Add x86 CPU emulator for BIOS int10 emulation on non x86 arches.

1 files changed, 431 insertions, 0 deletions

diff --git a/tools/ddcprobe/x86emu/debug.c b/tools/ddcprobe/x86emu/debug.c
new file mode 100644
index 000000000..ed8f2f0e0
--- /dev/null
+++ b/tools/ddcprobe/x86emu/debug.c
@@ -0,0 +1,431 @@
+/****************************************************************************
+*
+*						Realmode X86 Emulator Library
+*
+*            	Copyright (C) 1996-1999 SciTech Software, Inc.
+* 				     Copyright (C) David Mosberger-Tang
+* 					   Copyright (C) 1999 Egbert Eich
+*
+*  ========================================================================
+*
+*  Permission to use, copy, modify, distribute, and sell this software and
+*  its documentation for any purpose is hereby granted without fee,
+*  provided that the above copyright notice appear in all copies and that
+*  both that copyright notice and this permission notice appear in
+*  supporting documentation, and that the name of the authors not be used
+*  in advertising or publicity pertaining to distribution of the software
+*  without specific, written prior permission.  The authors makes no
+*  representations about the suitability of this software for any purpose.
+*  It is provided "as is" without express or implied warranty.
+*
+*  THE AUTHORS DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
+*  INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
+*  EVENT SHALL THE AUTHORS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
+*  CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF
+*  USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
+*  OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+*  PERFORMANCE OF THIS SOFTWARE.
+*
+*  ========================================================================
+*
+* Language:		ANSI C
+* Environment:	Any
+* Developer:    Kendall Bennett
+*
+* Description:  This file contains the code to handle debugging of the
+*				emulator.
+*
+****************************************************************************/
+/* $XFree86: xc/extras/x86emu/src/x86emu/debug.c,v 1.2 2000/04/05 18:13:14 dawes Exp $ */
+
+#include "x86emu/x86emui.h"
+#ifdef IN_MODULE
+#include "xf86_ansic.h"
+#else
+#include <stdarg.h>
+#include <stdlib.h>
+#endif
+
+/*----------------------------- Implementation ----------------------------*/
+
+#ifdef DEBUG
+
+static void     print_encoded_bytes (u16 s, u16 o);
+static void     print_decoded_instruction (void);
+static int      parse_line (char *s, int *ps, int *n);
+  
+/* should look something like debug's output. */
+void X86EMU_trace_regs (void)
+{
+	if (DEBUG_TRACE()) {
+		x86emu_dump_regs();
+    }
+	if (DEBUG_DECODE() && ! DEBUG_DECODE_NOPRINT()) {
+		printk("%04x:%04x ",M.x86.saved_cs, M.x86.saved_ip);
+		print_encoded_bytes( M.x86.saved_cs, M.x86.saved_ip);
+		print_decoded_instruction();
+    }
+}
+
+void X86EMU_trace_xregs (void)
+{
+	if (DEBUG_TRACE()) {
+		x86emu_dump_xregs();
+    }
+}
+
+void x86emu_just_disassemble (void)
+{
+    /*
+     * This routine called if the flag DEBUG_DISASSEMBLE is set kind
+     * of a hack!
+     */
+	printk("%04x:%04x ",M.x86.saved_cs, M.x86.saved_ip);
+	print_encoded_bytes( M.x86.saved_cs, M.x86.saved_ip);
+	print_decoded_instruction();
+}
+
+static void disassemble_forward (u16 seg, u16 off, int n)
+{
+	X86EMU_sysEnv tregs;
+	int i;
+	u8 op1;
+    /*
+     * hack, hack, hack.  What we do is use the exact machinery set up
+     * for execution, except that now there is an additional state
+     * flag associated with the "execution", and we are using a copy
+     * of the register struct.  All the major opcodes, once fully
+     * decoded, have the following two steps: TRACE_REGS(r,m);
+     * SINGLE_STEP(r,m); which disappear if DEBUG is not defined to
+     * the preprocessor.  The TRACE_REGS macro expands to:
+     *
+     * if (debug&DEBUG_DISASSEMBLE) 
+     *     {just_disassemble(); goto EndOfInstruction;}
+     *     if (debug&DEBUG_TRACE) trace_regs(r,m);
+     *
+     * ......  and at the last line of the routine. 
