forked from Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
455 lines
11 KiB
455 lines
11 KiB
// SPDX-License-Identifier: GPL-2.0-only |
|
/* |
|
* Linux driver for SSFDC Flash Translation Layer (Read only) |
|
* © 2005 Eptar srl |
|
* Author: Claudio Lanconelli <[email protected]> |
|
* |
|
* Based on NTFL and MTDBLOCK_RO drivers |
|
*/ |
|
|
|
#include <linux/kernel.h> |
|
#include <linux/module.h> |
|
#include <linux/init.h> |
|
#include <linux/slab.h> |
|
#include <linux/hdreg.h> |
|
#include <linux/mtd/mtd.h> |
|
#include <linux/mtd/rawnand.h> |
|
#include <linux/mtd/blktrans.h> |
|
|
|
struct ssfdcr_record { |
|
struct mtd_blktrans_dev mbd; |
|
int usecount; |
|
unsigned char heads; |
|
unsigned char sectors; |
|
unsigned short cylinders; |
|
int cis_block; /* block n. containing CIS/IDI */ |
|
int erase_size; /* phys_block_size */ |
|
unsigned short *logic_block_map; /* all zones (max 8192 phys blocks on |
|
the 128MiB) */ |
|
int map_len; /* n. phys_blocks on the card */ |
|
}; |
|
|
|
#define SSFDCR_MAJOR 257 |
|
#define SSFDCR_PARTN_BITS 3 |
|
|
|
#define SECTOR_SIZE 512 |
|
#define SECTOR_SHIFT 9 |
|
#define OOB_SIZE 16 |
|
|
|
#define MAX_LOGIC_BLK_PER_ZONE 1000 |
|
#define MAX_PHYS_BLK_PER_ZONE 1024 |
|
|
|
#define KiB(x) ( (x) * 1024L ) |
|
#define MiB(x) ( KiB(x) * 1024L ) |
|
|
|
/** CHS Table |
|
1MiB 2MiB 4MiB 8MiB 16MiB 32MiB 64MiB 128MiB |
|
NCylinder 125 125 250 250 500 500 500 500 |
|
NHead 4 4 4 4 4 8 8 16 |
|
NSector 4 8 8 16 16 16 32 32 |
|
SumSector 2,000 4,000 8,000 16,000 32,000 64,000 128,000 256,000 |
|
SectorSize 512 512 512 512 512 512 512 512 |
|
**/ |
|
|
|
typedef struct { |
|
unsigned long size; |
|
unsigned short cyl; |
|
unsigned char head; |
|
unsigned char sec; |
|
} chs_entry_t; |
|
|
|
/* Must be ordered by size */ |
|
static const chs_entry_t chs_table[] = { |
|
{ MiB( 1), 125, 4, 4 }, |
|
{ MiB( 2), 125, 4, 8 }, |
|
{ MiB( 4), 250, 4, 8 }, |
|
{ MiB( 8), 250, 4, 16 }, |
|
{ MiB( 16), 500, 4, 16 }, |
|
{ MiB( 32), 500, 8, 16 }, |
|
{ MiB( 64), 500, 8, 32 }, |
|
{ MiB(128), 500, 16, 32 }, |
|
{ 0 }, |
|
}; |
|
|
|
static int get_chs(unsigned long size, unsigned short *cyl, unsigned char *head, |
|
unsigned char *sec) |
|
{ |
|
int k; |
|
int found = 0; |
|
|
|
k = 0; |
|
while (chs_table[k].size > 0 && size > chs_table[k].size) |
|
k++; |
|
|
|
if (chs_table[k].size > 0) { |
|
if (cyl) |
|
*cyl = chs_table[k].cyl; |
|
if (head) |
|
*head = chs_table[k].head; |
|
if (sec) |
|
*sec = chs_table[k].sec; |
|
found = 1; |
|
} |
|
|
|
return found; |
|
} |
|
|
|
/* These bytes are the signature for the CIS/IDI sector */ |
|
static const uint8_t cis_numbers[] = { |
|
0x01, 0x03, 0xD9, 0x01, 0xFF, 0x18, 0x02, 0xDF, 0x01, 0x20 |
|
}; |
|
|
|
/* Read and check for a valid CIS sector */ |
|
static int get_valid_cis_sector(struct mtd_info *mtd) |
|
{ |
|
int ret, k, cis_sector; |
|
size_t retlen; |
|
loff_t offset; |
|
uint8_t *sect_buf; |
|
|
|
cis_sector = -1; |
|
|
|
sect_buf = kmalloc(SECTOR_SIZE, GFP_KERNEL); |
|
if (!sect_buf) |
|
goto out; |
|
|
|
/* |
|
* Look for CIS/IDI sector on the first GOOD block (give up after 4 bad |
|
* blocks). If the first good block doesn't contain CIS number the flash |
