Hi Steve,
Thank you for your help. By adding the lines in the clock.c, the system can now catch the mmc1. After entering the command "mmc dev 1", the console shows it is the current device. However, if we want to read the mmc1, failure happens. We tried to read mmc0 and mmc1 in the following ways.
U-Boot# mmc dev 0
mmc0 is current device
U-Boot# mmc read 0x90000000 0x100 0x10
MMC read: dev # 0, block # 256, count 16 ...16 blocks read: OK
U-Boot# mmc dev 1
mmc_send_cmd : timeout: No status update
Card did not respond to voltage select!
mmc1(part 0) is current device
U-Boot# mmc read 0x90000000 0x100 0x10
MMC read: dev # 1, block # 256, count 16 ... mmc_send_cmd : timeout: No status update
Card did not respond to voltage select!
MMC: block number 0x110 exceeds max(0x0)
0 blocks read: ERROR
We added some debug information and found out that the mmc_stat in mmc_send_cmd (/drivers/mmc/omap_hsmmc.c) becomes 0x18000. It means that in the mmc1 register, SD_STAT becomes 0x00018000, indicating the timeout error and error interrupt. Do you have any ideas how to debug these errors. I really appreciate any advice from you guys. Thank you!
Sincerely,
Jun Sheng