common: fix typos found with codespell ...

Signed-off-by: Yegor Yefremov <yegorslists@googlemail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

imx-bbu-nand-fcb: Mark block as bad when erasing it fails ...

When a block cannot be erased it must be marked as bad. Previously we
accidently ignored the erase failure and the the code just wrote the
firmware into that block which resulted in boot failure.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

Merge branch 'for-next/mtd-gpmi-nand'

mtd: nand-mxs: change API between NAND driver and fcb code ...

The imx-bbu-nand-fcb update handler code calls into the NAND driver
to get the ecc strength and bad block marker position. Change the
API so that only a single function is necessary and not three functions.
Also in future the ecc strength will be configurable via device tree.
This means static parameters like page size / oob size are no longer
enough to calculate the ecc strength and so we store a pointer to our
mtd_info struct in a static global variable.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

mtd: peb: Do not mark as bad in mtd_peb_torture() ...

Both the Kernel and mtd-utils have peb torture functions and both
do not mark the block as bad automatically. Instead, the caller
must mark the block as bad when -EIO is returned from the torture
function. Do the same in barebox. This is necessary as the UBI code
otherwise may mark a block as bad twice: Once indirectly in
mtd_peb_torture() and then directly afterwards.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

imx-bbu-nand-fcb: exchange firmware slots when used firmware is refreshed ...

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

imx-bbu-nand-fcb: refresh unused firmware when it needs refresh ...

So far we only refreshed the unused firmware when it differs from the
used one, but we also have to refresh it when the pages need a cleanup
(-EUCLEAN returned).

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

imx-bbu-nand-fcb: return positive result when firmware needs cleanup ...

The caller of read_firmware() expects a positive return value when a
firmware is readable but needs a cleanup, so return 1 instead of
-EUCLEAN. Without this a firmware will never be refreshed.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

imx-bbu-nand-fcb: make info messages in read_firmware_all() clearer ...

When talking about primary and secondary firmware also say in which slot
they are. Also, when talking about the slot say if it's the primary or
secondary firmware in that slot.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

imx-bbu-nand-fcb: always print info messages in read_firmware_all() ...

read_firmware_all() prints some info messages at the end. There's
one case where we bail out early and no messages are printed. This
is confusing, drop the return and always print messages.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

imx-bbu-nand-fcb: print primary/secondary firmware page numbers ...

When rewriting FCBs print information where the primary and where the
secondary firmware will be. This allows to check consistency with
earlier messages.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

imx-bbu-nand-fcb: print page numbers instead of block numbers ...

The whole file uses NAND page numbers, so for clarity print the
message about where the new firmware is written to with page numbers
aswell. Also refer to the slot the firmware is written into.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

imx-bbu-nand-fcb: Remove unused variable partition_size ...

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

imx-bbu-nand-fcb: Check the required space a bit earlier ...

If the partition size is too small for imx_bbu_nand_update(),
this can lead to an infinite loop in the imx_bbu_firmware_fcb_start_page()
function, because imx_bbu_firmware_max_blocks() returns zero.
Fix this by place imx_bbu_firmware_max_blocks() a bit early.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

imx-bbu-nand: Make locally used functions static ...

To avoid missing prototypes warning.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

imx-bbu-nand-fcb: Workaround ROM checking fingerprint before correcting bitflips ...

The FCB block is protected with a ECC code which can correct 1bit errors
and detect 2bit errors. This works fine for all fields except the
fingerprint marker (Containing "FCB") and the version field. Here the ROM
chooses to check the correct value of the fields *before* running the ECC
correction. Thus a FCB is not used by the ROM anymore when it has a bitflip
in the fingerprint or version. For us this means we have to rewrite the FCB
in this case, so reject the faulty FCB in read_fcb_hamming_13_8() which
triggers a rewrite during the check operation.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

imx-bbu-nand-fcb: Workaround ROM not being able to handle bad blocks properly ...

When reading a firmware image the ROM only checks for a bad block when
advancing the read position, but not if the initial block is good.
Hence we cannot directly point to the first firmware block, but must
instead point to the first *good* firmware block.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

imx-bbu-nand-fcb: Improve error message ...

When printing that a FCB is not readable it's interesting to know which
one is not readable. Print the block number in the message.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

imx-bbu-nand-fcb: fix build on MX28 only ...

This code may be compiled without ARCH_IMX6 present, so it must not
depend on any functions provided by the architecture support.

