This is a BIOS emulator, porting from SciTech for u-boot, mainly for
ATI video card BIOS. and can be used for x86 code emulation by some
modifications.
Signed-off-by: Jason Jin <Jason.jin@freescale.com>
diff --git a/drivers/bios_emulator/x86emu/debug.c b/drivers/bios_emulator/x86emu/debug.c
new file mode 100644
index 0000000..0f58a69
--- /dev/null
+++ b/drivers/bios_emulator/x86emu/debug.c
@@ -0,0 +1,461 @@
+/****************************************************************************
+*
+* Realmode X86 Emulator Library
+*
+* Copyright (C) 1991-2004 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.
+*
+****************************************************************************/
+
+#include "x86emu/x86emui.h"
+#include <stdarg.h>
+
+/*----------------------------- 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("-");
+ 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++;
+
+ *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");
+}