Commit Graph

95 Commits

Author SHA1 Message Date
Brian Norris 9648388fc7 mtd: spi-nor: support lock/unlock for a few Winbond chips
These are recent Winbond models that are known to have lock/unlock
support via writing the Status Register, and that also support the TB
(Top/Bottom) protection bit.

Tested on w25q32dw.

[Note on style: these entries are getting pretty long lines, so I picked
a style that seems reasonable for splitting up the flags separate from
the other mostly-similar fields.]

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Reviewed-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Tested-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
2016-03-07 18:01:58 -08:00
Brian Norris 3dd8012a8e mtd: spi-nor: add TB (Top/Bottom) protect support
Some flash support a bit in the status register that inverts protection
so that it applies to the bottom of the flash, not the top. This yields
additions to the protection range table, as noted in the comments.

Because this feature is not universal to all flash that support
lock/unlock, control it via a new flag.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Tested-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
2016-03-07 18:01:57 -08:00
Brian Norris 76a4707de5 mtd: spi-nor: add SPI_NOR_HAS_LOCK flag
We can't determine this purely by manufacturer type (see commit
67b9bcd369 ("mtd: spi-nor: fix Spansion regressions (aliased with
Winbond)")), and it's not autodetectable by anything like SFDP. So make
a new flag for it.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Reviewed-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Tested-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
2016-03-07 18:01:57 -08:00
Brian Norris 0618114e2c mtd: spi-nor: use BIT() for flash_info flags
It's a little easier to read and make sure there are no collisions
(IMO).

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Reviewed-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Tested-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
2016-03-07 18:01:56 -08:00
Brian Norris 47b8edbf0d mtd: spi-nor: disallow further writes to SR if WP# is low
Locking the flash is most useful if it provides real hardware security.
Otherwise, it's little more than a software permission bit.

A reasonable use case that provides real HW security might be like
follows:

(1) hardware WP# is deasserted
(2) program flash
(3) flash range is protected via status register
(4) hardware WP# is asserted
(5) flash protection range can no longer be changed, until WP# is
    deasserted

In this way, flash protection is co-owned by hardware and software.

Now, one would expect to be able to perform step (3) with
ioctl(MEMLOCK), except that the spi-nor driver does not set the Status
Register Protect bit (a.k.a. Status Register Write Disable (SRWD)), so
even though the range is now locked, it does not satisfy step (5) -- it
can still be changed by a call to ioctl(MEMUNLOCK).

So, let's enable status register protection after the first lock
command, and disable protection only when the flash is fully unlocked.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Tested-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
2016-03-07 18:01:55 -08:00
Brian Norris f8860802da mtd: spi-nor: make lock/unlock bounds checks more obvious and robust
There are a few different corner cases to the current logic that seem
undesirable:

* mtd_lock() with offs==0 trips a bounds issue on
  ofs - mtd->erasesize < 0

* mtd_unlock() on the middle of a flash that is already unlocked will
  return -EINVAL

* probably other corner cases

So, let's stop doing "smart" checks like "check the block below us",
let's just do the following:

(a) pass only non-negative offsets/lengths to stm_is_locked_sr()
(b) add a similar stm_is_unlocked_sr() function, so we can check if the
    *entire* range is unlocked (and not just whether some part of it is
    unlocked)

Then armed with (b), we can make lock() and unlock() much more
symmetric:

(c) short-circuit the procedure if there is no work to be done, and
(d) check the entire range above/below

This also aligns well with the structure needed for proper TB
(Top/Bottom) support.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Tested-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
2016-03-07 18:01:54 -08:00
Brian Norris 4c0dba447e mtd: spi-nor: silently drop lock/unlock for already locked/unlocked region
If, for instance, the entire flash is already unlocked and I try to
mtd_unlock() the entire device, I don't expect to see an EINVAL error.
It should just silently succeed. Ditto for mtd_lock().

