Root/target/linux/adm8668/files/drivers/mtd/maps/adm8668.c

1/*
2 * Copyright (C) 2010 Scott Nicholas <neutronscott@scottn.us>
3 * Copyright (C) 2006 Felix Fietkau <nbd@openwrt.org>
4 * Copyright (C) 2005 Waldemar Brodkorb <wbx@openwrt.org>
5 * Copyright (C) 2004 Florian Schirmer (jolt@tuxbox.org)
6 *
7 * original functions for finding root filesystem from Mike Baker
8 *
9 * This program is free software; you can redistribute it and/or modify it
10 * under the terms of the GNU General Public License as published by the
11 * Free Software Foundation; either version 2 of the License, or (at your
12 * option) any later version.
13 *
14 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
15 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
16 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
17 * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
20 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
21 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 *
25 * You should have received a copy of the GNU General Public License along
26 * with this program; if not, write to the Free Software Foundation, Inc.,
27 * 675 Mass Ave, Cambridge, MA 02139, USA.
28 *
29 *
30 * Copyright 2004, Broadcom Corporation
31 * All Rights Reserved.
32 *
33 * THIS SOFTWARE IS OFFERED "AS IS", AND BROADCOM GRANTS NO WARRANTIES OF ANY
34 * KIND, EXPRESS OR IMPLIED, BY STATUTE, COMMUNICATION OR OTHERWISE. BROADCOM
35 * SPECIFICALLY DISCLAIMS ANY IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS
36 * FOR A SPECIFIC PURPOSE OR NONINFRINGEMENT CONCERNING THIS SOFTWARE.
37 *
38 * Flash mapping for adm8668 boards
39 *
40 */
41
42#include <linux/module.h>
43#include <linux/types.h>
44#include <linux/kernel.h>
45#include <linux/sched.h>
46#include <linux/wait.h>
47#include <linux/mtd/mtd.h>
48#include <linux/mtd/map.h>
49#include <linux/slab.h>
50#ifdef CONFIG_MTD_PARTITIONS
51#include <linux/mtd/partitions.h>
52#endif
53#include <linux/crc32.h>
54#include <linux/magic.h>
55#include <asm/io.h>
56
57#define WINDOW_ADDR 0x10000000
58#define WINDOW_SIZE 0x800000
59#define BANKWIDTH 2
60
61/* first a little bit about the headers i need.. */
62
63/* just interested in part of the full struct */
64struct squashfs_super_block {
65        __le32 s_magic;
66        __le32 pad0[9]; /* it's not really padding */
67        __le64 bytes_used;
68};
69
70#define IH_MAGIC 0x56190527 /* Image Magic Number */
71struct uboot_header {
72    uint32_t ih_magic; /* Image Header Magic Number */
73    uint32_t ih_hcrc; /* Image Header CRC Checksum */
74    uint32_t ih_time; /* Image Creation Timestamp */
75    uint32_t ih_size; /* Image Data Size */
76    uint32_t ih_load; /* Data Load Address */
77    uint32_t ih_ep; /* Entry Point Address */
78    uint32_t ih_dcrc; /* Image Data CRC Checksum */
79    uint8_t ih_os; /* Operating System */
80    uint8_t ih_arch; /* CPU architecture */
81    uint8_t ih_type; /* Image Type */
82    uint8_t ih_comp; /* Compression Type */
83    char ih_name[32]; /* image name */
84};
85
86/************************************************/
87
88static struct mtd_info *adm8668_mtd;
89
90struct map_info adm8668_map = {
91    name: "adm8668-nor",
92    size: WINDOW_SIZE,
93    phys: WINDOW_ADDR,
94    bankwidth: BANKWIDTH,
95};
96
97#ifdef CONFIG_MTD_PARTITIONS
98
99/*
100 * Copied from mtdblock.c
101 *
102 * Cache stuff...
103 *
104 * Since typical flash erasable sectors are much larger than what Linux's
105 * buffer cache can handle, we must implement read-modify-write on flash
106 * sectors for each block write requests. To avoid over-erasing flash sectors
107 * and to speed things up, we locally cache a whole flash sector while it is
108 * being written to until a different sector is required.
