Dear Lei Wen, In message <aanlktikdun37v6tvypy0hyjrb9oj4xk-lynpsida7...@mail.gmail.com> you wrote: > > EMMC is sightly different witht the other device with partition.
Maybe. But does this really require a different iunterface in the U-Boot context? I doubt that. > For IDE as example, we could copy file between part A and B without problem. No, we cannot. U-Boot can only read _or_ write form mass storage operations, so a copy operation would always require a "read from device to RAM buffer", "write to device from RAM buffer" sequence. The same can obviously be done with EMMC as well. > But for EMMC, the boot partition is different with the normal partition. > We need to send a special command to do the switch, not with the > different offset. Thisis an internal implementation detail. As a user, I do not want to know about it. I just want to read or write data to some partition. The rest is driver internals. > If we need to copy file between those two partition, we need to send > switch command > before copy operation. So where is the problem? See above. We always have TWO separate operations, and each of them will select a device/partition. > It is a hardware one. IDE or usb masstorage has no such ability... I see no difference from the user point of view. The internal implementation may be different, but that doesn't matter. > For mmc may change the hardware partition, but fat command cannot... > It is because > it need to be compatiable with other devices that have no hardware > partition... I don;t understand what you want to tell me here. My complaint is that your new code is _not_ compatible with other divices, and I see no reason for such an incompatibility. Best regards, Wolfgang Denk -- DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: w...@denx.de Computers are not intelligent. They only think they are. _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