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Reviewed-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Tested-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
2016-03-07 18:01:54 -08:00
Brian Norris edf891ef9a mtd: spi-nor: wait for SR_WIP to clear on initial unlock
Fixup a piece leftover by commit 32321e950d ("mtd: spi-nor: wait until
lock/unlock operations are ready"). That commit made us wait for the WIP
bit to settle after lock/unlock operations, but it missed the open-coded
"unlock" that happens at probe() time.

We should probably have this code utilize the unlock() routines in the
future, to avoid duplication, but unfortunately, flash which need to be
unlocked don't all have a proper ->flash_unlock() callback.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Cc: Stas Sergeev <stsp@users.sourceforge.net>
Reviewed-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Tested-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
2016-03-07 18:01:50 -08:00
Ezequiel García 4607777c71 mtd: spi-nor: add subsector flag to n25q128a
Micron n25q128axx support subsector (4K) erase so let's update the flags.
Tested on n25q128a13.

Signed-off-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2016-03-04 19:30:38 -08:00
Cyrille Pitchen 3b5394a3cc mtd: spi-nor: remove micron_quad_enable()
This patch remove the micron_quad_enable() function which force the Quad
SPI mode. However, once this mode is enabled, the Micron memory expect ALL
commands to use the SPI 4-4-4 protocol. Hence a failure does occur when
calling spi_nor_wait_till_ready() right after the update of the Enhanced
Volatile Configuration Register (EVCR) in the micron_quad_enable() as
the SPI controller driver is not aware about the protocol change.

Since there is almost no performance increase using Fast Read 4-4-4
commands instead of Fast Read 1-1-4 commands, we rather keep on using the
Extended SPI mode than enabling the Quad SPI mode.

Let's take the example of the pretty standard use of 8 dummy cycles during
Fast Read operations on 64KB erase sectors:

Fast Read 1-1-4 requires 8 cycles for the command, then 24 cycles for the
3byte address followed by 8 dummy clock cycles and finally 65536*2 cycles
for the read data; so 131112 clock cycles.

On the other hand the Fast Read 4-4-4 would require 2 cycles for the
command, then 6 cycles for the 3byte address followed by 8 dummy clock
cycles and finally 65536*2 cycles for the read data. So 131088 clock
cycles. The theorical bandwidth increase is 0.0%.

Now using Fast Read operations on 512byte pages:
Fast Read 1-1-4 needs 8+24+8+(512*2) = 1064 clock cycles whereas Fast
Read 4-4-4 would requires 2+6+8+(512*2) = 1040 clock cycles. Hence the
theorical bandwidth increase is 2.3%.
Consecutive reads for non sequential pages is not a relevant use case so
The Quad SPI mode is not worth it.

mtd_speedtest seems to confirm these figures.

Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com>
Fixes: 548cd3ab54 ("mtd: spi-nor: Add quad I/O support for Micron SPI NOR")
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2016-02-12 11:35:13 -08:00
Sascha Hauer c082667949 mtd: spi-nor: Add support for s25fl116k
The Spansion s25fl116k is a 16MBit NOR Flash supporting dual and
quad read operations.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2016-02-12 11:34:01 -08:00
Ezequiel García 32321e950d mtd: spi-nor: wait until lock/unlock operations are ready
On Micron and Numonyx devices, the status register write command
(WRSR), raises a work-in-progress bit (WIP) on the status register.
The datasheets for these devices specify that while the status
register write is in progress, the status register WIP bit can still
be read to check the end of the operation.

This commit adds a wait_till_ready call on lock/unlock operations,
which is required for Micron and Numonyx but should be harmless for
others. This is needed to prevent applications from issuing erase or
program operations before the unlock operation is completed.

Reported-by: Stas Sergeev <stsp@list.ru>
Signed-off-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2016-01-06 17:18:34 -08:00
Brian Norris e576330033 mtd: merge MTD development from v4.4 into for-v4.5 development
Small conflict between some bugfixes for 4.4 and some refactoring for
4.5.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2016-01-05 16:05:56 -08:00
Brian Norris a32d5b726f mtd: spi-nor: fix stm_is_locked_sr() parameters
stm_is_locked_sr() takes the status register (SR) value as the last
parameter, not the second.

