Commit Graph

367 Commits

Author SHA1 Message Date
Brian Norris 2cbaf5491c This pull request contains the following infrastructure changes:
* introduction of the ECC algo concept to extend the ECC mode one
 * replacement of the nand_ecclayout infrastructure by something more
   future-proof.
 * addition of an mtd-activity led trigger to replace the nand-activity
   one
 
 And a bunch of specific NAND driver improvements/fixes. Here are the
 changes that are worth mentioning:
 * rework of the OMAP GPMC and NAND drivers
 * prepare the sunxi NAND driver to receive DMA support
 * handle bitflips in erased pages on GPMI revisions that do not support
   this in hardware.
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Merge tag 'nand/for-4.7' of github.com:linux-nand/linux

Updates from Boris Brezillon:

This pull request contains the following infrastructure changes:
* introduction of the ECC algo concept to extend the ECC mode one
* replacement of the nand_ecclayout infrastructure by something more
  future-proof.
* addition of an mtd-activity led trigger to replace the nand-activity
  one

And a bunch of specific NAND driver improvements/fixes. Here are the
changes that are worth mentioning:
* rework of the OMAP GPMC and NAND drivers
* prepare the sunxi NAND driver to receive DMA support
* handle bitflips in erased pages on GPMI revisions that do not support
  this in hardware.

* tag 'nand/for-4.7' of github.com:linux-nand/linux: (152 commits)
  mtd: brcmnand: respect ECC algorithm set by NAND subsystem
  gpmi-nand: Handle ECC Errors in erased pages
  Documentation: devicetree: deprecate "soft_bch" nand-ecc-mode value
  mtd: nand: add support for "nand-ecc-algo" DT property
  mtd: mtd: drop NAND_ECC_SOFT_BCH enum value
  mtd: drop support for NAND_ECC_SOFT_BCH as "soft_bch" mapping
  mtd: nand: read ECC algorithm from the new field
  mtd: nand: fsmc: validate ECC setup by checking algorithm directly
  mtd: nand: set ECC algorithm to Hamming on fallback
  staging: mt29f_spinand: set ECC algorithm explicitly
  CRIS v32: nand: set ECC algorithm explicitly
  mtd: nand: atmel: set ECC algorithm explicitly
  mtd: nand: davinci: set ECC algorithm explicitly
  mtd: nand: bf5xx: set ECC algorithm explicitly
  mtd: nand: omap2: Fix high memory dma prefetch transfer
  mtd: nand: omap2: Start dma request before enabling prefetch
  mtd: nandsim: add __init attribute
  mtd: nand: move of_get_nand_xxx() helpers into nand_base.c
  mtd: nand: sh_flctl: rely on generic DT parsing done in nand_scan_ident()
  mtd: nand: mxc: rely on generic DT parsing done in nand_scan_ident()
  ...
2016-05-05 18:04:53 -07:00
Rafał Miłecki ba4f46b28f mtd: nand: add support for "nand-ecc-algo" DT property
So far it was only possible to specify ECC algorithm using "soft" and
"soft_bch" values of nand-ecc-mode prop. There wasn't a way to specify
it for a hardware ECC mode.

Now that we have independent field in NAND subsystem for storing info
about ECC algorithm we may also add support for this new DT property.

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
2016-05-05 23:55:14 +02:00
Rafał Miłecki e4225ae823 mtd: mtd: drop NAND_ECC_SOFT_BCH enum value
This value should not be part of nand_ecc_modes_t as it specifies
algorithm not a mode. We successfully managed to introduce new "algo"
field which is respected now.

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
2016-05-05 23:55:13 +02:00
Rafał Miłecki ae211bcfa1 mtd: drop support for NAND_ECC_SOFT_BCH as "soft_bch" mapping
There isn't any difference between handling NAND_ECC_SOFT and
NAND_ECC_SOFT_BCH now. What matters is the new field called "algo".
Please note we're keeping backward DT compatibility. We are still
treating "soft_bch" value as the one setting Hamming algorithm, it's
just handled in of_get_nand_ecc_algo now.

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
2016-05-05 23:55:13 +02:00
Rafał Miłecki 06f384c901 mtd: nand: read ECC algorithm from the new field
Now we have all drivers properly setting this new field we can start
using it. For a very short period of time we should support both values:
NAND_ECC_SOFT and NAND_ECC_SOFT_BCH treating them the same. It's because
of_get_nand_ecc_mode may still be setting NAND_ECC_SOFT_BCH.

