bootstd: Add the bootstd uclass and core implementation

The 'bootstd' device provides the central information about U-Boot
standard boot.

Add a uclass for bootstd and the various helpers needed to make it
work. Also add a binding file.

Signed-off-by: Simon Glass <sjg@chromium.org>

1 files changed, 80 insertions, 0 deletions

diff --git a/include/bootstd.h b/include/bootstd.h
new file mode 100644
index 0000000000..b002365f4f
--- /dev/null
+++ b/include/bootstd.h
@@ -0,0 +1,80 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Standard U-Boot boot framework
+ *
+ * Copyright 2021 Google LLC
+ * Written by Simon Glass <sjg@chromium.org>
+ */
+
+#ifndef __bootstd_h
+#define __bootstd_h
+
+struct udevice;
+
+/**
+ * struct bootstd_priv - priv data for the bootstd driver
+ *
+ * This is attached to the (only) bootstd device, so there is only one instance
+ * of this struct. It provides overall information about bootdevs and bootflows.
+ *
+ * @prefixes: NULL-terminated list of prefixes to use for bootflow filenames,
+ *	e.g. "/", "/boot/"; NULL if none
+ * @bootdev_order: Order to use for bootdevs (or NULL if none), with each item
+ *	being a bootdev label, e.g. "mmc2", "mmc1";
+ * @cur_bootdev: Currently selected bootdev (for commands)
+ * @cur_bootflow: Currently selected bootflow (for commands)
+ * @glob_head: Head for the global list of all bootflows across all bootdevs
+ * @bootmeth_count: Number of bootmeth devices in @bootmeth_order
+ * @bootmeth_order: List of bootmeth devices to use, in order, NULL-terminated
+ */
+struct bootstd_priv {
+	const char **prefixes;
+	const char **bootdev_order;
+	struct udevice *cur_bootdev;
+	struct bootflow *cur_bootflow;
+	struct list_head glob_head;
+	int bootmeth_count;
+	struct udevice **bootmeth_order;
+};
+
+/**
+ * bootstd_get_bootdev_order() - Get the boot-order list
+ *
+ * This reads the boot order, e.g. {"mmc0", "mmc2", NULL}
+ *
+ * The list is alloced by the bootstd driver so should not be freed. That is the
+ * reason for all the const stuff in the function signature
+ *
+ * Return: list of string points, terminated by NULL; or NULL if no boot order
+ */
+const char *const *const bootstd_get_bootdev_order(struct udevice *dev);
+
+/**
+ * bootstd_get_prefixes() - Get the filename-prefixes list
+ *
+ * This reads the prefixes, e.g. {"/", "/bpot", NULL}
+ *
+ * The list is alloced by the bootstd driver so should not be freed. That is the
+ * reason for all the const stuff in the function signature
+ *
+ * Return: list of string points, terminated by NULL; or NULL if no boot order
+ */
+const char *const *const bootstd_get_prefixes(struct udevice *dev);
+
+/**
+ * bootstd_get_priv() - Get the (single) state for the bootstd system
+ *
+ * The state holds a global list of all bootflows that have been found.
+ *
+ * Return: 0 if OK, -ve if the uclass does not exist
+ */
+int bootstd_get_priv(struct bootstd_priv **stdp);
+
+/**
+ * bootstd_clear_glob() - Clear the global list of bootflows
+ *
+ * This removes all bootflows globally and across all bootdevs.
+ */
+void bootstd_clear_glob(void);
+
+#endif