lib/soft386/soft386.c

   1 /*
   2  * COPYRIGHT:       GPL - See COPYING in the top level directory
   3  * PROJECT:         386/486 CPU Emulation Library
   4  * FILE:            soft386.c
   5  * PURPOSE:         Functions meant for use by the host.
   6  * PROGRAMMERS:     Aleksandar Andrejevic <theflash AT sdf DOT lonestar DOT org>
   7  */
   8
   9 /* INCLUDES *******************************************************************/
  10
  11 // #define WIN32_NO_STATUS
  12 // #define _INC_WINDOWS
  13 #include <windef.h>
  14
  15 #include <soft386.h>
  16 #include "common.h"
  17 #include "opcodes.h"
  18
  19 // #define NDEBUG
  20 #include <debug.h>
  21
  22 /* DEFINES ********************************************************************/
  23
  24 typedef enum
  25 {
  26     SOFT386_STEP_INTO,
  27     SOFT386_STEP_OVER,
  28     SOFT386_STEP_OUT,
  29     SOFT386_CONTINUE
  30 } SOFT386_EXEC_CMD;
  31
  32 /* PRIVATE FUNCTIONS **********************************************************/
  33
  34 static
  35 inline
  36 VOID
  37 NTAPI
  38 Soft386ExecutionControl(PSOFT386_STATE State, INT Command)
  39 {
  40     UCHAR Opcode;
  41     INT ProcedureCallCount = 0;
  42
  43     /* Main execution loop */
  44     do
  45     {
  46         /* Perform an instruction fetch */
  47         if (!Soft386FetchByte(State, &Opcode)) continue;
  48
  49         // TODO: Check for CALL/RET to update ProcedureCallCount.
  50
  51         if (Soft386OpcodeHandlers[Opcode] != NULL)
  52         {
  53             /* Call the opcode handler */
  54             Soft386OpcodeHandlers[Opcode](State, Opcode);
  55         }
  56         else
  57         {
  58             /* This is not a valid opcode */
  59             Soft386Exception(State, SOFT386_EXCEPTION_UD);
  60         }
  61
  62         if (Soft386OpcodeHandlers[Opcode] != Soft386OpcodePrefix)
  63         {
  64             /* A non-prefix opcode has been executed, reset the prefix flags */
  65             State->PrefixFlags = 0;
  66         }
  67
  68         /* Increment the time stamp counter */
  69         State->TimeStampCounter++;
  70     }
  71     while ((Command == SOFT386_CONTINUE)
  72            || (Command == SOFT386_STEP_OVER && ProcedureCallCount > 0)
  73            || (Command == SOFT386_STEP_OUT && ProcedureCallCount >= 0));
  74 }
  75
  76 /* PUBLIC FUNCTIONS ***********************************************************/
  77
  78 VOID
  79 NTAPI
  80 Soft386Continue(PSOFT386_STATE State)
  81 {
  82     /* Call the internal function */
  83     Soft386ExecutionControl(State, SOFT386_CONTINUE);
  84 }
  85
  86 VOID
  87 NTAPI
  88 Soft386StepInto(PSOFT386_STATE State)
  89 {
  90     /* Call the internal function */
  91     Soft386ExecutionControl(State, SOFT386_STEP_INTO);
  92 }
  93
  94 VOID
  95 NTAPI
  96 Soft386StepOver(PSOFT386_STATE State)
  97 {
  98     /* Call the internal function */
  99     Soft386ExecutionControl(State, SOFT386_STEP_OVER);
 100 }
 101
 102 VOID
 103 NTAPI
 104 Soft386StepOut(PSOFT386_STATE State)
 105 {
 106     /* Call the internal function */
 107     Soft386ExecutionControl(State, SOFT386_STEP_OUT);
 108 }
 109
 110 VOID
 111 NTAPI
 112 Soft386DumpState(PSOFT386_STATE State)
 113 {
 114     DPRINT1("\nCPU currently executing in %s mode at %04X:%08X\n"
 115             "Time Stamp Counter = %016X\n",
 116             (State->ControlRegisters[0] & SOFT386_CR0_PE) ? "protected" : "real",
 117             State->SegmentRegs[SOFT386_REG_CS].Selector,
