/*
 * $Id: nora.c,v 1.12 2000/07/13 10:32:33 dwmw2 Exp $
 *
 * This is so simple I love it.
 *
 *
 * Added new flash partition schema for agenda
 * Copyright 2003 (C) Andreas Holzer
 *
 * Added noraPartWriteProc
 * Copyright 2003 (C) Paul Andreassen
 */

#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>

#include <linux/proc_fs.h>

#include <linux/mtd/mtd.h>
#include <linux/mtd/map.h>
#include <linux/mtd/partitions.h>

#define WINDOW_ADDR 0xbf000000
#define WINDOW_SIZE 0x01000000
#ifdef MTD_XIP
#define MTD_ELF_SECTION __attribute__((__section__(".xir")))
#else
#define MTD_ELF_SECTION
#endif

#define DISCO_START  0xc00000
#define DISCO_LEN    0x080000
#define DISCO_END    (DISCO_START + DISCO_LEN)

/* adjust an address for the discontinuity */
#define DISCO_ADJUST(a) ((a<DISCO_START)?a:(a+DISCO_LEN))


extern int bflag;

static struct mtd_info *mymtd;

MTD_ELF_SECTION __u8 nora_read8(struct map_info *map, unsigned long ofs)
{
  return *(__u8 *)(WINDOW_ADDR + ofs);
}

MTD_ELF_SECTION __u16 nora_read16(struct map_info *map, unsigned long ofs)
{
  return *(__u16 *)(WINDOW_ADDR + ofs);
}

MTD_ELF_SECTION __u32 nora_read32(struct map_info *map, unsigned long ofs)
{
  return *(__u32 *)(WINDOW_ADDR + ofs);
}

MTD_ELF_SECTION void nora_copy_from(struct map_info *map, void *to, unsigned long from, ssize_t len)
{
  memcpy(to, (void *)(WINDOW_ADDR + from), len);
}

MTD_ELF_SECTION void nora_write8(struct map_info *map, __u8 d, unsigned long adr)
{
  *(__u8 *)(WINDOW_ADDR + adr) = d;
}

MTD_ELF_SECTION void nora_write16(struct map_info *map, __u16 d, unsigned long adr)
{

  *(__u16 *)(WINDOW_ADDR + adr) = d;


}

MTD_ELF_SECTION void nora_write32(struct map_info *map, __u32 d, unsigned long adr)
{

  *(__u32 *)(WINDOW_ADDR + adr) = d;

}

MTD_ELF_SECTION void nora_copy_to(struct map_info *map, unsigned long to, const void *from, ssize_t len)
{
  memcpy((void *)(WINDOW_ADDR + to), from, len);
}

struct map_info nora_map = {
	name: "NORA",
	size: WINDOW_SIZE,
	buswidth: 2,
	read8: nora_read8,
	read16: nora_read16,
	read32: nora_read32,
	copy_from: nora_copy_from,
	write8: nora_write8,
	write16: nora_write16,
	write32: nora_write32,
	copy_to: nora_copy_to
};


MTD_ELF_SECTION static int nora_mtd_read (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf)
{
    //printk("nora_read(): %x\n",buf);
	return mymtd->read(mymtd, from + (unsigned long)mtd->priv, len, retlen, buf);
}


MTD_ELF_SECTION static int nora_mtd_disco_read (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf)
{

       unsigned long pos = from + (unsigned long)mtd->priv;

       if ( ((len + pos) <= DISCO_START) ||
            ((pos) >= DISCO_START)){
               return mymtd->read(mymtd, DISCO_ADJUST(pos), len, retlen, buf);
       }else{
               printk("Discontinuity boundary crossed in nora_mtd_disco_read");
               panic("Discontinuity boundary crossed in nora_mtd_disco_read");
       }
}


