Another part of the preparation for switching to an array...
Signed-off-by: David Woodhouse <dwmw2@infradead.org>

As the first step towards eliminating the ref->next_phys member and saving
memory by using an _array_ of struct jffs2_raw_node_ref per eraseblock,
stop the write functions from allocating their own refs; have them just
_reserve_ the appropriate number instead. Then jffs2_link_node_ref() can
just fill them in.

Use a linked list of pre-allocated refs in the superblock, for now. Once
we switch to an array, it'll just be a case of extending that array.
Signed-off-by: David Woodhouse <dwmw2@infradead.org>

Move the define out of the middle of the code and add an
appropriate comment.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

The previous change of the command / hardware control allows to
remove the write_byte/word functions completely, as their only
user were nand_command and nand_command_lp.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

The hwcontrol function enforced a step by step state machine
for any kind of hardware chip access. Let the hardware driver
know which control bits are set and inform it about a change
of the control lines. Let the hardware driver write out the
command and address bytes directly. This gives a peformance
advantage for address bus controlled chips and simplifies the
quirks in the hardware drivers.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

The previous _ecc removal / cleanup broke (i)nftl module usage.
Export the missing symbol.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

Both drivers can not be fixed and compiled due to missing header files.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

MTD clients are agnostic of FLASH which needs ECC suppport.
Remove the functions and fixup the callers.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

These functions were never implemented and added only bloat to
partition and concat code.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

NAND writev(_ecc) support is not longer necessary. Remove it.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

Fix the diskonchip ecc setup.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

Fix the broken prototype
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

First step of modularizing ECC support.
- Move ECC related functionality into a seperate embedded data structure
- Get rid of the hardware dependend constants to simplify new ECC models
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

Seperate functionality out of nand_scan so the code is more
readable. No functional change. First step of simplifying
the nand driver.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

The NAND driver used a mix of unsigned char, u_char amd uint8_t
data types. Consolidate to uint8_t usage
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

The writev based write buffer implementation was far to complex as
in most use cases the write buffer had to be handled anyway.
Simplify the write buffer handling and use mtd->write instead.

From extensive testing no performance impact has been noted.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

NDFC NAND Flash controller is embedded in PPC EP44x SoCs.
Add platform driver based support.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

Add the data structures necessary to provide platform device support
for NAND
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

Replace the chip lock by a the controller lock. For simple drivers a
dummy controller structure is created by the scan code.
This simplifies the locking algorithm in nand_get/release_chip().
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

Unrolling the loops produces denser and much faster code.
Add a config switch which allows to select the byte order of the
resulting ecc code. The current Linux implementation has a byte
swap versus the SmartMedia specification
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

We don't need the upper layers to deal with the physical offset. It's
_always_ c->nextblock->offset + c->sector_size - c->nextblock->free_size
so we might as well just let the actual write functions deal with that.
Signed-off-by: David Woodhouse <dwmw2@infradead.org>

o Add a flag MTD_BIT_WRITEABLE for devices that allow single bits to be
  cleared.
o Replace MTD_PROGRAM_REGIONS with a cleared MTD_BIT_WRITEABLE flag for
  STMicro and Intel Sibley flashes with internal ECC.  Those flashes
  disallow clearing of single bits, unlike regular NOR flashes, so the
  new flag models their behaviour better.
o Remove MTD_ECC.  After the STMicro/Sibley merge, this flag is only set
  and never checked.
Signed-off-by: Joern Engel <joern@wh.fh-wedel.de>

In 2002, STMicro started producing NOR flashes with internal ECC protection
for small blocks (8 or 16 bytes).  Support for those flashes was added by me.
In 2005, Intel Sibley flashes copied this strategy and Nico added support for
those.  Merge the code for both.
Signed-off-by: Joern Engel <joern@wh.fh-wedel.de>

At least two flashes exists that have the concept of a minimum write unit,
similar to NAND pages, but no other NAND characteristics.  Therefore, rename
the minimum write unit to "writesize" for all flashes, including NAND.
Signed-off-by: Joern Engel <joern@wh.fh-wedel.de>

Two flags exist to decide whether a device is writeable or not.  None of
those two flags is checked for independently, so they are clearly redundant,
if not an invitation to bugs.  This patch removed both of them, replacing
them with a single new flag.
Signed-off-by: Joern Engel <joern@wh.fh-wedel.de>

We'll be using a proper list of nodes in the jffs2_xattr_datum and
jffs2_xattr_ref structures, because the existing code to overwrite
them is just broken. Put it in the common part at the front of the
structure which is shared with the jffs2_inode_cache, so that the
jffs2_link_node_ref() function can do the right thing.
Signed-off-by: David Woodhouse <dwmw2@infradead.org>

In a couple of places, we assume that what's at the end of the
->next_in_ino list is a struct jffs2_inode_cache. Let's check
for that, since we expect it to change soon.
Signed-off-by: David Woodhouse <dwmw2@infradead.org>

Let's avoid the potential for forgetting to set ref->next_in_ino, by doing
it within jffs2_link_node_ref() instead.

This highlights the ugliness of what we're currently doing with
xattr_datum and xattr_ref structures -- we should find a nicer way of
dealing with that.
Signed-off-by: David Woodhouse <dwmw2@infradead.org>

Signed-off-by: David Woodhouse <dwmw2@infradead.org>

When filing REF_OBSOLETE nodes, we'd add their size to the global
'dirty_size' count, but then to the eraseblock's 'used_size' count.
That's not clever.
Signed-off-by: David Woodhouse <dwmw2@infradead.org>

I added an argument to the real function...
Signed-off-by: David Woodhouse <dwmw2@infradead.org>

Signed-off-by: David Woodhouse <dwmw2@infradead.org>

The previous code wouldn't work correctly on architectures which have a
non-empty MODULE_SYMBOL_PREFIX, and this version is neater if slightly
less optimal in the built-in case.
Signed-off-by: David Woodhouse <dwmw2@infradead.org>

The patch below adds support for the NAND device on the Amstrad Delta.
This is a 32MiB 8bit Toshiba device, with the data bus connected to the
OMAP MPUIO pins and ALE, CLE, NCE, NRE, NWE and NWP all connected to the
Delta's latch2 16bit latch.
Signed-Off-By: Jonathan McDowell <noodles@earth.li>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>

Well, almost. We'll actually keep a 'TEST_TOTLEN' macro set for now, and keep
doing some paranoia checks to make sure it's all working correctly. But if
TEST_TOTLEN is unset, the size of struct jffs2_raw_node_ref drops from 16
bytes to 12 on 32-bit machines. That's a saving of about half a megabyte of
memory on the OLPC prototype board, with 125K or so nodes in its 512MiB of
flash.
Signed-off-by: David Woodhouse <dwmw2@infradead.org>

We can't use jffs2_scan_dirty_space() because it doesn't do any locking; it's
only for use at scan time -- hence the 'scan' in the name.

Also, don't allocate refs while we have c->erase_completion_lock held.
Signed-off-by: David Woodhouse <dwmw2@infradead.org>