alistair23-linux/drivers/mtd/devices/lart.c
Artem Bityutskiy bcb1d23871 mtd: move zero length verification to MTD API functions
In many places in drivers we verify for the zero length, but this is very
inconsistent across drivers. This is obviously the right thing to do, though.
This patch moves the check to the MTD API functions instead and removes a lot
of duplication.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Reviewed-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-03-27 00:32:19 +01:00

686 lines
18 KiB
C

/*
* MTD driver for the 28F160F3 Flash Memory (non-CFI) on LART.
*
* Author: Abraham vd Merwe <abraham@2d3d.co.za>
*
* Copyright (c) 2001, 2d3D, Inc.
*
* This code is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* References:
*
* [1] 3 Volt Fast Boot Block Flash Memory" Intel Datasheet
* - Order Number: 290644-005
* - January 2000
*
* [2] MTD internal API documentation
* - http://www.linux-mtd.infradead.org/
*
* Limitations:
*
* Even though this driver is written for 3 Volt Fast Boot
* Block Flash Memory, it is rather specific to LART. With
* Minor modifications, notably the without data/address line
* mangling and different bus settings, etc. it should be
* trivial to adapt to other platforms.
*
* If somebody would sponsor me a different board, I'll
* adapt the driver (:
*/
/* debugging */
//#define LART_DEBUG
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/init.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/partitions.h>
#ifndef CONFIG_SA1100_LART
#error This is for LART architecture only
#endif
static char module_name[] = "lart";
/*
* These values is specific to 28Fxxxx3 flash memory.
* See section 2.3.1 in "3 Volt Fast Boot Block Flash Memory" Intel Datasheet
*/
#define FLASH_BLOCKSIZE_PARAM (4096 * BUSWIDTH)
#define FLASH_NUMBLOCKS_16m_PARAM 8
#define FLASH_NUMBLOCKS_8m_PARAM 8
/*
* These values is specific to 28Fxxxx3 flash memory.
* See section 2.3.2 in "3 Volt Fast Boot Block Flash Memory" Intel Datasheet
*/
#define FLASH_BLOCKSIZE_MAIN (32768 * BUSWIDTH)
#define FLASH_NUMBLOCKS_16m_MAIN 31
#define FLASH_NUMBLOCKS_8m_MAIN 15
/*
* These values are specific to LART
*/
/* general */
#define BUSWIDTH 4 /* don't change this - a lot of the code _will_ break if you change this */
#define FLASH_OFFSET 0xe8000000 /* see linux/arch/arm/mach-sa1100/lart.c */
/* blob */
#define NUM_BLOB_BLOCKS FLASH_NUMBLOCKS_16m_PARAM
#define BLOB_START 0x00000000
#define BLOB_LEN (NUM_BLOB_BLOCKS * FLASH_BLOCKSIZE_PARAM)
/* kernel */
#define NUM_KERNEL_BLOCKS 7
#define KERNEL_START (BLOB_START + BLOB_LEN)
#define KERNEL_LEN (NUM_KERNEL_BLOCKS * FLASH_BLOCKSIZE_MAIN)
/* initial ramdisk */
#define NUM_INITRD_BLOCKS 24
#define INITRD_START (KERNEL_START + KERNEL_LEN)
#define INITRD_LEN (NUM_INITRD_BLOCKS * FLASH_BLOCKSIZE_MAIN)
/*
* See section 4.0 in "3 Volt Fast Boot Block Flash Memory" Intel Datasheet
*/
#define READ_ARRAY 0x00FF00FF /* Read Array/Reset */