Reported-by: Bayi Cheng <bayi.cheng@mediatek.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Cc: Bayi Cheng <bayi.cheng@mediatek.com>
2016-01-05 16:00:41 -08:00
Brian Norris 67b9bcd369 mtd: spi-nor: fix Spansion regressions (aliased with Winbond)
Spansion and Winbond have occasionally used the same manufacturer ID,
and they don't support the same features. Particularly, writing SR=0
seems to break read access for Spansion's s25fl064k. Unfortunately, we
don't currently have a way to differentiate these Spansion and Winbond
parts, so rather than regressing support for these Spansion flash, let's
drop the new Winbond lock/unlock support for now. We can try to address
Winbond support during the next release cycle.

Original discussion:

http://patchwork.ozlabs.org/patch/549173/
http://patchwork.ozlabs.org/patch/553683/

Fixes: 357ca38d47 ("mtd: spi-nor: support lock/unlock/is_locked for Winbond")
Fixes: c6fc2171b2 ("mtd: spi-nor: disable protection for Winbond flash at startup")
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Reported-by: Felix Fietkau <nbd@openwrt.org>
Cc: Felix Fietkau <nbd@openwrt.org>
2016-01-05 16:00:03 -08:00
Fabio Estevam f49289ce64 mtd: spi-nor: Check the return value from read_sr()
We should better check the return value from read_sr() and
propagate it in the case of error.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-12-09 18:15:01 -08:00
Heiner Kallweit d6af26944a mtd: spi-nor: fix error handling in spi_nor_erase
The documenting comment of mtd_erase in mtdcore.c states:
Device drivers are supposed to call instr->callback() whenever
the operation completes, even if it completes with a failure.

Currently the callback isn't called in case of failure. Fix this.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-12-04 15:38:47 -08:00
Ricardo Ribalda 9b9f1033da mtd: spi-nor: Fix error message with unrecognized JEDEC
The error message was:

m25p80 spi32766.0: unrecognized JEDEC id bytes: 00,  0,  0

The new error message:

m25p80 spi32766.0: unrecognized JEDEC id bytes: 00, 00, 00

Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-12-01 10:39:49 -08:00
Andreas Fenkart 0501f2e5ff mtd: spi-nor: mx25l3205d/mx25l6405d: append SECT_4K
according datasheet both chips can erase 4kByte sectors individually

Signed-off-by: Andreas Fenkart <andreas.fenkart@dev.digitalstrom.org>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-11-19 13:37:35 -08:00
Brian Norris c67cbb839d mtd: spi-nor: provide default erase_sector implementation
Some spi-nor drivers perform sector erase by duplicating their
write_reg() command. Let's not require that the driver fill this out,
and provide a default instead.

Tested on m25p80.c and Medatek's MT8173 SPI NOR flash driver.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-11-19 13:34:44 -08:00
Brian Norris 20625dfe03 mtd: spi-nor: remove unnecessary leading space from dbg print
As Cyrille noted [1], this line is wrong.

[1] http://lists.infradead.org/pipermail/linux-mtd/2015-September/061725.html

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Cc: Cyrille Pitchen <cyrille.pitchen@atmel.com>
2015-11-16 15:12:30 -08:00
Brian Norris 30069af734 mtd: spi-nor: drop flash_node field
We can just alias to the MTD of_node.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com>
2015-11-11 13:58:56 -08:00
Brian Norris 9c7d787508 mtd: spi-nor: convert to spi_nor_{get, set}_flash_node()
Used semantic patch with 'make coccicheck MODE=patch COCCI=script.cocci':

---8<----
virtual patch

@@
struct spi_nor b;
struct spi_nor *c;
expression d;
@@
(
-(b).flash_node = (d)
+spi_nor_set_flash_node(&b, d)
|
-(c)->flash_node = (d)
+spi_nor_set_flash_node(c, d)
)
---8<----

And a manual conversion for the one use of spi_nor_get_flash_node().

