X-Git-Url: https://git.karo-electronics.de/?a=blobdiff_plain;f=doc%2FREADME.commands;h=afd5577b0a9ce66b86c52f7cae595eb7d914e556;hb=88a0739d9d909f72fce1037ed0be95f4b62fe448;hp=27815d2ba18faada4344e68ed65ac3b188569797;hpb=dbe20fc79736d4f99a9bfaafeae600c9348504df;p=karo-tx-uboot.git diff --git a/doc/README.commands b/doc/README.commands index 27815d2ba1..afd5577b0a 100644 --- a/doc/README.commands +++ b/doc/README.commands @@ -15,17 +15,22 @@ help: Long description. This is a string **** Behind the scene ****** -The structure created is named with a special prefix (__u_boot_cmd_) -and placed by the linker in a special section. +The structure created is named with a special prefix and placed by +the linker in a special section using the linker lists mechanism +(see include/linker_lists.h) This makes it possible for the final link to extract all commands compiled into any object code and construct a static array so the -command can be found in an array starting at __u_boot_cmd_start. +command array can be iterated over using the linker lists macros. + +The linker lists feature ensures that the linker does not discard +these symbols when linking full U-Boot even though they are not +referenced in the source code as such. If a new board is defined do not forget to define the command section -by writing in u-boot.lds ($(TOPDIR)/board/boardname/u-boot.lds) these +by writing in u-boot.lds ($(srctree)/board/boardname/u-boot.lds) these 3 lines: - __u_boot_cmd_start = .; - .u_boot_cmd : { *(.u_boot_cmd) } - __u_boot_cmd_end = .; + .u_boot_list : { + KEEP(*(SORT(.u_boot_list*))); + }