Commit Graph

62 Commits

Author SHA1 Message Date
Michael Walle 0257be79fc mtd: spi-nor: expose internal parameters via debugfs
There is no way to gather all information to verify support for a new
flash chip. Also if you want to convert an existing flash chip to the
new SFDP parsing, there is not enough information to determine if the
flash will work like before. To ease this development, expose internal
parameters via the debugfs.

Signed-off-by: Michael Walle <michael@walle.cc>
Signed-off-by: Pratyush Yadav <p.yadav@ti.com>
Reviewed-by: Pratyush Yadav <p.yadav@ti.com>
Link: https://lore.kernel.org/r/20220429102018.2361038-2-michael@walle.cc
2022-05-09 16:55:22 +05:30
Michael Walle d92e0dbc6a mtd: spi-nor: export spi_nor_hwcaps_pp2cmd()
The function will also be used by the debugfs module.

Signed-off-by: Michael Walle <michael@walle.cc>
Signed-off-by: Pratyush Yadav <p.yadav@ti.com>
Reviewed-by: Pratyush Yadav <p.yadav@ti.com>
Link: https://lore.kernel.org/r/20220429102018.2361038-1-michael@walle.cc
2022-05-09 16:55:22 +05:30
Michael Walle 94f697c538 mtd: spi-nor: move spi_nor_write_ear() to winbond module
The "Extended Address Register" is winbond specific. If the flash is
larger than 16MiB and is used in 3 byte address mode, it is used to set
the remaining address bits. Move the write_ear() function, the opcode
macros and the spimem op template into the winbond module and rename
them accordingly.

Signed-off-by: Michael Walle <michael@walle.cc>
Signed-off-by: Pratyush Yadav <p.yadav@ti.com>
Reviewed-by: Pratyush Yadav <p.yadav@ti.com>
Link: https://lore.kernel.org/r/20220429100153.2338501-1-michael@walle.cc
2022-05-02 14:42:00 +05:30
Michael Walle 5ad784d990 mtd: spi-nor: amend the rdsr dummy cycles documentation
The rdsr dummy cycles are only used by the 8d-8d-8d mode. Mention that
in the documentation.

Signed-off-by: Michael Walle <michael@walle.cc>
Signed-off-by: Pratyush Yadav <p.yadav@ti.com>
Reviewed-by: Pratyush Yadav <p.yadav@ti.com>
Link: https://lore.kernel.org/r/20220418112837.2792242-1-michael@walle.cc
2022-04-29 11:32:12 +05:30
Tudor Ambarus c0abb861c5 mtd: spi-nor: Introduce templates for SPI NOR operations
Clean the op declaration and hide the details of each op. With this it
results a cleanner, easier to read code. No functional change expected.

Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Signed-off-by: Pratyush Yadav <p.yadav@ti.com>
Acked-by: Michael Walle <michael@walle.cc>
Acked-by: Pratyush Yadav <p.yadav@ti.com>
Link: https://lore.kernel.org/r/20220420103427.47867-10-tudor.ambarus@microchip.com
2022-04-27 14:57:36 +05:30
Tudor Ambarus a604ab33cb mtd: spi-nor: core: Add helpers to read/write any register
There are manufacturers that use registers indexed by address. Some of
them support "read/write any register" opcodes. Provide core methods that
can be used by all manufacturers. SPI NOR controller ops are intentionally
not supported as we intend to move all the SPI NOR controller drivers
under the SPI subsystem.

Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Signed-off-by: Pratyush Yadav <p.yadav@ti.com>
Tested-by: Takahiro Kuwano <Takahiro.Kuwano@infineon.com>
Reviewed-by: Pratyush Yadav <p.yadav@ti.com>
Reviewed-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20220420103427.47867-7-tudor.ambarus@microchip.com
2022-04-27 14:57:36 +05:30
Tudor Ambarus 86b6b55ffb mtd: spi-nor: core: Introduce method for RDID op
RDID is used in the core to auto detect the flash, but also by some
manufacturer drivers that contain flashes that support Octal DTR mode,
so that they can read the flash ID after the switch to Octal DTR was made
to test if the switch was successful. Introduce a core method for RDID op
to avoid code duplication.

Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Signed-off-by: Pratyush Yadav <p.yadav@ti.com>
Reviewed-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20220420103427.47867-5-tudor.ambarus@microchip.com
2022-04-27 14:57:35 +05:30
Michael Walle 3c552889e4 mtd: spi-nor: renumber flags
As we have deleted some flag, lets renumber them so there are no holes.