+     *
+     * EndOfInstruction: end_instr();
+     *
+     * Up to the point where TRACE_REG is expanded, NO modifications
+     * are done to any register EXCEPT the IP register, for fetch and
+     * decoding purposes.
+     *
+     * This was done for an entirely different reason, but makes a
+     * nice way to get the system to help debug codes.
+     */
+	tregs = M;
+    tregs.x86.R_IP = off;
+    tregs.x86.R_CS = seg;
+    
+    /* reset the decoding buffers */
+    tregs.x86.enc_str_pos = 0;
+    tregs.x86.enc_pos = 0;
+    
+    /* turn on the "disassemble only, no execute" flag */
+    tregs.x86.debug |= DEBUG_DISASSEMBLE_F;
+ 
+    /* DUMP NEXT n instructions to screen in straight_line fashion */
+    /*
+     * This looks like the regular instruction fetch stream, except
+     * that when this occurs, each fetched opcode, upon seeing the
+     * DEBUG_DISASSEMBLE flag set, exits immediately after decoding
+     * the instruction.  XXX --- CHECK THAT MEM IS NOT AFFECTED!!!
+     * Note the use of a copy of the register structure...
+     */
+    for (i=0; i<n; i++) {
+		op1 = (*sys_rdb)(((u32)M.x86.R_CS<<4) + (M.x86.R_IP++));
+		(x86emu_optab[op1])(op1);
+    }
+    /* end major hack mode. */
+}
+
+void x86emu_check_ip_access (void)
+{
+    /* NULL as of now */
+}
+
+void x86emu_check_sp_access (void)
+{
+}
+
+void x86emu_check_mem_access (u32 dummy)
+{
+	/*  check bounds, etc */
+}
+
+void x86emu_check_data_access (uint dummy1, uint dummy2)
+{
+	/*  check bounds, etc */
+}
+
+void x86emu_inc_decoded_inst_len (int x)
+{
+	M.x86.enc_pos += x;
+}
+
+void x86emu_decode_printf (char *x)
+{
+	sprintf(M.x86.decoded_buf+M.x86.enc_str_pos,"%s",x);
+	M.x86.enc_str_pos += strlen(x);
+}
+
+void x86emu_decode_printf2 (char *x, int y)
+{
+	char temp[100];
+	sprintf(temp,x,y);
+	sprintf(M.x86.decoded_buf+M.x86.enc_str_pos,"%s",temp);
+	M.x86.enc_str_pos += strlen(temp);
+}
+
+void x86emu_end_instr (void)
+{
+	M.x86.enc_str_pos = 0;
+	M.x86.enc_pos = 0;
+}
+
+static void print_encoded_bytes (u16 s, u16 o)
+{
+    int i;
+    char buf1[64];
+	for (i=0; i< M.x86.enc_pos; i++) {
+		sprintf(buf1+2*i,"%02x", fetch_data_byte_abs(s,o+i));
+    }
+	printk("%-20s",buf1);
+}
+
+static void print_decoded_instruction (void)
+{
+	printk("%s", M.x86.decoded_buf);
+}
+
+void x86emu_print_int_vect (u16 iv)
+{
+	u16 seg,off;
+
+	if (iv > 256) return;
+	seg   = fetch_data_word_abs(0,iv*4);
+	off   = fetch_data_word_abs(0,iv*4+2);
+	printk("%04x:%04x ", seg, off);
+}
+
+void X86EMU_dump_memory (u16 seg, u16 off, u32 amt)
+{
+	u32 start = off & 0xfffffff0;
+	u32 end  = (off+16) & 0xfffffff0;
+	u32 i;
+	u32 current;
+
+	current = start;
+	while (end <= off + amt) {
+		printk("%04x:%04x ", seg, start);
+		for (i=start; i< off; i++)
+		  printk("   ");
+		for (       ; i< end; i++)
