Getting Started¶

• Table of contents
• Getting Started
  • General notes
  • Aarch64
  • MIPS32
  • PowerPC32
  • RISC-V
  • X86 (8086 case)

General notes¶

First of all, install the QEMU4V.

It is possible to terminate QEMU by hands only. Neither Ctrl-C nor Ctrl-Z works, use kill <process-id> or killall qemu-system*.

Aarch64¶

It is supposed that Aarch64 toolchain is already installed in your system.

1. Write a simple Aarch64 program (it is called sample.s) that does nothing but puts 0x10 value to X0 register and then halts. Here it is:
   

   .text
       .globl _start
       bl _start
   _start:
       movz x1, #0x10, LSL #0
       hlt #57005
   

2. To compile the Aarch64 assembler program, do the following:
   

   aarch64-linux-gnu-as sample.s -o sample.o
   aarch64-linux-gnu-ld sample.o -o sample.elf
   aarch64-linux-gnu-objcopy -O binary sample.elf sample.bin
   

3. Finally, run QEMU4V emulator with enabled option of microprocessor execution trace logging:
   

   qemu-system-aarch64 -M virt -cpu cortex-a57 -bios sample.bin -d nochain,in_asm -singlestep -nographic -trace-log -D log-file.txt
   

4. Wait for a while, then stop QEMU4V. The following log-file.txt trace file should be generated:
   

   0 clk IT (0) 0000000000000000 94000001 A svc_ns : bl #+0x4 (addr 0x4)
   1 clk IT (1) 0000000000000004 d2800201 A svc_ns : movz x1, #0x10, LSL #0
   2 clk IT (2) 0000000000000008 d45bd5a0 A svc_ns : hlt #57005
   

MIPS32¶

It is supposed that MIPS toolchain is already installed in your system.

1. First of all, let's write a simple MIPS program (it is called sample.s) that stores 0x10 value at x12345678 address. Here it is:
   

   .text
       .globl _start
   _start:
   lui $1, 0x1234
   ori $1, $1, 0x5678
   addi $8, $0, 10
   sw $8, 0($1)
   

2. To compile the MIPS32 assembler program, do the following:
   

   mips-linux-gnu-as sample.s -o sample.o
   mips-linux-gnu-ld sample.o -Ttext 0xbfc00000 -o sample.elf
   

3. Finally, run QEMU4V emulator:
   

   qemu-system-mips -M mips -cpu mips32r6-generic -d unimp,nochain,in_asm -nographic -singlestep -D log.txt -bios sample.elf
   

4. Wait for a while, then stop QEMU4V. The following log-file.txt trace file should be generated:
   

   ...
   ----------------
   IN: 
   0xbfc0fffc:  nop
   
   ----------------
   IN: 
   0xbfc10000:  lui    at,0x1234
   
   ----------------
   IN: 
   0xbfc10004:  ori    at,at,0x5678
   
   ----------------
   IN: 
   0xbfc10008:  beqzalc    zero,t0,0xbfc10034
   
   ----------------
   IN: 
   0xbfc10034:  cache    0x0,0(s8)
   

PowerPC32¶

It is supposed that PowerPC toolchain is already installed in your system.

1. Write a simple PowerPC program (it is called p1.s). Here it is:
   

   .section    .text
       addi    4,0,5       # bad
       la  3,3(0)      # very bad
       la  3,0(3)
       la  5,2500(3)
   

2. To compile the PowerPC assembler program, do the following:
   

   powerpc-linux-gnu-as p1.s -me500mc -o p1.o
   powerpc-linux-gnu-ld p1.o -Ttext 0x0 -o p1.elf
   

3. Finally, run QEMU4V emulator:
   

   qemu-system-ppc -M ppce500 -cpu e500 -d unimp,nochain,in_asm -nographic -singlestep -bios p1.elf
   

4. Wait for a while, then stop QEMU4V. The following trace should be generated:
   

   IN: 
   0x00000000:  li      r4,5
   
   IN: 
   0x00000004:  li      r3,3
   
   IN: 
   0x00000008:  addi    r3,r3,0
   
   IN: 
   0x0000000c:  addi    r5,r3,2500
   
   

RISC-V¶

It is supposed that RISC-V toolchain is already installed in your system.

1. Write a simple RISC-V program (it is called sample.s) that does nothing but puts 0x18 value to t1 register and puts 0x21 value to t2 register. Here it is:
   

   .text
   .globl _start
   _start:
    addi t1, zero, 0x18
    addi t2, zero, 0x21
   

2. To compile the RISC-V assembler program, do the following:
   

   aarch64-linux-gnu-as sample.s -o sample.o
   aarch64-linux-gnu-ld sample.o -Ttext 0x1000 -o sample.elf
   

3. Finally, run QEMU4V emulator with enabled option of microprocessor execution trace logging (0x1000 value was used by linker because of QEMU-related features):
   

   qemu-system-riscv64 -M spike_v1.10 -cpu any -d unimp,nochain,in_asm -nographic -singlestep -trace-log -kernel sample.elf
   

4. Wait for a while, then stop QEMU4V. The following trace should be generated:
   

   0 clk 0 IT (0) 0000000000001000 01800313 A svc_ns : li t1,24
   1 clk R t1 0000000000000018
   1 clk 0 IT (1) 0000000000001004 02100393 A svc_ns : li t2,33
   2 clk R t2 0000000000000021
   2 clk 0 IT (2) 0000000000001008 00000000 A svc_ns : unimp
   3 clk 0 IT (3) 0000000000001010 00000000 A svc_ns : unimp
   

X86 (8086 case)¶

It is supposed that GCC is already installed in your system.

1. Write a simple X86 program (it is called sample.s) that performs some calculations:
   

   .code16 # tell the assembler that we're using 16 bit mode
       .text
       .global _start
   _start:
       mov $11, %AX
       and $204, %BX
       mov %AX, %CX
       add %CX, %BX
       sub %CX, %AX
   .org 510 # magic bytes that tell BIOS that this is bootable
   .word 0xaa55 # magic bytes that tell BIOS that this is bootable
   

2. To compile the X86 GNU assembler program, do the following:
   

   x86_64-linux-gnu-as sample.s -o sample.o
   x86_64-linux-gnu-ld sample.o -T 0x7c00 --oformat binary -o sample.elf
   

3. Finally, run QEMU4V emulator:
   

   qemu-system-i386 -d unimp,nochain,in_asm -nographic -singlestep -D log.txt -hda sample.elf
   

4. Wait for a while, then stop QEMU4V. The following log-file.txt trace file should be generated (go to the 0x7c00 address and see the program execution fragment):
   

   ----------------
   IN: 
   0x00007c00:  mov    $0xb,%ax
   
   ----------------
   IN: 
   0x00007c03:  and    $0xcc,%bx
   
   ----------------
   IN: 
   0x00007c07:  mov    %ax,%cx
   
   ----------------
   IN: 
   0x00007c09:  add    %cx,%bx
   
   ----------------
   IN: 
   0x00007c0b:  sub    %cx,%ax
   
   ----------------