/*
* Physical mapping layer for MTD using the Axis partitiontable format
*
* Copyright (c) 2001, 2002 Axis Communications AB
*
* This file is under the GPL.
*
* First partition is always sector 0 regardless of if we find a partitiontable
* or not. In the start of the next sector, there can be a partitiontable that
* tells us what other partitions to define. If there isn't, we use a default
* partition split defined below.
*
* $Log: axisflashmap.c,v $
* Revision 1.11 2004/11/15 10:27:14 starvik
* Corrected typo (Thanks to Milton Miller <miltonm@bga.com>).
*
* Revision 1.10 2004/08/16 12:37:22 starvik
* Merge of Linux 2.6.8
*
* Revision 1.8 2004/05/14 07:58:03 starvik
* Merge of changes from 2.4
*
* Revision 1.6 2003/07/04 08:27:37 starvik
* Merge of Linux 2.5.74
*
* Revision 1.5 2002/12/11 13:13:57 starvik
* Added arch/ to v10 specific includes
* Added fix from Linux 2.4 in serial.c (flush_to_flip_buffer)
*
* Revision 1.4 2002/11/20 11:56:10 starvik
* Merge of Linux 2.5.48
*
* Revision 1.3 2002/11/13 14:54:13 starvik
* Copied from linux 2.4
*
* Revision 1.28 2002/10/01 08:08:43 jonashg
* The first partition ends at the start of the partition table.
*
* Revision 1.27 2002/08/21 09:23:13 jonashg
* Speling.
*
* Revision 1.26 2002/08/21 08:35:20 jonashg
* Cosmetic change to printouts.
*
* Revision 1.25 2002/08/21 08:15:42 jonashg
* Made it compile even without CONFIG_MTD_CONCAT defined.
*
* Revision 1.24 2002/08/20 13:12:35 jonashg
* * New approach to probing. Probe cse0 and cse1 separately and (mtd)concat
* the results.
* * Removed compile time tests concerning how the mtdram driver has been
* configured. The user will know about the misconfiguration at runtime
* instead. (The old approach made it impossible to use mtdram for anything
* else than RAM boot).
*
* Revision 1.23 2002/05/13 12:12:28 johana
* Allow compile without CONFIG_MTD_MTDRAM but warn at compiletime and
* be informative at runtime.
*
* Revision 1.22 2002/05/13 10:24:44 johana
* Added #if checks on MTDRAM CONFIG
*
* Revision 1.21 2002/05/06 16:05:20 johana
* Removed debug printout.
*
* Revision 1.20 2002/05/06 16:03:00 johana
* No more cramfs as root hack in generic code.
* It's handled by axisflashmap using mtdram.
*
* Revision 1.19 2002/03/15 17:10:28 bjornw
* Changed comment about cached access since we changed this before
*
* Revision 1.18 2002/03/05 17:06:15 jonashg
* Try amd_flash probe before cfi_probe since amd_flash driver can handle two
* (or more) flash chips of different model and the cfi driver cannot.
*
* Revision 1.17 2001/11/12 19:42:38 pkj
* Fixed compiler warnings.
*
* Revision 1.16 2001/11/08 11:18:58 jonashg
* Always read from uncached address to avoid problems with flushing
* cachelines after write and MTD-erase. No performance loss have been
* seen yet.
*
* Revision 1.15 2001/10/19 12:41:04 jonashg
* Name of probe has changed in MTD.
*
* Revision 1.14 2001/09/21 07:14:10 jonashg
* Made root filesystem (cramfs) use mtdblock driver when booting from flash.
*
* Revision 1.13 2001/08/15 13:57:35 jonashg
* Entire MTD updated to the linux 2.4.7 version.
*
* Revision 1.12 2001/06/11 09:50:30 jonashg
* Oops, 2MB is 0x200000 bytes.
*
* Revision 1.11 2001/06/08 11:39:44 jonashg
* Changed sizes and offsets in axis_default_partitions to use
* CONFIG_ETRAX_PTABLE_SECTOR.
*
* Revision 1.10 2001/05/29 09:42:03 jonashg
* Use macro for end marker length instead of sizeof.
*
* Revision 1.9 2001/05/29 08:52:52 jonashg
* Gave names to the magic fours (size of the ptable end marker).
*
* Revision 1.8 2001/05/28 15:36:20 jonashg
* * Removed old comment about ptable location in flash (it's a CONFIG_ option).
* * Variable ptable was initialized twice to the same value.
*
* Revision 1.7 2001/04/05 13:41:46 markusl
* Updated according to review remarks
*
* Revision 1.6 2001/03/07 09:21:21 bjornw
* No need to waste .data
*
* Revision 1.5 2001/03/06 16:27:01 jonashg
* Probe the entire flash area for flash devices.
