11da177e4SLinus Torvalds /*
21da177e4SLinus Torvalds * mtdram - a test mtd device
31da177e4SLinus Torvalds * Author: Alexander Larsson <alex@cendio.se>
41da177e4SLinus Torvalds *
51da177e4SLinus Torvalds * Copyright (c) 1999 Alexander Larsson <alex@cendio.se>
6c13cbf3bSJoern Engel * Copyright (c) 2005 Joern Engel <joern@wh.fh-wedel.de>
71da177e4SLinus Torvalds *
81da177e4SLinus Torvalds * This code is GPL
91da177e4SLinus Torvalds *
101da177e4SLinus Torvalds */
111da177e4SLinus Torvalds
121da177e4SLinus Torvalds #include <linux/module.h>
131da177e4SLinus Torvalds #include <linux/slab.h>
141da177e4SLinus Torvalds #include <linux/ioport.h>
151da177e4SLinus Torvalds #include <linux/vmalloc.h>
16877b58ebSNicolas Pitre #include <linux/mm.h>
171da177e4SLinus Torvalds #include <linux/init.h>
181da177e4SLinus Torvalds #include <linux/mtd/mtd.h>
19456d9fc9SAdrian Bunk #include <linux/mtd/mtdram.h>
201da177e4SLinus Torvalds
211da177e4SLinus Torvalds static unsigned long total_size = CONFIG_MTDRAM_TOTAL_SIZE;
221da177e4SLinus Torvalds static unsigned long erase_size = CONFIG_MTDRAM_ERASE_SIZE;
23c67682c5SAlexander Stein static unsigned long writebuf_size = 64;
24c13cbf3bSJoern Engel #define MTDRAM_TOTAL_SIZE (total_size * 1024)
25c13cbf3bSJoern Engel #define MTDRAM_ERASE_SIZE (erase_size * 1024)
26c13cbf3bSJoern Engel
271da177e4SLinus Torvalds module_param(total_size, ulong, 0);
281da177e4SLinus Torvalds MODULE_PARM_DESC(total_size, "Total device size in KiB");
291da177e4SLinus Torvalds module_param(erase_size, ulong, 0);
301da177e4SLinus Torvalds MODULE_PARM_DESC(erase_size, "Device erase block size in KiB");
31c67682c5SAlexander Stein module_param(writebuf_size, ulong, 0);
32c67682c5SAlexander Stein MODULE_PARM_DESC(writebuf_size, "Device write buf size in Bytes (Default: 64)");
331da177e4SLinus Torvalds
341da177e4SLinus Torvalds // We could store these in the mtd structure, but we only support 1 device..
351da177e4SLinus Torvalds static struct mtd_info *mtd_info;
361da177e4SLinus Torvalds
check_offs_len(struct mtd_info * mtd,loff_t ofs,uint64_t len)37ab84fce5SDongsheng Yang static int check_offs_len(struct mtd_info *mtd, loff_t ofs, uint64_t len)
38ab84fce5SDongsheng Yang {
39ab84fce5SDongsheng Yang int ret = 0;
40ab84fce5SDongsheng Yang
41ab84fce5SDongsheng Yang /* Start address must align on block boundary */
42ab84fce5SDongsheng Yang if (mtd_mod_by_eb(ofs, mtd)) {
43ab84fce5SDongsheng Yang pr_debug("%s: unaligned address\n", __func__);
44ab84fce5SDongsheng Yang ret = -EINVAL;
45ab84fce5SDongsheng Yang }
46ab84fce5SDongsheng Yang
47ab84fce5SDongsheng Yang /* Length must align on block boundary */
48ab84fce5SDongsheng Yang if (mtd_mod_by_eb(len, mtd)) {
49ab84fce5SDongsheng Yang pr_debug("%s: length not block aligned\n", __func__);
50ab84fce5SDongsheng Yang ret = -EINVAL;
51ab84fce5SDongsheng Yang }
52ab84fce5SDongsheng Yang
53ab84fce5SDongsheng Yang return ret;
54ab84fce5SDongsheng Yang }
55ab84fce5SDongsheng Yang
ram_erase(struct mtd_info * mtd,struct erase_info * instr)56c13cbf3bSJoern Engel static int ram_erase(struct mtd_info *mtd, struct erase_info *instr)
571da177e4SLinus Torvalds {
58ab84fce5SDongsheng Yang if (check_offs_len(mtd, instr->addr, instr->len))
