How to know the irq number for the UART3 module on i.MX6Q

[yinliangren]

   I'd like to set IRQ to CPU1 on i.MX6Q sabresd board like : 

                                   echo 2 > /proc/irq/irqnumber/smp_affinity

 But I didn't find the irq number for UART3 module, could somebody help me? 

BTW, the BSP version is 5.10.72_2.2.0.

[Yuri]

@yinliangren 
Hello,

   According to Table 3-1 (Arm Cortex A9 domain interrupt summary) of i.MX 6Dual/6Quad Reference Manual (Rev. 6, 05/2020) IRQ = 60 for  UART3 interrupt request.

Regards,
Yuri.

[yinliangren]

Hi Yuri,

   Thanks for your answer, but I haven't found the number 60 in /proc/irq/ as below:

root@imx6qsabresd:~# uname -a
Linux imx6qsabresd 5.10.72-lts-5.10.y+ga68e31b63f86 #1 SMP PREEMPT Tue Nov 23 06:02:20 UTC 2021 armv7l armv7l armv7l GNU/Linux
root@imx6qsabresd:~#
root@imx6qsabresd:~# ls /proc/irq/
100/ 291/ 72/
118/ 30/ 73/
123/ 31/ 74/
125/ 315/ 77/
147/ 32/ 78/
16/ 33/ 79/
17/ 34/ 80/
171/ 35/ 81/
178/ 51/ 82/
18/ 52/ 83/
181/ 57/ 84/
184/ 58/ 85/
19/ 62/ 86/
20/ 63/ 87/
21/ 64/ 88/
22/ 65/ 89/
221/ 66/ 90/
23/ 67/ 95/
24/ 68/ 96/
25/ 69/ default_smp_affinity
26/ 70/
28/ 71/

Could you tell me how to show 60 in /proc/irq/ ? Thanks a lot.

[yinliangren · Accepted solution]

I've got the number, it's not a constant number. The irq number showed up after I ran an application to open and use UART3.