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com>
2015-11-11 13:45:24 -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
Brian Norris a23eb34198 mtd: spi-nor: add DUAL_READ for w25q{32,64}dw
These flash support dual and quad read. Tested dual read on the 32 Mbit
version.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-10-19 09:50:44 -07:00
Brian Norris c6fc2171b2 mtd: spi-nor: disable protection for Winbond flash at startup
In case the flash was locked at boot time.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-10-13 18:22:56 -07:00
Brian Norris 357ca38d47 mtd: spi-nor: support lock/unlock/is_locked for Winbond
Many other flash share the same features as ST Micro. I've tested some
Winbond flash, so add them.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-10-13 18:22:55 -07:00
Brian Norris 5bf0e69b67 mtd: spi-nor: add mtd_is_locked() support
This enables ioctl(MEMISLOCKED). Status can now be reported in the
mtdinfo or flash_lock utilities found in mtd-utils.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-10-13 18:22:54 -07:00
Brian Norris 62593cf40b mtd: spi-nor: refactor block protection functions
This code was a bit sloppy, would produce a lot of copy-and-paste, and
did not always provide a sensible interface:

 * It didn't validate the length for LOCK and the offset for UNLOCK, so
   we were essentially discarding half of the user-supplied data and
   assuming what they wanted to lock/unlock
 * It didn't do very good error checking
 * It didn't make use of the fact that this operation works on
   power-of-two dimensions

So, rewrite this to do proper bit arithmetic rather than a bunch of
hard-coded condition tables. Now we have:

 * More comments on how this was derived
 * Notes on what is (and isn't) supported
 * A more exendible function, so we could add support for other
   protection ranges
 * More accurate locking - e.g., suppose the top quadrant is locked (75%
   to 100%); then in the following cases, case (a) will succeed but (b)
   will not (return -EINVAL):
     (a) user requests lock 3rd quadrant (50% to 75%)
     (b) user requests lock 3rd quadrant, minus a few blocks (e.g., 50%
         to 73%)
   Case (b) *should* fail, since we'd have to lock blocks that weren't
   requested. But the old implementation didn't know the difference and
   would lock the entire second half (50% to 100%)

This refactoring work will also help enable the addition of
mtd_is_locked() support and potentially the support of bottom boot
protection (TB=1).

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-10-13 18:22:54 -07:00
Brian Norris f0d2448e9a mtd: spi-nor: use SNOR_MFR_* instead of CFI_MFR_*
No functional change, just cosmetic.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-10-13 18:22:52 -07:00
Sean Nyekjaer 7c748f5774 mtd: spi-nor: Add support for s25fl004k
Signed-off-by: Sean Nyekjaer <sean.nyekjaer@prevas.dk>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-10-13 12:56:50 -07:00
Sean Nyekjaer aada20cd2b mtd: spi-nor: s25fl204k supports dual I/0
Signed-off-by: Sean Nyekjaer <sean.nyekjaer@prevas.dk>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-10-13 12:56:50 -07:00
Aurelien Chanot f9bcb6dc80 mtd: spi-nor: Add support for Micron n25q032a
The N25Q032A is identical to the N25Q032 except it has a different
supply voltage range. Therefore, it has a new JEDEC ID.

Signed-off-by: Aurelien Chanot <chanot.a@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-10-12 18:37:10 -07:00
Brian Norris 4404bd742d mtd: spi-nor: add support for w25q128fw
Tested only with single I/O, but the datasheet says it supports dual and
quad.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-09-29 13:25:12 -07:00
Furquan Shaikh 09b6a37768 mtd: spi-nor: scale up timeout for full-chip erase
This patch fixes timeout issues seen on large NOR flash (e.g., 16MB
w25q128fw) when using ioctl(MEMERASE) with offset=0 and length=16M. The
input parameters matter because spi_nor_erase() uses a different code
path for full-chip erase, where we use the SPINOR_OP_CHIP_ERASE (0xc7)
opcode.

Fix: use a different timeout for full-chip erase than for other
commands.

While most operations can be expected to perform relatively similarly
across a variety of NOR flash types and sizes (and therefore might as
well use a similar timeout to keep things simple), full-chip erase is
unique, because the time it typically takes to complete:
(1) is much larger than most operations and
(2) scales with the size of the flash.