*
* Revision 1.4 2001/02/23 12:47:15 bjornw
* Uncached flash in LOW_MAP moved from 0xe to 0x8
*
* Revision 1.3 2001/02/16 12:11:45 jonashg
* MTD driver amd_flash is now included in MTD CVS repository.
* (It's now in drivers/mtd).
*
* Revision 1.2 2001/02/09 11:12:22 jonashg
* Support for AMD compatible non-CFI flash chips.
* Only tested with Toshiba TC58FVT160 so far.
*
* Revision 1.1 2001/01/12 17:01:18 bjornw
* * Added axisflashmap.c, a physical mapping for MTD that reads and understands
* Axis partition-table format.
*
*
*/
#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/mtd/concat.h>
#include <linux/mtd/map.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/mtdram.h>
#include <linux/mtd/partitions.h>
#include <asm/axisflashmap.h>
#include <asm/mmu.h>
#include <asm/arch/sv_addr_ag.h>
#ifdef CONFIG_CRIS_LOW_MAP
#define FLASH_UNCACHED_ADDR KSEG_8
#define FLASH_CACHED_ADDR KSEG_5
#else
#define FLASH_UNCACHED_ADDR KSEG_E
#define FLASH_CACHED_ADDR KSEG_F
#endif
#if CONFIG_ETRAX_FLASH_BUSWIDTH==1
#define flash_data __u8
#elif CONFIG_ETRAX_FLASH_BUSWIDTH==2
#define flash_data __u16
#elif CONFIG_ETRAX_FLASH_BUSWIDTH==4
#define flash_data __u32
#endif
/* From head.S */
extern unsigned long romfs_start, romfs_length, romfs_in_flash;
/* The master mtd for the entire flash. */
struct mtd_info* axisflash_mtd = NULL;
/* Map driver functions. */
static map_word flash_read(struct map_info *map, unsigned long ofs)
{
map_word tmp;
tmp.x[0] = *(flash_data *)(map->map_priv_1 + ofs);
return tmp;
}
static void flash_copy_from(struct map_info *map, void *to,
unsigned long from, ssize_t len)
{
memcpy(to, (void *)(map->map_priv_1 + from), len);
}
static void flash_write(struct map_info *map, map_word d, unsigned long adr)
{
*(flash_data *)(map->map_priv_1 + adr) = (flash_data)d.x[0];
}
/*
* The map for chip select e0.
*
* We run into tricky coherence situations if we mix cached with uncached
* accesses to we only use the uncached version here.
*
* The size field is the total size where the flash chips may be mapped on the
* chip select. MTD probes should find all devices there and it does not matter
* if there are unmapped gaps or aliases (mirrors of flash devices). The MTD
* probes will ignore them.
*
* The start address in map_priv_1 is in virtual memory so we cannot use
* MEM_CSE0_START but must rely on that FLASH_UNCACHED_ADDR is the start
* address of cse0.
*/
static struct map_info map_cse0 = {
.name = "cse0",
.size = MEM_CSE0_SIZE,
.bankwidth = CONFIG_ETRAX_FLASH_BUSWIDTH,
.read = flash_read,
.copy_from = flash_copy_from,
.write = flash_write,
.map_priv_1 = FLASH_UNCACHED_ADDR
};
/*
* The map for chip select e1.
*
* If there was a gap between cse0 and cse1, map_priv_1 would get the wrong
* address, but there isn't.
*/
static struct map_info map_cse1 = {
.name = "cse1",
.size = MEM_CSE1_SIZE,
.bankwidth = CONFIG_ETRAX_FLASH_BUSWIDTH,
.read = flash_read,
.copy_from = flash_copy_from,
.write = flash_write,
.map_priv_1 = FLASH_UNCACHED_ADDR + MEM_CSE0_SIZE
};
/* If no partition-table was found, we use this default-set. */
#define MAX_PARTITIONS 7
#define NUM_DEFAULT_PARTITIONS 3
/*
* Default flash size is 2MB. CONFIG_ETRAX_PTABLE_SECTOR is most likely the
* size of one flash block and "filesystem"-partition needs 5 blocks to be able
* to use JFFS.
