LayerscapeのトピックRe: LS1021ATWR - U-BOOT- UART - LPUART

LS1021ATWR - U-BOOT- UART - LPUART

zoranstoilov — Thu, 28 Jul 2016 16:18:20 GMT

Hi,

I have a LS1021atwr Rev2.0 connected with TWR-SER2. I want to use RS485 functionality of TWR-SER2.

But RS485 is connected to LPUART1 pins.

If I enable LPUART in "include/configs/ls1021atwr.h", the console from UART1/USB is gone and I can see it on LPUART1.

J19 and J20 before were shorting 2-3 when uart used and now they are shortening 1-2 when LPUART enabled.

My question is how to configure u-boot so I can have console and I can use LPUART1(/dev/ttyLP0)?

I have enabled ttyLP1 in device tree(&lpuart1) but I don't know if/where it is connected to TWR-SER2 board!?

I use SDK1.9 for u-boot building with sdk2.0 for openwrt rootfs and I boot from SD_CARD only.

Re: LS1021ATWR - U-BOOT- UART - LPUART

Pavel — Fri, 29 Jul 2016 03:57:18 GMT

Find the following setting in the u-boot configuration file for TWR-LS1021A board (ls1021atwr.h file)

#ifdef CONFIG_LPUART

#define CONFIG_EXTRA_ENV_SETTINGS \

"bootargs=root=/dev/ram0 rw console=ttyLP0,115200\0" \

"initrd_high=0xcfffffff\0" \

"fdt_high=0xcfffffff\0"

Have a great day,
Pavel Chubakov

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Re: LS1021ATWR - U-BOOT- UART - LPUART

zoranstoilov — Fri, 29 Jul 2016 07:22:57 GMT

I guess I was not clear in my question.

Before I had a ls1021a Rev1.0 and UART by default. The console was on ttyS0 and the connection to RS485 on TWR-SER2 board was ttyS1 and I used both. Now in ls1021a Rev2.0 the RS485 is connected to ttyLP0 and the console as well.

What to do in order to have RS485 and console on separate tty's?

I couldn't find where is ttyLP1 going from TWR-ls1021a reference manual which I could use as console.

Regards,

Zoran Stoilov