 118             State->InstPtr.Long,
 119             State->TimeStampCounter);
 120     DPRINT1("\nGeneral purpose registers:\n"
 121             "EAX = %08X\tECX = %08X\tEDX = %08X\tEBX = %08X\n"
 122             "ESP = %08X\tEBP = %08X\tESI = %08X\tEDI = %08X\n",
 123             State->GeneralRegs[SOFT386_REG_EAX].Long,
 124             State->GeneralRegs[SOFT386_REG_ECX].Long,
 125             State->GeneralRegs[SOFT386_REG_EDX].Long,
 126             State->GeneralRegs[SOFT386_REG_EBX].Long,
 127             State->GeneralRegs[SOFT386_REG_ESP].Long,
 128             State->GeneralRegs[SOFT386_REG_EBP].Long,
 129             State->GeneralRegs[SOFT386_REG_ESI].Long,
 130             State->GeneralRegs[SOFT386_REG_EDI].Long);
 131     DPRINT1("\nSegment registers:\n"
 132             "ES = %04X (Base: %08X, Limit: %08X, Dpl: %u)\n"
 133             "CS = %04X (Base: %08X, Limit: %08X, Dpl: %u)\n"
 134             "SS = %04X (Base: %08X, Limit: %08X, Dpl: %u)\n"
 135             "DS = %04X (Base: %08X, Limit: %08X, Dpl: %u)\n"
 136             "FS = %04X (Base: %08X, Limit: %08X, Dpl: %u)\n"
 137             "GS = %04X (Base: %08X, Limit: %08X, Dpl: %u)\n",
 138             State->SegmentRegs[SOFT386_REG_ES].Selector,
 139             State->SegmentRegs[SOFT386_REG_ES].Base,
 140             State->SegmentRegs[SOFT386_REG_ES].Limit,
 141             State->SegmentRegs[SOFT386_REG_ES].Dpl,
 142             State->SegmentRegs[SOFT386_REG_CS].Selector,
 143             State->SegmentRegs[SOFT386_REG_CS].Base,
 144             State->SegmentRegs[SOFT386_REG_CS].Limit,
 145             State->SegmentRegs[SOFT386_REG_CS].Dpl,
 146             State->SegmentRegs[SOFT386_REG_SS].Selector,
 147             State->SegmentRegs[SOFT386_REG_SS].Base,
 148             State->SegmentRegs[SOFT386_REG_SS].Limit,
 149             State->SegmentRegs[SOFT386_REG_SS].Dpl,
 150             State->SegmentRegs[SOFT386_REG_DS].Selector,
 151             State->SegmentRegs[SOFT386_REG_DS].Base,
 152             State->SegmentRegs[SOFT386_REG_DS].Limit,
 153             State->SegmentRegs[SOFT386_REG_DS].Dpl,
 154             State->SegmentRegs[SOFT386_REG_FS].Selector,
 155             State->SegmentRegs[SOFT386_REG_FS].Base,
 156             State->SegmentRegs[SOFT386_REG_FS].Limit,
 157             State->SegmentRegs[SOFT386_REG_FS].Dpl,
 158             State->SegmentRegs[SOFT386_REG_GS].Selector,
 159             State->SegmentRegs[SOFT386_REG_GS].Base,
 160             State->SegmentRegs[SOFT386_REG_GS].Limit,
 161             State->SegmentRegs[SOFT386_REG_GS].Dpl);
 162     DPRINT1("\nFlags: %08X (%s %s %s %s %s %s %s %s %s %s %s %s %s %s %s) Iopl: %u\n",
 163             State->Flags.Long,
 164             State->Flags.Cf ? "CF" : "cf",
 165             State->Flags.Pf ? "PF" : "pf",
 166             State->Flags.Af ? "AF" : "af",
 167             State->Flags.Zf ? "ZF" : "zf",
 168             State->Flags.Sf ? "SF" : "sf",
 169             State->Flags.Tf ? "TF" : "tf",
 170             State->Flags.If ? "IF" : "if",
 171             State->Flags.Df ? "DF" : "df",
 172             State->Flags.Of ? "OF" : "of",
 173             State->Flags.Nt ? "NT" : "nt",
 174             State->Flags.Rf ? "RF" : "rf",
 175             State->Flags.Vm ? "VM" : "vm",
 176             State->Flags.Ac ? "AC" : "ac",
 177             State->Flags.Vif ? "VIF" : "vif",
 178             State->Flags.Vip ? "VIP" : "vip",
 179             State->Flags.Iopl);
 180     DPRINT1("\nControl Registers:\n"