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
2016-05-05 23:55:10 +02:00
Rafał Miłecki e9d4faed71 mtd: nand: set ECC algorithm to Hamming on fallback
This is part of process deprecating NAND_ECC_SOFT_BCH (and switching to
enum nand_ecc_algo).

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
2016-05-05 23:52:04 +02:00
Boris Brezillon d48f62b9a0 mtd: nand: move of_get_nand_xxx() helpers into nand_base.c
Now that all drivers go through nand_set_flash_node() to parse the generic
NAND properties, we can move all of_get_nand_xxx() helpers in to
nand_base.c, make them static and remove of_mtd.c and of_mtd.h.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
2016-05-05 23:52:00 +02:00
Boris Brezillon 7f2b092c9e mtd: nand: kill the ecc->layout field
Now that all NAND drivers have switched to mtd_ooblayout_ops, we can kill
the ecc->layout field.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
2016-05-05 23:51:50 +02:00
Boris Brezillon 7cf9c19a83 mtd: nand: bch: switch to mtd_ooblayout_ops
Replace the nand_ecclayout definition by the equivalent mtd_ooblayout_ops
definition.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
2016-05-05 23:51:26 +02:00
Boris Brezillon 41b207a70d mtd: nand: implement the default mtd_ooblayout_ops
Replace the default nand_ecclayout definitions for large and small page
devices with the equivalent mtd_ooblayout_ops.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
2016-04-19 22:05:56 +02:00
Boris Brezillon 70d105e4ee mtd: nand: use mtd_set_ecclayout() where appropriate
Use the mtd_set_ecclayout() helper instead of directly assigning the
mtd->ecclayout field.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
2016-04-19 22:05:54 +02:00
Boris Brezillon 846031d3e1 mtd: nand: core: use mtd_ooblayout_xxx() helpers where appropriate
The mtd_ooblayout_xxx() helper functions have been added to avoid direct
accesses to the ecclayout field, and thus ease for future reworks.
Use these helpers in all places where the oobfree[] and eccpos[] arrays
where directly accessed.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
2016-04-19 22:05:49 +02:00
Boris Brezillon 9d02fc2a51 mtd: nand: export default read/write oob functions
Export the default read/write oob functions (for the standard and syndrome
scheme), so that drivers can use them for their raw implementation and
implement their own functions for the normal oob operation.

This is required if your ECC engine is capable of fixing some of the OOB
data. In this case you have to overload the ->read_oob() and ->write_oob(),
but if you don't specify the ->read/write_oob_raw() functions they are
assigned to the ->read/write_oob() implementation, which is not what you
want.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
2016-04-19 22:05:38 +02:00
Ezequiel García 11eaf6df1c mtd: nand: Remove BUG() abuse in nand_scan_tail
There's no reason to BUG() when parameters are being
validated. Drivers can get things wrong, and it's much nicer
to just throw a noisy warn and fail gracefully, than calling
BUG() and throwing the whole system down the drain.

Signed-off-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Reviewed-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
2016-04-19 22:04:52 +02:00
Rafał Miłecki 79082457d7 mtd: nand: set ECC algorithm in nand_dt_init
Use recently added of_get_nand_ecc_algo for that.

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
2016-04-19 22:04:49 +02:00
Ezequiel Garcia 4c7e054f08 mtd: nand: Remove the "nand-disk" LED trigger
This commit removes the "nand-disk" LED trigger from the
NAND code.

A trigger with the same name is already available selecting
LEDS_TRIGGER_MTD. Note that "nand-disk" trigger is being
deprecated in favor of the "mtd" trigger.

Signed-off-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
2016-04-13 10:23:15 +02:00
Ezequiel García 20c07a5bf0 mtd: nand: Drop mtd.owner requirement in nand_scan
Since commit 807f16d4db ("mtd: core: set some defaults
when dev.parent is set"), it's now legal for drivers
to call nand_scan and nand_scan_ident without setting
mtd.owner.

Drop the check and while at it remove the BUG() abuse.

