AnsweredAssumed Answered

imx6d boot fail with emmc 5.0

Question asked by Allen Kim on Nov 30, 2016
Latest reply on Nov 30, 2016 by igorpadykov

Dear all,

 

Our customer uses eMMC5.0 device. ( IMX6D , android 5.0  , sandisk emmc sdin9dw4-16g  ) 

we already modified android source ( mmc.c file  : card->ext_csd.rev )

 

first sample is ok , mfgtool downloading is ok ,  android boot is ok

 

our customer made almost 1k board

1st : 360 ea board : 27 ea board has problem

2nd : 300 ea board : 6 ea board has problem , customer changed SMT factory

3rd : 500 ea board : around 10 ea

 

  • problem 

board didn't boot ( uboot message is not shown  ) , not always can't boot , sometime board can boot ok 

approximately 1 time can't boot ( total 10 times tried ) , but boot fail is not regular ( randomly )

 

  • they think problem follow CPU IC

1 bad cpu reball to normal board  --> not boot

2 new cpu swapped on problem board  -> OK boot

 

  • I guess below first action is not done in problem board  ( therefore ram initialize is fail and uboot message is not displayed )

 

        booting process

  1. boot rom read DCD table from emmc
  2. boot rom initilize RAM with  DCD table 
  3. boot rom copy uboot binary to ram from emmc
  4. uboot message display on serial terminal

 

my Question

is there any compatibility with emmc 5.0 device ? they use sandisk .

 

 

scope picture 

1 is POR , 2 is SD4_DATA0

abnormal boot 

 

normal boot

 

 

May I have advice?

 

Best Regards,

Outcomes