AM335x eMMC raw mode requirement

EB R.

Hello.

Section 26.1.7.5.3 of the AM335X Technical Reference Manual states:

The booting file is searched only in case of booting from a card. eMMC/eSD embedded memories only support raw mode

I don't understand why the AM335X would care or require this. It works fine for me when I tested the eMMC on MMC1 without raw mode, (ie partitioning it as FAT - like a SD card - and booting mlo/u-boot from it).

Can someone please if we really have to use raw mode? If so, what's behind this restriction?If not, why the statement in TRM?

Thanks

over 11 years ago

0 Biser Gatchev-XID over 11 years ago

TI__Guru**** 393215 points

This may be due to the fact that your eMMC responds to ROM code initialization like a card.

0 EB R. over 11 years ago in reply to Biser Gatchev-XID

Prodigy 20 points

Thanks, that makes sense. But what distinguishes or make the distinction between a eMMC from a regular MMC card in ROM initialization?

I looked at the ROM flowchart and all it says is "Row mode" detected? Yes -> Get Raw Data or No->Get Boot file - with a comment "The booting file is searched only in case of MMC/SD card"

So, how does ROM do this distinction? Any specific CMD protocol?

Thanks

0 Biser Gatchev-XID over 11 years ago in reply to EB R.

TI__Guru**** 393215 points

The ROM code is not public. The AM335X TRM has all the information that's available.

0 Tarun Kaushik over 9 years ago

Intellectual 270 points

Hello,

Can u help me in sharing the information how you have formatted the emmc !

thanks

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AM335x eMMC raw mode requirement