lart.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 PART_BLOB_START 0x00000000
#define PART_BLOB_LEN (NUM_BLOB_BLOCKS * FLASH_BLOCKSIZE_PARAM)
/* kernel */
#define NUM_KERNEL_BLOCKS 7
#define PART_KERNEL_START (PART_BLOB_START + PART_BLOB_LEN)
#define PART_KERNEL_LEN (NUM_KERNEL_BLOCKS * FLASH_BLOCKSIZE_MAIN)
/* initial ramdisk */
#define NUM_INITRD_BLOCKS 24
#define PART_INITRD_START (PART_KERNEL_START + PART_KERNEL_LEN)
#define PART_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))
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++;
}
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 const struct mtd_partition lart_partitions[] = {
/* blob */
{
.name = "blob",
.offset = PART_BLOB_START,
.size = PART_BLOB_LEN,
},
/* kernel */
{
.name = "kernel",
.offset = PART_KERNEL_START, /* MTDPART_OFS_APPEND */
.size = PART_KERNEL_LEN,
},
/* initial ramdisk / file system */
{
.name = "file system",
.offset = PART_INITRD_START, /* MTDPART_OFS_APPEND */
.size = PART_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");