[U-Boot] the weirdness with cmd_df.c

i mentioned this this weekend as well, can someone clarify this? the source file cmd_df.c looks weird:

U_BOOT_CMD( sf, 2, 1, do_serial_flash, "Serial flash sub-system", "probe [bus:]cs - init flash device on given SPI bus and CS")

so the source file "cmd_df.c" allegedly defines a command called "sf", which invokes "do_serial_flash", which isn't even defined in that source file -- what's defined in that file is "do_df". i don't see "do_serial_flash" defined anywhere in the u-boot source tree. am i just being blind? i see no reference to that source file in Makefile, so i'm guessing it's historical cruft that could be deleted?

rday