[PATCH v2 01/10] commands: devlookup: honour global.bootm.root_param for -k

[Ahmad Fatoum <a.fatoum@pengutronix.de>]

From: Ahmad Fatoum <a.fatoum@barebox.org>

devlookup -k prints the root= option that bootm would add for
global.bootm.root_dev, but it always calls it root=, even though
global.bootm.root_param now allows bootm to use e.g. verity= instead, so
only the initramfs and not the kernel picks up the root file system.

Let's use the same option name as bootm, so scripts can assemble the
option bootm would append for images it doesn't append it to, like
unified kernel images.

Assisted-by: Claude:opus-5.5
Signed-off-by: Ahmad Fatoum <a.fatoum@barebox.org>
---
 commands/devlookup.c | 5 +++--
 common/block.c       | 5 +++--
 include/block.h      | 6 ++++--
 3 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/commands/devlookup.c b/commands/devlookup.c
index 8f3468735267..164c005236de 100644
--- a/commands/devlookup.c
+++ b/commands/devlookup.c
@@ -85,7 +85,8 @@ static int do_devlookup(int argc, char *argv[])
 	}
 
 	if (kernelopt)
-		val = buf = cdev_get_linux_rootarg(cdev);
+		val = buf = cdev_get_linux_rootarg(cdev,
+			getenv_nonempty("global.bootm.root_param") ?: "root");
 	else if (paramname)
 		val = dev_get_param(cdev->dev, paramname);
 	else
@@ -109,7 +110,7 @@ BAREBOX_CMD_HELP_TEXT("parameter with that name is looked up.")
 BAREBOX_CMD_HELP_TEXT("")
 BAREBOX_CMD_HELP_TEXT("Options:")
 BAREBOX_CMD_HELP_OPT ("-v",  "write output to VARIABLE instead of printing it")
-BAREBOX_CMD_HELP_OPT ("-k",  "output kernel rootarg line")
+BAREBOX_CMD_HELP_OPT ("-k",  "output kernel rootarg line (see global.bootm.root_param)")
 BAREBOX_CMD_HELP_OPT ("-a",  "output resolution of cdev alias")
 BAREBOX_CMD_HELP_END
 
diff --git a/common/block.c b/common/block.c
index 5441c7ca1848..16075bb146ec 100644
--- a/common/block.c
+++ b/common/block.c
@@ -665,7 +665,8 @@ int cdev_get_linux_root_and_opts(const struct cdev *partcdev, const char **root,
 	return 0;
 }
 
-char *cdev_get_linux_rootarg(const struct cdev *partcdev)
+char *cdev_get_linux_rootarg(const struct cdev *partcdev,
+			     const char *root_param)
 {
 	int err;
 	const char *root = NULL;
@@ -675,5 +676,5 @@ char *cdev_get_linux_rootarg(const struct cdev *partcdev)
 	if (err)
 		return NULL;
 
-	return format_root_bootarg("root", root, rootopts);
+	return format_root_bootarg(root_param, root, rootopts);
 }
diff --git a/include/block.h b/include/block.h
index 065ae81358b4..91ab91f9109b 100644
--- a/include/block.h
+++ b/include/block.h
@@ -109,7 +109,8 @@ static inline int block_flush(struct block_device *blk)
 
 #ifdef CONFIG_BLOCK
 unsigned file_list_add_blockdevs(struct file_list *files);
-char *cdev_get_linux_rootarg(const struct cdev *partcdev);
+char *cdev_get_linux_rootarg(const struct cdev *partcdev,
+			     const char *root_param);
 int cdev_get_linux_root_and_opts(const struct cdev *partcdev, const char **root,
 				 const char **rootopts);
 #else
@@ -117,7 +118,8 @@ static inline unsigned file_list_add_blockdevs(struct file_list *files)
 {
 	return 0;
 }
-static inline char *cdev_get_linux_rootarg(const struct cdev *partcdev)
+static inline char *cdev_get_linux_rootarg(const struct cdev *partcdev,
+					   const char *root_param)
 {
 	return NULL;
 }
-- 
2.47.3