#define READ_ID_CODES 0x00900090 /* Read Identifier Codes */
#define ERASE_SETUP 0x00200020 /* Block Erase */
#define ERASE_CONFIRM 0x00D000D0 /* Block Erase and Program Resume */
#define PGM_SETUP 0x00400040 /* Program */
#define STATUS_READ 0x00700070 /* Read Status Register */
#define STATUS_CLEAR 0x00500050 /* Clear Status Register */
#define STATUS_BUSY 0x00800080 /* Write State Machine Status (WSMS) */
#define STATUS_ERASE_ERR 0x00200020 /* Erase Status (ES) */
#define STATUS_PGM_ERR 0x00100010 /* Program Status (PS) */
/*
* See section 4.2 in "3 Volt Fast Boot Block Flash Memory" Intel Datasheet
*/
#define FLASH_MANUFACTURER 0x00890089
#define FLASH_DEVICE_8mbit_TOP 0x88f188f1
#define FLASH_DEVICE_8mbit_BOTTOM 0x88f288f2
#define FLASH_DEVICE_16mbit_TOP 0x88f388f3
#define FLASH_DEVICE_16mbit_BOTTOM 0x88f488f4
/***************************************************************************************************/
/*
* The data line mapping on LART is as follows:
*
* U2 CPU | U3 CPU
* -------------------
* 0 20 | 0 12
* 1 22 | 1 14
* 2 19 | 2 11
* 3 17 | 3 9
* 4 24 | 4 0
* 5 26 | 5 2
* 6 31 | 6 7
* 7 29 | 7 5
* 8 21 | 8 13
* 9 23 | 9 15
* 10 18 | 10 10
* 11 16 | 11 8
* 12 25 | 12 1
* 13 27 | 13 3
* 14 30 | 14 6
* 15 28 | 15 4
*/
/* Mangle data (x) */
#define DATA_TO_FLASH(x) \
( \
(((x) & 0x08009000) >> 11) + \
(((x) & 0x00002000) >> 10) + \
(((x) & 0x04004000) >> 8) + \
(((x) & 0x00000010) >> 4) + \
(((x) & 0x91000820) >> 3) + \
(((x) & 0x22080080) >> 2) + \
((x) & 0x40000400) + \
(((x) & 0x00040040) << 1) + \
(((x) & 0x00110000) << 4) + \
(((x) & 0x00220100) << 5) + \
(((x) & 0x00800208) << 6) + \
(((x) & 0x00400004) << 9) + \
(((x) & 0x00000001) << 12) + \
(((x) & 0x00000002) << 13) \
)
/* Unmangle data (x) */
#define FLASH_TO_DATA(x) \
( \
(((x) & 0x00010012) << 11) + \
(((x) & 0x00000008) << 10) + \
(((x) & 0x00040040) << 8) + \
(((x) & 0x00000001) << 4) + \
(((x) & 0x12200104) << 3) + \
(((x) & 0x08820020) << 2) + \
((x) & 0x40000400) + \
(((x) & 0x00080080) >> 1) + \
(((x) & 0x01100000) >> 4) + \
(((x) & 0x04402000) >> 5) + \
(((x) & 0x20008200) >> 6) + \
(((x) & 0x80000800) >> 9) + \
(((x) & 0x00001000) >> 12) + \
(((x) & 0x00004000) >> 13) \
)
/*
* The address line mapping on LART is as follows:
*
* U3 CPU | U2 CPU
* -------------------
* 0 2 | 0 2
* 1 3 | 1 3
* 2 9 | 2 9
* 3 13 | 3 8
* 4 8 | 4 7
* 5 12 | 5 6
* 6 11 | 6 5
* 7 10 | 7 4
* 8 4 | 8 10
* 9 5 | 9 11
* 10 6 | 10 12
* 11 7 | 11 13
*
* BOOT BLOCK BOUNDARY
*
* 12 15 | 12 15
* 13 14 | 13 14
* 14 16 | 14 16
*
* MAIN BLOCK BOUNDARY
*
* 15 17 | 15 18
* 16 18 | 16 17
* 17 20 | 17 20
* 18 19 | 18 19
* 19 21 | 19 21
*
* As we can see from above, the addresses aren't mangled across
* block boundaries, so we don't need to worry about address
* translations except for sending/reading commands during
* initialization
*/
/* Mangle address (x) on chip U2 */
#define ADDR_TO_FLASH_U2(x) \
( \
(((x) & 0x00000f00) >> 4) + \
(((x) & 0x00042000) << 1) + \