109 */
110
111static void erase_callback(struct erase_info *done)
112{
113    wait_queue_head_t *wait_q = (wait_queue_head_t *)done->priv;
114    wake_up(wait_q);
115}
116
117static int erase_write (struct mtd_info *mtd, unsigned long pos,
118            int len, const char *buf)
119{
120    struct erase_info erase;
121    DECLARE_WAITQUEUE(wait, current);
122    wait_queue_head_t wait_q;
123    size_t retlen;
124    int ret;
125
126    /*
127     * First, let's erase the flash block.
128     */
129
130    init_waitqueue_head(&wait_q);
131    erase.mtd = mtd;
132    erase.callback = erase_callback;
133    erase.addr = pos;
134    erase.len = len;
135    erase.priv = (u_long)&wait_q;
136
137    set_current_state(TASK_INTERRUPTIBLE);
138    add_wait_queue(&wait_q, &wait);
139
140    ret = mtd->erase(mtd, &erase);
141    if (ret) {
142        set_current_state(TASK_RUNNING);
143        remove_wait_queue(&wait_q, &wait);
144        printk (KERN_WARNING "erase of region [0x%lx, 0x%x] "
145                     "on \"%s\" failed\n",
146            pos, len, mtd->name);
147        return ret;
148    }
149
150    schedule(); /* Wait for erase to finish. */
151    remove_wait_queue(&wait_q, &wait);
152
153    /*
154     * Next, write data to flash.
155     */
156
157    ret = mtd->write (mtd, pos, len, &retlen, buf);
158    if (ret)
159        return ret;
160    if (retlen != len)
161        return -EIO;
162    return 0;
163}
164
165/* decent defaults in case... shrug */
166static struct mtd_partition adm8668_parts[] = {
167    { name: "linux", offset: 0x40000, size: WINDOW_SIZE-0x40000, },
168    { name: "rootfs", offset: 0xe0000, size: 0x140000, },
169    { name: "uboot_env", offset: 0x20000, size: 0x20000, },
170    { name: NULL, },
171};
172
173/* in case i wanna change stuff later, and to clarify the math section... */
174#define PART_LINUX 0
175#define PART_ROOTFS 1
176#define NR_PARTS 3
177
178static int __init
179init_mtd_partitions(struct mtd_info *mtd, size_t size)
180{
181    struct uboot_header uhdr;
182    int off, blocksize;
183    size_t len, linux_len;
184    struct squashfs_super_block shdr;
185
186    blocksize = mtd->erasesize;
187    if (blocksize < 0x10000)
188        blocksize = 0x10000;
189
190    /* now find squashfs */
191    memset(&shdr, 0xe5, sizeof(shdr));
192    for (off = adm8668_parts[PART_LINUX].offset; off < size; off += blocksize) {
193        /*
194         * Read into buffer
195         */
196        if (mtd->read(mtd, off, sizeof(shdr), &len, (char *)&shdr) ||
197            len != sizeof(shdr))
198            continue;
199
200        if (shdr.s_magic == SQUASHFS_MAGIC) {
201            uint32_t fs_size = (uint32_t)shdr.bytes_used;
202
203            printk(KERN_INFO "%s: Filesystem type: squashfs, size=%dkB\n",
204                mtd->name, fs_size>>10);
205
206            /* Update rootfs based on the superblock info, and
207             * stretch to end of MTD. rootfs_split will split it */
208            adm8668_parts[PART_ROOTFS].offset = off;
209            adm8668_parts[PART_ROOTFS].size = mtd->size -
210                adm8668_parts[PART_ROOTFS].offset;
211
212            /* kernel ends where rootfs starts
213             * but we'll keep it full-length for upgrades */
214            linux_len = adm8668_parts[PART_LINUX+1].offset -
215                adm8668_parts[PART_LINUX].offset;
216#if 1
217            adm8668_parts[PART_LINUX].size = mtd->size -
218                adm8668_parts[PART_LINUX].offset;
219#else
220            adm8668_parts[PART_LINUX].size = linux_len;
221#endif
222            goto found;
223        }
224    }
225
226    printk(KERN_NOTICE
227           "%s: Couldn't find root filesystem\n",
228           mtd->name);
229    return NR_PARTS;
230
