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QbasicJacky

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注册时间： 2020-01-07

已发帖子： 14

积分： 14

反汇编 u-boot 的elf 文件 ,怎么才能 跟源码对应上,没有混排方式 @晕哥 大大

通过 arm-linux-gnueabihf-objdump -D u-boot > u-boot.dis
但是 生成的 代码 是纯汇编,两者没有混排起来,不知道 那些虹 被执行了
有没有 生成 混排起来的 反汇编, 应该是 gcc 优化掉了 它对应的调试消息 怎么改
例如:函数 s_init对应的 C 代码是

void s_init(void)
{
    /*
     * Undocumented magic taken from boot0, without this DRAM
     * access gets messed up (seems cache related).
     * The boot0 sources describe this as: "config ema for cache sram"
     */
#if defined CONFIG_MACH_SUN6I
    setbits_le32(SUNXI_SRAMC_BASE + 0x44, 0x1800);
#elif defined CONFIG_MACH_SUN8I
    __maybe_unused uint version;

    /* Unlock sram version info reg, read it, relock */
    setbits_le32(SUNXI_SRAMC_BASE + 0x24, (1 << 15));
    version = readl(SUNXI_SRAMC_BASE + 0x24) >> 16;
    clrbits_le32(SUNXI_SRAMC_BASE + 0x24, (1 << 15));

    /*
     * Ideally this would be a switch case, but we do not know exactly
     * which versions there are and which version needs which settings,
     * so reproduce the per SoC code from the BSP.
     */
#if defined CONFIG_MACH_SUN8I_A23
    if (version == 0x1650)
        setbits_le32(SUNXI_SRAMC_BASE + 0x44, 0x1800);
    else /* 0x1661 ? */
        setbits_le32(SUNXI_SRAMC_BASE + 0x44, 0xc0);
#elif defined CONFIG_MACH_SUN8I_A33
    if (version != 0x1667)
        setbits_le32(SUNXI_SRAMC_BASE + 0x44, 0xc0);
#endif
    /* A83T BSP never modifies SUNXI_SRAMC_BASE + 0x44 */
    /* No H3 BSP, boot0 seems to not modify SUNXI_SRAMC_BASE + 0x44 */
#endif

#if defined CONFIG_MACH_SUN6I || \
    defined CONFIG_MACH_SUN7I || \
    defined CONFIG_MACH_SUN8I || \
    defined CONFIG_MACH_SUN9I
    /* Enable SMP mode for CPU0, by setting bit 6 of Auxiliary Ctl reg */
    asm volatile(
        "mrc p15, 0, r0, c1, c0, 1\n"
        "orr r0, r0, #1 << 6\n"
        "mcr p15, 0, r0, c1, c0, 1\n");
#endif
#if defined CONFIG_MACH_SUN6I || defined CONFIG_MACH_SUN8I_H3
    /* Enable non-secure access to some peripherals */
    tzpc_init();
#endif

    clock_init();
    timer_init();
    gpio_init();
    i2c_init_board();
    eth_init_board();
}

对应的 汇编是:

42e01140 <s_init>:
42e01140:    e3a03507     mov    r3, #29360128    ; 0x1c00000
42e01144:    e92d4010     push    {r4, lr}
42e01148:    e5932024     ldr    r2, [r3, #36]    ; 0x24
42e0114c:    e3822902     orr    r2, r2, #32768    ; 0x8000
42e01150:    e5832024     str    r2, [r3, #36]    ; 0x24
42e01154:    e5932024     ldr    r2, [r3, #36]    ; 0x24
42e01158:    f57ff05f     dmb    sy
42e0115c:    e5932024     ldr    r2, [r3, #36]    ; 0x24
42e01160:    e3c22902     bic    r2, r2, #32768    ; 0x8000
42e01164:    e5832024     str    r2, [r3, #36]    ; 0x24
42e01168:    ee110f30     mrc    15, 0, r0, cr1, cr0, {1}
42e0116c:    e3800040     orr    r0, r0, #64    ; 0x40
42e01170:    ee010f30     mcr    15, 0, r0, cr1, cr0, {1}
42e01174:    eb000023     bl    42e01208 <clock_init>
42e01178:    ebfffd29     bl    42e00624 <timer_init>
42e0117c:    e3a01003     mov    r1, #3
42e01180:    e3a00028     mov    r0, #40    ; 0x28
42e01184:    eb00004e     bl    42e012c4 <sunxi_gpio_set_cfgpin>
42e01188:    e3a01003     mov    r1, #3
42e0118c:    e3a00029     mov    r0, #41    ; 0x29
42e01190:    eb00004b     bl    42e012c4 <sunxi_gpio_set_cfgpin>
42e01194:    e3a01001     mov    r1, #1
42e01198:    e3a00029     mov    r0, #41    ; 0x29
42e0119c:    eb000074     bl    42e01374 <sunxi_gpio_set_pull>
42e011a0:    e8bd4010     pop    {r4, lr}
42e011a4:    ea000190     b    42e017ec <i2c_init_board>

QbasicJacky

会员

注册时间： 2020-01-07

已发帖子： 14

积分： 14

Re: 反汇编 u-boot 的elf 文件 ,怎么才能 跟源码对应上,没有混排方式 @晕哥 大大

输入 命令
arm-linux-gnueabihf-objdump -S  u-boot>u-boot.dis
就能得到 混编 的 uboot 反汇编文件

42e01140 <s_init>:
    setbits_le32(SUNXI_SRAMC_BASE + 0x44, 0x1800);
#elif defined CONFIG_MACH_SUN8I
    __maybe_unused uint version;

    /* Unlock sram version info reg, read it, relock */
    setbits_le32(SUNXI_SRAMC_BASE + 0x24, (1 << 15));
42e01140:    e3a03507     mov    r3, #29360128    ; 0x1c00000
{
42e01144:    e92d4010     push    {r4, lr}
    setbits_le32(SUNXI_SRAMC_BASE + 0x24, (1 << 15));
42e01148:    e5932024     ldr    r2, [r3, #36]    ; 0x24
42e0114c:    e3822902     orr    r2, r2, #32768    ; 0x8000
42e01150:    e5832024     str    r2, [r3, #36]    ; 0x24
    version = readl(SUNXI_SRAMC_BASE + 0x24) >> 16;
42e01154:    e5932024     ldr    r2, [r3, #36]    ; 0x24
42e01158:    f57ff05f     dmb    sy
    clrbits_le32(SUNXI_SRAMC_BASE + 0x24, (1 << 15));
42e0115c:    e5932024     ldr    r2, [r3, #36]    ; 0x24
42e01160:    e3c22902     bic    r2, r2, #32768    ; 0x8000
42e01164:    e5832024     str    r2, [r3, #36]    ; 0x24
#if defined CONFIG_MACH_SUN6I || \
    defined CONFIG_MACH_SUN7I || \
    defined CONFIG_MACH_SUN8I || \
    defined CONFIG_MACH_SUN9I
    /* Enable SMP mode for CPU0, by setting bit 6 of Auxiliary Ctl reg */
    asm volatile(
42e01168:    ee110f30     mrc    15, 0, r0, cr1, cr0, {1}
42e0116c:    e3800040     orr    r0, r0, #64    ; 0x40
42e01170:    ee010f30     mcr    15, 0, r0, cr1, cr0, {1}
#if defined CONFIG_MACH_SUN6I || defined CONFIG_MACH_SUN8I_H3
    /* Enable non-secure access to some peripherals */
    tzpc_init();
#endif

...

最近编辑记录 QbasicJacky (2020-06-04 10:03:14)