This might be a loooong shot in the dark, but... Many MMC/SD cards need to be fully reset, when left in an "undefined" state. This normally means power supply voltage (at SD card) must drop below 1.3V for a sizable (>100ms) time.
Do you have means to physically remove power to eMMC? Many eMMC chips don't have a usable Reset pin. HiH Mauro On 1/25/20 4:42 PM, Amarnath MB wrote: > Hi all, > > I working on a T1042RDB based custom board which has a 8GB eMMC (4bit mode) > on board. I was able to successfully boot 2019.07 uboot on my board from > NOR flash. > > After booting, mmcinfo command detects the on board eMMC and displays it's > properties. But when I issue mmcinfo command after soft reset through reset > command, it gives me mmc_init timeout error. > > After adding DEBUG and CONFIG_MMC_TRACE macros to my board header file, i > came to know that the eMMC fails to respond to CMD 2. > > What can be the issue here? Can anyone guide me? > > Regards, > Amarnath MB >
