RPI U-boot Custom command

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Prepare application

There are many commands in u-boot-pi-rpi/common/cmd_*.c, choose one that is similar to your requirements and copy it. In the sample below I use "cmd_ja.c"

• Add the new source file to u-boot-pi-rpi/common directory

 /*
  * JA: my stuff
  */
 #include <common.h>
 #include <command.h>
 DECLARE_GLOBAL_DATA_PTR;
 
 static int do_ja(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
   {
   int rcode = 0;
   puts("in ja\n");
   for (;;)
     {
     puts("\n--------------\n");
     puts(" q    quit\n");
     puts(" a    run 'a'\n");
     puts(" b    run 'b'\n");
     puts(" c    run 'c'\n");
     puts("-- enter cmd: ");
     char c = getc();
     switch (c)
       {
       case 'q':
         puts("bye\n");
         return 0;
       case 'a':
         printf("doing 'a'!\n");
         break;
       case 'b':
         printf("doing 'b'!\n");
         break;
       case 'c':
         printf("doing 'c'!\n");
         break;
       case '\r':
         break;
       default:
         printf("huh? don't know: '%c'\n", c);
         break;
       }
     }
 
   printf("exiting. rcode=%d\n\n", rcode);
   return rcode;
   }
 
 /***************************************************/
 //        name,#parms, isrepeatable?, cmd list, help text
 U_BOOT_CMD(ja, 1, 1, do_ja, "do cool things", "invoke the 'ja' application");

• Edit Common Makefile:

 edit u-boot-pi-rpi/common/Makefile
 add the executable to the COBS-y variable
 
 45,47d44
 < #JA: add my own command
 < COBJS-y += cmd_ja.o

• re-compile

 ./doit

• the command is now in the u-boot executable, so load the sdcard as normal

 ./deployit

run it

 U-Boot> ja
 in ja
 
 --------------
  q    quit
  a    run 'a'
  b    run 'b'
  c    run 'c'
  -- enter cmd: doing 'a'!
 
 --------------
  q    quit
  a    run 'a'
  b    run 'b'
  c    run 'c'
 -- enter cmd: huh? don't know: 'n'

 --------------
  q    quit
  a    run 'a'
  b    run 'b'
  c    run 'c'
 -- enter cmd: bye
 U-Boot> 

Try help:

 U-Boot> help
 <snip>
 itest   - return true/false on integer compare
 ja      - do cool thing
 load    - load binary file from a filesystem
 <snip>
 U-Boot> help ja
 ja - do cool thing
 
 Usage:
 ja invoke the 'ja' application
 U-Boot>