[#3947] BF54x SDH/MMC not functional

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[#3947] BF54x SDH/MMC not functional

Submitted By: Michael Hennerich

Open Date

2008-02-29 08:20:41     Close Date

2008-03-18 06:53:54


Medium High     Assignee:

Vivi Li


Closed     Fixed In Release:


Found In Release:

N/A     Release:


N/A     Board:



BF548     Silicon Revision:

Is this bug repeatable?:

Yes     Resolution:


Uboot version or rev.:

    Toolchain version or rev.:

App binary format:


Summary: BF54x SDH/MMC not functional



On 2008R1 as well as on svn trunk BF54x SDH driver is not functional.


Quick hint: NFC/NAND mtd driver needs to turned off, because SDH and NFC share the   same DMA channel.






--- Vivi Li                                                  2008-03-10 00:05:22

What did you mean by not functional? For the past weeks I reported serveral bugs

of SDH. Please refer to bug 3925/3960/3961. NAND mtd driver is default to be

enabled when I test.

Attached are the latest auto test result and the config file.


--- Michael Hennerich                                        2008-03-10 07:43:52

Hi Vivi,


>What did you mean by not functional?


None of the card gets recognized.

And I don't get this kmesg line:


mmcblk0: mmc0:e624 SD01G 992000KiB

mmcblk0: p1 p2


>NAND mtd driver is default to be

enabled when I test.


Impossible - also your config has NFC NAND support turned off.


I tested here using your config file - no difference.

The only difference here - I test on the latest BF548-Ezkit using Silicon Rev


As soon I get my old EZkit back I will run the image I build there.




--- Vivi Li                                                  2008-03-10 22:38:51

First, have you soldered a resistor to 548 borad? SDH can't detect inserted card

without adding this resistor. Roy ever gave a comment about this in



Second, I'm using board version 1.1 for testing.


--- Michael Hennerich                                        2008-03-11 06:22:26



I would expect that on the 1.3 Rev of the BF548-EZkit, I don't need to do any

HW modifications. In case there was issue on the 1.1 Rev, this should have been

reported to the tools group.


I also expect that you test on the latest 1.3 Rev. of the board, because this

is the board everyone can buy / uses.


Do you have more information about the HW mods on your board?




--- Vivi Li                                                  2008-03-12 04:35:07



I have tried SDIO on 1.3 Rev of BF548-EZkit and it failed to detect MMC card.

I'll solder a resistor to it and try again.

We only got one board of 1.3 Rev of BF548-EZKIT for developers, so now we are

using Rev. 1.1 for testing.




--- Vivi Li                                                  2008-03-12 06:27:06

For BF548-EZKIT Rev. 1.3, I solder a 10k resistor to it and MMC/SD cards can be



--- Michael Hennerich                                        2008-03-12 08:15:26



Thanks - to which signal / pin did you solder the resistor?




--- Sonic Zhang                                              2008-03-12 22:21:12

Robin, do you know whom in the hardware team can we report this board bug to?


--- Vivi Li                                                  2008-03-12 23:41:06



The 10K resistor is soldered between two pins of SD MEMORY CONNECTOR J5:

3rd pin(the one connected to R170) and 5th pin(near C132) from right side.

On schematic, they are pin 2 and 4 of J5.




--- Michael Hennerich                                        2008-03-13 08:17:10

Ok - I looked a bit into the driver.


ios->bus_mode == MMC_BUSMODE_OPENDRAIN

The driver sets SD_CMD_OD in the SDH_PWR_CTL register.


This turns the CMD pin into an Open Drain output - however we don't have a Pull

Up on the board.


The VDSP drivers doesn't set SD_CMD_OD, so the issue for them goes unnoticed.

If I don't set SD_CMD_OD the driver works fine.


The question now - should we workaround a HW modification by simply not setting


I don't have a SDIO spec at hand - so I can't tell what exactly is the story

behind CMD Open Drain.




--- Sonic Zhang                                              2008-03-18 00:12:10

Fixed by Michael.


--- Vivi Li                                                  2008-03-18 06:53:54

So close it.












File Name     File Type     File Size     Posted By

config.sdiommc    text/plain    31074    Vivi Li

sdiommc_test_log    text/plain    26409    Vivi Li