LS1043a U-Boot LPUART Peripheral

[zach_ferree]

How do I Enable LPUART's 1 and 2 so I can use them to talk to some peripherals in U-Boot.

I tried enabling the Freescale LPUART support in my defconfig using make menuconfig but now I get compile errors saying that I have undefined references to devfdt_get_addr so i tried enabling fdt_serial and updating my .dts to enable the lpuarts but i am still getting the same build errors with no change.

[yipingwang]

Hello Zach Ferree,

Please refer to configs/ls1043aqds_lpuart_defconfig

Please define the following in u-boot configuration file.

CONFIG_FSL_LPUART=y

CONFIG_SYS_EXTRA_OPTIONS="LPUART"

CONFIG_DEFAULT_DEVICE_TREE="fsl-ls1043a-qds-lpuart"

For dts configuration, please refer to arch/arm/dts/fsl-ls1043a-qds-lpuart.dts

/dts-v1/;

#include "fsl-ls1043a-qds.dtsi"

/ {

       chosen {

               stdout-path = &lpuart0;

       };

};

Thanks,

Yiping

[zach_ferree]

yipingwang‌

I did what you suggested and I am still getting the following compile time error.

"build/workspace/sources/u-boot-qoriq/drivers/serial/serial_lpuart.c:417: undefined reference to `devfdt_get_addr'"

do you have any sugesstions on how to fix this?

do I need to enable FDT_SERIAL in the defconfig? am I missing a dependency in one of my .conf files?

[yipingwang]

Hello Zach Ferree,

Which version LSDK are you using now? Would you please send your modified configuration file

to me to do more verification?

Thanks,

Yiping

[zach_ferree]

Yiping,

I am using 19.04 of the LSDK

see attached for the modified copy of the defconfig I am using

[yipingwang]

Hello Zach Ferree,

      Is it possible to use NOR flash u-boot? If yes, please create u-boot configuration file based on the attached configuration file.

Thanks,

Yiping

[zach_ferree]

Yiping,

Unfortunately I am unable to use NOR flash as I am developing a board with only MMC.

Do you think the issue has to do with using UART0 as the serial interface with the SYS_NS16550 driver along side the FSL_LPUART driver?

Do you know if the SYS_NS16550 driver is using the device tree model or the older model?

Thanks,

Zach

[yipingwang]

Hello Zach,

SYS_NS16550 driver is used , if enable CONFIG_SPL_SERIAL_SUPPORT in the configuration file.

Thanks,

Yiping

[zach_ferree]

Yiping,

I am still having issues compiling with that enabled.

The compiler error I am getting is

"u-boot-qoriq/drivers/serial/serial_lpuart.c:417: undefined reference to `devfdt_get_addr'"

I believe this to be a linker error, do you know how to verify that the compiler is using the correct "built-in.o" files when linking?

devfdt_get_addr is defined in drivers/core/fdtaddr.c and that is always compiled according to drivers/core/Makefile.

Thanks,

Zach

[yipingwang]

Hello Zach,

Please define the following options in u-boot configuration file.

CONFIG_FSL_LPUART=y
CONFIG_SPL_DM=y
CONFIG_SPL_OF_LIBFDT=y
CONFIG_SPL_OF_CONTROL=y

Thanks,

Yiping

[zach_ferree]

Yiping,

Adding the config items you listed to my configuration caused the following compile time error

"/u-boot-qoriq/env/mmc.c:42: undefined reference to `blk_get_device_by_str'"

taking a look at what file has the definition for blk_get_device_by_str  i found that it was disk/part.c

in order to get that compiling into the image i need to define CONFIG_PARTITIONS in my defconfig, the odd part is that it is already in my defconfig and i was able to confirm that it was getting compiled by adding a "#error"  right above the definition of blk_get_device_by_str. so there is some issue where it is getting built but the linker is unable to link it.

Any suggestions?

thanks,

Zach

[yipingwang]

Hello Zach,

Please disable CONFIG_SPL_OF_CONTROL=y in u-boot configuration file.

Thanks,

Yiping

[zach_ferree]

yipingwang‌,

do you have anything else for me to try to get the ability to use the lpuart's while having UART0 as my console?

Thanks,

Zach

[zach_ferree]

Yiping,

I disabled CONFIG_SPL_OF_CONTROL in my u-boot configuration file.

i get an undefined reference error of the following "u-boot-qoriq/drivers/mmc/fsl_esdhc.c:1390: undefined reference to `fdtdec_get_int'"

Taking a look at the Makefile in the lib folder it should be either the CONFIG_FIT or the CONFIG_SPL_OF_CONTROL define that makes fdtdec_common.c get compiled. CONFIG_FIT will do it only if CONFIG_SPL_BUILD is not defined, I do not have CONFIG_SPL_BUILD defined in my defconfig so it should be compiling fdtdec_common.

putting in a #error does cause a compile time error so it is getting compiled but it seems to not be getting linked.

Thanks,

Zach

[zach_ferree]

In this case i am not using lpuart0 as stdout, i am using it to communicate with a peripheral device, does that change anything?