Hello Logi Francis,
"Card did not respond to voltage select" is caused by failure of the ACMD41, which means that the voltage selection settings by the host does not match with eMMC device.
Please check RCW configuration.
SDHC_BASE (371): 0;
SPI_BASE (382-383): 01 to use 8-bit eMMC support;
Please refer to the attached schematics on T2080QDS.
Please try increase your timeout value SYSCTL[DTOCV] to be E.
Thanks,
Yiping