linux/drivers/mtd/maps/pmcmsp-ramroot.c

106 lines
2.9 KiB
C

/*
* Mapping of the rootfs in a physical region of memory
*
* Copyright (C) 2005-2007 PMC-Sierra Inc.
* Author: Andrew Hughes, Andrew_Hughes@pmc-sierra.com
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*
* THIS SOFTWARE IS PROVIDED ``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 AUTHOR 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.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/fs.h>
#include <linux/root_dev.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/map.h>
#include <asm/io.h>
#include <msp_prom.h>
static struct mtd_info *rr_mtd;
struct map_info rr_map = {
.name = "ramroot",
.bankwidth = 4,
};
static int __init init_rrmap(void)
{
void *ramroot_start;
unsigned long ramroot_size;
/* Check for supported rootfs types */
if (get_ramroot(&ramroot_start, &ramroot_size)) {
rr_map.phys = CPHYSADDR(ramroot_start);
rr_map.size = ramroot_size;
printk(KERN_NOTICE
"PMC embedded root device: 0x%08lx @ 0x%08lx\n",
rr_map.size, (unsigned long)rr_map.phys);
} else {
printk(KERN_ERR
"init_rrmap: no supported embedded rootfs detected!\n");
return -ENXIO;
}
/* Map rootfs to I/O space for block device driver */
rr_map.virt = ioremap(rr_map.phys, rr_map.size);
if (!rr_map.virt) {
printk(KERN_ERR "Failed to ioremap\n");
return -EIO;
}
simple_map_init(&rr_map);
rr_mtd = do_map_probe("map_ram", &rr_map);
if (rr_mtd) {
rr_mtd->owner = THIS_MODULE;
add_mtd_device(rr_mtd);
ROOT_DEV = MKDEV(MTD_BLOCK_MAJOR, rr_mtd->index);
return 0;
}
iounmap(rr_map.virt);
return -ENXIO;
}
static void __exit cleanup_rrmap(void)
{
del_mtd_device(rr_mtd);
map_destroy(rr_mtd);
iounmap(rr_map.virt);
rr_map.virt = NULL;
}
MODULE_AUTHOR("PMC-Sierra, Inc");
MODULE_DESCRIPTION("MTD map driver for embedded PMC-Sierra MSP filesystem");
MODULE_LICENSE("GPL");
module_init(init_rrmap);
module_exit(cleanup_rrmap);