Linux/AM4378: Does the AM437X support the emmc chip with working on x4 I/O4s?

Hi Jianhua,

Yes, AM437x MMC/SD controller support eMMC in 4-bit mode. AM437x EVM board comes with eMMC in 8-bit mode, but ROM Code is using only 4-bit data bus, check below AM437x TRM sections:

5.2.6.5 MMC/SD Cards
5.2.6.5.8 Pins Used
17.1.1 MMCSD Features

But note that linux kernel MMC driver support only 8-bit mode for eMMC:

software-dl.ti.com/.../Foundational_Components_Kernel_Drivers.html


Regards,
Pavel