ import net.torvald.tsvm.peripheral.GraphicsAdapter
 
 class V2kRunTest(val appConfig: LwjglApplicationConfiguration) : ApplicationAdapter() {
 
-    val vm = VM(64.kB(), TheRealWorld())
+    val vm = VM(64.kB(), TheRealWorld(), arrayOf())
     lateinit var gpu: GraphicsAdapter
 
     lateinit var batch: SpriteBatch

terranmon.txt

@@ -82,6 +82,8 @@ MMIO
 72..79 RO: System uptime in nanoseconds
 80..87 RO: RTC in microseconds
 
+88 RW: Rom mapping
+
 4076..4079 RW: 8-bit status code for the port
 4080..4083 RO: 8-bit status code for connected device
 
@@ -119,6 +121,8 @@ MMIO
 12288..16383 RW: Buffer for block transfer lane #3
 16384..20479 RW: Buffer for block transfer lane #4
 
+65536..131071 RO: Mapped to ROM
+
 --------------------------------------------------------------------------------
 
 VRAM Bank 0 (256 kB)