MTD_ELF_SECTION static int nora_mtd_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen, const u_char *buf)
{

	return mymtd->write(mymtd, to + (unsigned long)mtd->priv, len, retlen, buf);
}


MTD_ELF_SECTION static int nora_mtd_disco_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen, const u_char *buf)
{

       unsigned long pos = to + (unsigned long)mtd->priv;

       if ( ((len + pos) <= DISCO_START) ||
            ((pos) >= DISCO_START)){

               return mymtd->write(mymtd, DISCO_ADJUST(pos), len, retlen, buf);
       }else{
               printk("Discontinuity boundary crossed in nora_mtd_disco_write");
               panic("Discontinuity boundary crossed in nora_mtd_disco_write");
       }
}

MTD_ELF_SECTION static int nora_mtd_erase (struct mtd_info *mtd, struct erase_info *instr)
{
	instr->addr += (unsigned long)mtd->priv;
	return mymtd->erase(mymtd, instr);
}


MTD_ELF_SECTION static int nora_mtd_disco_erase (struct mtd_info *mtd, struct erase_info *instr)
{
       unsigned long pos = instr->addr + (unsigned long)mtd->priv;
       instr->addr = DISCO_ADJUST(pos);
       return mymtd->erase(mymtd, instr);
}

MTD_ELF_SECTION static void nora_mtd_sync (struct mtd_info *mtd)
{
	mymtd->sync(mymtd);
}

MTD_ELF_SECTION static int nora_mtd_suspend (struct mtd_info *mtd)
{
	return mymtd->suspend(mymtd);
}

MTD_ELF_SECTION static void nora_mtd_resume (struct mtd_info *mtd)
{
	mymtd->resume(mymtd);
}


static struct mtd_info nora_mtds[2] = {  /* boot, kernel, ramdisk, fs */
	{
		type: MTD_NORFLASH,
		flags: MTD_CAP_NORFLASH,
		size: 0x380000,
		erasesize: 0x20000,
		name: "Agenda 3.5MB JFFS Partition",
		module: THIS_MODULE,
		erase: nora_mtd_erase,
		read: nora_mtd_read,
		write: nora_mtd_write,
		suspend: nora_mtd_suspend,
		resume: nora_mtd_resume,
		sync: nora_mtd_sync,
		priv: (void *)0xc80000
	},
	{
		type: MTD_NORFLASH,
		flags: MTD_CAP_NORFLASH | MTD_WRITEABLE,
		size: 0xf80000,             // flash size - PMON size
		erasesize: 0x20000,
		name: "Agenda 12MB Flash",
		module: THIS_MODULE,
		erase: nora_mtd_disco_erase,   // access routine bridge the hole inside
		read: nora_mtd_disco_read,
		write: nora_mtd_disco_write,
		suspend: nora_mtd_suspend,
		resume: nora_mtd_resume,
		sync: nora_mtd_sync,
		priv: (void *)0x0
	}, 
        /* only prepared not initialized in setup */
        {
		type: MTD_NORFLASH,
		flags: MTD_CAP_NORFLASH,
		size: 0x080000,
		erasesize: 0x20000,
		name: "Pmon (very experimental)",
		module: THIS_MODULE,
		erase: nora_mtd_erase,
		read: nora_mtd_read,
		write: nora_mtd_write,
		suspend: nora_mtd_suspend,
		resume: nora_mtd_resume,
		sync: nora_mtd_sync,
		priv: (void *)0xC00000,
	}
};

/*
 * MTD 'PARTITIONING' STUFF
 */
static unsigned long nrparts = 3;

#define MTD_PNAME_MAX 30

static char np_text[][MTD_PNAME_MAX] = {
	"Kernel",
	"Root",
	"Flash",
	"",
	""
};

static struct mtd_partition nora_partitions[] = {
	{
		name:   np_text[0],
		offset: 0,
#ifdef CONFIG_XIP_ROM
		size:   0x200000
#else
		size:   0x100000
#endif
	},
   	{
		name:   np_text[1],
#ifdef CONFIG_XIP_ROM
		offset: 0x200000, 
                size:   0xA00000    // 0xC80000  
#else
                offset: 0x100000, 
		size:   0xB00000    // 0xE80000
#endif
	},
	{
		name:   np_text[2],
		offset: 0xC00000,     // dangerous stuff for PMON hole 
		size:   0x380000,     // simulates flash access via mtd[1]
	},
	{
		name:   np_text[3],
		offset: 0,
		size:   0
	},
	{
		name:   np_text[4],
		offset: 0,
		size:   0
	}
};