Signed-off-by: Michael Walle <michael@walle.cc>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Pratyush Yadav <p.yadav@ti.com>
Link: https://lore.kernel.org/r/20220223134358.1914798-33-michael@walle.cc
2022-02-25 18:13:20 +02:00
Michael Walle 51c55506a7 mtd: spi-nor: spansion: convert USE_CLSR to a manufacturer flag
Now that all functions using that flag are local to the spansion module,
we can convert the flag to a manufacturer one.

Signed-off-by: Michael Walle <michael@walle.cc>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Tested-by: Pratyush Yadav <p.yadav@ti.com> # on mt35xu512aba, s28hs512t
Reviewed-by: Pratyush Yadav <p.yadav@ti.com>
Link: https://lore.kernel.org/r/20220223134358.1914798-30-michael@walle.cc
2022-02-25 18:12:56 +02:00
Michael Walle 8f938262a6 mtd: spi-nor: micron-st: convert USE_FSR to a manufacturer flag
Now that all functions using that flag are local to the micron module,
we can convert the flag to a manufacturer one.

Signed-off-by: Michael Walle <michael@walle.cc>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Tested-by: Pratyush Yadav <p.yadav@ti.com> # on mt35xu512aba, s28hs512t
Reviewed-by: Pratyush Yadav <p.yadav@ti.com>
Link: https://lore.kernel.org/r/20220223134358.1914798-26-michael@walle.cc
2022-02-25 18:12:28 +02:00
Michael Walle 8b4195cd6d mtd: spi-nor: move all xilinx specifics into xilinx.c
Mechanically move all the xilinx functions to its own module.

Then register the new flash specific ready() function.

Signed-off-by: Michael Walle <michael@walle.cc>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Pratyush Yadav <p.yadav@ti.com>
Link: https://lore.kernel.org/r/20220223134358.1914798-22-michael@walle.cc
2022-02-25 18:12:01 +02:00
Michael Walle 9fb4beb1b0 mtd: spi-nor: guard _page_size parameter in S3AN_INFO()
The _page_size marco parameter was missing parentheses around it. Add
them.

Signed-off-by: Michael Walle <michael@walle.cc>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Pratyush Yadav <p.yadav@ti.com>
Link: https://lore.kernel.org/r/20220223134358.1914798-21-michael@walle.cc
2022-02-25 18:11:54 +02:00
Michael Walle 66cf87c600 mtd: spi-nor: export more functions to be used in vendor modules
We will move vendor specific code into the vendor modules and thus we
will have to export these functions so they can be called.

Signed-off-by: Michael Walle <michael@walle.cc>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Pratyush Yadav <p.yadav@ti.com>
Link: https://lore.kernel.org/r/20220223134358.1914798-20-michael@walle.cc
2022-02-25 18:11:23 +02:00
Michael Walle 4cf1c7bdc5 mtd: spi-nor: allow a flash to define its own ready() function
Xilinx and Micron flashes have their own implementation of the
spi_nor_ready() function. At the moment, the core will figure out
which one to call according to some flags. Lay the foundation to
make it possible that a flash can register its own ready()
function.

Signed-off-by: Michael Walle <michael@walle.cc>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Pratyush Yadav <p.yadav@ti.com>
Link: https://lore.kernel.org/r/20220223134358.1914798-19-michael@walle.cc
2022-02-25 18:11:17 +02:00
Michael Walle b44aa9ac6b mtd: spi-nor: slightly refactor the spi_nor_setup()
Instead of always using a function pointer (and initializing it to our
default), just call the default function if the flash didn't set its own
one. That will make the call flow easier to follow.

Also mark the parameter as optional now.

Signed-off-by: Michael Walle <michael@walle.cc>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Pratyush Yadav <p.yadav@ti.com>
Link: https://lore.kernel.org/r/20220223134358.1914798-18-michael@walle.cc
2022-02-25 18:11:11 +02:00
Tudor Ambarus ec1c0e9960 mtd: spi-nor: Rework the flash_info flags
Clarify for what the flash_info flags are used for. Split them in
four categories and a bool:
1/ FLAGS: flags that indicate support that is not defined by the JESD216
   standard in its SFDP tables.
2/ NO_SFDP_FLAGS: these flags are used when the flash does not define the
   SFDP tables. These flags indicate support that can be discovered via
   SFDP. Used together with SPI_NOR_SKIP_SFDP flag.
3/ FIXUP_FLAGS: flags that indicate support that can be discovered
   via SFDP ideally, but can not be discovered for this particular flash
   because the SFDP table that indicates this support is not defined by
   the flash. In case the table for this support is defined but has wrong
   values, one should instead use a post_sfdp() hook to set the SNOR_F
   equivalent flag.
4/ MFR_FLAGS: manufacturer private flags. Used in the manufacturer
   fixup hooks to differentiate support between flashes of the same
   manufacturer.
5/ PARSE_SFDP: sets info->parse_sfdp to true. All flash_info entries
   that support SFDP should be converted to set info->parse_sfdp to true.

