diff options
Diffstat (limited to 'doc')
| -rw-r--r-- | doc/README.commands | 186 | ||||
| -rw-r--r-- | doc/develop/commands.rst | 226 | ||||
| -rw-r--r-- | doc/develop/index.rst | 1 |
3 files changed, 227 insertions, 186 deletions
diff --git a/doc/README.commands b/doc/README.commands deleted file mode 100644 index 22ab063fdc0..00000000000 --- a/doc/README.commands +++ /dev/null @@ -1,186 +0,0 @@ -Command definition ------------------- - -Commands are added to U-Boot by creating a new command structure. -This is done by first including command.h, then using the U_BOOT_CMD() or the -U_BOOT_CMD_COMPLETE macro to fill in a struct cmd_tbl struct. - -U_BOOT_CMD(name, maxargs, repeatable, command, "usage", "help") -U_BOOT_CMD_COMPLETE(name, maxargs, repeatable, command, "usage, "help", comp) - -name: The name of the command. THIS IS NOT a string. - -maxargs: The maximum number of arguments this function takes including - the command itself. - -repeatable: Either 0 or 1 to indicate if autorepeat is allowed. - -command: Pointer to the command function. This is the function that is - called when the command is issued. - -usage: Short description. This is a string. - -help: Long description. This is a string. The long description is - only available if CONFIG_SYS_LONGHELP is defined. - -comp: Pointer to the completion function. May be NULL. - This function is called if the user hits the TAB key while - entering the command arguments to complete the entry. Command - completion is only available if CONFIG_AUTO_COMPLETE is defined. - -Sub-command definition ----------------------- - -Likewise an array of struct cmd_tbl holding sub-commands can be created using either -of the following macros: - -* U_BOOT_CMD_MKENT(name, maxargs, repeatable, command, "usage", "help") -* U_BOOT_CMD_MKENTCOMPLETE(name, maxargs, repeatable, command, "usage, "help", - comp) - -This table has to be evaluated in the command function of the main command, e.g. - - static struct cmd_tbl cmd_sub[] = { - U_BOOT_CMD_MKENT(foo, CONFIG_SYS_MAXARGS, 1, do_foo, "", ""), - U_BOOT_CMD_MKENT(bar, CONFIG_SYS_MAXARGS, 1, do_bar, "", ""), - }; - - static int do_cmd(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[]) - { - struct cmd_tbl *cp; - - if (argc < 2) - return CMD_RET_USAGE; - - /* drop sub-command argument */ - argc--; - argv++; - - cp = find_cmd_tbl(argv[0], cmd_ut_sub, ARRAY_SIZE(cmd_sub)); - - if (cp) - return cp->cmd(cmdtp, flag, argc, argv); - - return CMD_RET_USAGE; - } - -Command function ----------------- - -The command function pointer has to be of type -int (*cmd)(struct cmd_tbl *cmdtp, int flag, int argc, const char *argv[]); - -cmdtp: Table entry describing the command (see above). - -flag: A bitmap which may contain the following bit: - CMD_FLAG_REPEAT - The last command is repeated. - CMD_FLAG_BOOTD - The command is called by the bootd command. - CMD_FLAG_ENV - The command is called by the run command. - -argc: Number of arguments including the command. - -argv: Arguments. - -Allowable return value are: - -CMD_RET_SUCCESS The command was successfully executed. - -CMD_RET_FAILURE The command failed. - -CMD_RET_USAGE The command was called with invalid parameters. This value - leads to the display of the usage string. - -Completion function -------------------- - -The completion function pointer has to be of type -int (*complete)(int argc, char *const argv[], char last_char, - int maxv, char *cmdv[]); - -argc: Number of arguments including the command. - -argv: Arguments. - -last_char: The last character in the command line buffer. - -maxv: Maximum number of possible completions that may be returned by - the function. - -cmdv: Used to return possible values for the last argument. The last - possible completion must be followed by NULL. - -The function returns the number of