1 /*
2 * Mapping of the rootfs in a physical region of memory
3 *
4 * Copyright (C) 2005-2007 PMC-Sierra Inc.
5 * Author: Andrew Hughes, Andrew_Hughes@pmc-sierra.com
6 *
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License as published by the
9 * Free Software Foundation; either version 2 of the License, or (at your
10 * option) any later version.
11 *
12 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
13 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
14 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
15 * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
16 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
17 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
18 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
19 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
20 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
21 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
22 *
23 * You should have received a copy of the GNU General Public License along
24 * with this program; if not, write to the Free Software Foundation, Inc.,
25 * 675 Mass Ave, Cambridge, MA 02139, USA.
26 */
27
28 #include <linux/module.h>
29 #include <linux/types.h>
30 #include <linux/kernel.h>
31 #include <linux/init.h>
32 #include <linux/slab.h>
33 #include <linux/fs.h>
34 #include <linux/root_dev.h>
35 #include <linux/mtd/mtd.h>
36 #include <linux/mtd/map.h>
37
38 #include <asm/io.h>
39
40 #include <msp_prom.h>
41
42 static struct mtd_info *rr_mtd;
43
44 struct map_info rr_map = {
45 .name = "ramroot",
46 .bankwidth = 4,
47 };
48
init_rrmap(void)49 static int __init init_rrmap(void)
50 {
51 void *ramroot_start;
52 unsigned long ramroot_size;
53
54 /* Check for supported rootfs types */
55 if (get_ramroot(&ramroot_start, &ramroot_size)) {
56 rr_map.phys = CPHYSADDR(ramroot_start);
57 rr_map.size = ramroot_size;
58
59 printk(KERN_NOTICE
60 "PMC embedded root device: 0x%08lx @ 0x%08lx\n",
61 rr_map.size, (unsigned long)rr_map.phys);
62 } else {
63 printk(KERN_ERR
64 "init_rrmap: no supported embedded rootfs detected!\n");
65 return -ENXIO;
66 }
67
68 /* Map rootfs to I/O space for block device driver */
69 rr_map.virt = ioremap(rr_map.phys, rr_map.size);
70 if (!rr_map.virt) {
71 printk(KERN_ERR "Failed to ioremap\n");
72 return -EIO;
73 }
74
75 simple_map_init(&rr_map);
76
77 rr_mtd = do_map_probe("map_ram", &rr_map);
78 if (rr_mtd) {
79 rr_mtd->owner = THIS_MODULE;
80
81 add_mtd_device(rr_mtd);
82
83 return 0;
84 }
85
86 iounmap(rr_map.virt);
87 return -ENXIO;
88 }
89
cleanup_rrmap(void)90 static void __exit cleanup_rrmap(void)
91 {
92 del_mtd_device(rr_mtd);
93 map_destroy(rr_mtd);
94
95 iounmap(rr_map.virt);
96 rr_map.virt = NULL;
97 }
98
99 MODULE_AUTHOR("PMC-Sierra, Inc");
100 MODULE_DESCRIPTION("MTD map driver for embedded PMC-Sierra MSP filesystem");
101 MODULE_LICENSE("GPL");
102
103 module_init(init_rrmap);
104 module_exit(cleanup_rrmap);
105