Fixes: 807f16d4db ("mtd: core: set some defaults when dev.parent is set")
Signed-off-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com>
[Brian: editorial note - while commit 807f16d4db wasn't explicitly
    broken, some follow-up commits in the v4.4 release broke a few
    drivers, since they would hit this BUG() if they used nand_scan()
    and were built as modules]
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2016-04-02 23:03:51 -07:00
Brian Norris 6871c1b96d mtd: nand: remove kerneldoc for removed function parameter
The 'getchip' parameter is gone as of commit 9f3e04297b ("mtd: nand:
don't select chip in nand_chip's block_bad op"), so kill the doc with
it.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com>
2016-03-11 09:41:19 -08:00
Archit Taneja 9f3e04297b mtd: nand: don't select chip in nand_chip's block_bad op
One of the arguments passed to struct nand_chip's block_bad op is
'getchip', which, if true, is supposed to get and select the nand device,
and later unselect and release the device.

This op is intended to be replaceable by drivers. The drivers shouldn't
be responsible for selecting/unselecting chip. Like other ops, the chip
should already be selected before the block_bad op is called.

Remove the getchip argument from the block_bad op and
nand_block_checkbad. Move the chip selection to nand_block_isbad, since it
is the only caller to nand_block_checkbad which requires chip selection.

Modify nand_block_bad (the default function for the op) such that it
doesn't select the chip.

Remove the getchip argument from the bad_block funcs in cafe_nand,
diskonchip and docg4 drivers.

Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Archit Taneja <architt@codeaurora.org>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2016-03-10 10:52:21 -08:00
Boris BREZILLON a8c65d504e mtd: nand: simplify nand_bch_init() usage
nand_bch_init() requires several arguments which could directly be deduced
from the mtd device. Get rid of those useless parameters.

nand_bch_init() is also requiring the caller to provide a proper eccbytes
value, while this value could be deduced from the ecc.size and
ecc.strength value. Fallback to eccbytes calculation when it is set to 0.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2016-03-07 16:23:09 -08:00
Boris BREZILLON 29f1058a90 mtd: create an mtd_oobavail() helper and make use of it
Currently, all MTD drivers/sublayers exposing an OOB area are
doing the same kind of test to extract the available OOB size
based on the mtd_info and mtd_oob_ops structures.
Move this common logic into an inline function and make use of it.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Suggested-by: Priit Laes <plaes@plaes.org>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2016-03-07 16:23:09 -08:00
Boris BREZILLON f5b8aa78ef mtd: kill the ecclayout->oobavail field
ecclayout->oobavail is just redundant with the mtd->oobavail field.
Moreover, it prevents static const definition of ecc layouts since the
NAND framework is calculating this value based on the ecclayout->oobfree
field.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2016-03-07 16:23:09 -08:00
Brian Norris 9ebfdf5b18 mtd: nand: check status before reporting timeout
In commit b70af9bef4 ("mtd: nand: increase ready wait timeout and
report timeouts"), we increased the likelihood of scheduling during
nand_wait(). This makes us more likely to hit the time_before(...)
condition, since a lot of time may pass before we get scheduled again.

Now, the loop was already buggy, since we don't check if the NAND is
ready after exiting the loop; we simply print out a timeout warning. Fix
this by doing a final status check before printing a timeout message.

This isn't actually a critical bug, since the only effect is a false
warning print. But too many prints never hurt anyone, did they? :)

Side note: perhaps I'm not smart enough, but I'm not sure what the best
policy is for this kind of loop; do we busy loop (i.e., no
cond_resched()) to keep the lowest I/O latency (it's not great if the
resched is delaying Richard's system ~400ms)? Or do we allow
rescheduling, to play nice with the rest of the system (since some
operations can take quite a while)?

Reported-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Reviewed-by: Richard Weinberger <richard@nod.at>
Reviewed-by: Harvey Hunt <harvey.hunt@imgtec.com>
2016-03-07 13:51:11 -08:00
Boris BREZILLON 40cbe6eee9 mtd: nand: use nand_check_erased_ecc_chunk in default ECC read functions
The default NAND read functions are relying on the underlying controller
driver to correct bitflips, but some of those controllers cannot properly
fix bitflips in erased pages.
Check for bitflips in erased pages in default core functions if the driver
delegated the this check by setting the NAND_ECC_GENERIC_ERASED_CHECK flag.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Tested-by: Franklin S Cooper Jr. <fcooper@ti.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2016-01-06 18:48:20 -08:00
Brian Norris f7a8e38f07 mtd: nand: assign reasonable default name for NAND drivers
Commits such as commit 853f1c58c4 ("mtd: nand: omap2: show parent
device structure in sysfs") attempt to rely on the core MTD code to set
the MTD name based on the parent device. However, nand_base tries to set
a different default name according to the flash name (e.g., extracted
from the ONFI parameter page), which means NAND drivers will never make
use of the MTD defaults. This is not the intention of commit
853f1c58c4.