231 found:
232    if (mtd->read(mtd, adm8668_parts[PART_LINUX].offset, sizeof(uhdr), &len, (char *)&uhdr) ||
233        len != sizeof(uhdr))
234        return NR_PARTS;
235
236    /* that's odd. how'd ya boot it then */
237    if (uhdr.ih_magic != IH_MAGIC)
238        return NR_PARTS;
239
240    if (be32_to_cpu(uhdr.ih_size) != (linux_len - sizeof(uhdr))) {
241        unsigned char *block, *data = (unsigned char *)(WINDOW_ADDR | (adm8668_parts[PART_LINUX].offset + sizeof(struct uboot_header)) | 0xA0000000);
242
243        printk(KERN_NOTICE "Updating U-boot image:\n");
244        printk(KERN_NOTICE " old: [size: %8d crc32: 0x%08x]\n",
245            be32_to_cpu(uhdr.ih_size), be32_to_cpu(uhdr.ih_dcrc));
246
247        /* Update the data length & crc32 */
248        uhdr.ih_size = cpu_to_be32(linux_len - sizeof(uhdr));
249        uhdr.ih_dcrc = crc32_le(~0, data, linux_len - sizeof(uhdr)) ^ (~0);
250        uhdr.ih_dcrc = cpu_to_be32(uhdr.ih_dcrc);
251
252        printk(KERN_NOTICE " new: [size: %8d crc32: 0x%08x]\n",
253            be32_to_cpu(uhdr.ih_size), be32_to_cpu(uhdr.ih_dcrc));
254
255        /* update header's crc... */
256        uhdr.ih_hcrc = 0;
257        uhdr.ih_hcrc = crc32_le(~0, (unsigned char *)&uhdr,
258                sizeof(uhdr)) ^ (~0);
259        uhdr.ih_hcrc = cpu_to_be32(uhdr.ih_hcrc);
260
261        /* read first eraseblock from the image */
262        block = kmalloc(mtd->erasesize, GFP_KERNEL);
263        if (mtd->read(mtd, adm8668_parts[PART_LINUX].offset, mtd->erasesize, &len, block) || len != mtd->erasesize) {
264            printk("Error copying first eraseblock\n");
265            return 0;
266        }
267
268        /* Write updated header to the flash */
269        memcpy(block, &uhdr, sizeof(uhdr));
270        if (mtd->unlock)
271            mtd->unlock(mtd, off, mtd->erasesize);
272        erase_write(mtd, adm8668_parts[PART_LINUX].offset, mtd->erasesize, block);
273        if (mtd->sync)
274            mtd->sync(mtd);
275        kfree(block);
276        printk(KERN_NOTICE "Done\n");
277    }
278
279    return NR_PARTS;
280}
281
282#endif
283
284
285int __init init_adm8668_map(void)
286{
287#ifdef CONFIG_MTD_PARTITIONS
288    int nr_parts, ret;
289#endif
290
291    adm8668_map.virt = (unsigned long)ioremap(WINDOW_ADDR, WINDOW_SIZE);
292
293    if (!adm8668_map.virt) {
294        printk(KERN_ERR "Failed to ioremap\n");
295        return -EIO;
296    }
297
298    simple_map_init(&adm8668_map);
299    if (!(adm8668_mtd = do_map_probe("cfi_probe", &adm8668_map))) {
300        printk(KERN_ERR "cfi_probe failed\n");
301        iounmap((void *)adm8668_map.virt);
302        return -ENXIO;
303    }
304
305    adm8668_mtd->owner = THIS_MODULE;
306
307#ifdef CONFIG_MTD_PARTITIONS
308    nr_parts = init_mtd_partitions(adm8668_mtd, adm8668_mtd->size);
309    ret = add_mtd_partitions(adm8668_mtd, adm8668_parts, nr_parts);
310    if (ret) {
311        printk(KERN_ERR "Flash: add_mtd_partitions failed\n");
312        goto fail;
313    }
314#endif
315
316    return 0;
317
318 fail:
319    if (adm8668_mtd)
320        map_destroy(adm8668_mtd);
321    if (adm8668_map.virt)
322        iounmap((void *) adm8668_map.virt);
323    adm8668_map.virt = 0;
324    return ret;
325}
326
327void __exit cleanup_adm8668_map(void)
328{
329#ifdef CONFIG_MTD_PARTITIONS
330    del_mtd_partitions(adm8668_mtd);
331#endif
332    map_destroy(adm8668_mtd);
333    iounmap((void *) adm8668_map.virt);
334    adm8668_map.virt = 0;
335}
336
337module_init(init_adm8668_map);
338module_exit(cleanup_adm8668_map);
339
340MODULE_LICENSE("GPL");
341MODULE_AUTHOR("Scott Nicholas <neutronscott@scottn.us>");
342MODULE_DESCRIPTION("MTD map driver for ADM8668 NOR Flash");
343

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