When using boot scripts it can become quite hard to understand which commands are actually executed during bootup (e.g. where is a kernel image loaded from or which DTB is in use).

Shell scripts suffer from a similar problem and many shells address this problem with a command execution tracer (e.g. BASH has xtrace, which can be enabled by "set -x").

This patch introduces a command tracer for U-Boot, which prints every command with its arguments before it is executed.

Signed-off-by: Christoph Muellner christoph.muellner@theobroma-systems.com

---

cmd/Kconfig | 11 +++++++++++ common/command.c | 14 ++++++++++++++ 2 files changed, 25 insertions(+)

diff --git a/cmd/Kconfig b/cmd/Kconfig index 0b07b3b9d77..eeadc3827cb 100644 --- a/cmd/Kconfig +++ b/cmd/Kconfig @@ -53,6 +53,17 @@ config SYS_PROMPT This string is displayed in the command line to the left of the cursor.

+config SYS_XTRACE + string "Command execution tracer" + depends on CMDLINE + default y if CMDLINE + help + This option enables the possiblity to print all commands before + executing them and after all variables are evaluated (similar + to Bash's xtrace/'set -x' feature). + To enable the tracer a variable "xtrace" needs to be defined in + the environment. + menu "Autoboot options"

config AUTOBOOT diff --git a/common/command.c b/common/command.c index e14d1fa1d6b..e192bb2a619 100644 --- a/common/command.c +++ b/common/command.c @@ -574,6 +574,20 @@ enum command_ret_t cmd_process(int flag, int argc, char * const argv[], enum command_ret_t rc = CMD_RET_SUCCESS; cmd_tbl_t *cmdtp;

+#if defined(CONFIG_SYS_XTRACE) + char *xtrace; + + xtrace = env_get("xtrace"); + if (xtrace) { + puts("+"); + for (int i = 0; i < argc; i++) { + puts(" "); + puts(argv[i]); + } + puts("\n"); + } +#endif + /* Look up command in command table */ cmdtp = find_cmd(argv[0]); if (cmdtp == NULL) {