This results in problems when trying to use the cmdline partition
parser, since the MTD name is different than expected. Let's fix this by
providing a default NAND name, where possible.

Note that this is not really a great default name in the long run, since
this means that if there are multiple MTDs attached to the same
controller device, they will have the same name. But that is an existing
issue and requires future work on a better controller vs. flash chip
abstraction to fix properly.

Fixes: 853f1c58c4 ("mtd: nand: omap2: show parent device structure in sysfs")
Reported-by: Heiko Schocher <hs@denx.de>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Tested-by: Heiko Schocher <hs@denx.de>
Cc: Heiko Schocher <hs@denx.de>
Cc: Frans Klaver <fransklaver@gmail.com>
Cc: <stable@vger.kernel.org>
2016-01-06 14:52:41 -08:00
Helmut Schaa 44991b3d19 mtd: nand: Disable subpage writes for drivers without ecc->hwctl
nand_write_subpage_hwecc causes a crash if the driver did not register
ecc->hwctl or ecc->calculate. Fix this by disabling subpage writes if
ecc->hwctl or ecc->calculate is not provided by the driver.

This behavior was introduced in commit 837a6ba4f3
"mtd: nand: subpage write support for hardware based ECC schemes".

This fixes a crash with fsl_elbc_nand and maybe others:

Unable to handle kernel paging request for instruction fetch
Faulting instruction address: 0x00000000
Oops: Kernel access of bad area, sig: 11 [#1]
SMP NR_CPUS=2 P1020 RDB
Modules linked in: ath9k ath9k_common pppoe ppp_async option iptable_nat ath9k_hw ath usb_wwan pppox ppp_generic nf_nat_ipv4 nf_conntrack_ipv4 mac80211 ipt_MASQUERADE cfg80211 xt_time xt_tcpudp xt_state xt_quota xt_policy xt_pkttype xt_owner xt_nat xt_multiport xt_mh
CPU: 1 PID: 2161 Comm: ubiformat Not tainted 3.10.26 #6
task: efbc2700 ti: c7950000 task.ti: c7950000
NIP: 00000000 LR: c01a495c CTR: 00000000
REGS: c7951cb0 TRAP: 0400   Not tainted  (3.10.26)
MSR: 00029000 <CE,EE,ME>  CR: 24002028  XER: 00000000

GPR00: c01a4b6c c7951d60 efbc2700 ef84b000 00000001 00000000 000001ff c7800500
GPR08: 00000000 00000000 efae5e40 c01a4ae4 24002022 10023418 c7951e5c c7800500
GPR16: c017b6a8 00000000 0000003f c053404c 00000000 00000004 00000000 00000003
GPR24: 00000010 00000200 ef84b000 c7800d00 c7800000 c7800500 ef84b1c8 00000000
NIP [00000000]   (null)
LR [c01a495c] nand_write_subpage_hwecc+0x74/0x174
Call Trace:
[c7951d60] [c7951d64] 0xc7951d64 (unreliable)
[c7951da0] [c01a4b6c] nand_write_page+0x88/0x198
[c7951dd0] [c01a5f7c] nand_do_write_ops+0x2f4/0x39c
[c7951e40] [c01a61e0] nand_write+0x58/0x84
[c7951e80] [c019e29c] mtdchar_write+0x1dc/0x28c
[c7951ef0] [c00aba84] vfs_write+0xcc/0x1ac
[c7951f10] [c00ac04c] SyS_write+0x4c/0x90
[c7951f40] [c000cd84] ret_from_syscall+0x0/0x3c
 --- Exception: c01 at 0x48050ed8
     LR = 0x100071b8
 Instruction dump:
 XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX
 XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX
 ---[ end trace 161d3c65a2a15cb8 ]---

Kernel panic - not syncing: Fatal exception

[Brian: editorial note - we've applied a previous fix for the driver in
question (fsl_elbc_nand) long ago:
commit f034d87def ("mtd: eLBC NAND: fix subpage write support")
but this still makes sense, and it could solve issues on some other
unforseen driver.]

