[U-Boot] in cmd_df.c, why does U_BOOT_CMD reference cmd not defined in that file?

always willing to embarrass myself with silly questions, what is going on in cmd_df.c? note the command defined is apparently "sf", which invokes something called "do_serial_flash", which is nowhere to be seen here:

/* * Command for accessing DataFlash. * * Copyright (C) 2008 Atmel Corporation */ #include <common.h> #include <df.h>

static int do_df(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) { const char *cmd;

/* need at least two arguments */ if (argc < 2) goto usage;

cmd = argv[1];

if (strcmp(cmd, "init") == 0) { df_init(0, 0, 1000000); return 0; }

if (strcmp(cmd, "info") == 0) { df_show_info(); return 0; }

usage: return CMD_RET_USAGE; }

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")

i'm confused ...

rday