topic Re: imx_rngc Can't get interrupt working error in i.MX Processors

imx_rngc Can't get interrupt working error

JohnKlug — Mon, 13 Nov 2023 20:43:39 GMT

I am working on a new i.MX6ULL project, and noticed this in the boot of the device:

[ 3.880499] genirq: Flags mismatch irq 59. 00000004 (2284000.rng) vs. 00000004 (2284000.rng)
[ 3.908114] imx_rngc 2284000.rng: Can't get interrupt working.
[ 3.914004] imx_rngc: probe of 2284000.rng failed with error -16

I did not change the imx_rngc from this file:

https://github.com/Freescale/linux-fslc/blob/5.10.x%2Bfslc/arch/arm/boot/dts/imx6ull.dtsi#L71

To me, -16 implies some other driver already had interrupt 6?

rngb: rng@2284000 { compatible = "fsl,imx6ull-rngb", "fsl,imx25-rngb"; reg = <0x02284000 0x4000>; interrupts = <GIC_SPI 6 IRQ_TYPE_LEVEL_HIGH>; clocks = <&clks IMX6UL_CLK_DUMMY>; }; ./soc/bus@2200000/rng@2284000/interrupts: 00000000: 00000000 00000006 00000004

I have dumped every "interrupts" property in device tree and cannot find another 00000006 value. So why is this happening?

Re: imx_rngc Can't get interrupt working error

Harvey021 — Thu, 16 Nov 2023 06:50:26 GMT

From the err log, it seems like the issue with the driver code change, or you can have a check the /proc/interrupts, and refer to GitHub - nxp-imx/linux-imx at lf-5.10.y

Regards

Harvey

Re: imx_rngc Can't get interrupt working error

JohnKlug — Mon, 27 Nov 2023 23:28:00 GMT

This is /proc/interrupts:

bash# cat /proc/interrupts CPU0 17: 2443 GPC 55 Level i.MX Timer Tick 18: 0 GPC 94 Level arm-pmu 19: 17 GPC 13 Level 20: 5 GPC 15 Level bch 21: 0 GPC 32 Level 200c000.spi 22: 53 GPC 26 Level 2020000.serial 33: 0 GPC 120 Level 20b4000.ethernet 34: 0 GPC 121 Level 20b4000.ethernet 35: 0 GPC 80 Level 20bc000.watchdog 41: 0 GPC 20 Level caam-snvs 42: 0 GPC 19 Level rtc alarm 47: 0 GPC 2 Level sdma 48: 450 GPC 43 Level 2184000.usb 49: 0 GPC 42 Level 2184200.usb 50: 0 GPC 118 Level 2188000.ethernet 51: 0 GPC 119 Level 2188000.ethernet 52: 173 GPC 22 Level mmc0 53: 334 GPC 23 Level mmc1 54: 81 GPC 38 Level 21a8000.i2c 57: 0 GPC 27 Level 21e8000.serial 58: 0 GPC 28 Level 21ec000.serial 59: 0 GPC 29 Level 21f0000.serial 60: 0 GPC 46 Level dcp-vmi-irq 61: 0 GPC 47 Level dcp-irq 63: 1 GPC 6 Level 83: 0 gpio-mxc 19 Edge 21e8000.serial

GPC 6 appears to have no driver, but the CPU appears to be interrupted one time? What driver code change are you referring? Your link points to the source base, not a particular change.

bash# pwd /proc/device-tree/soc/bus@2200000/rng@2284000 bash# xxd -g4 interrupts 00000000: 00000000 00000006 00000004 ............

Re: imx_rngc Can't get interrupt working error

Harvey021 — Wed, 29 Nov 2023 08:18:44 GMT

This irq should have been registered, refer to this as attached. Check the code again and add printing in __setup_irq

Regards

Harvey

Re: imx_rngc Can't get interrupt working error

JohnKlug — Mon, 19 Feb 2024 17:46:00 GMT

I looked at this repository:
imx-rng from kernel.org

By using the imx-rng driver from kernel.org from commit 70564215ad927588dbea30472624cfd9e79d7c36 the issue went away, and the interrupt is properly allocated.