Let's base our timeout on the original comments stuck here -- that a 2MB
flash requires max 40s to erase.

Small survey of a few flash datasheets I have lying around:

  Chip         Size (MB)   Max chip erase (seconds)
  ----         --------    ------------------------
  w25q32fw     4           50
  w25q64cv     8           30
  w25q64fw     8           100
  w25q128fw    16          200
  s25fl128s    16          ~256
  s25fl256s    32          ~512

From this data, it seems plenty sufficient to say we need to wait for
40 seconds for each 2MB of flash.

After this change, it might make some sense to decrease the timeout for
everything else, as even the most extreme operations (single block
erase?) shouldn't take more than a handful of seconds. But for safety,
let's leave it as-is. It's only an error case, after all, so we don't
exactly need to optimize it.

Signed-off-by: Furquan Shaikh <furquan@google.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-09-29 13:25:09 -07:00
Yao Yuan c887be71cc mtd: spi-nor: Add support for sst25wf040b
It is a 512KiB flash with 4 KiB erase sectors.

Signed-off-by: Yuan Yao <yao.yuan@freescale.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-09-29 13:17:23 -07:00
Joachim Eastwood adf508c347 mtd: spi-nor: s25fl008k and s25fl016k supports dual/quad mode
s25fl016k can be found on Embedded Artists' LPC4357 Developer's Kit
where is used in quad mode by the LPC4357 SPIFI controller.

Signed-off-by: Joachim Eastwood <manabian@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-09-28 17:59:57 -07:00
Jagan Teki f9f3ce835d mtd: spi-nor: Zap unneeded write_enable from write_reg
The 'write_enable' argument is unused and unneeded, so remove it from
the API.

Signed-off-by: Jagan Teki <jteki@openedev.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Han Xu <han.xu@freescale.com>
[Brian: fixed for nxp-spifi.c]
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-09-11 16:04:55 -07:00
Jagan Teki fd7252346b mtd: spi-nor: Use write_sr for write status
Use existing write_sr() call instead of decoding and
calling nor->write_reg separately.

Signed-off-by: Jagan Teki <jteki@openedev.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-09-11 15:53:48 -07:00
Marek Vasut 11bff0b70c mtd: spi-nor: Decouple SPI NOR's device_node from controller device
The problem this patch is trying to address is such, that SPI NOR flash
devices attached to a dedicated SPI NOR controller cannot read their
properties from the associated struct device_node.

A couple of facts first:
1) Each SPI NOR flash has a struct spi_nor associated with it.
2) Each SPI NOR flash has certain device properties associated
   with it, for example the OF property 'm25p,fast-read' is a
   good pick. These properties are used by the SPI NOR core to
   select which opcodes are sent to such SPI NOR flash. These
   properties are coming from spi_nor .dev->of_node .

The problem is, that for SPI NOR controllers, the struct spi_nor .dev
element points to the struct device of the SPI NOR controller, not the
SPI NOR flash. Therefore, the associated dev->of_node also is the
one of the controller and therefore the SPI NOR core code is trying to
parse the SPI NOR controller's properties, not the properties of the
SPI NOR flash.

Note: The m25p80 driver is not affected, because the controller and
      the flash are the same device, so the associated device_node
      of the controller and the flash are the same.

This patch adjusts the SPI NOR core such that the device_node is not
picked from spi_nor .dev directly, but from a new separate spi_nor
.flash_node element. This let's the SPI NOR controller drivers set up
a different spi_nor .flash_node element for each SPI NOR flash.

This patch also fixes the controller drivers to be compatible with
this modification and correctly set the spi_nor .flash_node element.

This patch is inspired by 5844feeaa4
mtd: nand: add common DT init code

Signed-off-by: Marek Vasut <marex@denx.de>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-09-11 15:48:21 -07:00
Brian Norris f9b97fe614 Merge MTD 4.3-rc1 updates into -next 2015-09-09 16:57:39 -07:00
Brian Norris 2ff46e6fea mtd: spi-nor: fix NULL dereference when no match found in spi_nor_ids[]
Commit 06bb6f5a69 ("mtd: spi-nor: stop (ab)using struct
spi_device_id") converted an array into a pointer, which means that
we should be checking if the pointer goes anywhere, not whether the C
string is empty. To do the latter means we dereference a NULL pointer
when we reach the terminating entry, for which 'name' is now NULL
instead of an array { 0, 0, ... }.

