How to enable UART2 in Linux on LX2160A?

[ZhaoZheng1]

Hi,

I'd like to enable both UART1 and UARAT2 in Linux on LX2160A.
kernel version: 5.15.71

configuration in dts, it seems ok.

Check UART control register, UART2 has not been enabled.
root@localhost:~# devmem2 0x21d0030 32
0x00000300
root@localhost:~# devmem2 0x21c0030 32
0x00000B01

May i have your comments?
Many thanks!

Zhao

[ZhaoZheng1]

BTW, I have a trial to modify the register of UARTCR to enable UART2, still not working..

[yipingwang · Accepted solution]

Please try below patch

https://patchwork.ozlabs.org/project/uboot/cover/1607490724-6447-1-git-send-email-vabhav.sharma@oss....

Then enable CONFIG_SERIAL_PROBE_ALL=y in lx2160ardb_tfa_defconfig after applying this patch.

[ZhaoZheng1]

Hi Yiping,

Thanks for your great help.

I checked the patch, it's about u-boot.
Does it mean enable UART2 in Linux should probe all UARTs in u-boot?

Thanks,

Zhao

[yipingwang]

Yes, you need to apply this patch in u-boot. Then check UART1 and UART2 in Linux.

[ZhaoZheng1]

That's make sense.

I just checked the patch already integrated into u-boot mainline at least in LF-5.15.y.

[yipingwang]

Please enable CONFIG_SERIAL_PROBE_ALL=y in lx2160ardb_tfa_defconfig after applying this patch.

We have verified this method in LSDK 21.08.

[ZhaoZheng1]

Thanks a lot, Yiping.

Regards,

Zhao