 181             "CR0 = %08X\tCR1 = %08X\tCR2 = %08X\tCR3 = %08X\n"
 182             "CR4 = %08X\tCR5 = %08X\tCR6 = %08X\tCR7 = %08X\n",
 183             State->ControlRegisters[SOFT386_REG_CR0],
 184             State->ControlRegisters[SOFT386_REG_CR1],
 185             State->ControlRegisters[SOFT386_REG_CR2],
 186             State->ControlRegisters[SOFT386_REG_CR3],
 187             State->ControlRegisters[SOFT386_REG_CR4],
 188             State->ControlRegisters[SOFT386_REG_CR5],
 189             State->ControlRegisters[SOFT386_REG_CR6],
 190             State->ControlRegisters[SOFT386_REG_CR7]);
 191     DPRINT1("\nDebug Registers:\n"
 192             "DR0 = %08X\tDR1 = %08X\tDR2 = %08X\tDR3 = %08X\n"
 193             "DR4 = %08X\tDR5 = %08X\tDR6 = %08X\tDR7 = %08X\n",
 194             State->DebugRegisters[SOFT386_REG_DR0],
 195             State->DebugRegisters[SOFT386_REG_DR1],
 196             State->DebugRegisters[SOFT386_REG_DR2],
 197             State->DebugRegisters[SOFT386_REG_DR3],
 198             State->DebugRegisters[SOFT386_REG_DR4],
 199             State->DebugRegisters[SOFT386_REG_DR5],
 200             State->DebugRegisters[SOFT386_REG_DR6],
 201             State->DebugRegisters[SOFT386_REG_DR7]);
 202 }
 203
 204 VOID
 205 NTAPI
 206 Soft386Reset(PSOFT386_STATE State)
 207 {
 208     INT i;
 209     SOFT386_MEM_READ_PROC MemReadCallback = State->MemReadCallback;
 210     SOFT386_MEM_WRITE_PROC MemWriteCallback = State->MemWriteCallback;
 211     SOFT386_IO_READ_PROC IoReadCallback = State->IoReadCallback;
 212     SOFT386_IO_WRITE_PROC IoWriteCallback = State->IoWriteCallback;
 213     SOFT386_IDLE_PROC IdleCallback = State->IdleCallback;
 214
 215     /* Clear the entire structure */
 216     RtlZeroMemory(State, sizeof(*State));
 217
 218     /* Initialize the registers */
 219     State->Flags.AlwaysSet = 1;
 220     State->InstPtr.LowWord = 0xFFF0;
 221
 222     /* Initialize segments */
 223     for (i = 0; i < SOFT386_NUM_SEG_REGS; i++)
 224     {
 225         /* Set the selector, base and limit, other values don't apply in real mode */
 226         State->SegmentRegs[i].Selector = 0;
 227         State->SegmentRegs[i].Base = 0;
 228         State->SegmentRegs[i].Limit = 0xFFFF;
 229     }
 230
 231     /* Initialize the code segment */
 232     State->SegmentRegs[SOFT386_REG_CS].Selector = 0xF000;
 233     State->SegmentRegs[SOFT386_REG_CS].Base = 0xFFFF0000;
 234
 235     /* Initialize the IDT */
 236     State->Idtr.Size = 0x3FF;
 237     State->Idtr.Address = 0;
 238
 239     /* Initialize CR0 */
 240     State->ControlRegisters[SOFT386_REG_CR0] |= SOFT386_CR0_ET;
 241
 242     /* Restore the callbacks */
 243     State->MemReadCallback = MemReadCallback;
 244     State->MemWriteCallback = MemWriteCallback;
 245     State->IoReadCallback = IoReadCallback;
 246     State->IoWriteCallback = IoWriteCallback;
 247     State->IdleCallback = IdleCallback;
 248 }
 249
 250 VOID
 251 NTAPI
 252 Soft386Interrupt(PSOFT386_STATE State, UCHAR Number)
 253 {
 254     // TODO: NOT IMPLEMENTED!!!
 255     UNIMPLEMENTED;
 256 }
 257
 258 VOID
 259 NTAPI
 260 Soft386ExecuteAt(PSOFT386_STATE State, USHORT Segment, ULONG Offset)
 261 {
 262     /* Load the new CS */
 263     if (!Soft386LoadSegment(State, SOFT386_REG_CS, Segment))
 264     {
 265         /* An exception occurred, let the handler execute instead */
 266         return;
 267     }
 268
 269     /* Set the new IP */
 270     State->InstPtr.Long = Offset;
 271 }
 272
 273 /* EOF */