SPI NOR flashes that statically declare one of the
SPI_NOR_{DUAL, QUAD, OCTAL, OCTAL_DTR}_READ flags and do not support
the RDSFDP command are gratuiously receiving the RDSFDP command
in the attempt of parsing the SFDP tables. It is not desirable to issue
commands that are not supported, so introduce PARSE_SFDP to help on this
situation.

New flash additions/updates should be declared/updated to use either
PARSE_SFDP or SPI_NOR_SKIP_SFDP.  Once all the flash_info entries are
converted to use SPI_NOR_SKIP_SFDP or PARSE_SFDP, we can get rid of the
SPI_NOR_SKIP_SFDP flag and use just the bool nor->info->parse_sfdp to
determine whether to parse SFDP or not. SPI_NOR_SKIP_SFDP flag is kept
just as a way to differentiate whether a flash is converted to the new
flags logic or not.
Support that can be discovered when parsing SFDP should not be duplicated
by explicit flags at flash declaration. All the flash parameters will be
discovered when parsing SFDP. Sometimes manufacturers wrongly define some
fields in the SFDP tables. If that's the case, SFDP data can be amended
with the fixups() hooks. It is not common, but if the SFDP tables are
entirely wrong, and it does not worth the hassle to tweak the SFDP
parameters by using the fixups hooks, or if the flash does not define the
SFDP tables at all, then statically init the flash with the
SPI_NOR_SKIP_SFDP flag and specify the rest of flash capabilities with
the flash info flags.

With time, we want to convert all flashes to use PARSE_SFDP and
stop triggering the SFDP parsing with the
SPI_NOR_{DUAL, QUAD, OCTAL*}_READ flags. Getting rid of the
SPI_NOR_{OCTAL, OCTAL_DTR}_READ trigger is easily achievable,
the rest are a long term goal.

Manufacturer specific flags like USE_CLSR, USE_FSR, SPI_NOR_XSR_RDY,
will be removed in a future series.

No functional changes intended in this patch.

Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Pratyush Yadav <p.yadav@ti.com>
Link: https://lore.kernel.org/r/20211207140254.87681-7-tudor.ambarus@microchip.com
2021-12-07 17:05:11 +02:00
Tudor Ambarus 7683b39d60 mtd: spi-nor: core: Introduce flash_info mfr_flags
Used in the manufacturer fixup hooks to differentiate support
between flashes of the same manufacturer. Not used in the
SPI NOR core.

Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Michael Walle <michael@walle.cc>
Reviewed-by: Pratyush Yadav <p.yadav@ti.com>
Link: https://lore.kernel.org/r/20211207140254.87681-6-tudor.ambarus@microchip.com
2021-12-07 17:05:10 +02:00
Tudor Ambarus ff67592cbd mtd: spi-nor: Introduce spi_nor_set_mtd_info()
Used to init all the mtd_info fields. Move the mtd_info init
the last thing in the spi_nor_scan(), so that we avoid superfluous
initialization of the mtd_info fields in case of errors.

While here use common naming scheme for functions that are setting
mtd_info fields:
s/spi_nor_register_locking_ops/spi_nor_set_mtd_locking_ops
s/spi_nor_otp_init/spi_nor_set_mtd_otp_ops
The functions names are self explanatory, get rid of the comment
for the OTP function.

Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Michael Walle <michael@walle.cc>
Reviewed-by: Pratyush Yadav <p.yadav@ti.com>
Link: https://lore.kernel.org/r/20211207140254.87681-4-tudor.ambarus@microchip.com
2021-12-07 17:05:10 +02:00
Tudor Ambarus dacc8cfee4 mtd: spi-nor: core: Introduce the late_init() hook
Flash parameters init is done in a spaghetti way right now.
There is the init based on the flash_info data, then there is the
default_init() hook, then SFDP init, an intermediary post_bft(),
then post_sfdp() and a spi_nor_late_init_params(). Each method can
overwrite previuosly initialized parameters.

