AM335x MMC1 boot does not detect eMMC

Joe Cho

Prodigy 150 points

Other Parts Discussed in Thread: AM3358, AM3352

Dear all:

We made a custom board based on the BeagleBone datasheet.

The mmc0 is build to a micro SD socket.

the mmc1 is build to a 2G emmc.

However, MMC0 can booting from MLO > u-boot > linux.

But the mmc1 is not working when power on even the mmc1 is already partitioned

Here's my u-boot log (using mmc0 boot):

U-Boot# ls mmc 1
    99976   mlo
   379428   u-boot.img
       26   uenv.txt
            app/
            docs/
            drivers/
    41174   license.txt
      292   readme.md
    16827   start.htm
      223   autorun.inf
       30   id.txt
4385024   uimage

9 file(s), 3 dir(s)

U-Boot# ls mmc 1:2
<DIR>       4096 .
<DIR>       4096 ..
<DIR>      16384 lost+found
<DIR>       4096 bin
<DIR>       4096 sbin
<DIR>       4096 media
<DIR>       4096 home
<DIR>       4096 mnt
<DIR>       4096 usr
<DIR>       4096 boot
<DIR>       4096 etc
<DIR>       4096 tmp
<DIR>       4096 run
<DIR>       4096 var
<DIR>       4096 lib
<DIR>       4096 sys
<DIR>       4096 proc
<DIR>       4096 dev
U-Boot#

It's output CCCCCCCCCCCCCC

I think the mmc1 pin define is correct.

MMC1_0~7 pin is U7 V7 R8 T8 U8 V8 R9 T9 ,

CLK: U9

CMD: V9

CLK: T13

And we also have the boot mode selection jumper for boot debug.

http://processors.wiki.ti.com/index.php/File:BootMode.JPG

The jumper is now setting sysboot[4:0] 11100

After the each debug and try, AM335 still not booting from mmc1.

However, The main system will put into the mmc1 (emmc)

If the AM335x an not booting from mmc1, our system will not work anymore.

Thank you everyone if you have any idea or suggestion.

BRs, Joe.

over 11 years ago

0 Biser Gatchev-XID over 11 years ago

TI__Guru**** 393215 points

Hi Joe,

Joe Cho said:
MMC1_0~7 pin is U7 V7 R8 T8 U8 V8 R9 T9
CLK: U9

CMD: V9

CLK: T13

What is this CLK signal on pin T13?

0 Julien Erdogan over 11 years ago

Intellectual 420 points

I made a custom BBB too and I had the same problem.

Did you had the EEPROM ? The device tree overlay is loaded by U-boot depending on what's written in the EEPROM.

If you use a newer kernel, the EEPROM is bypassed by the U-boot and the device tree loaded is the one of the BBB.

I hope that this will help you.

Julien

0 Joe Cho over 11 years ago in reply to Biser Gatchev-XID

Prodigy 150 points

Dear Biser :

I asked the HW develpoer, the T13 signal is set 0 now.

Does it matter for detecting emmc when booting?

And I tried to find the hw design datasheet.

there is a little diffent between BBB_SRM and BB_SCH

1. https://github.com/CircuitCo/BeagleBone-Black/blob/master/BBB_SRM.pdf?raw=true

2. ttps://github.com/CircuitCo/BeagleBone-Black/blob/master/BBB_SCH.pdf?raw=true

Our HW develpoer follows the 2 referenced layout.

(R14 connects to emmc_reset, and T13 now set 0)

1. In BBB(am3358) SRM:

am335x T13 connects to emmc_reset.

2. In BBB(am335x) SCH:

am335x R14 connects to emmc_reset, and T13 connects to GPIO 1_16.

If I set T13 to 1, the am3352 will detect emmc?

0 Biser Gatchev-XID over 11 years ago in reply to Joe Cho

TI__Guru**** 393215 points

To access the eMMC the emmc_reset must be high when the AM335X comes out of reset. For your information this is the official location of the Beaglebone Black design files: http://elinux.org/Beagleboard:BeagleBoneBlack#Hardware_Files

0 Joe Cho over 11 years ago in reply to Julien Erdogan

Prodigy 150 points

Dear Julien:

Yes, I had an EEPROM for board description . And there is the same EEPROM and data inside (we copied it from BBB).

I think AM335x together with currently EEPROM works fine.

I am still trying. Hope you can also get the soultion.

BRs , Joe.

0 Joe Cho over 10 years ago in reply to Biser Gatchev-XID

Prodigy 150 points

Dear Biser:

Thank you.

I've checked the emmc_reset pull to high .

It's very hard to check or debug .

We've already checked pins and layout.

Currently, our board can't access emmc when 335x booting.

Do you have any suggesstion ?

0 Biser Gatchev-XID over 10 years ago in reply to Joe Cho

TI__Guru**** 393215 points

I do not understand. You can access eMMC when booting from SD card, but you cannot boot from eMMC, is this correct?

0 Joe Cho over 10 years ago in reply to Biser Gatchev-XID

Prodigy 150 points

Dear Biser:

We found the problem. Finally, it can boot from eMMC.

Many thanks for your help.

BRs, Joe.

0 Ben Leedy over 10 years ago in reply to Joe Cho

Prodigy 10 points

Joe,

Would you mind sharing the solution to your problem? We are running into similar difficulties. Thanks.

0 Paul Chacko over 9 years ago in reply to Joe Cho

Intellectual 613 points

Dear Joe Cho,

We are also facing the same problem. Could you please let us know how did you resolve it?

Thanks and regards,
Paul

0 Paul Chacko over 9 years ago in reply to Paul Chacko

Intellectual 613 points

Dear All,

We have solved the issue. For others' benefit I am putting the resolution we had in our design.

By default, boot ROM checks the data on the GPMC_AD[0 :3]pins of the processor. We had chosen another pinmuxing option suggested by pin muxing utility.

After connecting the GPMC_AD0 pin to MMC1_D0, it is working.

Regards,

Paul

0 veera anjaneyulu over 8 years ago in reply to Joe Cho

Expert 1920 points

Hi Joe Cho,

we are facing same issue? can briefly explain how to flash images from sdcard to emmc.Actually we are using same interface mmc0 for sdcard and emmc.Is it possible to load images from sd card to emmc.

Thanks
veera

0 Joe Cho over 8 years ago in reply to veera anjaneyulu

Prodigy 150 points

Dear verra anjaneyulu:
actually, we made the jumper [8 pins for different booting mode change], so that we can either boot from sd card or emmc. You have to refer the Hardware pins muxing to determine the pin layout.
Also , you can reference the suggesstion form Paul Chacko experience. I think it's better.

BRs, Joe

0 veera anjaneyulu over 8 years ago in reply to Paul Chacko

Expert 1920 points

Dear Joe Cho,
we are also facing same the problem.Could you please let us know how did you resolve it?

Thanks & Regards
veeranjaneyulu

0 veera anjaneyulu over 8 years ago in reply to Joe Cho

Expert 1920 points

Dear Joe,
In our case emmc(8bit) and sdcard (4bit) are connected to mmc0 interface only.So we flashed uboot and kernel images through uart booting.After that how to flash the uboot and kernel images to emmc?Is any body resolved the issue?can guide me.

Thanks & Regards

veera

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AM335x MMC1 boot does not detect eMMC