(((x) & 0x0009c003) << 2) + \
(((x) & 0x00021080) << 3) + \
(((x) & 0x00000010) << 4) + \
(((x) & 0x00000040) << 5) + \
(((x) & 0x00000024) << 7) + \
(((x) & 0x00000008) << 10) \
)
/* Unmangle address (x) on chip U2 */
#define FLASH_U2_TO_ADDR(x) \
( \
(((x) << 4) & 0x00000f00) + \
(((x) >> 1) & 0x00042000) + \
(((x) >> 2) & 0x0009c003) + \
(((x) >> 3) & 0x00021080) + \
(((x) >> 4) & 0x00000010) + \
(((x) >> 5) & 0x00000040) + \
(((x) >> 7) & 0x00000024) + \
(((x) >> 10) & 0x00000008) \
)
/* Mangle address (x) on chip U3 */
#define ADDR_TO_FLASH_U3(x) \
( \
(((x) & 0x00000080) >> 3) + \
(((x) & 0x00000040) >> 1) + \
(((x) & 0x00052020) << 1) + \
(((x) & 0x00084f03) << 2) + \
(((x) & 0x00029010) << 3) + \
(((x) & 0x00000008) << 5) + \
(((x) & 0x00000004) << 7) \
)
/* Unmangle address (x) on chip U3 */
#define FLASH_U3_TO_ADDR(x) \
( \
(((x) << 3) & 0x00000080) + \
(((x) << 1) & 0x00000040) + \
(((x) >> 1) & 0x00052020) + \
(((x) >> 2) & 0x00084f03) + \
(((x) >> 3) & 0x00029010) + \
(((x) >> 5) & 0x00000008) + \
(((x) >> 7) & 0x00000004) \
)
/***************************************************************************************************/
static __u8 read8 (__u32 offset)
{
volatile __u8 *data = (__u8 *) (FLASH_OFFSET + offset);
#ifdef LART_DEBUG
printk (KERN_DEBUG "%s(): 0x%.8x -> 0x%.2x\n", __func__, offset, *data);
#endif
return (*data);
}
static __u32 read32 (__u32 offset)
{
volatile __u32 *data = (__u32 *) (FLASH_OFFSET + offset);
#ifdef LART_DEBUG
printk (KERN_DEBUG "%s(): 0x%.8x -> 0x%.8x\n", __func__, offset, *data);
#endif
return (*data);
}
static void write32 (__u32 x,__u32 offset)
{
volatile __u32 *data = (__u32 *) (FLASH_OFFSET + offset);
*data = x;
#ifdef LART_DEBUG
printk (KERN_DEBUG "%s(): 0x%.8x <- 0x%.8x\n", __func__, offset, *data);
#endif
}
/***************************************************************************************************/
/*
* Probe for 16mbit flash memory on a LART board without doing
* too much damage. Since we need to write 1 dword to memory,
* we're f**cked if this happens to be DRAM since we can't
* restore the memory (otherwise we might exit Read Array mode).
*
* Returns 1 if we found 16mbit flash memory on LART, 0 otherwise.
*/
static int flash_probe (void)
{
__u32 manufacturer,devtype;
/* setup "Read Identifier Codes" mode */
write32 (DATA_TO_FLASH (READ_ID_CODES),0x00000000);
/* probe U2. U2/U3 returns the same data since the first 3
* address lines is mangled in the same way */
manufacturer = FLASH_TO_DATA (read32 (ADDR_TO_FLASH_U2 (0x00000000)));
devtype = FLASH_TO_DATA (read32 (ADDR_TO_FLASH_U2 (0x00000001)));
/* put the flash back into command mode */
write32 (DATA_TO_FLASH (READ_ARRAY),0x00000000);
return (manufacturer == FLASH_MANUFACTURER && (devtype == FLASH_DEVICE_16mbit_TOP || devtype == FLASH_DEVICE_16mbit_BOTTOM));
}
/*
* Erase one block of flash memory at offset ``offset'' which is any
* address within the block which should be erased.
