AM4378: Partitioning eMMC from U-boot

Jense Arntz

Intellectual 320 points

Part Number: AM4378

I have custom board AM437x_GP_EVM board that want to partition emmc on u-boot for booting from emmc.

But My emmc interface is using mmc 0

So Could I partition emmc on u-boot?

Thanks.

over 9 years ago

0 Dwarakesh Radhakrishnan over 9 years ago

Guru 13660 points

Hi Jense,

uboot is not capable of partitioning eMMC, since it is small and it does not have sufficient tools to partition.

But you can create an entire disk partitions, including the filesystems in PC and then flash the entire image in uboot to raw sectos of eMMC.

0 Jense Arntz over 9 years ago in reply to Dwarakesh Radhakrishnan

Intellectual 320 points

Hi Dwarakesh

Thanks for your quick reply.

Ok, I will try as you instructed above.

Then, How can I connect emmc to my pc?

Thanks.
Jense.

0 Dwarakesh Radhakrishnan over 9 years ago in reply to Jense Arntz

Guru 13660 points

Hi Jense,

You cannot connect eMMC to PC. What I meant is something like this, in Linux PC

# dd if=/dev/zero of=file.fs bs=1024 count=102400
# mkfs.fat file.fs
# mkdir /mnt/tmp
# mount file.fs /mnt/tmp/
# cp contents_in_first_partition /mnt/tmp (Here you would copy the MLO, uboot , boot scripts etc)
# sync
# umount /mnt/tmp

Copy the file.fs into SDCard and connect to the Board. In the uboot of AM437x:

# fatload mmc 1 1 0x80800000 file.fs (Assuming SDCard is mmc 1 and partition is 1 )
# mmc write 0 0x80800000 0x200 0xA00000 (Writing in eMMC, which is mmc 0. 0x200 since first 512 bytes of MBR. Also need to flash it)

This is an example. May not be all commands correct. You can do the same for ext4 fs which contains the filesystems. Easier would be to partition the eMMC from the Linux(AM437x) and program it.

0 Biser Gatchev-XID over 9 years ago

TI__Guru**** 393215 points

Please check processors.wiki.ti.com/.../Linux_Core_U-Boot_User's_Guide

0 Dwarakesh Radhakrishnan over 9 years ago in reply to Biser Gatchev-XID

Guru 13660 points

Hi Jense,

Yes as per Biser link, you can use GUID Partition Table. I was referring to the conventional partitioning and in the case of old uboot.

0 Jense Arntz over 9 years ago in reply to Dwarakesh Radhakrishnan

Intellectual 320 points

Thanks for your response.

Yes, I tried and I changed my idea for emmc.

I am going to boot from sd card on AM437x_GP_EVM.

What files should I put on SD card and How can I make it boot from sd card?

Thanks.
Jense.

0 Dwarakesh Radhakrishnan over 9 years ago in reply to Jense Arntz

Guru 13660 points

Hi Jense,

Please refer to the same link as Biser shared for SDCard boot: processors.wiki.ti.com/.../Linux_Core_U-Boot_User's_Guide

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AM4378: Partitioning eMMC from U-boot