Sample crash:

[    1.101371] Unable to handle kernel NULL pointer dereference at virtual address 00000000
[    1.109457] pgd = c0004000
[    1.112157] [00000000] *pgd=00000000
[    1.115736] Internal error: Oops: 5 [#1] SMP ARM
[    1.120345] Modules linked in:
[    1.123405] CPU: 3 PID: 1 Comm: swapper/0 Not tainted 4.2.0-next-20150902+ #61
[    1.130611] Hardware name: Rockchip (Device Tree)
[    1.135306] task: ee0b8d40 ti: ee0ba000 task.ti: ee0ba000
[    1.140697] PC is at spi_nor_scan+0x90/0x8c4
[    1.144958] LR is at spi_nor_scan+0xa4/0x8c4
...
[    1.504112] [<c03cc2e0>] (spi_nor_scan) from [<c03cb188>] (m25p_probe+0xc8/0x11c)
[    1.511583] [<c03cb188>] (m25p_probe) from [<c03cd9d8>] (spi_drv_probe+0x60/0x7c)
[    1.519055] [<c03cd9d8>] (spi_drv_probe) from [<c037faa0>] (driver_probe_device+0x1a0/0x444)
[    1.527478] [<c037faa0>] (driver_probe_device) from [<c037fec8>] (__device_attach_driver+0x94/0xa0)
[    1.536507] [<c037fec8>] (__device_attach_driver) from [<c037db3c>] (bus_for_each_drv+0x94/0xa4)
[    1.545277] [<c037db3c>] (bus_for_each_drv) from [<c037f7e4>] (__device_attach+0xa4/0x144)
[    1.553526] [<c037f7e4>] (__device_attach) from [<c0380058>] (device_initial_probe+0x1c/0x20)
[    1.562035] [<c0380058>] (device_initial_probe) from [<c037ec88>] (bus_probe_device+0x38/0x94)
[    1.570631] [<c037ec88>] (bus_probe_device) from [<c037ccf4>] (device_add+0x430/0x558)
[    1.578534] [<c037ccf4>] (device_add) from [<c03d0240>] (spi_add_device+0xe4/0x174)
[    1.586178] [<c03d0240>] (spi_add_device) from [<c03d0a24>] (spi_register_master+0x698/0x7d4)
[    1.594688] [<c03d0a24>] (spi_register_master) from [<c03d0ba0>] (devm_spi_register_master+0x40/0x7c)
[    1.603892] [<c03d0ba0>] (devm_spi_register_master) from [<c03d2fb4>] (rockchip_spi_probe+0x360/0x3f4)
[    1.613182] [<c03d2fb4>] (rockchip_spi_probe) from [<c0381e34>] (platform_drv_probe+0x58/0xa8)
[    1.621779] [<c0381e34>] (platform_drv_probe) from [<c037faa0>] (driver_probe_device+0x1a0/0x444)
[    1.630635] [<c037faa0>] (driver_probe_device) from [<c037fdc4>] (__driver_attach+0x80/0xa4)
[    1.639058] [<c037fdc4>] (__driver_attach) from [<c037e850>] (bus_for_each_dev+0x98/0xac)
[    1.647221] [<c037e850>] (bus_for_each_dev) from [<c037f448>] (driver_attach+0x28/0x30)
[    1.655210] [<c037f448>] (driver_attach) from [<c037ef74>] (bus_add_driver+0x128/0x250)
[    1.663200] [<c037ef74>] (bus_add_driver) from [<c0380c40>] (driver_register+0xac/0xf0)
[    1.671191] [<c0380c40>] (driver_register) from [<c0381d50>] (__platform_driver_register+0x58/0x6c)
[    1.680221] [<c0381d50>] (__platform_driver_register) from [<c0a467c8>] (rockchip_spi_driver_init+0x18/0x20)
[    1.690033] [<c0a467c8>] (rockchip_spi_driver_init) from [<c00098a4>] (do_one_initcall+0x124/0x1dc)
[    1.699063] [<c00098a4>] (do_one_initcall) from [<c0a19f84>] (kernel_init_freeable+0x218/0x2ec)
[    1.707748] [<c0a19f84>] (kernel_init_freeable) from [<c0719ed8>] (kernel_init+0x1c/0xf4)
[    1.715912] [<c0719ed8>] (kernel_init) from [<c000fe50>] (ret_from_fork+0x14/0x24)
[    1.723460] Code: e3510000 159f67c0 0a00000c e5961000 (e5d13000)
[    1.729564] ---[ end trace 95baa6b3b861ce25 ]---

