mtd: nand: omap_gpmc: fix: remove bch4 string extant ...

Remove an erroneous bch4 string leftover that
leads to a false ecc mode mapping.

BCH4 support was previously removed by Teresa Remmet:
d316cda 'mtd: nand: omap_gpmc: Remove BCH4 support'

Signed-off-by: Heinrich Toews <heinrich.toews@wago.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

mtd: nand: nand_omap_gpmc: Fix ecc steps ...

The eccsteps where set wrong for OMAP_ECC_BCH8_CODE_HW_ROMCODE.
So the ECC was only corrected for the first 512 bytes chunk of a 2k page.

Moved out the ecc step iteration out of the correcting loop to make
it more alike the generic nand functions. And made sure that
the ECC is caclulated for all chunks.

This patch is based on work of Sascha Hauer.

Fixes commit dec7b4d2bf9c ("mtd: nand_omap_gpmc: fix BCH error correction").

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

mtd: nand_omap_gpmc: fix BCH error correction ...

BCH error detection and correction was only looking at the first
of four syndrome polynomials, which meant it was failing to detect
and correct bitflips in the last 3/4 of the data. In effect, only
the first 512 bytes of a 2048 byte page were being protected by ECC.

The syndrome polynomials (BCH error codes) are stored in the NAND's
OOB, each of which protects 512 bytes of data. The driver used
eccsteps = 1 which effectively made it only use the first polynomial,
and therefore was only protecting the first 512 bytes of the page.

The fix is to pull over a bit of code from the kernel's
omap_correct_data() that sets eccsteps = 4 when the page size is 2048
bytes and hardware ECC is being used.

Signed-off-by: Matt Reimer <mreimer@sdgsystems.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

mtd: nand: omap_gpmc: Fix bitflips in empty page ...

When using BCH8 decoding, bitflips in an empty page are
not checked. This can cause issues if UBI/UBIFS are used.
Extend the omap_correct_bch() function to check for them.

Code is based on linux mainline mtd/nand/omap2.c driver.

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

mtd: nand: omap_gpmc: Remove BCH4 support ...

This has no users and seems to be untested. Removed it.

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

driver: replace dev_request_mem_region with dev_request_mem_resource ...

dev_request_mem_region doesn't work properly one some SoCs on which
PTR_ERR() values clash with valid return values from dev_request_mem_region.
Replace them with dev_request_mem_resource where possible.

This patch has been generated with the following semantic patch:

// <smpl>
@@
expression d;
expression n;
expression io;
identifier func;
@@
func(...) {
+struct resource *iores;
<+...
-io = dev_request_mem_region(d, n);
-if (IS_ERR(io)) {
+iores = dev_request_mem_resource(d, n);
+if (IS_ERR(iores)) {
...
-	return PTR_ERR(io);
-}
+	return PTR_ERR(iores);
+}
+io = IOMEM(iores->start);
...+>
}

@@
expression d;
expression n;
expression io;
identifier func;
@@
func(...) {
+struct resource *iores;
<+...
-io = dev_request_mem_region(d, n);
-if (IS_ERR(io)) {
+iores = dev_request_mem_resource(d, n);
+if (IS_ERR(iores))
-	return PTR_ERR(io);
-}
+	return PTR_ERR(iores);
+io = IOMEM(iores->start);
...+>
}

@@
expression d;
expression n;
expression io;
identifier func;
@@
func(...) {
+struct resource *iores;
<+...
-io = dev_request_mem_region(d, n);
-if (IS_ERR(io)) {
-	ret = PTR_ERR(io);
+iores = dev_request_mem_resource(d, n);
+if (IS_ERR(iores)) {
+	ret = PTR_ERR(iores);
...
}
+io = IOMEM(iores->start);
...+>
}

@@
expression d;
expression n;
expression io;
identifier func;
@@
func(...) {
+struct resource *iores;
<+...
-io = dev_request_mem_region(d, n);
+iores = dev_request_mem_resource(d, n);
+if (IS_ERR(iores))
+	return PTR_ERR(iores);
+io = IOMEM(iores->start);
...+>
}

@@
identifier func;
@@
func(...) {
<+...
struct resource *iores;
-struct resource *iores;
...+>
}
// </smpl>

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

mtd: nand_omap_gpmc: Fix ecc check for bch8 romcode ...

The bch8 romcode was only checked and corrected for the
first 512 bytes of a 2048 byte page. Set interation counter
and eccsizes correct for the different bch types.

Tested OMAP_ECC_BCH8_CODE_HW and OMAP_ECC_BCH8_CODE_HW_ROMCODE.