We want to separate what is SFDP and non-SFDP specific. late_init()
will replace the default_init() hook and will be used only to initialize
flash parameters that are not declared in the JESD216 SFDP standard, or
where SFDP tables are not defined at all.
We cut a member in the chain of initializing parameters by getting rid
of the default_init() hook, and we make it clear that everything that is
in late_init() is not covered by the SFDP tables defined by the flash.

Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Michael Walle <michael@walle.cc>
Reviewed-by: Pratyush Yadav <p.yadav@ti.com>
Link: https://lore.kernel.org/r/20211029172633.886453-6-tudor.ambarus@microchip.com
2021-11-17 14:41:28 +02:00
Tudor Ambarus 7158c86e56 mtd: spi-nor: core: Use container_of to get the pointer to struct spi_nor
"struct mtd_info mtd" is member of "struct spi_nor", there's no need
to use "mtd->priv". Get the pointer to the containing struct spi_nor
by using container_of. While here, make the function inline and
get rid of the __maybe_unused.

Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Michael Walle <michael@walle.cc>
Reviewed-by: Pratyush Yadav <p.yadav@ti.com>
Link: https://lore.kernel.org/r/20211029172633.886453-3-tudor.ambarus@microchip.com
2021-11-17 14:36:01 +02:00
Tudor Ambarus a360ae4321 mtd: spi-nor: core: Fix spi_nor_flash_parameter otp description
Update the description of the otp member of the
struct spi_nor_flash_parameter.

Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Pratyush Yadav <p.yadav@ti.com>
Reviewed-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20211029172633.886453-2-tudor.ambarus@microchip.com
2021-11-17 14:36:01 +02:00
Michael Walle 36ac022862 mtd: spi-nor: add initial sysfs support
Add support to show the manufacturer, the partname and JEDEC identifier
as well as to dump the SFDP table. Not all flashes list their SFDP table
contents in their datasheet. So having that is useful. It might also be
helpful in bug reports from users.

Signed-off-by: Michael Walle <michael@walle.cc>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Acked-by: Pratyush Yadav <p.yadav@ti.com>
2021-06-15 23:18:32 +05:30
Michael Walle 65b6d89d45 mtd: spi-nor: sfdp: save a copy of the SFDP data
Due to possible mode switching to 8D-8D-8D, it might not be possible to
read the SFDP after the initial probe. To be able to dump the SFDP via
sysfs afterwards, make a complete copy of it.

Signed-off-by: Michael Walle <michael@walle.cc>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Tested-by: Heiko Thiery <heiko.thiery@gmail.com>
Reviewed-by: Pratyush Yadav <p.yadav@ti.com>
2021-06-15 23:18:31 +05:30
Michael Walle c6ec3e1e3a mtd: spi-nor: otp: implement erase for Winbond and similar flashes
Winbond flashes with OTP support provide a command to erase the OTP
data. This might come in handy during development.

This was tested with a Winbond W25Q32JW on a LS1028A SoC with the
NXP FSPI controller.

Signed-off-by: Michael Walle <michael@walle.cc>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Reviewed-by: Pratyush Yadav <p.yadav@ti.com>
Reviewed-by: Tudor Ambarus <tudor.ambarus@microchip.com>
2021-06-09 23:34:16 +05:30
Tudor Ambarus 1df1fc8c62 mtd: core: Constify buf in mtd_write_user_prot_reg()
The write buffer comes from user and should be const.
Constify write buffer in mtd core and across all _write_user_prot_reg()
users. cfi_cmdset_{0001, 0002} and onenand_base will pay the cost of an
explicit cast to discard the const qualifier since the beginning, since
they are using an otp_op_t function prototype that is used for both reads
and writes. mtd_dataflash and SPI NOR will benefit of the const buffer
because they are using different paths for writes and reads.

Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20210403060931.7119-1-tudor.ambarus@microchip.com
2021-04-16 20:30:54 +02:00
Michael Walle cad3193fe9 mtd: spi-nor: implement OTP support for Winbond and similar flashes
Use the new OTP ops to implement OTP access on Winbond flashes. Most
Winbond flashes provides up to four different OTP regions ("Security
Registers").

Winbond devices use a special opcode to read and write to the OTP
regions, just like the RDSFDP opcode. In fact, it seems that the
(undocumented) first OTP area of the newer flashes is the actual SFDP
table.