static inline int noraProcInfo (char *buf, int i)
{
	return sprintf(buf, "mtdblock%d: %08lx(%08lx) %08lx \"%s\" %04x\n", i+2,
		nora_partitions[i].offset,
                DISCO_ADJUST(nora_partitions[i].offset),
		nora_partitions[i].size,
		nora_partitions[i].name,
                nora_partitions[i].mask_flags);
}

static int noraPartReadProc ( char *page, char **start,
	off_t off,int count,int *eof, void *data_unused)
{
	int len = 0, l, i;
	off_t   begin = 0;

	for (i=0; i< nrparts; i++) {

		l = noraProcInfo(page + len, i);
		len += l;
		if (len+begin > off+count)
				goto done;
		if (len+begin < off) {
				begin += len;
				len = 0;
		}
	}

	*eof = 1;

done:

	if (off >= len+begin)
		return 0;
	*start = page + (begin-off);
	return ((count < begin+len-off) ? count : begin+len-off);
}

/*
output format:
mtdblock2: 00000000 00200000 "Kernel"
mtdblock3: 00200000 00700000 "Root-Cramfs"
mtdblock4: 00a00000 00200000 "Tools-Cramfs"
mtdblock5: 00900000 00100000 "Extra-Cramfs"

input format:
.*[0-9].* [0-F]* [0-F]* ".*"
*/
static int noraPartWriteProc(struct file *file, const char *buffer,
				unsigned long count, void *data)
{
	const int maxBuffer=80;
	char szBuffer[maxBuffer+1];
	int sizeBuffer, sizeName, mtdblock;
	char *pBuffer, *pName;
	u_long offset, size;

	if (!capable(CAP_SYS_ADMIN))
		return -EACCES;

	// copy string (not sure why we do this, maybe to do with highmem?)
	sizeBuffer = (count < maxBuffer) ? count : maxBuffer;
	copy_from_user(szBuffer, buffer, sizeBuffer);
	szBuffer[sizeBuffer] = '\0';
	pBuffer=szBuffer;

	// find a number
	while ((*pBuffer<'0') || (*pBuffer>'9'))
		if (++pBuffer >= (szBuffer+sizeBuffer))
			return -EINVAL;

	mtdblock=*pBuffer-'0';

	// only allowed mtdblocks be added in order upto 6
#ifdef CONFIG_CRAMFS_LINEAR
	if ((mtdblock<4) || ((mtdblock-2)>nrparts) || (mtdblock>6))
		return -ERANGE;
#else
	if ((mtdblock<3) || ((mtdblock-2)>nrparts) || (mtdblock>6))
		return -ERANGE;
#endif

	// skip until space or tab
	while ((*pBuffer!=' ') && (*pBuffer!= '\t'))
		if (++pBuffer >= (szBuffer+sizeBuffer))
			return -EINVAL;

	// skip space or tab
	while ((*pBuffer==' ') || (*pBuffer== '\t'))
		if (++pBuffer >= (szBuffer+sizeBuffer))
			return -EINVAL;

	// read offset
	offset=simple_strtoul(pBuffer, &pBuffer, 16);

	// skip space or tab
	while ((*pBuffer==' ') || (*pBuffer== '\t'))
		if (++pBuffer >= (szBuffer+sizeBuffer))
			return -EINVAL;

	// read size
	size=simple_strtoul(pBuffer, &pBuffer, 16);

	// skip space or tab
	while ((*pBuffer==' ') || (*pBuffer== '\t'))
		if (++pBuffer >= (szBuffer+sizeBuffer))
			return -EINVAL;

	// find name start
	if (*pBuffer!='\"')
		return -EINVAL;

	if (++pBuffer >= (szBuffer+sizeBuffer))
		return -EINVAL;

	pName=pBuffer;

	// find name end
	while ((*pBuffer!='\"') && (++pBuffer < (szBuffer+sizeBuffer)));