Cc: Pekon Gupta <pekon.gupta@gmail.com>
Cc: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Cc: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Helmut Schaa <helmut.schaa@googlemail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-12-18 18:15:28 -08:00
Boris BREZILLON 29574ede09 mtd: nand: kill the chip->flash_node field
Now that the nand_chip struct directly embeds an mtd_info struct we can
get rid of the ->flash_node field and forward set/get_flash_node requests
to the MTD layer.

As a side effect, we no longer need the mtd_set_of_node() call done in
nand_dt_init().

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-12-18 13:22:53 -08:00
Boris BREZILLON 7194a29a9b mtd: nand: simplify nand_dt_init() usage
nand_dt_init() function requires 3 arguments where it actually needs one
(dn and mtd can both be retrieved from chip). Drop these parameters.

Testing for dn != NULL inside nand_dt_init() also helps simplifying the
caller code.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-12-18 13:22:50 -08:00
Boris BREZILLON 862eba519e mtd: nand: make use of mtd_to_nand() in NAND core code
mtd_to_nand() was recently introduced to avoid direct access to the
mtd->priv field. Update core code to use mtd_to_nand().

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-12-08 10:46:14 -08:00
Brian Norris e727ee86d9 Merge MTD 4.4 development into MTD -next
We need to be able to build the jz4740_nand driver.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-11-16 14:46:13 -08:00
Brian Norris 9ca641b0f0 mtd: nand: fix shutdown/reboot for multi-chip systems
If multiple NAND chips are registered to the same controller, then when
rebooting the system, the first one will grab the controller lock, while
the second will wait forever for the first one to release it. i.e., a
classic deadlock.

This problem was solved for a similar case (suspend/resume) back in
commit 6b0d9a8412 ("mtd: nand: fix multi-chip suspend problem"), and
the shutdown state really isn't much different for us, so rather than
adding a new special case to nand_get_device(), we can just overload the
FL_PM_SUSPENDED state.

Now, multiple chips can "get" the same controller lock (preventing
further I/O), while we still allow other chips to pass through
nand_shutdown().

Original report:
http://thread.gmane.org/gmane.linux.drivers.mtd/59726
http://lists.infradead.org/pipermail/linux-mtd/2015-July/059992.html

Fixes: 72ea403669 ("mtd: nand: added nand_shutdown")
Reported-by: Andrew E. Mileski <andrewm@isoar.ca>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Cc: Scott Branden <sbranden@broadcom.com>
Cc: Andrew E. Mileski <andrewm@isoar.ca>
Acked-by: Scott Branden <sbranden@broadcom.com>
Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com>
2015-11-16 10:51:39 -08:00
Boris BREZILLON 44ec23c9ec mtd: nand: convert to nand_get_flash_node()
Used semantic patch with 'make coccicheck MODE=patch COCCI=script.cocci':

---8<----
virtual patch

@@
struct nand_chip c;
struct nand_chip *cp;
@@
(
-(cp)->flash_node
+nand_get_flash_node(cp)
|
-(c).flash_node
+nand_get_flash_node(&c)
)
---8<----

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-11-11 15:54:15 -08:00
Brian Norris 3e63b26bdd mtd: {nand,spi-nor}: assign MTD of_node
We should pass along our flash DT node to the MTD layer, so it can set
up ofpart for us.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com>
2015-11-11 13:45:13 -08:00
Alex Smith b70af9bef4 mtd: nand: increase ready wait timeout and report timeouts
If nand_wait_ready() times out, this is silently ignored, and its
caller will then proceed to read from/write to the chip before it is
ready. This can potentially result in corruption with no indication as
to why.

While a 20ms timeout seems like it should be plenty enough, certain
behaviour can cause it to timeout much earlier than expected. The
situation which prompted this change was that CPU 0, which is
responsible for updating jiffies, was holding interrupts disabled
for a fairly long time while writing to the console during a printk,
causing several jiffies updates to be delayed. If CPU 1 happens to
enter the timeout loop in nand_wait_ready() just before CPU 0 re-
enables interrupts and updates jiffies, CPU 1 will immediately time
out when the delayed jiffies updates are made. The result of this is
that nand_wait_ready() actually waits less time than the NAND chip
would normally take to be ready, and then read_page() proceeds to
read out bad data from the chip.