On a side note, Winbond devices also allow erasing the OTP regions as
long as the area isn't locked down.

Signed-off-by: Michael Walle <michael@walle.cc>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Link: https://lore.kernel.org/r/20210321235140.8308-3-michael@walle.cc
2021-04-02 09:32:27 +03:00
Michael Walle 069089acf8 mtd: spi-nor: add OTP support
SPI flashes sometimes have a special OTP area, which can (and is) used to
store immutable properties like board serial number or vendor assigned
network hardware addresses.

The MTD subsystem already supports accessing such areas and some (non
SPI NOR) flashes already implement support for it. It differentiates
between user and factory areas. User areas can be written by the user and
factory ones are pre-programmed and locked down by the vendor, usually
containing an "electrical serial number". This patch will only add support
for the user areas.

Lay the foundation and implement the MTD callbacks for the SPI NOR and add
necessary parameters to the flash_info structure. If a flash supports OTP
it can be added by the convenience macro OTP_INFO(). Sometimes there are
individual regions, which might have individual offsets. Therefore, it is
possible to specify the starting address of the first regions as well as
the distance between two regions (e.g. Winbond devices uses this method).

Additionally, the regions might be locked down. Once locked, no further
write access is possible.

For SPI NOR flashes the OTP area is accessed like the normal memory, e.g.
by offset addressing; except that you either have to use special read/write
commands (Winbond) or you have to enter (and exit) a specific OTP mode
(Macronix, Micron).

Thus we introduce four operations to which the MTD callbacks will be
mapped: .read(), .write(), .lock() and .is_locked(). The read and the write
ops will be given an address offset to operate on while the locking ops use
regions because locking always affects a whole region. It is up to the
flash driver to implement these ops.

Signed-off-by: Michael Walle <michael@walle.cc>
[ta: use div64_u64(), IS_ALIGNED, params->otp.org. unsigned int region,
drop comment, add rlen local variable in spi_nor_mtd_otp_lock()]
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Link: https://lore.kernel.org/r/20210321235140.8308-2-michael@walle.cc
2021-04-02 09:30:15 +03:00
Tudor Ambarus c4c795105f mtd: spi-nor: Move Software Write Protection logic out of the core
It makes the core file a bit smaller and provides better separation
between the Software Write Protection features and the core logic.
All the next generic software write protection features (e.g. Individual
Block Protection) will reside in swp.c.

Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Michael Walle <michael@walle.cc>
Acked-by: Pratyush Yadav <p.yadav@ti.com>
Link: https://lore.kernel.org/r/20210322075131.45093-2-tudor.ambarus@microchip.com
2021-03-31 22:41:34 +03:00
Tudor Ambarus a580293a19 mtd: spi-nor: Get rid of duplicated argument in spi_nor_parse_sfdp()
spi_nor_parse_sfdp(nor, nor->params);
passes for the second argument a member within the first argument.
Drop the second argument and obtain it directly from the first,
and do it across all the children functions. This is a follow up for
'commit 69a8eed58c ("mtd: spi-nor: Don't copy self-pointing struct around")'

Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Pratyush Yadav <p.yadav@ti.com>
Link: https://lore.kernel.org/r/20210306095002.22983-4-tudor.ambarus@microchip.com
2021-03-15 18:01:47 +02:00
Tudor Ambarus 75386810d3 mtd: spi-nor: sst: Add support for Global Unlock on sst26vf
Even if sst26vf shares the SPINOR_OP_GBULK opcode with
Macronix (ex. MX25U12835F) and Winbound (ex. W25Q128FV),
it has its own Individual Block Protection scheme, which
is also capable to read-lock individual parameter blocks.
Thus the sst26vf's Individual Block Protection scheme will
reside in the sst.c manufacturer driver.

Add support to unlock the entire flash memory. The device
is write-protected by default after a power-on reset cycle
(volatile software protection), in order to avoid inadvertent
writes during power-up. Could do an erase, write, read back,
and compare when MTD_SPI_NOR_SWP_DISABLE_ON_VOLATILE=y.

Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20210121110546.382633-2-tudor.ambarus@microchip.com
2021-02-05 15:24:59 +02:00
Tudor Ambarus a7a5acba0e mtd: spi-nor: Add Global Block Unlock command
The Global Block Unlock command has different names depending
on the manufacturer, but always the same command value: 0x98.
Macronix's MX25U12835F names it Gang Block Unlock, Winbond's
W25Q128FV names it Global Block Unlock and Microchip's
SST26VF064B names it Global Block Protection Unlock.

