arch/cris/arch-v32/drivers/axisflashmap.c - kernel/msm-4.9 - Gitiles

 /*
  * Physical mapping layer for MTD using the Axis partitiontable format
  *
  * Copyright (c) 2001, 2002, 2003 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.
  *
  * Copy of os/lx25/arch/cris/arch-v10/drivers/axisflashmap.c 1.5
  * with minor changes.
  *
  */

 #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/arch/hwregs/config_defs.h>
 #include <asm/axisflashmap.h>
 #include <asm/mmu.h>

 #define MEM_CSE0_SIZE (0x04000000)
 #define MEM_CSE1_SIZE (0x04000000)

 #define FLASH_UNCACHED_ADDR  KSEG_E
 #define FLASH_CACHED_ADDR    KSEG_F

 #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 __u16
 #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 boundaries.
  *
  * 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.
  */
 extern struct mtd_info* __init crisv32_nand_flash_probe (void);
 static struct mtd_info *flash_probe(void)
 {
 	struct mtd_info *mtd_cse0;
 	struct mtd_info *mtd_cse1;
 	struct mtd_info *mtd_nand = NULL;
 	struct mtd_info *mtd_total;
 	struct mtd_info *mtds[3];
 	int count = 0;

 	if ((mtd_cse0 = probe_cs(&map_cse0)) != NULL)
 		mtds[count++] = mtd_cse0;
 	if ((mtd_cse1 = probe_cs(&map_cse1)) != NULL)
 		mtds[count++] = mtd_cse1;

 #ifdef CONFIG_ETRAX_NANDFLASH
 	if ((mtd_nand = crisv32_nand_flash_probe()) != NULL)
 		mtds[count++] = mtd_nand;
 #endif

 	if (!mtd_cse0 && !mtd_cse1 && !mtd_nand) {
 		/* No chip found. */
 		return NULL;
 	}

 	if (count > 1) {
 #ifdef CONFIG_MTD_CONCAT
 		/* 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_total = mtd_concat_create(mtds,
 		                              count,
 		                              "cse0+cse1+nand");
 #else
 		printk(KERN_ERR "%s and %s: Cannot concatenate due to kernel "
 		       "(mis)configuration!\n", map_cse0.name, map_cse1.name);
 		mtd_toal = NULL;
 #endif
 		if (!mtd_total) {
 			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_total = mtd_cse0;
 			map_destroy(mtd_cse1);
 		}
 	} else {
 		mtd_total = mtd_cse0? mtd_cse0 : mtd_cse1 ? mtd_cse1 : mtd_nand;

 	}

 	return mtd_total;
 }

 extern unsigned long crisv32_nand_boot;
 extern unsigned long crisv32_nand_cramfs_offset;

 /*
  * 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 = KERN_INFO "  /dev/flash%d at 0x%08x, size 0x%08x\n";
 	static char page[512];
 	size_t len;

 #ifndef CONFIG_ETRAXFS_SIM
 	mymtd = flash_probe();
 	mymtd->read(mymtd, CONFIG_ETRAX_PTABLE_SECTOR, 512, &len, page);
 	ptable_head = (struct partitiontable_head *)(page + PARTITION_TABLE_OFFSET);

 	if (!mymtd) {
 		/* 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;
 	}
 	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 + (crisv32_nand_boot ? 16384 : 0);
 			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";
 		if (crisv32_nand_boot) {
 			char* data = kmalloc(1024, GFP_KERNEL);
 			int len;
 			int offset = crisv32_nand_cramfs_offset & ~(1024-1);
 			char* tmp;

 			mymtd->read(mymtd, offset, 1024, &len, data);
 			tmp = &data[crisv32_nand_cramfs_offset % 512];
 			axis_partitions[pidx].size = *(unsigned*)(tmp + 4);
 			axis_partitions[pidx].offset = crisv32_nand_cramfs_offset;
 			kfree(data);
 		} else {
 			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");
 		}
 	}
 /* CONFIG_EXTRAXFS_SIM */
 #endif