|
* is not SSFDC formatted |
|
*/ |
|
for (k = 0, offset = 0; k < 4; k++, offset += mtd->erasesize) { |
|
if (mtd_block_isbad(mtd, offset)) { |
|
ret = mtd_read(mtd, offset, SECTOR_SIZE, &retlen, |
|
sect_buf); |
|
|
|
/* CIS pattern match on the sector buffer */ |
|
if (ret < 0 || retlen != SECTOR_SIZE) { |
|
printk(KERN_WARNING |
|
"SSFDC_RO:can't read CIS/IDI sector\n"); |
|
} else if (!memcmp(sect_buf, cis_numbers, |
|
sizeof(cis_numbers))) { |
|
/* Found */ |
|
cis_sector = (int)(offset >> SECTOR_SHIFT); |
|
} else { |
|
pr_debug("SSFDC_RO: CIS/IDI sector not found" |
|
" on %s (mtd%d)\n", mtd->name, |
|
mtd->index); |
|
} |
|
break; |
|
} |
|
} |
|
|
|
kfree(sect_buf); |
|
out: |
|
return cis_sector; |
|
} |
|
|
|
/* Read physical sector (wrapper to MTD_READ) */ |
|
static int read_physical_sector(struct mtd_info *mtd, uint8_t *sect_buf, |
|
int sect_no) |
|
{ |
|
int ret; |
|
size_t retlen; |
|
loff_t offset = (loff_t)sect_no << SECTOR_SHIFT; |
|
|
|
ret = mtd_read(mtd, offset, SECTOR_SIZE, &retlen, sect_buf); |
|
if (ret < 0 || retlen != SECTOR_SIZE) |
|
return -1; |
|
|
|
return 0; |
|
} |
|
|
|
/* Read redundancy area (wrapper to MTD_READ_OOB */ |
|
static int read_raw_oob(struct mtd_info *mtd, loff_t offs, uint8_t *buf) |
|
{ |
|
struct mtd_oob_ops ops; |
|
int ret; |
|
|
|
ops.mode = MTD_OPS_RAW; |
|
ops.ooboffs = 0; |
|
ops.ooblen = OOB_SIZE; |
|
ops.oobbuf = buf; |
|
ops.datbuf = NULL; |
|
|
|
ret = mtd_read_oob(mtd, offs, &ops); |
|
if (ret < 0 || ops.oobretlen != OOB_SIZE) |
|
return -1; |
|
|
|
return 0; |
|
} |
|
|
|
/* Parity calculator on a word of n bit size */ |
|
static int get_parity(int number, int size) |
|
{ |
|
int k; |
|
int parity; |
|
|
|
parity = 1; |
|
for (k = 0; k < size; k++) { |
|
parity += (number >> k); |
|
parity &= 1; |
|
} |
|
return parity; |
|
} |
|
|
|
/* Read and validate the logical block address field stored in the OOB */ |
|
static int get_logical_address(uint8_t *oob_buf) |
|
{ |
|
int block_address, parity; |
|
int offset[2] = {6, 11}; /* offset of the 2 address fields within OOB */ |
|
int j; |
|
int ok = 0; |
|
|
|
/* |
|
* Look for the first valid logical address |
|
* Valid address has fixed pattern on most significant bits and |
|
* parity check |
|
*/ |
|
for (j = 0; j < ARRAY_SIZE(offset); j++) { |
|
block_address = ((int)oob_buf[offset[j]] << 8) | |
|
oob_buf[offset[j]+1]; |
|
|
|
/* Check for the signature bits in the address field (MSBits) */ |
|
if ((block_address & ~0x7FF) == 0x1000) { |
|
parity = block_address & 0x01; |
|
block_address &= 0x7FF; |
|
block_address >>= 1; |
|
|
|
if (get_parity(block_address, 10) != parity) { |
|
pr_debug("SSFDC_RO: logical address field%d" |
|
"parity error(0x%04X)\n", j+1, |
|
block_address); |
|
} else { |
|
ok = 1; |
|
break; |
|
} |
|
} |
|
} |
|
|
|
if (!ok) |
|
block_address = -2; |
|
|
|
pr_debug("SSFDC_RO: get_logical_address() %d\n", |
|
block_address); |
|
|
|
return block_address; |
|
} |
|
|
|
/* Build the logic block map */ |
|
static int build_logical_block_map(struct ssfdcr_record *ssfdc) |
|
{ |
|
unsigned long offset; |
|
uint8_t oob_buf[OOB_SIZE]; |
|
int ret, block_address, phys_block; |
