void __init handle_uboot_args()

in kernel/setup.c [498:550]

• 36 lines of code
• 12 McCabe index (conditional complexity)

void __init handle_uboot_args(void)
{
	bool use_embedded_dtb = true;
	bool append_cmdline = false;

	/* check that we know this tag */
	if (uboot_tag != UBOOT_TAG_NONE &&
	    uboot_tag != UBOOT_TAG_CMDLINE &&
	    uboot_tag != UBOOT_TAG_DTB) {
		pr_warn(IGNORE_ARGS "invalid uboot tag: '%08x'\n", uboot_tag);
		goto ignore_uboot_args;
	}

	if (uboot_magic != UBOOT_MAGIC_VALUE) {
		pr_warn(IGNORE_ARGS "non zero uboot magic\n");
		goto ignore_uboot_args;
	}

	if (uboot_tag != UBOOT_TAG_NONE &&
            uboot_arg_invalid((unsigned long)uboot_arg)) {
		pr_warn(IGNORE_ARGS "invalid uboot arg: '%px'\n", uboot_arg);
		goto ignore_uboot_args;
	}

	/* see if U-boot passed an external Device Tree blob */
	if (uboot_tag == UBOOT_TAG_DTB) {
		machine_desc = setup_machine_fdt((void *)uboot_arg);

		/* external Device Tree blob is invalid - use embedded one */
		use_embedded_dtb = !machine_desc;
	}

	if (uboot_tag == UBOOT_TAG_CMDLINE)
		append_cmdline = true;

ignore_uboot_args:

	if (use_embedded_dtb) {
		machine_desc = setup_machine_fdt(__dtb_start);
		if (!machine_desc)
			panic("Embedded DT invalid\n");
	}

	/*
	 * NOTE: @boot_command_line is populated by setup_machine_fdt() so this
	 * append processing can only happen after.
	 */
	if (append_cmdline) {
		/* Ensure a whitespace between the 2 cmdlines */
		strlcat(boot_command_line, " ", COMMAND_LINE_SIZE);
		strlcat(boot_command_line, uboot_arg, COMMAND_LINE_SIZE);
	}
}