	// update partitions
	if ((mtdblock-2)>=nrparts)
		nrparts++;

	sizeName = (pBuffer-pName);
	sizeName = (sizeName >= MTD_PNAME_MAX) ? MTD_PNAME_MAX - 1: sizeName;
	strncpy(nora_partitions[mtdblock-2].name, pName, sizeName);
	nora_partitions[mtdblock-2].name[sizeName]='\0';

	nora_partitions[mtdblock-2].offset=offset;
	nora_partitions[mtdblock-2].size=((size-1)|(0x20000UL-1))+1;

	printk(KERN_NOTICE "added/updated mtdblock%d: %08lx %08lx \"%s\"\n",
		mtdblock,
		nora_partitions[mtdblock-2].offset,
		nora_partitions[mtdblock-2].size,
		nora_partitions[mtdblock-2].name);

	del_mtd_partitions(&(nora_mtds[1]));
	// skip testing because add_mtd_partitions does it
	add_mtd_partitions(&(nora_mtds[1]), nora_partitions, nrparts);

	return count;
}

#ifdef CONFIG_CRAMFS_LINEAR

void add_cramfs_linear_partition(u_long offset, u_long size)
{
	const char *name = "Root-Cramfs";
	const char *name2 = "Root-Cramfs (size a guess)";

	// assumes that linear cramfs are loaded very early in boot process
	if (nrparts == 1)
		nrparts = 2;

	offset-=WINDOW_ADDR;

	if (size != 0x10000) {
		size=((size-1)|(0x20000UL-1))+1;
		strncpy(nora_partitions[1].name, name, strlen(name)+1);
		printk(KERN_INFO "cramfsl: added linear partition mtdblock3: %08lx %08lx \"%s\"\n",
			offset, size, nora_partitions[1].name);
	} else {
		size = 0x700000;
		strncpy(nora_partitions[1].name, name2, strlen(name2)+1);
		printk(KERN_INFO "cramfsl: added linear partition mtdblock3: %08lx 00010000 \"%s\" size changed to %08lx\n",
			offset, nora_partitions[1].name, size);
	}

	nora_partitions[1].offset=offset;
	nora_partitions[1].size=size;

	del_mtd_partitions(&(nora_mtds[1]));
	add_mtd_partitions(&(nora_mtds[1]), nora_partitions, nrparts);
}

#endif

#if LINUX_VERSION_CODE < 0x20300
#ifdef MODULE
#define init_nora init_module
#define cleanup_nora cleanup_module
#endif
#endif

int __init init_nora(void)
{
	struct proc_dir_entry *procNoraPart;
	int ret;

	printk(KERN_NOTICE "nora flash device: %x at %x\n", WINDOW_SIZE, WINDOW_ADDR);

	mymtd = do_cfi_probe(&nora_map);

	if (mymtd) {
#ifdef MODULE
		mymtd->module = &__this_module;
#endif

		add_mtd_device(&nora_mtds[0]);

		add_mtd_device(&nora_mtds[1]);
		ret=add_mtd_partitions(&nora_mtds[1], nora_partitions, nrparts);

		if ((procNoraPart = create_proc_entry("noraPartitions", 0, 0))){
			procNoraPart->read_proc = noraPartReadProc;
			procNoraPart->write_proc = noraPartWriteProc;
		}

		return ret;
	}

	return -ENXIO;
}

static void __exit cleanup_nora(void)
{
	if (mymtd) {
		remove_proc_entry("noraPartitions", 0);

		del_mtd_partitions(&(nora_mtds[1]));
		del_mtd_device(&(nora_mtds[1]));

		del_mtd_device(&(nora_mtds[0]));

		map_destroy(mymtd);
	}
}

module_init(init_nora);
module_exit(cleanup_nora);

EXPORT_SYMBOL(nora_mtds);
EXPORT_SYMBOL(nora_partitions);  

#ifdef CONFIG_CRAMFS_LINEAR
EXPORT_SYMBOL(add_cramfs_linear_partition);
#endif