Reported-by: Gabor Janak <g.janak@agilion.de>
Signed-off-by: Teresa Gámez <t.gamez@phytec.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

mtd: nand_omap_gpmc: Remove unused code ...

The ecc layout structs are not used anywhere.

Signed-off-by: Teresa Gámez <t.gamez@phytec.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

mtd: nand: omap: Fix OMAP_ECC_BCH8_CODE_HW ecc mode ...

This is broken since:

| commit 00f119a
| Author: Sascha Hauer <s.hauer@pengutronix.de>
| Date:   Fri Aug 1 14:09:48 2014 +0200
|
|     mtd: omap gpmc: fix ecc bytes/size
|
|     The ecc bytes / size are per subpage, not per page.
|
|     Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

The ecc code in omap_correct_data() expects to correct a whole page
at once, so we must tell the nand layer that we have 4 * 13 bytes of
ecc bytes and 4 * 512 bytes of ecc size. Otherwise the NAND layer will
iterate over 512 byte steps over a page and call the .correct callback
each time.

This only works for 2k pagesize and needs revisit once other page sizes
shall be supported. It would be better to tell the nand layer the real
ecc bytes (13) and ecc size (512) instead and drop the iteration in
omap_correct_bch(). However, this needs better testing so it isn't done
here now.

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

mtd: omap gpmc: reserve 14 byte/subpage for ECC in BCH8 romcode ...

As done in the Kernel. The Kernel has a comment this is done to
be compatible with the ROM code.

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

mtd: omap gpmc: fix ecc bytes/size ...

The ecc bytes / size are per subpage, not per page.

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

mtd: omap gpmc: Turn debug message into dev_dbg ...

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

mtd: omap gpmc: Use dev_add_param_enum ...

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

Merge branch 'for-next/mtd'

mtd: nand: update to v3.11-rc1 ...

This updates the NAND stuff to Linux-3.11-rc1. It is synchronized
as best as we can get:

- locks removed
- The splitting in different files we had to better support different
  features has been dropped. Instead this is now done mostly with the
  use of __maybe_unused

Some barebox adjustments are forward ported, like:

- Allow partial page writes
- Optionally allow to erase bad blocks
- check for all_ff before writing a page

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

mtd: introduce ecc strength ...

This introduces the ecc stength fields in the structures and fills
them in, but leaves them unused right now.

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

mtd: nand: omap: do not set write callback if mtd write is disabled ...

Saves a few bytes of binary space.

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

mtd: nand: register nand flashes with nand specific function ...

This allows us to have some NAND specific stuff during registration,
like for example adding NAND specific device parameters.

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

Use new device_platform_driver() macro for drivers ...

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

ARM omap: include individual SoC files ...

- remove mach/silicon.h and include omap?-silicon.h directly
- include mach/omap?-clock.h directly where needed

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

mtd: add parent support ...

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

switch all platform_bus device/driver registering to platform_driver/device_register ...

now register_driver and register_device are for bus only usage.

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>

mtd OMAP NAND: implement buswidth autodetection support ...

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

mtd OMAP NAND: Use prefetch engine ...

Use the prefetch engine to improve NAND performance. The howto
is derived from the Kernel. Unlike the kernel we do not make
the access mode configurable.

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

mtd OMAP NAND: Fix dev_ready handling ...

- dev_ready is supposed to return whether the device is ready or
  not, not to poll until the device is ready.
- dev_ready should return true for ready and false for not ready
- waitpin polarity is not needed (at least the kernel does not have it)
- wait_mon_mask must be 32bit.

The code was unused since no board specified a wait pin, so no breakage
included. This also removes the now unused timeout variable from
platformdata.

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

mtd omap: add prefix to omap specific decode_bch function ...

So that it does not collide with our generic decode_bch function.

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

Revert "mtd omap nand: fix driver without CONFIG_PARAMETER" ...

This reverts commit 7762f96.

already applied by d002818

    fix gpmc_nand_probe without param support

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

mtd omap nand: fix driver without CONFIG_PARAMETER ...

With CONFIG_PARAMETER unset the driver never calls omap_gpmc_eccmode.
Fix it.

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

fix gpmc_nand_probe without param support ...

commit 30de24d param: add config to disable it
removes param support for xloader configurations. Set param eccmode calls
omap_gpmc_eccmode and so nand_scan_tail. So nand fails without param support

Call omap_gpmc_eccmode directly if CONFIG_PARAMETER is not enabled
to fix that.

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

nand_omap_gpmc: fix return value ...

Fix return value, to notify if ecc
correction appeared.

Signed-off-by: Alexander Aring <a.aring@phytec.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>