+		  printk("%02x ", fetch_data_byte_abs(seg,i));
+		printk("\n");
+		start = end;
+		end = start + 16;
+	}
+}
+
+void x86emu_single_step (void)
+{
+    char s[1024];
+    int ps[10];
+    int ntok;
+    int cmd;
+    int done;
+		int segment;
+    int offset;
+    static int breakpoint;
+    static int noDecode = 1;
+    
+    char *p;
+
+		if (DEBUG_BREAK()) {
+				if (M.x86.saved_ip != breakpoint) {
+						return;
+				} else {
+ 	          M.x86.debug &= ~DEBUG_DECODE_NOPRINT_F;
+						M.x86.debug |= DEBUG_TRACE_F;
+						M.x86.debug &= ~DEBUG_BREAK_F;
+						print_decoded_instruction ();
+						X86EMU_trace_regs();
+				}
+		}
+    done=0;
+	offset = M.x86.saved_ip;
+    while (!done) {
+        printk("-");
+        p = fgets(s, 1023, stdin);
+        cmd = parse_line(s, ps, &ntok);
+        switch(cmd) {
+          case 'u':
+			disassemble_forward(M.x86.saved_cs,(u16)offset,10);
+            break;
+          case 'd':  
+							if (ntok == 2) {
+									segment = M.x86.saved_cs;
+									offset = ps[1];
+									X86EMU_dump_memory(segment,(u16)offset,16);
+									offset += 16;
+							} else if (ntok == 3) {
+									segment = ps[1];
+									offset = ps[2];
+									X86EMU_dump_memory(segment,(u16)offset,16);
+									offset += 16;
+							} else {
+									segment = M.x86.saved_cs;
+									X86EMU_dump_memory(segment,(u16)offset,16);
+									offset += 16;
+							}
+            break;
+          case 'c':
+			M.x86.debug ^= DEBUG_TRACECALL_F;
+            break;
+          case 's':
+			M.x86.debug ^= DEBUG_SVC_F | DEBUG_SYS_F | DEBUG_SYSINT_F;
+            break;
+          case 'r':
+			X86EMU_trace_regs();
+            break;
+          case 'x':
+			X86EMU_trace_xregs();
+            break;
+          case 'g':
+            if (ntok == 2) {
+                breakpoint = ps[1];
+		if (noDecode) {
+		                M.x86.debug |= DEBUG_DECODE_NOPRINT_F;
+		} else {
+		                M.x86.debug &= ~DEBUG_DECODE_NOPRINT_F;
+		}
+		M.x86.debug &= ~DEBUG_TRACE_F;
+		M.x86.debug |= DEBUG_BREAK_F;
+		done = 1;
+            }
+            break;
+          case 'q':
+          M.x86.debug |= DEBUG_EXIT;
+          return;
+	  case 'P':
+	      noDecode = (noDecode)?0:1;
+	      printk("Toggled decoding to %s\n",(noDecode)?"FALSE":"TRUE");
+	      break;
+          case 't':
+	  case 0:
+            done = 1;
+            break;
+        }   
+    }
+}
+
+int X86EMU_trace_on(void)
+{
+	return M.x86.debug |= DEBUG_STEP_F | DEBUG_DECODE_F | DEBUG_TRACE_F;
+}
+
+int X86EMU_trace_off(void)
+{
+	return M.x86.debug &= ~(DEBUG_STEP_F | DEBUG_DECODE_F | DEBUG_TRACE_F);
+}
+
+static int parse_line (char *s, int *ps, int *n)
+{
+    int cmd;
+
+    *n = 0;
+    while(*s == ' ' || *s == '\t') s++;
+    ps[*n] = *s;
+    switch (*s) {
+      case '\n':
+        *n += 1;