*
* Returns 1 if successful, 0 otherwise.
*/
static inline int erase_block (__u32 offset)
{
__u32 status;
#ifdef LART_DEBUG
printk (KERN_DEBUG "%s(): 0x%.8x\n", __func__, offset);
#endif
/* erase and confirm */
write32 (DATA_TO_FLASH (ERASE_SETUP),offset);
write32 (DATA_TO_FLASH (ERASE_CONFIRM),offset);
/* wait for block erase to finish */
do
{
write32 (DATA_TO_FLASH (STATUS_READ),offset);
status = FLASH_TO_DATA (read32 (offset));
}
while ((~status & STATUS_BUSY) != 0);
/* put the flash back into command mode */
write32 (DATA_TO_FLASH (READ_ARRAY),offset);
/* was the erase successful? */
if ((status & STATUS_ERASE_ERR))
{
printk (KERN_WARNING "%s: erase error at address 0x%.8x.\n",module_name,offset);
return (0);
}
return (1);
}
static int flash_erase (struct mtd_info *mtd,struct erase_info *instr)
{
__u32 addr,len;
int i,first;
#ifdef LART_DEBUG
printk (KERN_DEBUG "%s(addr = 0x%.8x, len = %d)\n", __func__, instr->addr, instr->len);
#endif
/*
* check that both start and end of the requested erase are
* aligned with the erasesize at the appropriate addresses.
*
* skip all erase regions which are ended before the start of
* the requested erase. Actually, to save on the calculations,
* we skip to the first erase region which starts after the
* start of the requested erase, and then go back one.
*/
for (i = 0; i < mtd->numeraseregions && instr->addr >= mtd->eraseregions[i].offset; i++) ;
i--;
/*
* ok, now i is pointing at the erase region in which this
* erase request starts. Check the start of the requested
* erase range is aligned with the erase size which is in
* effect here.
*/
if (i < 0 || (instr->addr & (mtd->eraseregions[i].erasesize - 1)))
return -EINVAL;
/* Remember the erase region we start on */
first = i;
/*
* next, check that the end of the requested erase is aligned
* with the erase region at that address.
*
* as before, drop back one to point at the region in which
* the address actually falls
*/
for (; i < mtd->numeraseregions && instr->addr + instr->len >= mtd->eraseregions[i].offset; i++) ;
i--;
/* is the end aligned on a block boundary? */
if (i < 0 || ((instr->addr + instr->len) & (mtd->eraseregions[i].erasesize - 1)))
return -EINVAL;
addr = instr->addr;
len = instr->len;
i = first;
/* now erase those blocks */
while (len)
{
if (!erase_block (addr))
{
instr->state = MTD_ERASE_FAILED;
return (-EIO);
}
addr += mtd->eraseregions[i].erasesize;
len -= mtd->eraseregions[i].erasesize;
if (addr == mtd->eraseregions[i].offset + (mtd->eraseregions[i].erasesize * mtd->eraseregions[i].numblocks)) i++;
}
instr->state = MTD_ERASE_DONE;
mtd_erase_callback(instr);
return (0);
}
static int flash_read (struct mtd_info *mtd,loff_t from,size_t len,size_t *retlen,u_char *buf)
{
#ifdef LART_DEBUG
printk (KERN_DEBUG "%s(from = 0x%.8x, len = %d)\n", __func__, (__u32)from, len);
#endif
/* we always read len bytes */
*retlen = len;
/* first, we read bytes until we reach a dword boundary */
if (from & (BUSWIDTH - 1))
{
int gap = BUSWIDTH - (from & (BUSWIDTH - 1));
while (len && gap--) *buf++ = read8 (from++), len--;
}
/* now we read dwords until we reach a non-dword boundary */
while (len >= BUSWIDTH)
{
*((__u32 *) buf) = read32 (from);
buf += BUSWIDTH;
from += BUSWIDTH;
len -= BUSWIDTH;
}
/* top up the last unaligned bytes */
if (len & (BUSWIDTH - 1))
while (len--) *buf++ = read8 (from++);
return (0);
}
/*
* Write one dword ``x'' to flash memory at offset ``offset''. ``offset''
* must be 32 bits, i.e. it must be on a dword boundary.
