bootstd: Provide a bootmeth method to obtain state info

Some bootmeths can provide information about what is available to boot.
For example, VBE simple provides access to the firmware state.

Add a new method for this, along with a sandbox test.

Signed-off-by: Simon Glass <[email protected]>

1 files changed, 37 insertions, 1 deletions

diff --git a/include/bootmeth.h b/include/bootmeth.h
index 484e503e338..4967031a0a8 100644
--- a/include/bootmeth.h
+++ b/include/bootmeth.h
@@ -24,7 +24,25 @@ struct bootmeth_uc_plat {
 /** struct bootmeth_ops - Operations for boot methods */
 struct bootmeth_ops {
 	/**
-	 * check_supported() - check if a bootmeth supports this bootflow
+	 * get_state_desc() - get detailed state information
+	 *
+	 * Prodecues a textual description of the state of the bootmeth. This
+	 * can include newline characters if it extends to multiple lines. It
+	 * must be a nul-terminated string.
+	 *
+	 * This may involve reading state from the system, e.g. some data in
+	 * the firmware area.
+	 *
+	 * @dev:	Bootmethod device to check
+	 * @buf:	Buffer to place the info in (terminator must fit)
+	 * @maxsize:	Size of buffer
+	 * Returns: 0 if OK, -ENOSPC is buffer is too small, other -ve error if
+	 * something else went wrong
+	 */
+	int (*get_state_desc)(struct udevice *dev, char *buf, int maxsize);
+
+	/**
+	 * check_supported() - check if a bootmeth supports this bootdev
 	 *
 	 * This is optional. If not provided, the bootdev is assumed to be
 	 * supported
@@ -92,6 +110,24 @@ struct bootmeth_ops {
 #define bootmeth_get_ops(dev)  ((struct bootmeth_ops *)(dev)->driver->ops)
 
 /**
+ * bootmeth_get_state_desc() - get detailed state information
+ *
+ * Prodecues a textual description of the state of the bootmeth. This
+ * can include newline characters if it extends to multiple lines. It
+ * must be a nul-terminated string.
+ *
+ * This may involve reading state from the system, e.g. some data in
+ * the firmware area.
+ *
+ * @dev:	Bootmethod device to check
+ * @buf:	Buffer to place the info in (terminator must fit)
+ * @maxsize:	Size of buffer
+ * Returns: 0 if OK, -ENOSPC is buffer is too small, other -ve error if
+ * something else went wrong
+ */
+int bootmeth_get_state_desc(struct udevice *dev, char *buf, int maxsize);
+
+/**
  * bootmeth_check() - check if a bootmeth supports this bootflow
  *
  * This is optional. If not provided, the bootdev is assumed to be