possible completions (without the terminating -NULL value). - -Behind the scene ----------------- - -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 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 ($(srctree)/board/boardname/u-boot.lds) these -3 lines: - - .u_boot_list : { - KEEP(*(SORT(.u_boot_list*))); - } - -Writing tests -------------- - -All new commands should have tests. Tests for existing commands are very -welcome. - -It is fairly easy to write a test for a command. Enable it in sandbox, and -then add code that runs the command and checks the output. - -Here is an example: - -/* Test 'acpi items' command */ -static int dm_test_acpi_cmd_items(struct unit_test_state *uts) -{ - struct acpi_ctx ctx; - void *buf; - - buf = malloc(BUF_SIZE); - ut_assertnonnull(buf); - - ctx.current = buf; - ut_assertok(acpi_fill_ssdt(&ctx)); - console_record_reset(); - run_command("acpi items", 0); - ut_assert_nextline("dev 'acpi-test', type 1, size 2"); - ut_assert_nextline("dev 'acpi-test2', type 1, size 2"); - ut_assert_console_end(); - - ctx.current = buf; - ut_assertok(acpi_inject_dsdt(&ctx)); - console_record_reset(); - run_command("acpi items", 0); - ut_assert_nextline("dev 'acpi-test', type 2, size 2"); - ut_assert_nextline("dev 'acpi-test2', type 2, size 2"); - ut_assert_console_end(); - - console_record_reset(); - run_command("acpi items -d", 0); - ut_assert_nextline("dev 'acpi-test', type 2, size 2"); - ut_assert_nextlines_are_dump(2); - ut_assert_nextline("%s", ""); - ut_assert_nextline("dev 'acpi-test2', type 2, size 2"); - ut_assert_nextlines_are_dump(2); - ut_assert_nextline("%s", ""); - ut_assert_console_end(); - - return 0; -} -DM_TEST(dm_test_acpi_cmd_items, UT_TESTF_SCAN_PDATA | UT_TESTF_SCAN_FDT); diff --git a/doc/develop/commands.rst b/doc/develop/commands.rst new file mode 100644 index 00000000000..c72d1b0aaad --- /dev/null +++ b/doc/develop/commands.rst @@ -0,0 +1,226 @@ +.. SPDX-License-Identifier: GPL-2.0+ + +Implementing shell commands +=========================== + +Command definition +------------------ + +Commands are added to U-Boot by creating a new command structure. +This is done by first including command.h, then using the U_BOOT_CMD() or the +U_BOOT_CMD_COMPLETE macro to fill in a struct cmd_tbl structure. + +.. code-block:: c + + U_BOOT_CMD(name, maxargs, repeatable, command, "usage", "help") + U_BOOT_CMD_COMPLETE(name, maxargs, repeatable, command, "usage, "help", comp) + +name + The name of the command. This is **not** a string. + +maxargs + The maximum number of arguments this function takes including + the command itself. + +repeatable + Either 0 or 1 to indicate if autorepeat is allowed. + +command + Pointer to the command function. This is the function that is + called when the command is issued. + +usage + Short description. This is a string. + +help + Long description. This is a string. The long description is + only available if CONFIG_SYS_LONGHELP is defined. + +comp + Pointer to the completion function. May be NULL. + This function is called if the user hits the TAB key while + entering the command arguments to complete the entry. Command + completion is only available if CONFIG_AUTO_COMPLETE is defined. + +Sub-command definition +---------------------- + +Likewise an array of struct cmd_tbl holding sub-commands can be created using +either of the following macros: + +.. code-block:: c + + U_BOOT_CMD_MKENT(name, maxargs, repeatable, command, "usage", "help") + U_BOOT_CMD_MKENTCOMPLETE(name, maxargs, repeatable, command, "usage, "help", comp) + +This table has to be evaluated in the command function of the main command, e.g. + +.. code-block:: c + + static struct cmd_tbl cmd_sub[] = { + U_BOOT_CMD_MKENT(foo, CONFIG_SYS_MAXARGS, 1, do_foo, "", ""), + U_BOOT_CMD_MKENT(bar, CONFIG_SYS_MAXARGS, 