|
struct mtd_info *mtd = ssfdc->mbd.mtd; |
|
|
|
pr_debug("SSFDC_RO: build_block_map() nblks=%d (%luK)\n", |
|
ssfdc->map_len, |
|
(unsigned long)ssfdc->map_len * ssfdc->erase_size / 1024); |
|
|
|
/* Scan every physical block, skip CIS block */ |
|
for (phys_block = ssfdc->cis_block + 1; phys_block < ssfdc->map_len; |
|
phys_block++) { |
|
offset = (unsigned long)phys_block * ssfdc->erase_size; |
|
if (mtd_block_isbad(mtd, offset)) |
|
continue; /* skip bad blocks */ |
|
|
|
ret = read_raw_oob(mtd, offset, oob_buf); |
|
if (ret < 0) { |
|
pr_debug("SSFDC_RO: mtd read_oob() failed at %lu\n", |
|
offset); |
|
return -1; |
|
} |
|
block_address = get_logical_address(oob_buf); |
|
|
|
/* Skip invalid addresses */ |
|
if (block_address >= 0 && |
|
block_address < MAX_LOGIC_BLK_PER_ZONE) { |
|
int zone_index; |
|
|
|
zone_index = phys_block / MAX_PHYS_BLK_PER_ZONE; |
|
block_address += zone_index * MAX_LOGIC_BLK_PER_ZONE; |
|
ssfdc->logic_block_map[block_address] = |
|
(unsigned short)phys_block; |
|
|
|
pr_debug("SSFDC_RO: build_block_map() phys_block=%d," |
|
"logic_block_addr=%d, zone=%d\n", |
|
phys_block, block_address, zone_index); |
|
} |
|
} |
|
return 0; |
|
} |
|
|
|
static void ssfdcr_add_mtd(struct mtd_blktrans_ops *tr, struct mtd_info *mtd) |
|
{ |
|
struct ssfdcr_record *ssfdc; |
|
int cis_sector; |
|
|
|
/* Check for small page NAND flash */ |
|
if (!mtd_type_is_nand(mtd) || mtd->oobsize != OOB_SIZE || |
|
mtd->size > UINT_MAX) |
|
return; |
|
|
|
/* Check for SSDFC format by reading CIS/IDI sector */ |
|
cis_sector = get_valid_cis_sector(mtd); |
|
if (cis_sector == -1) |
|
return; |
|
|
|
ssfdc = kzalloc(sizeof(struct ssfdcr_record), GFP_KERNEL); |
|
if (!ssfdc) |
|
return; |
|
|
|
ssfdc->mbd.mtd = mtd; |
|
ssfdc->mbd.devnum = -1; |
|
ssfdc->mbd.tr = tr; |
|
ssfdc->mbd.readonly = 1; |
|
|
|
ssfdc->cis_block = cis_sector / (mtd->erasesize >> SECTOR_SHIFT); |
|
ssfdc->erase_size = mtd->erasesize; |
|
ssfdc->map_len = (u32)mtd->size / mtd->erasesize; |
|
|
|
pr_debug("SSFDC_RO: cis_block=%d,erase_size=%d,map_len=%d,n_zones=%d\n", |
|
ssfdc->cis_block, ssfdc->erase_size, ssfdc->map_len, |
|
DIV_ROUND_UP(ssfdc->map_len, MAX_PHYS_BLK_PER_ZONE)); |
|
|
|
/* Set geometry */ |
|
ssfdc->heads = 16; |
|
ssfdc->sectors = 32; |
|
get_chs(mtd->size, NULL, &ssfdc->heads, &ssfdc->sectors); |
|
ssfdc->cylinders = (unsigned short)(((u32)mtd->size >> SECTOR_SHIFT) / |
|
((long)ssfdc->sectors * (long)ssfdc->heads)); |
|
|
|
pr_debug("SSFDC_RO: using C:%d H:%d S:%d == %ld sects\n", |
|
ssfdc->cylinders, ssfdc->heads , ssfdc->sectors, |
|
(long)ssfdc->cylinders * (long)ssfdc->heads * |
|
(long)ssfdc->sectors); |
|
|
|
ssfdc->mbd.size = (long)ssfdc->heads * (long)ssfdc->cylinders * |
|
(long)ssfdc->sectors; |
|
|
|
/* Allocate logical block map */ |
|
ssfdc->logic_block_map = |
|
kmalloc_array(ssfdc->map_len, |
|
sizeof(ssfdc->logic_block_map[0]), GFP_KERNEL); |
|
if (!ssfdc->logic_block_map) |
|
goto out_err; |
|
memset(ssfdc->logic_block_map, 0xff, sizeof(ssfdc->logic_block_map[0]) * |
|
ssfdc->map_len); |
|
|
|
/* Build logical block map */ |
|
if (build_logical_block_map(ssfdc) < 0) |
|
goto out_err; |
|
|
|
/* Register device + partitions */ |