Fixes: a2618c215bff (imx-bbu-nand-fcb: add support for imx6ul)
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

imx-bbu-nand-fcb: read_firmware_all(): Spell "Secondary firmware" with a capital "S" ...

"Primary firmware" is writte with a capital "P" so adjust "Secondary firmware"
to use a capital "S".

Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

imx-bbu-nand-fcb: add support for imx6ull ...

The i.MX 6ull secures the fcb with bch 40. This is identical to i.MX 6ul.

Signed-off-by: Christian Hemp <c.hemp@phytec.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

imx-bbu-nand-fcb: add support for imx6ul ...

imx6ul secure the fcb with bch 40. The imx-kobs tool use a own modified
bch lib. They reverse the bit order of the data and the ecc.
To use the bch lib in barebox the bytes in the data buffers must be
reversed.
The data layout on nand is bit aligned. But with 40 bits this is not an
issue for imx6ul now.

Signed-off-by: Jan Remmet <J.Remmet@phytec.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

imx-bbu-nand-fcb: split up read_fcb ...

There are other ecc modes for the fcb out there.

Signed-off-by: Jan Remmet <j.remmet@phytec.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

imx-bbu-nand-fcb: avoid double free of dbbt_entries ...

The error path properly frees them already.

Signed-off-by: Lucas Stach <dev@lynxeye.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

imx-bbu-nand-fcb: don't drop error return code ...

bit_to_flip might be negative if any uncorrectable bitflips
occured. Use int instead of unsigned type in order to properly
propagate the error.

Signed-off-by: Lucas Stach <dev@lynxeye.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

imx-bbu-nand-fcb: add missing newline character ...

Signed-off-by: Stefan Christ <s.christ@phytec.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

include: move crc specific stuff to crc.h ...

We have a crc.h, so move our crc function prototypes there to further
cleanup common.h.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

imx-bbu-nand-fcb: Print error message when out of pebs ...

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

imx-bbu-nand-fcb: Make robust against power cuts ...

This patch makes the update to Nand robust against power
failures. With this we make sure that during every step of the
update at least one of the two images on Nand is readable and
valid.

Also this patch makes it possible to refresh/repair the boot
images on Nand. This may become necessary when a previous update
has been interrupted due to a power cut, or when the number of
bitflips is near to the number we can correct. This is also done
in a way that allow power cuts at every step.

We assume the following layout in the Nand flash:

 fwmaxsize = (n_blocks - 4) / 2

 block

 0              ----------------------
                | FCB/DBBT 0         |
 1              ----------------------
                | FCB/DBBT 1         |
 2              ----------------------
                | FCB/DBBT 2         |
 3              ----------------------
                | FCB/DBBT 3         |
 4              ----------------------
                | Firmware slot 0    |
 4 + fwmaxsize  ----------------------
                | Firmware slot 1    |
                ----------------------

When the layout found on the device differs from the above the update
won't be robust, but nevertheless works. Since the layout is changed
to the above during the update, the next update will be robust.

Here's the strategy we use to implement a robust update:

The FCBs contain pointers to the firmware slots in the
Firmware1_startingPage and Firmware2_startingPage fields. Note that
Firmware1_startingPage doesn't necessarily point to slot 0. We
exchange the pointers during update to atomically switch between the
old and the new firmware.

- We read the first valid FCB and the firmware slots.
- We check which firmware slot is currently used by the ROM:
  - if no FCB is found or its layout differs from the above layout,
    continue without robust update
  - if only one firmware slot is readable, the ROM uses it
  - if both slots are readable, the ROM will use slot 0
- Step 1: erase/update the slot currently unused by the ROM
- Step 2: Update FCBs/DBBTs, thereby letting Firmware1_startingPage
          point to the slot we just updated. From this moment
          on the new firmware will be used and running a
          refresh/repair after a power failure after this
          step will complete the update.
- Step 3: erase/update the other firmwre slot
- Step 4: Eventually write FCBs/DBBTs again. This may become
          necessary when step 3 revealed new bad blocks.

Refreshing the firmware which is needed when when blocks
become unreadable due to read disturbance works the same way,
only that the new firmware is the same as the old firmware
and that it will only be written when reading from the device
returns -EUCLEAN indicating that a block needs to be
rewritten.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

imx-bbu-nand-fcb: Print error when writing blocks fails ...

When writing to a block fails the update handler fails relatively
silent. Print an error message in this case.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>