diff options
Diffstat (limited to 'drivers/bios_emulator/x86emu/debug.c')
| -rw-r--r-- | drivers/bios_emulator/x86emu/debug.c | 465 |
1 files changed, 465 insertions, 0 deletions
diff --git a/drivers/bios_emulator/x86emu/debug.c b/drivers/bios_emulator/x86emu/debug.c new file mode 100644 index 0000000..915739c --- /dev/null +++ b/drivers/bios_emulator/x86emu/debug.c @@ -0,0 +1,465 @@ +/**************************************************************************** +* +* 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> + +#if defined(CONFIG_BIOSEMU) + +/*----------------------------- 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"); +} + +#endif |