bsps/shared/flash: Add a JFFS2 flashdev driver

This adds generic JFFS2 interworking code that allows JFFS2 to be used
on top of any flashdev backend. It currently only supports NOR flashdev
backends.

bsps/include/dev/flash/jffs2_flashdev.h

@@ -0,0 +1,56 @@
+/* SPDX-License-Identifier: BSD-2-Clause */
+
+/*
+ * Copyright (C) 2024 On-Line Applications Research Corporation (OAR)
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef JFFS2_FLASHDEV_H
+#define JFFS2_FLASHDEV_H
+
+#include <dev/flash/flashdev.h>
+#include <rtems/jffs2.h>
+#include <rtems/rtems/status.h>
+
+/**
+ * This function mounts a JFFS2 partition over the specified region on a
+ * flashdev-controlled device file.
+ *
+ * @param  flashdev_path is a device file created by the flashdev backend
+ * @param  mount_dir is the location at which to mount the JFFS2 filesystem
+ * @param  region is a description of the segment of the device file to mount
+ * @param  compressor_control is the JFFS2 compression control
+ * @param  read_only is a flag indicating whether the mounted JFFS2 filesystem
+ *         can be written
+ *
+ * @return RTEMS_SUCCESSFUL on success.
+ */
+rtems_status_code jffs2_flashdev_mount(
+  const char *flashdev_path,
+  const char *mount_dir,
+  rtems_flashdev_region *region,
+  rtems_jffs2_compressor_control *compressor_control,
+  bool read_only
+);
+
+#endif /* JFFS2_FLASHDEV_H */