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mmc0: error -84 whilst initialising MMC card

Question asked by wen zhu on Aug 5, 2015
Latest reply on Jun 6, 2017 by Marco Cavallini


     I met a problem about the EMMC:

     When the unit bootup from the EMMC,it would report this error:

       mmc0: error -84 whilst initialising MMC card

  Follow the source code,I found when the emmc tried to send this command:

#define MMC_ALL_SEND_CID          2   /* bcr                     R2  */

   it would met error.


   when we tried to init the EMMC,we need tried to Fetch CID from card,but it couldnot fetch it:


  * Fetch CID from card.


  if (mmc_host_is_spi(host))

     err = mmc_send_cid(host, cid);


     err = mmc_all_send_cid(host, cid); ---> process this funtion,it would report error -84

     printk("%s,[%d],err =%d \n",__func__,__LINE__,err);


  if (err)

      goto err;


   Do you know why ? and how to solve this problem? Thanks very much in advance.



   1.My BSP version is :android 4.0.4 (android-13.5.0-ga.01);

   2.The kernel version is:Linux 3.0.35;

   3.the CPU is:CPU identified as i.MX6SoloLite, silicon rev 1.2

   3.Here is the mmcinfo:  

MX6Sl Z970B U-Boot > mmc dev 1

mmc1(part 0) is current device

MX6Sl Z970B U-Boot > mmcinfo


Manufacturer ID: 11

OEM: 100

Name: 008GE

Tran Speed: 25000000

Rd Block Len: 512

MMC version 4.0

Clock: 52000000

High Capacity: Yes

Capacity: 7818182656 Bytes

Bus Width: 4-bit DDR

Current Partition for boot: Not bootable

MX6Sl Z970B U-Boot >

4.For more informations,please refer to the attachment file.


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