*
* Returns 1 if successful, 0 otherwise.
*/
static inline int write_dword (__u32 offset,__u32 x)
{
__u32 status;
#ifdef LART_DEBUG
printk (KERN_DEBUG "%s(): 0x%.8x <- 0x%.8x\n", __func__, offset, x);
#endif
/* setup writing */
write32 (DATA_TO_FLASH (PGM_SETUP),offset);
/* write the data */
write32 (x,offset);
/* wait for the write to finish */
do
{
write32 (DATA_TO_FLASH (STATUS_READ),offset);
status = FLASH_TO_DATA (read32 (offset));
}
while ((~status & STATUS_BUSY) != 0);
/* put the flash back into command mode */
write32 (DATA_TO_FLASH (READ_ARRAY),offset);
/* was the write successful? */
if ((status & STATUS_PGM_ERR) || read32 (offset) != x)
{
printk (KERN_WARNING "%s: write error at address 0x%.8x.\n",module_name,offset);
return (0);
}
return (1);
}
static int flash_write (struct mtd_info *mtd,loff_t to,size_t len,size_t *retlen,const u_char *buf)
{
__u8 tmp[4];
int i,n;
#ifdef LART_DEBUG
printk (KERN_DEBUG "%s(to = 0x%.8x, len = %d)\n", __func__, (__u32)to, len);
#endif
/* sanity checks */
if (!len) return (0);
/* first, we write a 0xFF.... padded byte until we reach a dword boundary */
if (to & (BUSWIDTH - 1))
{
__u32 aligned = to & ~(BUSWIDTH - 1);
int gap = to - aligned;
i = n = 0;
while (gap--) tmp[i++] = 0xFF;
while (len && i < BUSWIDTH) tmp[i++] = buf[n++], len--;
while (i < BUSWIDTH) tmp[i++] = 0xFF;
if (!write_dword (aligned,*((__u32 *) tmp))) return (-EIO);
to += n;
buf += n;
*retlen += n;
}
/* now we write dwords until we reach a non-dword boundary */
while (len >= BUSWIDTH)
{
if (!write_dword (to,*((__u32 *) buf))) return (-EIO);
to += BUSWIDTH;
buf += BUSWIDTH;
*retlen += BUSWIDTH;
len -= BUSWIDTH;
}
/* top up the last unaligned bytes, padded with 0xFF.... */
if (len & (BUSWIDTH - 1))
{
i = n = 0;
while (len--) tmp[i++] = buf[n++];
while (i < BUSWIDTH) tmp[i++] = 0xFF;
if (!write_dword (to,*((__u32 *) tmp))) return (-EIO);
*retlen += n;
}
return (0);
}
/***************************************************************************************************/
static struct mtd_info mtd;
static struct mtd_erase_region_info erase_regions[] = {
/* parameter blocks */
{
.offset = 0x00000000,
.erasesize = FLASH_BLOCKSIZE_PARAM,
.numblocks = FLASH_NUMBLOCKS_16m_PARAM,
},
/* main blocks */
{
.offset = FLASH_BLOCKSIZE_PARAM * FLASH_NUMBLOCKS_16m_PARAM,
.erasesize = FLASH_BLOCKSIZE_MAIN,
.numblocks = FLASH_NUMBLOCKS_16m_MAIN,
}
};
static struct mtd_partition lart_partitions[] = {
/* blob */
{
.name = "blob",
.offset = BLOB_START,
.size = BLOB_LEN,
},
/* kernel */
{
.name = "kernel",
.offset = KERNEL_START, /* MTDPART_OFS_APPEND */
