UART output garbled

[caibai]

hi，

    i run FreeRTOS on cortex-M4 and linux on cortex-A9,when i run demo app <FreeRTOS_BSP_1.0.0_iMX6SX/examples/imx6sx_sdb_m4/demo_apps/low_power_imx6sx/periodic_wfi_qspi> and cortex-M4 uart garbled after linux startup,it seems that uart clock is change,what can i do?

[Carlos_Musich · Accepted solution]

Hi cai bai,

Sometimes there are problems in clock sync when A9 starts. Run your system and stop the bootloader, then apply the following commands and run your application.

env default -a

setenv fdt_file imx6sx-sdb-m4.dtb

setenv bootcmd "run m4boot;${bootcmd}"

setenv mmcargs "${mmcargs} uart_from_osc"

saveenv

Please let me know if it works.

Regards,
Carlos

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[caibai]

it work now ,thank you very much

[caibai]

i find that uart root clock will change from osc to PLL3 ,so when i get this change on cortext-M4, then reconfigure uart like

DbgConsole_Init(BOARD_DEBUG_UART_BASEADDR,80000000,115200);

but it also output garbled.

when are the clock init in linux