59ab84fce5SDongsheng Yang return -EINVAL;
601da177e4SLinus Torvalds memset((char *)mtd->priv + instr->addr, 0xff, instr->len);
61*e7bfb3fdSBoris Brezillon
621da177e4SLinus Torvalds return 0;
631da177e4SLinus Torvalds }
641da177e4SLinus Torvalds
ram_point(struct mtd_info * mtd,loff_t from,size_t len,size_t * retlen,void ** virt,resource_size_t * phys)65c13cbf3bSJoern Engel static int ram_point(struct mtd_info *mtd, loff_t from, size_t len,
66a98889f3SJared Hulbert size_t *retlen, void **virt, resource_size_t *phys)
671da177e4SLinus Torvalds {
68a98889f3SJared Hulbert *virt = mtd->priv + from;
691da177e4SLinus Torvalds *retlen = len;
70877b58ebSNicolas Pitre
71877b58ebSNicolas Pitre if (phys) {
72877b58ebSNicolas Pitre /* limit retlen to the number of contiguous physical pages */
73877b58ebSNicolas Pitre unsigned long page_ofs = offset_in_page(*virt);
74877b58ebSNicolas Pitre void *addr = *virt - page_ofs;
75877b58ebSNicolas Pitre unsigned long pfn1, pfn0 = vmalloc_to_pfn(addr);
76877b58ebSNicolas Pitre
77877b58ebSNicolas Pitre *phys = __pfn_to_phys(pfn0) + page_ofs;
78877b58ebSNicolas Pitre len += page_ofs;
79877b58ebSNicolas Pitre while (len > PAGE_SIZE) {
80877b58ebSNicolas Pitre len -= PAGE_SIZE;
81877b58ebSNicolas Pitre addr += PAGE_SIZE;
82877b58ebSNicolas Pitre pfn0++;
83877b58ebSNicolas Pitre pfn1 = vmalloc_to_pfn(addr);
84877b58ebSNicolas Pitre if (pfn1 != pfn0) {
85877b58ebSNicolas Pitre *retlen = addr - *virt;
86877b58ebSNicolas Pitre break;
87877b58ebSNicolas Pitre }
88877b58ebSNicolas Pitre }
89877b58ebSNicolas Pitre }
90877b58ebSNicolas Pitre
911da177e4SLinus Torvalds return 0;
921da177e4SLinus Torvalds }
931da177e4SLinus Torvalds
ram_unpoint(struct mtd_info * mtd,loff_t from,size_t len)945e4e6e3fSArtem Bityutskiy static int ram_unpoint(struct mtd_info *mtd, loff_t from, size_t len)
951da177e4SLinus Torvalds {
965e4e6e3fSArtem Bityutskiy return 0;
971da177e4SLinus Torvalds }
981da177e4SLinus Torvalds
ram_read(struct mtd_info * mtd,loff_t from,size_t len,size_t * retlen,u_char * buf)991da177e4SLinus Torvalds static int ram_read(struct mtd_info *mtd, loff_t from, size_t len,
1001da177e4SLinus Torvalds size_t *retlen, u_char *buf)
1011da177e4SLinus Torvalds {
1021da177e4SLinus Torvalds memcpy(buf, mtd->priv + from, len);
1031da177e4SLinus Torvalds *retlen = len;
1041da177e4SLinus Torvalds return 0;
1051da177e4SLinus Torvalds }
1061da177e4SLinus Torvalds
ram_write(struct mtd_info * mtd,loff_t to,size_t len,size_t * retlen,const u_char * buf)1071da177e4SLinus Torvalds static int ram_write(struct mtd_info *mtd, loff_t to, size_t len,
1081da177e4SLinus Torvalds size_t *retlen, const u_char *buf)
1091da177e4SLinus Torvalds {
1101da177e4SLinus Torvalds memcpy((char *)mtd->priv + to, buf, len);
1111da177e4SLinus Torvalds *retlen = len;
1121da177e4SLinus Torvalds return 0;
1131da177e4SLinus Torvalds }
1141da177e4SLinus Torvalds
cleanup_mtdram(void)1151da177e4SLinus Torvalds static void __exit cleanup_mtdram(void)
1161da177e4SLinus Torvalds {
1171da177e4SLinus Torvalds if (mtd_info) {
118ee0e87b1SJamie Iles mtd_device_unregister(mtd_info);
1191da177e4SLinus Torvalds vfree(mtd_info->priv);
1201da177e4SLinus Torvalds kfree(mtd_info);
1211da177e4SLinus Torvalds }