*/
static struct mtd_partition axis_default_partitions[NUM_DEFAULT_PARTITIONS] = {
{
.name = "boot firmware",
.size = CONFIG_ETRAX_PTABLE_SECTOR,
.offset = 0
},
{
.name = "kernel",
.size = 0x200000 - (6 * CONFIG_ETRAX_PTABLE_SECTOR),
.offset = CONFIG_ETRAX_PTABLE_SECTOR
},
{
.name = "filesystem",
.size = 5 * CONFIG_ETRAX_PTABLE_SECTOR,
.offset = 0x200000 - (5 * CONFIG_ETRAX_PTABLE_SECTOR)
}
};
/* Initialize the ones normally used. */
static struct mtd_partition axis_partitions[MAX_PARTITIONS] = {
{
.name = "part0",
.size = CONFIG_ETRAX_PTABLE_SECTOR,
.offset = 0
},
{
.name = "part1",
.size = 0,
.offset = 0
},
{
.name = "part2",
.size = 0,
.offset = 0
},
{
.name = "part3",
.size = 0,
.offset = 0
},
{
.name = "part4",
.size = 0,
.offset = 0
},
{
.name = "part5",
.size = 0,
.offset = 0
},
{
.name = "part6",
.size = 0,
.offset = 0
},
};
/*
* Probe a chip select for AMD-compatible (JEDEC) or CFI-compatible flash
* chips in that order (because the amd_flash-driver is faster).
*/
static struct mtd_info *probe_cs(struct map_info *map_cs)
{
struct mtd_info *mtd_cs = NULL;
printk(KERN_INFO
"%s: Probing a 0x%08lx bytes large window at 0x%08lx.\n",
map_cs->name, map_cs->size, map_cs->map_priv_1);
#ifdef CONFIG_MTD_CFI
mtd_cs = do_map_probe("cfi_probe", map_cs);
#endif
#ifdef CONFIG_MTD_JEDECPROBE
if (!mtd_cs) {
mtd_cs = do_map_probe("jedec_probe", map_cs);
}
#endif
return mtd_cs;
}
/*
* Probe each chip select individually for flash chips. If there are chips on
* both cse0 and cse1, the mtd_info structs will be concatenated to one struct
* so that MTD partitions can cross chip boundries.
*
* The only known restriction to how you can mount your chips is that each
* chip select must hold similar flash chips. But you need external hardware
* to do that anyway and you can put totally different chips on cse0 and cse1
* so it isn't really much of a restriction.
*/
static struct mtd_info *flash_probe(void)
{
struct mtd_info *mtd_cse0;
struct mtd_info *mtd_cse1;
struct mtd_info *mtd_cse;
mtd_cse0 = probe_cs(&map_cse0);
mtd_cse1 = probe_cs(&map_cse1);
if (!mtd_cse0 && !mtd_cse1) {
/* No chip found. */
return NULL;
}
if (mtd_cse0 && mtd_cse1) {
#ifdef CONFIG_MTD_CONCAT
struct mtd_info *mtds[] = { mtd_cse0, mtd_cse1 };
/* Since the concatenation layer adds a small overhead we
* could try to figure out if the chips in cse0 and cse1 are
* identical and reprobe the whole cse0+cse1 window. But since
* flash chips are slow, the overhead is relatively small.
* So we use the MTD concatenation layer instead of further
* complicating the probing procedure.
*/
mtd_cse = mtd_concat_create(mtds, ARRAY_SIZE(mtds),
"cse0+cse1");
#else
printk(KERN_ERR "%s and %s: Cannot concatenate due to kernel "
"(mis)configuration!\n", map_cse0.name, map_cse1.name);
mtd_cse = NULL;
#endif
if (!mtd_cse) {
printk(KERN_ERR "%s and %s: Concatenation failed!\n",
map_cse0.name, map_cse1.name);
/* The best we can do now is to only use what we found
* at cse0.
*/
mtd_cse = mtd_cse0;
map_destroy(mtd_cse1);
}
} else {
mtd_cse = mtd_cse0? mtd_cse0 : mtd_cse1;
}
return mtd_cse;
}
/*
* Probe the flash chip(s) and, if it succeeds, read the partition-table
* and register the partitions with MTD.
*/
static int __init init_axis_flash(void)
{
struct mtd_info *mymtd;
int err = 0;
int pidx = 0;
struct partitiontable_head *ptable_head = NULL;
struct partitiontable_entry *ptable;
int use_default_ptable = 1; /* Until proven otherwise. */
const char *pmsg = " /dev/flash%d at 0x%08x, size 0x%08x\n";
if (!(mymtd = flash_probe())) {
/* There's no reason to use this module if no flash chip can
* be identified. Make sure that's understood.