Used in the Individual Block Protection mode, which is mutually
exclusive with the Block Protection mode (BP0-3).

Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Pratyush Yadav <p.yadav@ti.com>
Reviewed-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20210121110546.382633-1-tudor.ambarus@microchip.com
2021-02-05 15:24:59 +02:00
Michael Walle 31ad3eff09 mtd: spi-nor: keep lock bits if they are non-volatile
Traditionally, Linux unlocks the whole flash because there are legacy
devices which has the write protection bits set by default at startup.
If you actually want to use the flash protection bits, eg. because there
is a read-only part for a bootloader, this automatic unlocking is
harmful. If there is no hardware write protection in place (usually
called WP#), a startup of the kernel just discards this protection.

I've gone through the datasheets of all the flashes (except the Intel
ones where I could not find any datasheet nor reference) which supports
the unlocking feature and looked how the sector protection was
implemented. The currently supported flashes can be divided into the
following two categories:
 (1) block protection bits are non-volatile. Thus they keep their values
     at reset and power-cycle
 (2) flashes where these bits are volatile. After reset or power-cycle,
     the whole memory array is protected.
     (a) some devices needs a special "Global Unprotect" command, eg.
         the Atmel AT25DF041A.
     (b) some devices require to clear the BPn bits in the status
         register.

Due to the reasons above, we do not want to clear the bits for flashes
which belong to category (1). Fortunately for us, only Atmel flashes
fall into category (2a). Implement the "Global Protect" and "Global
Unprotect" commands for these. For (2b) we can use normal block
protection locking scheme.

This patch adds a new flag to indicate the case (2). Only if we have
such a flash we unlock the whole flash array. To be backwards compatible
it also introduces a kernel configuration option which restores the
complete legacy behavior ("Disable write protection on any flashes").
Hopefully, this will clean up "unlock the entire flash for legacy
devices" once and for all.

For reference here are the actually commits which introduced the legacy
behavior (and extended the behavior to other chip manufacturers):

commit f80e521c91 ("mtd: m25p80: add support for the Intel/Numonyx {16,32,64}0S33B SPI flash chips")
commit ea60658a08 ("mtd: m25p80: disable SST software protection bits by default")
commit 7228982442 ("[MTD] m25p80: fix bug - ATmel spi flash fails to be copied to")

Actually, this might also fix handling of the Atmel AT25DF flashes,
because the original commit 7228982442 ("[MTD] m25p80: fix bug -
ATmel spi flash fails to be copied to") was writing a 0 to the status
register, which is a "Global Unprotect". This might not be the case in
the current code which only handles the block protection bits BP2, BP1
and BP0. Thus, it depends on the current contents of the status register
if this unlock actually corresponds to a "Global Unprotect" command. In
the worst case, the current code might leave the AT25DF flashes in a
write protected state.

The commit 191f5c2ed4 ("mtd: spi-nor: use 16-bit WRR command when QE
is set on spansion flashes") changed that behavior by just clearing BP2
to BP0 instead of writing a 0 to the status register.

Further, the commit 3e0930f109 ("mtd: spi-nor: Rework the disabling
of block write protection") expanded the unlock_all() feature to ANY
flash which supports locking.

Signed-off-by: Michael Walle <michael@walle.cc>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Reviewed-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Link: https://lore.kernel.org/r/20201203162959.29589-8-michael@walle.cc
2020-12-07 23:01:15 +05:30
Michael Walle 8c174d1511 mtd: spi-nor: atmel: fix unlock_all() for AT25FS010/040
These flashes have some weird BP bits mapping which aren't supported in
the current locking code. Just add a simple unlock op to unprotect the
entire flash array which is needed for legacy behavior.

Fixes: 3e0930f109 ("mtd: spi-nor: Rework the disabling of block write protection")
Signed-off-by: Michael Walle <michael@walle.cc>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Reviewed-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Link: https://lore.kernel.org/r/20201203162959.29589-7-michael@walle.cc
2020-12-07 22:57:30 +05:30
Pratyush Yadav afd473e858 mtd: spi-nor: core: Allow flashes to specify MTD writesize
Some flashes like the Cypress S28 family use ECC. Under this ECC scheme,
multi-pass writes to an ECC block is not allowed. In other words, once
data is programmed to an ECC block, it can't be programmed again without
erasing it first.