|
if (add_mtd_blktrans_dev(&ssfdc->mbd)) |
|
goto out_err; |
|
|
|
printk(KERN_INFO "SSFDC_RO: Found ssfdc%c on mtd%d (%s)\n", |
|
ssfdc->mbd.devnum + 'a', mtd->index, mtd->name); |
|
return; |
|
|
|
out_err: |
|
kfree(ssfdc->logic_block_map); |
|
kfree(ssfdc); |
|
} |
|
|
|
static void ssfdcr_remove_dev(struct mtd_blktrans_dev *dev) |
|
{ |
|
struct ssfdcr_record *ssfdc = (struct ssfdcr_record *)dev; |
|
|
|
pr_debug("SSFDC_RO: remove_dev (i=%d)\n", dev->devnum); |
|
|
|
del_mtd_blktrans_dev(dev); |
|
kfree(ssfdc->logic_block_map); |
|
} |
|
|
|
static int ssfdcr_readsect(struct mtd_blktrans_dev *dev, |
|
unsigned long logic_sect_no, char *buf) |
|
{ |
|
struct ssfdcr_record *ssfdc = (struct ssfdcr_record *)dev; |
|
int sectors_per_block, offset, block_address; |
|
|
|
sectors_per_block = ssfdc->erase_size >> SECTOR_SHIFT; |
|
offset = (int)(logic_sect_no % sectors_per_block); |
|
block_address = (int)(logic_sect_no / sectors_per_block); |
|
|
|
pr_debug("SSFDC_RO: ssfdcr_readsect(%lu) sec_per_blk=%d, ofst=%d," |
|
" block_addr=%d\n", logic_sect_no, sectors_per_block, offset, |
|
block_address); |
|
|
|
BUG_ON(block_address >= ssfdc->map_len); |
|
|
|
block_address = ssfdc->logic_block_map[block_address]; |
|
|
|
pr_debug("SSFDC_RO: ssfdcr_readsect() phys_block_addr=%d\n", |
|
block_address); |
|
|
|
if (block_address < 0xffff) { |
|
unsigned long sect_no; |
|
|
|
sect_no = (unsigned long)block_address * sectors_per_block + |
|
offset; |
|
|
|
pr_debug("SSFDC_RO: ssfdcr_readsect() phys_sect_no=%lu\n", |
|
sect_no); |
|
|
|
if (read_physical_sector(ssfdc->mbd.mtd, buf, sect_no) < 0) |
|
return -EIO; |
|
} else { |
|
memset(buf, 0xff, SECTOR_SIZE); |
|
} |
|
|
|
return 0; |
|
} |
|
|
|
static int ssfdcr_getgeo(struct mtd_blktrans_dev *dev, struct hd_geometry *geo) |
|
{ |
|
struct ssfdcr_record *ssfdc = (struct ssfdcr_record *)dev; |
|
|
|
pr_debug("SSFDC_RO: ssfdcr_getgeo() C=%d, H=%d, S=%d\n", |
|
ssfdc->cylinders, ssfdc->heads, ssfdc->sectors); |
|
|
|
geo->heads = ssfdc->heads; |
|
geo->sectors = ssfdc->sectors; |
|
geo->cylinders = ssfdc->cylinders; |
|
|
|
return 0; |
|
} |
|
|
|
/**************************************************************************** |
|
* |
|
* Module stuff |
|
* |
|
****************************************************************************/ |
|
|
|
static struct mtd_blktrans_ops ssfdcr_tr = { |
|
.name = "ssfdc", |
|
.major = SSFDCR_MAJOR, |
|
.part_bits = SSFDCR_PARTN_BITS, |
|
.blksize = SECTOR_SIZE, |
|
.getgeo = ssfdcr_getgeo, |
|
.readsect = ssfdcr_readsect, |
|
.add_mtd = ssfdcr_add_mtd, |
|
.remove_dev = ssfdcr_remove_dev, |
|
.owner = THIS_MODULE, |
|
}; |
|
|
|
static int __init init_ssfdcr(void) |
|
{ |
|
printk(KERN_INFO "SSFDC read-only Flash Translation layer\n"); |
|
|
|
return register_mtd_blktrans(&ssfdcr_tr); |
|
} |
|
|
|
static void __exit cleanup_ssfdcr(void) |
|
{ |
|
deregister_mtd_blktrans(&ssfdcr_tr); |
|
} |
|
|
|
module_init(init_ssfdcr); |
|
module_exit(cleanup_ssfdcr); |
|
|
|
MODULE_LICENSE("GPL"); |
|
MODULE_AUTHOR("Claudio Lanconelli <[email protected]>"); |
|
MODULE_DESCRIPTION("Flash Translation Layer for read-only SSFDC SmartMedia card");
|
|
|