 	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);
	/*
	* Physical mapping layer for MTD using the Axis partitiontable format
	*
	* Copyright (c) 2001, 2002, 2003 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.
	*
	* Copy of os/lx25/arch/cris/arch-v10/drivers/axisflashmap.c 1.5
	* with minor changes.
	*
	*/

	#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/arch/hwregs/config_defs.h>
	#include <asm/axisflashmap.h>
	#include <asm/mmu.h>

	#define MEM_CSE0_SIZE (0x04000000)
	#define MEM_CSE1_SIZE (0x04000000)

	#define FLASH_UNCACHED_ADDR KSEG_E
	#define FLASH_CACHED_ADDR KSEG_F

	#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 __u16
	#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 boundaries.
	*
	* 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.
	*/
	extern struct mtd_info* __init crisv32_nand_flash_probe (void);
	static struct mtd_info *flash_probe(void)
	{
	struct mtd_info *mtd_cse0;
	struct mtd_info *mtd_cse1;
	struct mtd_info *mtd_nand = NULL;
	struct mtd_info *mtd_total;
	struct mtd_info *mtds[3];
	int count = 0;

	if ((mtd_cse0 = probe_cs(&map_cse0)) != NULL)
	mtds[count++] = mtd_cse0;
	if ((mtd_cse1 = probe_cs(&map_cse1)) != NULL)
	mtds[count++] = mtd_cse1;

	#ifdef CONFIG_ETRAX_NANDFLASH
	if ((mtd_nand = crisv32_nand_flash_probe()) != NULL)
	mtds[count++] = mtd_nand;
	#endif

	if (!mtd_cse0 && !mtd_cse1 && !mtd_nand) {
	/* No chip found. */
	return NULL;
	}

	if (count > 1) {
	#ifdef CONFIG_MTD_CONCAT
	/* 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_total = mtd_concat_create(mtds,
	count,
	"cse0+cse1+nand");
	#else
	printk(KERN_ERR "%s and %s: Cannot concatenate due to kernel "
	"(mis)configuration!\n", map_cse0.name, map_cse1.name);
	mtd_toal = NULL;
	#endif
	if (!mtd_total) {
	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_total = mtd_cse0;
	map_destroy(mtd_cse1);
	}
	} else {
	mtd_total = mtd_cse0? mtd_cse0 : mtd_cse1 ? mtd_cse1 : mtd_nand;

	}

	return mtd_total;
	}

	extern unsigned long crisv32_nand_boot;
	extern unsigned long crisv32_nand_cramfs_offset;

	/*
	* 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 = KERN_INFO " /dev/flash%d at 0x%08x, size 0x%08x\n";
	static char page[512];
	size_t len;

	#ifndef CONFIG_ETRAXFS_SIM
	mymtd = flash_probe();
	mymtd->read(mymtd, CONFIG_ETRAX_PTABLE_SECTOR, 512, &len, page);
	ptable_head = (struct partitiontable_head *)(page + PARTITION_TABLE_OFFSET);

	if (!mymtd) {
	/* 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;
	}
	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 + (crisv32_nand_boot ? 16384 : 0);
	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";
	if (crisv32_nand_boot) {
	char* data = kmalloc(1024, GFP_KERNEL);
	int len;
	int offset = crisv32_nand_cramfs_offset & ~(1024-1);
	char* tmp;

	mymtd->read(mymtd, offset, 1024, &len, data);
	tmp = &data[crisv32_nand_cramfs_offset % 512];
	axis_partitions[pidx].size = (unsigned)(tmp + 4);
	axis_partitions[pidx].offset = crisv32_nand_cramfs_offset;
	kfree(data);
	} else {
	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");
	}
	}
	/* CONFIG_EXTRAXFS_SIM */
	#endif

	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);