.size = KERNEL_LEN,
},
/* initial ramdisk / file system */
{
.name = "file system",
.offset = INITRD_START, /* MTDPART_OFS_APPEND */
.size = INITRD_LEN, /* MTDPART_SIZ_FULL */
}
};
#define NUM_PARTITIONS ARRAY_SIZE(lart_partitions)
static int __init lart_flash_init (void)
{
int result;
memset (&mtd,0,sizeof (mtd));
printk ("MTD driver for LART. Written by Abraham vd Merwe <abraham@2d3d.co.za>\n");
printk ("%s: Probing for 28F160x3 flash on LART...\n",module_name);
if (!flash_probe ())
{
printk (KERN_WARNING "%s: Found no LART compatible flash device\n",module_name);
return (-ENXIO);
}
printk ("%s: This looks like a LART board to me.\n",module_name);
mtd.name = module_name;
mtd.type = MTD_NORFLASH;
mtd.writesize = 1;
mtd.writebufsize = 4;
mtd.flags = MTD_CAP_NORFLASH;
mtd.size = FLASH_BLOCKSIZE_PARAM * FLASH_NUMBLOCKS_16m_PARAM + FLASH_BLOCKSIZE_MAIN * FLASH_NUMBLOCKS_16m_MAIN;
mtd.erasesize = FLASH_BLOCKSIZE_MAIN;
mtd.numeraseregions = ARRAY_SIZE(erase_regions);
mtd.eraseregions = erase_regions;
mtd._erase = flash_erase;
mtd._read = flash_read;
mtd._write = flash_write;
mtd.owner = THIS_MODULE;
#ifdef LART_DEBUG
printk (KERN_DEBUG
"mtd.name = %s\n"
"mtd.size = 0x%.8x (%uM)\n"
"mtd.erasesize = 0x%.8x (%uK)\n"
"mtd.numeraseregions = %d\n",
mtd.name,
mtd.size,mtd.size / (1024*1024),
mtd.erasesize,mtd.erasesize / 1024,
mtd.numeraseregions);
if (mtd.numeraseregions)
for (result = 0; result < mtd.numeraseregions; result++)
printk (KERN_DEBUG
"\n\n"
"mtd.eraseregions[%d].offset = 0x%.8x\n"
"mtd.eraseregions[%d].erasesize = 0x%.8x (%uK)\n"
"mtd.eraseregions[%d].numblocks = %d\n",
result,mtd.eraseregions[result].offset,
result,mtd.eraseregions[result].erasesize,mtd.eraseregions[result].erasesize / 1024,
result,mtd.eraseregions[result].numblocks);
printk ("\npartitions = %d\n", ARRAY_SIZE(lart_partitions));
for (result = 0; result < ARRAY_SIZE(lart_partitions); result++)
printk (KERN_DEBUG
"\n\n"
"lart_partitions[%d].name = %s\n"
"lart_partitions[%d].offset = 0x%.8x\n"
"lart_partitions[%d].size = 0x%.8x (%uK)\n",
result,lart_partitions[result].name,
result,lart_partitions[result].offset,
result,lart_partitions[result].size,lart_partitions[result].size / 1024);
#endif
result = mtd_device_register(&mtd, lart_partitions,
ARRAY_SIZE(lart_partitions));
return (result);
}
static void __exit lart_flash_exit (void)
{
mtd_device_unregister(&mtd);
}
module_init (lart_flash_init);
module_exit (lart_flash_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Abraham vd Merwe <abraham@2d3d.co.za>");
MODULE_DESCRIPTION("MTD driver for Intel 28F160F3 on LART board");