Upper layers like file systems need to be given this information so they
do not cause error conditions on the flash by attempting multi-pass
programming. This can be done by setting 'writesize' in 'struct
mtd_info'.

Set the default to 1 but allow flashes to modify it in fixup hooks. If
more flashes show up with this constraint in the future it might be
worth it to add it to 'struct flash_info', but for now increasing its
size is not worth it.

Signed-off-by: Pratyush Yadav <p.yadav@ti.com>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Reviewed-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Link: https://lore.kernel.org/r/20201201102711.8727-3-p.yadav@ti.com
2020-12-07 22:57:29 +05:30
Pratyush Yadav 1131324aa5 mtd: spi-nor: sfdp: detect Soft Reset sequence support from BFPT
A Soft Reset sequence will return the flash to Power-on-Reset (POR)
state. It consists of two commands: Soft Reset Enable and Soft Reset.
Find out if the sequence is supported from BFPT DWORD 16.

Signed-off-by: Pratyush Yadav <p.yadav@ti.com>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Reviewed-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Link: https://lore.kernel.org/r/20201005153138.6437-12-p.yadav@ti.com
2020-11-09 11:56:17 +05:30
Pratyush Yadav a33c89db4c mtd: spi-nor: core: enable octal DTR mode when possible
Allow flashes to specify a hook to enable octal DTR mode. Use this hook
whenever possible to get optimal transfer speeds.

Signed-off-by: Pratyush Yadav <p.yadav@ti.com>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Reviewed-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Link: https://lore.kernel.org/r/20201005153138.6437-11-p.yadav@ti.com
2020-11-09 11:56:17 +05:30
Tudor Ambarus c6908077b1 mtd: spi-nor: Introduce SNOR_F_IO_MODE_EN_VOLATILE
We don't want to enter a stateful mode, where a X-X-X I/O mode
is entered by setting a non-volatile bit, because in case of a
reset or a crash, once in the non-volatile mode, we may not be able
to recover in bootloaders and we may break the SPI NOR boot.

Forbid by default the I/O modes that are set via a non-volatile bit.

SPI_NOR_IO_MODE_EN_VOLATILE should be set just for the flashes that
don't define the optional SFDP SCCR Map, so that we don't pollute the
flash info flags.

Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Signed-off-by: Pratyush Yadav <p.yadav@ti.com>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Link: https://lore.kernel.org/r/20201005153138.6437-9-p.yadav@ti.com
2020-11-09 11:56:16 +05:30
Pratyush Yadav fb27f19897 mtd: spi-nor: sfdp: parse xSPI Profile 1.0 table
This table is indication that the flash is xSPI compliant and hence
supports octal DTR mode. Extract information like the fast read opcode,
dummy cycles, the number of dummy cycles needed for a Read Status
Register command, and the number of address bytes needed for a Read
Status Register command.

We don't know what speed the controller is running at. Find the fast
read dummy cycles for the fastest frequency the flash can run at to be
sure we are never short of dummy cycles. If nothing is available,
default to 20. Flashes that use a different value should update it in
their fixup hooks.

Since we want to set read settings, expose spi_nor_set_read_settings()
in core.h.

Signed-off-by: Pratyush Yadav <p.yadav@ti.com>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Reviewed-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Link: https://lore.kernel.org/r/20201005153138.6437-6-p.yadav@ti.com
2020-11-09 11:56:16 +05:30
Pratyush Yadav 0e30f47232 mtd: spi-nor: add support for DTR protocol
Double Transfer Rate (DTR) is SPI protocol in which data is transferred
on each clock edge as opposed to on each clock cycle. Make
framework-level changes to allow supporting flashes in DTR mode.

Right now, mixed DTR modes are not supported. So, for example a mode
like 4S-4D-4D will not work. All phases need to be either DTR or STR.

The xSPI spec says that "The program commands provide SPI backward
compatible commands for programming data...". So 8D-8D-8D page program
opcodes are populated with using 1S-1S-1S opcodes.

Signed-off-by: Pratyush Yadav <p.yadav@ti.com>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Reviewed-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Link: https://lore.kernel.org/r/20201005153138.6437-4-p.yadav@ti.com
2020-11-09 11:56:16 +05:30
Yicong Yang 1afc0c89f6 Revert "mtd: spi-nor: Add capability to disable flash quad mode"
As the only user has been removed in previous patch, let's revert
this one together.

This reverts commit be192209d5.

