AnsweredAssumed Answered

Boot from fuses for eMMC

Question asked by jsmith883 on Aug 27, 2018
Latest reply on Sep 4, 2018 by igorpadykov



I am trying to boot from fuses on an eMMC, but something is not working right.  The eMMC is is on SD4, 8-bit bus width.  Before blowing the fuses, I was booting from GPIOs on the same eMMC.  The SBMR register was reading 0x5870.  I then set the fuses by the following command:


echo 0x5870 > /sys/fsl_otp/HW_OCOTP_CFG5

echo 0x10 > /sys/fsl_otp/HW_OCOTP_CFG6


Once  I reset the board, the board no longer boots.  When I look at the registers now the SBMR is reading 0x0, and the OCOTP_CFG5 is reading 0x5870.  OCOTP_CFG6 is reading 0x10.  SBMR2 is reading 0x71.


However, if I plug in the OTG USB, the manufacturing tool will boot the board immediately, as if it's configured for serial download.  Any idea why this is not working correctly?