1, do_bar, "", ""), + }; + + static int do_cmd(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[]) + { + struct cmd_tbl *cp; + + if (argc < 2) + return CMD_RET_USAGE; + + /* drop sub-command argument */ + argc--; + argv++; + + cp = find_cmd_tbl(argv[0], cmd_ut_sub, ARRAY_SIZE(cmd_sub)); + + if (cp) + return cp->cmd(cmdtp, flag, argc, argv); + + return CMD_RET_USAGE; + } + +Command function +---------------- + +The command function pointer has to be of type + +.. code-block:: c + + int (*cmd)(struct cmd_tbl *cmdtp, int flag, int argc, const char *argv[]); + +cmdtp + Table entry describing the command (see above). + +flag + A bitmap which may contain the following bits + + * CMD_FLAG_REPEAT - The last command is repeated. + * CMD_FLAG_BOOTD - The command is called by the bootd command. + * CMD_FLAG_ENV - The command is called by the run command. + +argc + Number of arguments including the command. + +argv + Arguments. + +Allowable return value are: + +CMD_RET_SUCCESS + The command was successfully executed. + +CMD_RET_FAILURE + The command failed. + +CMD_RET_USAGE + The command was called with invalid parameters. This value + leads to the display of the usage string. + +Completion function +------------------- + +The completion function pointer has to be of type + +.. code-block:: c + + int (*complete)(int argc, char *const argv[], char last_char, + int maxv, char *cmdv[]); + +argc + Number of arguments including the command. + +argv + Arguments. + +last_char + The last character in the command line buffer. + +maxv + Maximum number of possible completions that may be returned by + the function. + +cmdv + Used to return possible values for the last argument. The last + possible completion must be followed by NULL. + +The function returns the number of possible completions (without the terminating +NULL value). + +Behind the scene +---------------- + +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 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 ($(srctree)/board/boardname/u-boot.lds) these +3 lines: + +.. code-block:: c + + .u_boot_list : { + KEEP(*(SORT(.u_boot_list*))); + } + +Writing tests +------------- + +All new commands should have tests. Tests for existing commands are very +welcome. + +It is fairly easy to write a test for a command. Enable it in sandbox, and +then add code that runs the command and checks the output. + +Here is an example: + +.. code-block:: c + + /* Test 'acpi items' command */ + static int dm_test_acpi_cmd_items(struct unit_test_state *uts) + { + struct acpi_ctx ctx; + void *buf; + + buf = malloc(BUF_SIZE); + ut_assertnonnull(buf); + + ctx.current = buf; + ut_assertok(acpi_fill_ssdt(&ctx)); + console_record_reset(); + run_command("acpi items", 0); + ut_assert_nextline("dev 'acpi-test', type 1, size 2"); + ut_assert_nextline("dev 'acpi-test2', type 1, size 2"); + ut_assert_console_end(); + + ctx.current = buf; + ut_assertok(acpi_inject_dsdt(&ctx)); + console_record_reset(); + run_command("acpi items", 0); + ut_assert_nextline("dev 'acpi-test', type 2, size 2"); + ut_assert_nextline("dev 'acpi-test2', type 2, size 2"); + ut_assert_console_end(); + + console_record_reset(); + run_command("acpi items -d", 0); + ut_assert_nextline("dev 'acpi-test', type 2, size 2"); + ut_assert_nextlines_are_dump(2); + ut_assert_nextline("%s", ""); + ut_assert_nextline("dev 'acpi-test2', type 2, size 2"); + ut_assert_nextlines_are_dump(2); + ut_assert_nextline("%s", ""); + ut_assert_console_end(); + + return 0; + } + DM_TEST(dm_test_acpi_cmd_items, UT_TESTF_SCAN_PDATA | UT_TESTF_SCAN_FDT); diff --git a/doc/develop/index.rst b/doc/develop/index.rst index 89e80eab945..c95a8d6b123 100644 --- a/doc/develop/index.rst +++ b/doc/develop/index.rst @@ -8,6 +8,7 @@ Develop U-Boot :maxdepth: 2 coccinelle + commands crash_dumps global_data logging |