linux interrupt time

[2548903578]

Hi,everyone

  When I use imx6sx to configure the interrupt, the external will trigger an interrupt every 20ms, but the interrupt is not entered immediately after the interrupt is triggered, and there will be a certain delay. This delay time is about 10us. The problem now is that it is okay if the delay is 10us each time, but I found that the time of each entry interrupt is not fixed, sometimes it is long and sometimes short. There will be a certain error in this way. Does anyone know how to solve this problem? We are expecting a reply.

[igorpadykov]

Hi zxs

one can try fiq or rt patches or process interrupt on m4

https://community.nxp.com/t5/i-MX-Processors-Knowledge-Base/i-MX6-AVB-Demo-Implementation/ta-p/11270...

https://community.nxp.com/t5/i-MX-Processors/How-to-port-RTLinux-on-iMX6-board/td-p/380941

or "Real-Time Edge Software"

https://www.nxp.com/design/software/development-software/real-time-edge-software:REALTIME-EDGE-SOFTW...

Best regards
igor

[2548903578]

Hi,igorpadykov

 Real-Time Edge Software does not support imx6sx platform, only imx6ull.

• LS1046A: Layerscape® 1046A and 1026A Processors
• i.MX6ULL: i.MX 6ULL Single-Core Processor with Arm® Cortex®-A7 Core
• LS1028A: Layerscape® 1028A Applications Processor
• i.MX8MMINI: i.MX 8M Mini - Arm® Cortex®-A53, Cortex-M4, Audio, Voice, Video
• LX2160A: Layerscape® LX2160A, LX2120A, LX2080A Processors
• LS1043A: Layerscape® 1043A and 1023A Processors
• IMX8MPLUS: i.MX 8M Plus – Arm® Cortex®-A53, Machine Learning, Vision, Multimedia and Industrial IoT
• LS1021A: Layerscape® 1021A Dual-Core Processor with LCD Controller
• LS1012A: Layerscape® 1012A Low Power Processor

[igorpadykov]

you can port it yourself using i.MX6ULL as example.

Best regards
igor

[2548903578]

Hi，igorpadykov 

Can rt patches make the interruption time stable? I tested it and found that it is not as good as not adding it. We are using pin input interrupt, does fiq support it? Our m4 can only open one interrupt, so no other interrupts can be used.

[2548903578]

I played the rt package and still the same situation.