The situation described above may seem unlikely, but in fact it can be
reproduced almost every boot on the MIPS Creator Ci20.

Therefore, this patch increases the timeout to 400ms. This should be
enough to cover cases where jiffies updates get delayed. In nand_wait()
the timeout was previously chosen based on whether erasing or
programming. This is changed to be 400ms unconditionally as well to
avoid similar problems there. nand_wait() is also slightly refactored
to be consistent with nand_wait{,_status}_ready(). These changes should
have no effect during normal operation.

Debugging this was made more difficult by the misleading comment above
nand_wait_ready() stating "The timeout is caught later" - no timeout was
ever reported, leading me away from the real source of the problem.
Therefore, a pr_warn() is added when a timeout does occur so that it is
easier to pinpoint similar problems in future.

Signed-off-by: Alex Smith <alex.smith@imgtec.com>
Signed-off-by: Harvey Hunt <harvey.hunt@imgtec.com>
Reviewed-by: Niklas Cassel <niklas.cassel@axis.com>
Cc: Alex Smith <alex@alex-smith.me.uk>
Cc: Zubair Lutfullah Kakakhel <Zubair.Kakakhel@imgtec.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Niklas Cassel <niklas.cassel@axis.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-10-26 13:02:51 -07:00
Boris BREZILLON 45aaeff947 mtd: nand: pass page number to ecc->write_xxx() methods
The ->read_xxx() methods are all passed the page number the NAND controller
is supposed to read, but ->write_xxx() do not have such a parameter.

This is a problem if we want to properly implement data
scrambling/randomization in order to mitigate MLC sensibility to repeated
pattern: to prevent bitflips in adjacent pages in the same block we need
to avoid repeating the same pattern at the same offset in those pages,
hence the randomizer/scrambler engine need to be passed the page value
in order to adapt its seed accordingly.

Moreover, adding the page parameter to the ->write_xxx() methods add some
consistency to the current API.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
CC: Josh Wu <josh.wu@atmel.com>
CC: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
CC: Maxime Ripard <maxime.ripard@free-electrons.com>
CC: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
CC: Huang Shijie <shijie.huang@arm.com>
CC: Stefan Agner <stefan@agner.ch>
CC: devel@driverdev.osuosl.org
CC: linux-arm-kernel@lists.infradead.org
CC: linux-kernel@vger.kernel.org
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-10-13 12:56:49 -07:00
Boris BREZILLON a7f5ba40c7 mtd: nand: remove unused ->init_size() hook
The ->init_size() hook was introduced to let NAND controller drivers
support NAND devices that could not be described in the nand_ids table.
Since then, the core has added support for extended-id parsing and
full-id description, thus allowing to describe pretty much all existing
NANDs.
Moreover, this hook is not used by any mainline driver, and should not be
used by new drivers, because detecting the NAND chip is not something
controller specific.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-10-01 10:20:15 -07:00
Boris BREZILLON 730a43fbc1 mtd: nand: add nand_check_erased helper functions
Add two helper functions to help NAND controller drivers test whether a
specific NAND region is erased or not.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-09-21 15:35:04 -07:00
Marek Vasut 61528d888a mtd: nand: Rename nand_chip .dn to .flash_node
Use a more descriptive name for the device_node element in struct nand_chip .
This name matches the element name used for device_node property of a flash
in the spi-nor framework.

Signed-off-by: Marek Vasut <marex@denx.de>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-09-11 15:48:43 -07:00
Brian Norris db5b09f6ed mtd: nand: correct indentation within conditional
We had an extra tab.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-05-22 10:57:47 -07:00
Brian Norris b74bdbe588 mtd: remove incorrect file name
This is an example of why it doesn't make much sense to put this
information here in the first place. I don't really know what purpose it
serves.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-05-22 10:57:46 -07:00
Brian Norris 5844feeaa4 mtd: nand: add common DT init code
These are already-documented common bindings for NAND chips. Let's
handle them in nand_base.

