Add in-system barebox update infrastructure

Currently in-system update means to write an arbitrary file to
an arbitrary device. There is no sanity check if the flashed image
is of the right type or will fit onto the device. Furthermore some
SoCs need a special preparation step for their images before
flashing them.

This adds a barebox in-system update infrastructure. Boards can
register update handlers which know how to make the board bootable.
The available handlers can be listed to be able to select one,
different force levels give the user the chance to know it better.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

1 files changed, 150 insertions, 0 deletions

diff --git a/common/bbu.c b/common/bbu.c
new file mode 100644
index 0000000000..92f8d2b2f4
--- /dev/null
+++ b/common/bbu.c
@@ -0,0 +1,150 @@
+/*
+ * bbu.c - barebox update functions
+ *
+ * Copyright (c) 2012 Sascha Hauer <s.hauer@pengutronix.de>, Pengutronix
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+#include <common.h>
+#include <bbu.h>
+#include <linux/list.h>
+#include <errno.h>
+#include <readkey.h>
+
+static LIST_HEAD(bbu_image_handlers);
+
+int bbu_force(struct bbu_data *data, const char *fmt, ...)
+{
+	va_list args;
+
+	printf("UPDATE: ");
+
+	va_start(args, fmt);
+
+	vprintf(fmt, args);
+
+	va_end(args);
+
+	if (!(data->flags & BBU_FLAG_FORCE))
+		goto out;
+
+	if (!data->force)
+		goto out;
+
+	data->force--;
+
+	printf(" (forced)\n");
+
+	return 1;
+out:
+	printf("\n");
+
+	return 0;
+}
+
+int bbu_confirm(struct bbu_data *data)
+{
+	int key;
+
+	if (data->flags & BBU_FLAG_YES)
+		return 0;
+
+	printf("update barebox from %s using handler %s to %s (y/n)?\n",
+			data->imagefile, data->handler_name,
+			data->devicefile);
+
+	key = read_key();
+
+	if (key == 'y')
+		return 0;
+
+	return -EINTR;
+}
+
+static struct bbu_handler *bbu_find_handler(const char *name, unsigned long flags)
+{
+	struct bbu_handler *handler;
+
+	list_for_each_entry(handler, &bbu_image_handlers, list) {
+		if (!name) {
+			if (flags & BBU_HANDLER_FLAG_DEFAULT)
+				return handler;
+			continue;
+		}
+
+		if (!strcmp(handler->name, name))
+			return handler;
+	}
+
+	return NULL;
+}
+
+/*
+ * do a barebox update with data from *data
+ */
+int barebox_update(struct bbu_data *data)
+{
+	struct bbu_handler *handler;
+	int ret;
+
+	handler = bbu_find_handler(data->handler_name, data->flags);
+	if (!handler)
+		return -ENODEV;
+
+	if (!data->devicefile)
+		data->devicefile = handler->devicefile;
+
+	ret = handler->handler(handler, data);
+	if (ret == -EINTR)
+		printf("update aborted\n");
+
+	if (!ret)
+		printf("update succeeded\n");
+
+	return ret;
+}
+
+/*
+ * print a list of all registered update handlers
+ */
+void bbu_handlers_list(void)
+{
+	struct bbu_handler *handler;
+
+	if (list_empty(&bbu_image_handlers))
+		printf("(none)\n");
+
+	list_for_each_entry(handler, &bbu_image_handlers, list)
+		printf("%s%-11s -> %-10s\n",
+				handler->flags & BBU_HANDLER_FLAG_DEFAULT ?
+				"* " : "  ",
+				handler->name,
+				handler->devicefile);
+}
+
+/*
+ * register a new update handler
+ */
+int bbu_register_handler(struct bbu_handler *handler)
+{
+	if (bbu_find_handler(handler->name, 0))
+		return -EBUSY;
+
+	if (handler->flags & BBU_HANDLER_FLAG_DEFAULT &&
+			bbu_find_handler(NULL, BBU_HANDLER_FLAG_DEFAULT))
+		return -EBUSY;
+
+	list_add_tail(&handler->list, &bbu_image_handlers);
+
+	return 0;
+}