Fixes: 06bb6f5a69 ("mtd: spi-nor: stop (ab)using struct spi_device_id")
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Cc: Rafał Miłecki <zajec5@gmail.com>
2015-09-02 16:34:35 -07:00
Brian Norris 1976367173 mtd: spi-nor: embed struct mtd_info within struct spi_nor
This reflects the proper layering, so let's do it.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Tested-by: Joachim Eastwood <manabian@gmail.com>
2015-09-02 14:11:40 -07:00
Brian Norris c9ec3900ab mtd: spi-nor: assign mtd->priv in spi_nor_scan()
Layering suggests that the SPI NOR layer (not the hardware driver)
should be initializing the MTD layer.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Tested-by: Joachim Eastwood <manabian@gmail.com>
2015-09-02 14:11:40 -07:00
Joachim Eastwood 0f12a27b47 mtd: spi-nor: s25sl064p supports both dual and quad I/O
This chip can be found on Hitex LPC4350 Evaluation Board.

Signed-off-by: Joachim Eastwood <manabian@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-09-02 14:09:56 -07:00
Jonas Gorski c175208679 mtd: spi-nor: allow dual/quad reads on S25FL129P
According to the datasheet[1], both S25FL129P0 (256kB sectors) and
S25FL129P1 (64kB sectors) support dual read, quad read, dual i/o read
and quad i/o read.

I have verified dual read to be working for S25FL129P1 on a dual
capable spi controller. Quad as well as S25FL129P0 is untested, lacking
hardware to verify.

[1] http://www.spansion.com/Support/Datasheets/S25FL129P_00.pdf

Signed-off-by: Jonas Gorski <jogo@openwrt.org>
Reviewed-by: Marek Vasut <marex@denx.de>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-09-02 14:07:53 -07:00
Alexis Ballier a1d97ef96e mtd: spi-nor: Add support for sst25wf020a
It is a 256KiB flash with 4 KiB erase sectors
and 64KiB overlay blocks.

This is the one available on Hardkernel's Odroid U3 shield.

Signed-off-by: Alexis Ballier <aballier@gentoo.org>
[Brian: seems like this does NOT require the usual SST_WRITE hacks]
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-09-02 13:57:05 -07:00
Mika Westerberg 2a06c7b1fd mtd: spi-nor: Add support for Micron n25q064a serial flash
Add Micron (n25q064a) 8MB flash to the list of supported chips.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Jagan Teki <jteki@openedev.com>
[Brian: fixup context]
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-09-02 13:56:24 -07:00
Rafał Miłecki 06bb6f5a69 mtd: spi-nor: stop (ab)using struct spi_device_id
Using struct spi_device_id for storing list of flash devices comes from
early SPI NOR framework days. Thanks to the commit 70f3ce0510 ("mtd:
spi-nor: make spi_nor_scan() take a chip type name, not spi_device_id")
we can stop using spi_device_id and just switch to our own struct.

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-08-25 13:42:21 -07:00
Antony Pavlov b4d97f022a mtd: spi-nor: add Spansion S25FL204K support
Spansion S25FL204K is a 4-Mbit 3.0V Serial Flash Memory
with Uniform 4 kB Sectors.

Signed-off-by: Antony Pavlov <antonynpavlov@gmail.com>
Acked-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-08-14 11:22:56 -07:00