Commit Graph

10 Commits

Author SHA1 Message Date
Miquel Raynal bf3816d28f mtd: nand: ecc-hamming: Use the public nsteps field
The software Hamming ECC engine stores the nsteps variable in its own
private structure while it is also exported as a public ECC field.

Let's get rid of the redundant private one and let's use the
nand_ecc_context structure when possible.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Tested-by: Adam Ford <aford173@gmail.com> #logicpd Torpedo
Link: https://lore.kernel.org/linux-mtd/20210127203020.9574-10-miquel.raynal@bootlin.com
2021-03-11 09:37:28 +01:00
Miquel Raynal 12e0df0c6f mtd: nand: ecc-hamming: Populate the public nsteps field
Advertize the actual number of steps that will actually be used by the
driver by populating the public field.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Tested-by: Adam Ford <aford173@gmail.com> #logicpd Torpedo
Link: https://lore.kernel.org/linux-mtd/20210127203020.9574-4-miquel.raynal@bootlin.com
2021-03-11 09:37:28 +01:00
Miquel Raynal 1771af5cce mtd: nand: ecc-hamming: Clarify the logic around rp17
This code has been written in 2008 and is fine, but in order to keep
robots happy, I think it's time to change a little bit this code just
to clarify the different possible values of eccsize_mult. Indeed, this
variable may only take the value 1 or 2 because step_size, in the case
of the software Hamming ECC engine may only be 256 or 512. Depending
on the value of eccsize_mult, an extra rp17 variable is set, or not
and triggers the following warning:

     smatch warnings:
     ecc_sw_hamming_calculate() error: uninitialized symbol 'rp17'.

As highlighted by Dan Carpenter, if the only possible values for
eccsize_mult are 1 and 2, then the code is fine, but "it's hard to
tell just from looking".

So instead of shifting step_size, let's use a ternary condition to
assign to eccsize_mult the only two possible values and clarify the
driver's logic.

Now that the situation is clarified for humans, ensure rp17 is
initialized to 0 to keep compilers and robots silent as well.

Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20201030172333.28390-1-miquel.raynal@bootlin.com
2020-12-10 22:37:31 +01:00
Miquel Raynal 35fe1b98a0 mtd: nand: ecc-hamming: Create the software Hamming engine
Let's continue introducing the generic ECC engine abstraction in the
NAND subsystem by instantiating a second ECC engine: software
Hamming.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200929230124.31491-20-miquel.raynal@bootlin.com
2020-12-10 22:37:30 +01:00
Miquel Raynal 19b2ce184b mtd: nand: ecc-hamming: Stop using raw NAND structures
This code is meant to be reused by the SPI-NAND core. Now that the
driver has been cleaned and reorganized, use a generic ECC engine
object to store the driver's data instead of accessing members of the
nand_chip structure. This means adding proper init/cleanup helpers.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200929230124.31491-17-miquel.raynal@bootlin.com
2020-12-10 22:37:29 +01:00
Miquel Raynal 90ccf0a019 mtd: nand: ecc-hamming: Rename the exported functions
Prefix by ecc_sw_hamming_ the functions which should be internal only
but are exported for "raw" operations.

Prefix by nand_ecc_sw_hamming_ the other functions which will be used
in the context of the declaration of an Hamming proper ECC engine
object.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200929230124.31491-16-miquel.raynal@bootlin.com
2020-12-10 22:37:29 +01:00
Miquel Raynal b551fa3059 mtd: nand: ecc-hamming: Cleanup and style fixes
Various style fixes.

There is not functional change.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200929230124.31491-15-miquel.raynal@bootlin.com
2020-12-10 22:37:29 +01:00
Miquel Raynal c50e7f3c86 mtd: nand: ecc-hamming: Drop/fix the kernel doc
Some functions should never have been exported (the ones prefixed by
__*), in this case simply drop the documentation, we never want
anybody to use this function from the outside.

For the other functions, enhance the style.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200929230124.31491-14-miquel.raynal@bootlin.com
2020-12-10 22:37:29 +01:00
Miquel Raynal 2dbe0192ef mtd: nand: ecc-hamming: Clarify the driver descriptions
The include file pretends being the header for "ECC algorithm", while
it is just the header for the Hamming implementation. Make this clear
by rewording the sentence.

Do the same with the module description.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200929230124.31491-13-miquel.raynal@bootlin.com
2020-12-10 22:37:29 +01:00
Miquel Raynal e5acf9c862 mtd: nand: ecc-hamming: Move Hamming code to the generic NAND layer
Hamming ECC code might be later re-used by the SPI NAND layer.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200929230124.31491-12-miquel.raynal@bootlin.com
2020-12-10 22:37:29 +01:00