*/
printk(KERN_INFO "axisflashmap: Found no flash chip.\n");
} else {
printk(KERN_INFO "%s: 0x%08x bytes of flash memory.\n",
mymtd->name, mymtd->size);
axisflash_mtd = mymtd;
}
if (mymtd) {
mymtd->owner = THIS_MODULE;
ptable_head = (struct partitiontable_head *)(FLASH_CACHED_ADDR +
CONFIG_ETRAX_PTABLE_SECTOR +
PARTITION_TABLE_OFFSET);
}
pidx++; /* First partition is always set to the default. */
if (ptable_head && (ptable_head->magic == PARTITION_TABLE_MAGIC)
&& (ptable_head->size <
(MAX_PARTITIONS * sizeof(struct partitiontable_entry) +
PARTITIONTABLE_END_MARKER_SIZE))
&& (*(unsigned long*)((void*)ptable_head + sizeof(*ptable_head) +
ptable_head->size -
PARTITIONTABLE_END_MARKER_SIZE)
== PARTITIONTABLE_END_MARKER)) {
/* Looks like a start, sane length and end of a
* partition table, lets check csum etc.
*/
int ptable_ok = 0;
struct partitiontable_entry *max_addr =
(struct partitiontable_entry *)
((unsigned long)ptable_head + sizeof(*ptable_head) +
ptable_head->size);
unsigned long offset = CONFIG_ETRAX_PTABLE_SECTOR;
unsigned char *p;
unsigned long csum = 0;
ptable = (struct partitiontable_entry *)
((unsigned long)ptable_head + sizeof(*ptable_head));
/* Lets be PARANOID, and check the checksum. */
p = (unsigned char*) ptable;
while (p <= (unsigned char*)max_addr) {
csum += *p++;
csum += *p++;
csum += *p++;
csum += *p++;
}
ptable_ok = (csum == ptable_head->checksum);
/* Read the entries and use/show the info. */
printk(KERN_INFO " Found a%s partition table at 0x%p-0x%p.\n",
(ptable_ok ? " valid" : "n invalid"), ptable_head,
max_addr);
/* We have found a working bootblock. Now read the
* partition table. Scan the table. It ends when
* there is 0xffffffff, that is, empty flash.
*/
while (ptable_ok
&& ptable->offset != 0xffffffff
&& ptable < max_addr
&& pidx < MAX_PARTITIONS) {
axis_partitions[pidx].offset = offset + ptable->offset;
axis_partitions[pidx].size = ptable->size;
printk(pmsg, pidx, axis_partitions[pidx].offset,
axis_partitions[pidx].size);
pidx++;
ptable++;
}
use_default_ptable = !ptable_ok;
}
if (romfs_in_flash) {
/* Add an overlapping device for the root partition (romfs). */
axis_partitions[pidx].name = "romfs";
axis_partitions[pidx].size = romfs_length;
axis_partitions[pidx].offset = romfs_start - FLASH_CACHED_ADDR;
axis_partitions[pidx].mask_flags |= MTD_WRITEABLE;
printk(KERN_INFO
" Adding readonly flash partition for romfs image:\n");
printk(pmsg, pidx, axis_partitions[pidx].offset,
axis_partitions[pidx].size);
pidx++;
}
if (mymtd) {
if (use_default_ptable) {
printk(KERN_INFO " Using default partition table.\n");
err = add_mtd_partitions(mymtd, axis_default_partitions,
NUM_DEFAULT_PARTITIONS);
} else {
err = add_mtd_partitions(mymtd, axis_partitions, pidx);
}
if (err) {
panic("axisflashmap could not add MTD partitions!\n");
}
}
if (!romfs_in_flash) {
/* Create an RAM device for the root partition (romfs). */
#if !defined(CONFIG_MTD_MTDRAM) || (CONFIG_MTDRAM_TOTAL_SIZE != 0) || (CONFIG_MTDRAM_ABS_POS != 0)
/* No use trying to boot this kernel from RAM. Panic! */
printk(KERN_EMERG "axisflashmap: Cannot create an MTD RAM "
"device due to kernel (mis)configuration!\n");
panic("This kernel cannot boot from RAM!\n");
#else
struct mtd_info *mtd_ram;
mtd_ram = kmalloc(sizeof(struct mtd_info),
GFP_KERNEL);
if (!mtd_ram) {
panic("axisflashmap couldn't allocate memory for "
"mtd_info!\n");
}
printk(KERN_INFO " Adding RAM partition for romfs image:\n");
printk(pmsg, pidx, romfs_start, romfs_length);
err = mtdram_init_device(mtd_ram, (void*)romfs_start,
romfs_length, "romfs");
if (err) {
panic("axisflashmap could not initialize MTD RAM "
"device!\n");
}
#endif
}
return err;
}
/* This adds the above to the kernels init-call chain. */
module_init(init_axis_flash);
EXPORT_SYMBOL(axisflash_mtd);