1221da177e4SLinus Torvalds }
1231da177e4SLinus Torvalds
mtdram_init_device(struct mtd_info * mtd,void * mapped_address,unsigned long size,const char * name)1241da177e4SLinus Torvalds int mtdram_init_device(struct mtd_info *mtd, void *mapped_address,
1250a8899b3SBrian Norris unsigned long size, const char *name)
1261da177e4SLinus Torvalds {
1271da177e4SLinus Torvalds memset(mtd, 0, sizeof(*mtd));
1281da177e4SLinus Torvalds
1291da177e4SLinus Torvalds /* Setup the MTD structure */
1301da177e4SLinus Torvalds mtd->name = name;
13121c8db9eSDavid Woodhouse mtd->type = MTD_RAM;
1321da177e4SLinus Torvalds mtd->flags = MTD_CAP_RAM;
1331da177e4SLinus Torvalds mtd->size = size;
134783ed81fSArtem B. Bityutskiy mtd->writesize = 1;
135c67682c5SAlexander Stein mtd->writebufsize = writebuf_size;
1361da177e4SLinus Torvalds mtd->erasesize = MTDRAM_ERASE_SIZE;
1371da177e4SLinus Torvalds mtd->priv = mapped_address;
1381da177e4SLinus Torvalds
1391da177e4SLinus Torvalds mtd->owner = THIS_MODULE;
1403c3c10bbSArtem Bityutskiy mtd->_erase = ram_erase;
1413c3c10bbSArtem Bityutskiy mtd->_point = ram_point;
1423c3c10bbSArtem Bityutskiy mtd->_unpoint = ram_unpoint;
1433c3c10bbSArtem Bityutskiy mtd->_read = ram_read;
1443c3c10bbSArtem Bityutskiy mtd->_write = ram_write;
1451da177e4SLinus Torvalds
146ee0e87b1SJamie Iles if (mtd_device_register(mtd, NULL, 0))
1471da177e4SLinus Torvalds return -EIO;
1481da177e4SLinus Torvalds
1491da177e4SLinus Torvalds return 0;
1501da177e4SLinus Torvalds }
1511da177e4SLinus Torvalds
init_mtdram(void)1521da177e4SLinus Torvalds static int __init init_mtdram(void)
1531da177e4SLinus Torvalds {
1541da177e4SLinus Torvalds void *addr;
1551da177e4SLinus Torvalds int err;
1561da177e4SLinus Torvalds
157c13cbf3bSJoern Engel if (!total_size)
158c13cbf3bSJoern Engel return -EINVAL;
1591da177e4SLinus Torvalds
1601da177e4SLinus Torvalds /* Allocate some memory */
1611da177e4SLinus Torvalds mtd_info = kmalloc(sizeof(struct mtd_info), GFP_KERNEL);
1621da177e4SLinus Torvalds if (!mtd_info)
1631da177e4SLinus Torvalds return -ENOMEM;
1641da177e4SLinus Torvalds
1651da177e4SLinus Torvalds addr = vmalloc(MTDRAM_TOTAL_SIZE);
1661da177e4SLinus Torvalds if (!addr) {
1671da177e4SLinus Torvalds kfree(mtd_info);
1681da177e4SLinus Torvalds mtd_info = NULL;
1691da177e4SLinus Torvalds return -ENOMEM;
1701da177e4SLinus Torvalds }
171c13cbf3bSJoern Engel err = mtdram_init_device(mtd_info, addr, MTDRAM_TOTAL_SIZE, "mtdram test device");
172c13cbf3bSJoern Engel if (err) {
1731da177e4SLinus Torvalds vfree(addr);
1741da177e4SLinus Torvalds kfree(mtd_info);
1751da177e4SLinus Torvalds mtd_info = NULL;
1761da177e4SLinus Torvalds return err;
1771da177e4SLinus Torvalds }
1781da177e4SLinus Torvalds memset(mtd_info->priv, 0xff, MTDRAM_TOTAL_SIZE);
1791da177e4SLinus Torvalds return err;
1801da177e4SLinus Torvalds }
1811da177e4SLinus Torvalds
1821da177e4SLinus Torvalds module_init(init_mtdram);
1831da177e4SLinus Torvalds module_exit(cleanup_mtdram);
1841da177e4SLinus Torvalds
1851da177e4SLinus Torvalds MODULE_LICENSE("GPL");
1861da177e4SLinus Torvalds MODULE_AUTHOR("Alexander Larsson <alexl@redhat.com>");
1871da177e4SLinus Torvalds MODULE_DESCRIPTION("Simulated MTD driver for testing");
188