How to boot TDA2 from eMMC whether SD card is inserted or not?

Kevin Tsai

Prodigy 210 points

Other Parts Discussed in Thread: TDA2

Hi,

I boot TDA2 EVM from eMMC.

In file "uenv-emmc.txt", I have to define "root".

But something make me confused.

If SD card is inserted while booting, it will be defined as /dev/mmcblk0 and eMMC will be defined as /dev/mmcblk1.

If SD card is not inserted while booting, eMMC will be defined as /dev/mmcblk0.

How to define "root" if I want to boot from eMMC whether SD card is inserted or not?

Or I can fix eMMC as /dev/mmcblk0? And how to do it?

Thanks,

Kevin Tsai

over 9 years ago

0 Yordan Kamenov over 9 years ago

TI__Mastermind 42515 points

Hi Kevin,

I have forwarded your question to VisionSDK expert.

Regards,
Yordan

0 Ravi B over 9 years ago in reply to Yordan Kamenov

TI__Expert 7885 points

Kevin

Please provide the details of kernel release version you are using.

In linux kernel, eMMC is enumarated as the mmcblk0 and SD card as mmcblk1.

Regards

Ravi

0 Kevin Tsai over 9 years ago in reply to Ravi B

Prodigy 210 points

Hi Ravi,

Following is my Linux kernel version:
Linux dra7xx-evm 3.14.63-00013-gcb5f01e-dirty #11 SMP PREEMPT Wed Mar 15 11:40:54 CST 2017 armv7l GNU/Linux
BTW, where can I verify the enumaration of eMMC?

Thanks,
Kevin

0 Ravi B over 9 years ago in reply to Kevin Tsai

TI__Expert 7885 points

Kevin

The mmcblk0 or mmcblk1 depends on order in which the devices are enumerated and valid device found.

Another option is use UUID (Universally unique identifier), refer to TI-release, Check u-boot scripts, environment variables args_mmc, which setups the UUID for specific mmc boot partition.

# part uuid mmc 0:2 uuid

# run args_mmc

# pri boot_args

Regards

Ravi

Processors

Processors forum

How to boot TDA2 from eMMC whether SD card is inserted or not?