mmc init fails after soft reset on T1042
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
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
On 1/26/20 12:42 AM, 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.
Does mmcinfo display correct information? Or Does it boot with 1bit mode?
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.
It seems that you have set to wrong value for your eMMC. Could you share more information?
Best Regards, Jaehoon Chung
What can be the issue here? Can anyone guide me?
Regards, Amarnath MB
participants (3)
-
Amarnath MB -
Jaehoon Chung -
Mauro Condarelli