+        return 0;
+      default:
+        cmd = *s;
+        *n += 1;
+    }
+
+	while (1) {
+		while (*s != ' ' && *s != '\t' && *s != '\n')  s++;
+		
+		if (*s == '\n')
+			return cmd;
+		
+		while(*s == ' ' || *s == '\t') s++;
+		
+		sscanf(s,"%x",&ps[*n]);
+		*n += 1;
+	}
+}
+
+#endif /* DEBUG */
+
+void x86emu_dump_regs (void)
+{
+	printk("\tAX=%04x  ", M.x86.R_AX );
+	printk("BX=%04x  ", M.x86.R_BX );
+	printk("CX=%04x  ", M.x86.R_CX );
+	printk("DX=%04x  ", M.x86.R_DX );
+	printk("SP=%04x  ", M.x86.R_SP );
+	printk("BP=%04x  ", M.x86.R_BP );
+	printk("SI=%04x  ", M.x86.R_SI );
+	printk("DI=%04x\n", M.x86.R_DI );
+	printk("\tDS=%04x  ", M.x86.R_DS );
+	printk("ES=%04x  ", M.x86.R_ES );
+	printk("SS=%04x  ", M.x86.R_SS );
+	printk("CS=%04x  ", M.x86.R_CS );
+	printk("IP=%04x   ", M.x86.R_IP );
+	if (ACCESS_FLAG(F_OF))    printk("OV ");     /* CHECKED... */
+	else                        printk("NV ");
+	if (ACCESS_FLAG(F_DF))    printk("DN ");
+	else                        printk("UP ");
+	if (ACCESS_FLAG(F_IF))    printk("EI ");
+	else                        printk("DI ");
+	if (ACCESS_FLAG(F_SF))    printk("NG ");
+	else                        printk("PL ");
+	if (ACCESS_FLAG(F_ZF))    printk("ZR ");
+	else                        printk("NZ ");
+	if (ACCESS_FLAG(F_AF))    printk("AC ");
+	else                        printk("NA ");
+	if (ACCESS_FLAG(F_PF))    printk("PE ");
+	else                        printk("PO ");
+	if (ACCESS_FLAG(F_CF))    printk("CY ");
+	else                        printk("NC ");
+	printk("\n");
+}
+
+void x86emu_dump_xregs (void)
+{
+	printk("\tEAX=%08x  ", M.x86.R_EAX );
+	printk("EBX=%08x  ", M.x86.R_EBX );
+	printk("ECX=%08x  ", M.x86.R_ECX );
+	printk("EDX=%08x  \n", M.x86.R_EDX );
+	printk("\tESP=%08x  ", M.x86.R_ESP );
+	printk("EBP=%08x  ", M.x86.R_EBP );
+	printk("ESI=%08x  ", M.x86.R_ESI );
+	printk("EDI=%08x\n", M.x86.R_EDI );
+	printk("\tDS=%04x  ", M.x86.R_DS );
+	printk("ES=%04x  ", M.x86.R_ES );
+	printk("SS=%04x  ", M.x86.R_SS );
+	printk("CS=%04x  ", M.x86.R_CS );
+	printk("EIP=%08x\n\t", M.x86.R_EIP );
+	if (ACCESS_FLAG(F_OF))    printk("OV ");     /* CHECKED... */
+	else                        printk("NV ");
+	if (ACCESS_FLAG(F_DF))    printk("DN ");
+	else                        printk("UP ");
+	if (ACCESS_FLAG(F_IF))    printk("EI ");
+	else                        printk("DI ");
+	if (ACCESS_FLAG(F_SF))    printk("NG ");
+	else                        printk("PL ");
+	if (ACCESS_FLAG(F_ZF))    printk("ZR ");
+	else                        printk("NZ ");
+	if (ACCESS_FLAG(F_AF))    printk("AC ");
+	else                        printk("NA ");
+	if (ACCESS_FLAG(F_PF))    printk("PE ");
+	else                        printk("PO ");
+	if (ACCESS_FLAG(F_CF))    printk("CY ");
+	else                        printk("NC ");
+	printk("\n");
+}