Timer 如何使计时器irq在QEMU上工作（-machine virt-cpu cortex-a57）

我正在QEMU（-machine virt-cpu cortex-a57）上尝试定时器中断，但直到现在仍然失败。我有几个问题需要你的建议，非常感谢你的帮助

[已修复]问题已在（提交）中修复 7aaa433576602b93d426f63b1a8a9fe473a52506）。我能得到正确的答案 基于异常（使用GDB）的计时器IRQ。根本原因是缺少GIC设置

有没有简单的例子供我参考？或者我应该在哪里问这个问题

在我目前的研究中，有人可以给我一些建议（提交b72c6a8cc7033a4fed89b57f75826d201466179f）？ 目前的状态是，我们可以看到CNTV_CTL_EL0:bit2（ISTATUS）发生变化，但没有调用irq_中断句柄回调函数，我们也没有观察到ISR_EL1中的任何变化（没有检测到irq中断挂起）

2-1。我更新程序，添加gic配置。但还是不行。我需要帮助。（提交80CDCD3AEC0942B5AF28ACAF350C136ABF1A730）

程序/日志如下所示

$ make run
qemu-system-aarch64 -machine virt -cpu cortex-a57 -nographic -kernel kernel.elf

/* init_gicd( ) */
REG_GIC_GICD_CTLR: 0x00000000 08000000 = 0x00000000 00000000
Write REG_GIC_GICD_ICENABLER:
0x00000000 08000180 = 0x00000000 FFFFFFFF
0x00000000 08000184 = 0x00000000 FFFFFFFF
Write REG_GIC_GICD_ICPENDR:
0x00000000 08000280 = 0x00000000 FFFFFFFF
0x00000000 08000284 = 0x00000000 FFFFFFFF
REG_GIC_GICD_IPRIORITYR:
0x00000000 08000400 = 0x00000000 FFFFFFFF
0x00000000 08000404 = 0x00000000 FFFFFFFF
0x00000000 08000408 = 0x00000000 FFFFFFFF
0x00000000 0800040C = 0x00000000 FFFFFFFF
0x00000000 08000410 = 0x00000000 FFFFFFFF
0x00000000 08000414 = 0x00000000 FFFFFFFF
0x00000000 08000418 = 0x00000000 FFFFFFFF
0x00000000 0800041C = 0x00000000 FFFFFFFF
0x00000000 08000420 = 0x00000000 FFFFFFFF
0x00000000 08000424 = 0x00000000 FFFFFFFF
0x00000000 08000428 = 0x00000000 FFFFFFFF
0x00000000 0800042C = 0x00000000 FFFFFFFF
0x00000000 08000430 = 0x00000000 FFFFFFFF
0x00000000 08000434 = 0x00000000 FFFFFFFF
0x00000000 08000438 = 0x00000000 FFFFFFFF
0x00000000 0800043C = 0x00000000 FFFFFFFF
REG_GIC_GICD_ITARGETSR:
0x00000000 08000820 = 0x00000000 00000000
0x00000000 08000824 = 0x00000000 00000000
0x00000000 08000828 = 0x00000000 00000000
0x00000000 0800082C = 0x00000000 00000000
0x00000000 08000830 = 0x00000000 00000000
0x00000000 08000834 = 0x00000000 00000000
0x00000000 08000838 = 0x00000000 00000000
0x00000000 0800083C = 0x00000000 00000000
REG_GIC_GICD_ICFGR:
0x00000000 08000C04 = 0x00000000 00000000
0x00000000 08000C08 = 0x00000000 00000000
0x00000000 08000C0C = 0x00000000 00000000
REG_GIC_GICD_CTLR: 0x00000000 08000000 = 0x00000000 00000001

/* init_gicc( ) */
GICC_CTLR: 0x00000000 08010000 = 0x00000000 00000000
REG_GIC_GICC_PMR: 0x00000000 08010004 = 0x00000000 000000FF
REG_GIC_GICC_BPR : 0x00000000 08010008 = 0x00000000 00000000
REG_GIC_GICC_EOI : Clear all of the active interrupts
REG_GIC_GICC_CTLR : 0x00000000 08010000 = 0x00000000 00000001

/* gicd_enable_int(27) */
REG_GIC_GICD_ISENABLER: 0x00000000 08000100 = 0x00000000 0800FFFF

/* Virtual Timer config */
CurrentEL = 0x00000000 00000004    /* EL1 */
DAIF = 0x00000000 000003C0         /* DAIF bits are set */
CNTV_CTL_EL0 = 0x00000000 00000000
Disable the timer, CNTV_CTL_EL0 = 0x00000000 00000000 /* Clear bits of ENABLE/IMASK */
CNTFRQ_EL0 = 0x00000000 03B9ACA0   /* frequency of the system counter = 62.5MHz */ 
CNTVCT_EL0 = 0x00000000 000242C5   /* current 64-bit virtual count value */
Set it as next 1 sec, CNTV_CVAL_EL0 = 0x00000000 03BBEF65 /* set compare value */
Enable the timer, CNTV_CTL_EL0 = 0x00000000 00000001  /* Set bit ENABLE */
Enable IRQ, DAIF = 0x00000000 00000340  /* Clear IRQ mask bit */

/* we observe the CNTVCT_EL0 and CNTV_CTL_EL0 */
/* if time up, CNTV_CTL_EL0[2] = 1 */
CNTVCT_EL0 = 0x00000000 000390CA, CNTV_CTL_EL0 = 0x00000000 00000001
CNTVCT_EL0 = 0x00000000 0003D41F, CNTV_CTL_EL0 = 0x00000000 00000001
...
/* time up, CNTV_CTL_EL0[2]: ISTATUS = 1*/
CNTVCT_EL0 = 0x00000000 03BCE5C4, CNTV_CTL_EL0 = 0x00000000 00000005
SPSR_EL1 = 0x00000000 00000000
ISR_EL1 = 0x00000000 00000000
/* But the irq_handler doesn't be called and ISR_EL1[7] = 0 */
/* there is no IRQ interrupt pending detected */
QEMU: Terminated

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1.以下是来自ARM Trusted固件的[1]，它使用定时器相关寄存器生成时间IRQ并处理它。2.与每个步骤共享您的输出，以显示计时器是如何失败的。[1] ：谢谢你的建议。我试试看。谢谢大家。问题已经解决，我可以根据计时器IRQ获得正确的异常。