If NAND controller drivers need to act on this data before bringing up
the NAND chip (e.g., fill out ECC callback functions, change HW modes,
etc.), then they can do so between calling nand_scan_ident() and
nand_scan_tail().

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-05-11 16:22:29 -07:00
Richard Weinberger 0aec7ac997 mtd: nand: Remove in vain memset() in nand_onfi_get_features()
As all four bytes are written in any case the memset() is in vain.

Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-05-06 23:44:31 -07:00
Roger Quadros 60c70d66cd mtd: nand: Prevent possible kernel lockup in nand_command()
If a NAND device is not really present or pin muxes are not correctly
configured we can lock up the kernel waiting infinitely for NAND_STATUS
to be ready.

This can be easily reproduced on TI's DRA7-evm board by booting it
without NAND support in u-boot and disabling NAND pin muxes in the kernel.

Add timeout when waiting for NAND_CMD_RESET completion. As per ONFi v4.0
tRST can be upto 250ms for EZ-NAND and 5ms for raw NAND.

Signed-off-by: Roger Quadros <rogerq@ti.com>
Tested-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-03-30 17:39:15 -07:00
Brian Norris 73c8aaf436 mtd: nand: fix spelling of REPLACEABLE
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-03-24 14:21:27 -07:00
Brian Norris 0ec56dc4a1 mtd: nand: fully initialize mtd_oob_ops
We're not initializing the ooblen field. Our users don't care, since
they check that oobbuf == NULL first, but it's good practice to zero
unused fields out.

We can drop the NULL initializations since we're memset()ing the whole
thing.

Noticed by Coverity, CID #200821, #200822

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-03-11 15:21:48 -07:00
Brian Norris b1a2348a1a mtd: nand: fixup bounds checks for nand_{lock,unlock}()
Coverity noticed that these 'ret' assignments weren't being used. Let's
use them.

Note that nand_lock() and nand_unlock() are still not officially used by
any drivers.

Coverity CIDs #1227054 and #1227037

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-03-11 15:21:48 -07:00
Baruch Siach 2ea69d217a mtd: nand: remove redundant local variable
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-02-05 20:01:09 -08:00
Aaron Sierra e0377cdeba mtd: nand: Request strength instead of bytes for soft BCH
Previously, we requested that drivers pass ecc.size and ecc.bytes when
using NAND_ECC_SOFT_BCH. However, a driver is likely to only know the ECC
strength required for its NAND, so each driver would need to perform a
strength-to-bytes calculation.

Avoid duplicating this calculation in each driver by asking drivers to
pass ecc.size and ecc.strength so that the strength-to-bytes calculation
need only be implemented once.

This reverts/generalizes this commit:
    mtd: nand: Base BCH ECC bytes on required strength

Signed-off-by: Aaron Sierra <asierra@xes-inc.com>
Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-02-01 21:10:58 -08:00
Brian Norris 240181fd0f mtd: nand: default bitflip-reporting threshold to 75% of correction strength
The MTD API reports -EUCLEAN only if the maximum number of bitflips
found in any ECC block exceeds a certain threshold. This is done to
avoid excessive -EUCLEAN reports to MTD users, which may induce
additional scrubbing of data, even when the ECC algorithm in use is
perfectly capable of handling the bitflips.

This threshold can be controlled by user-space (via sysfs), to allow
users to determine what they are willing to tolerate in their
application. But it still helps to have sane defaults.

In recent discussion [1], it was pointed out that our default threshold
is equal to the correction strength. That means that we won't actually
report any -EUCLEAN (i.e., "bitflips were corrected") errors until there
are almost too many to handle. It was determined that 3/4 of the
correction strength is probably a better default.

[1] http://lists.infradead.org/pipermail/linux-mtd/2015-January/057259.html

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Acked-by: Huang Shijie <shijie.huang@intel.com>
2015-01-20 23:43:18 -08:00
Baruch Siach 57f5ef14a5 mtd: nand: remove duplicate comment line
Commit 7854d3f749 ("mtd: spelling, capitalization, uniformity") added
a correctly spelled line, but failed to remove the wrongly spelled one.
Commit 064a7694b5 ("mtd: Fix typo mtd/tests") then fixed the spelling
again, but left the duplication.

Fixes: 7854d3f749 ("mtd: spelling, capitalization, uniformity")
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-01-09 15:14:07 -08:00