Reported-by: Matthias Weisser <m.weisser.m@gmail.com>
Suggested-by: Vignesh Raghavendra <vigneshr@ti.com>
Signed-off-by: Yicong Yang <yangyicong@hisilicon.com>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Link: https://lore.kernel.org/r/1599205640-26690-2-git-send-email-yangyicong@hisilicon.com
2020-09-14 20:58:27 +05:30
Yicong Yang be192209d5 mtd: spi-nor: Add capability to disable flash quad mode
Previous we didn't provide a way to disable the flash's quad mode.
Which means we cannot do some cleanup works when to remove or
poweroff the flash, like what set 4-byte address mode does in
spi_nor_restore().

Add the capability to disable the flash quad mode, by introducing
an enable flag in the flash parameters quad_enable() hooks and
related functions.

Signed-off-by: Yicong Yang <yangyicong@hisilicon.com>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Pratyush Yadav <p.yadav@ti.com>
Link: https://lore.kernel.org/r/1594027356-19088-2-git-send-email-yangyicong@hisilicon.com
2020-07-13 12:09:43 +03:00
Jungseung Lee 05635c14a2
mtd: spi-nor: Add SR 4bit block protection support
Currently we are supporting block protection only for flash chips with
3 block protection bits (BP0-2) in the SR register.

Enable block protection support for flashes with 4 block protection bits
(BP0-3).

Add a flash_info flag for flashes that describe 4 block protection bits.
Add another flash_info flag for flashes in which BP3 bit is not adjacent
to the BP0-2 bits.

Tested with a n25q512ax3 (BP0-3) and w25q128 (BP0-2).

Signed-off-by: Jungseung Lee <js07.lee@samsung.com>
Reviewed-by: Michael Walle <michael@walle.cc>
Tested-by: Michael Walle <michael@walle.cc>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
2020-03-24 11:47:42 +02:00
Tudor Ambarus 829ec6408d
mtd: spi-nor: Trim what is exposed in spi-nor.h
The SPI NOR controllers drivers must not be able to use structures that
are meant just for the SPI NOR core.

struct spi_nor_flash_parameter is filled at run-time with info gathered
from flash_info, manufacturer and sfdp data. struct spi_nor_flash_parameter
should be opaque to the SPI NOR controller drivers, make sure it is.

spi_nor_option_flags, spi_nor_read_command, spi_nor_pp_command,
spi_nor_read_command_index and spi_nor_pp_command_index are defined for the
core use, make sure they are opaque to the SPI NOR controller drivers.

Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Vignesh Raghavendra <vigneshr@ti.com>
2020-03-17 09:28:07 +02:00
Boris Brezillon a674d5a6c8
mtd: spi-nor: Move XMC bits out of core.c
Create a SPI NOR manufacturer driver for XMC chips, and move the
XMC definitions outside of core.c.

Signed-off-by: Boris Brezillon <bbrezillon@kernel.org>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
2020-03-17 09:28:06 +02:00
Boris Brezillon 2d47cac1ee
mtd: spi-nor: Move Xilinx bits out of core.c
Create a SPI NOR manufacturer driver for Xilinx chips, and move the
Xilinx definitions outside of core.c.

While at it, remove the SPI_S3AN flag which is now useless.

Signed-off-by: Boris Brezillon <bbrezillon@kernel.org>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
2020-03-17 09:28:06 +02:00
Boris Brezillon d825925726
mtd: spi-nor: Move Catalyst bits out of core.c
Create a SPI NOR manufacturer driver for Catalyst chips, and move the
Catalyst definitions outside of core.c.

Signed-off-by: Boris Brezillon <bbrezillon@kernel.org>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
2020-03-17 09:28:05 +02:00
Boris Brezillon 7b8b22010a
mtd: spi-nor: Move Winbond bits out of core.c
Create a SPI NOR manufacturer driver for Winbond chips, and move the
Winbond definitions outside of core.c.

Signed-off-by: Boris Brezillon <bbrezillon@kernel.org>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
2020-03-17 09:28:05 +02:00
Boris Brezillon c53b3f92b4
mtd: spi-nor: Move SST bits out of core.c
Create a SPI NOR manufacturer driver for SST chips, and move the
SST definitions outside of core.c.

Signed-off-by: Boris Brezillon <bbrezillon@kernel.org>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
2020-03-17 09:28:05 +02:00
Boris Brezillon 0173c32a0e
mtd: spi-nor: Move Spansion bits out of core.c
Create a SPI NOR manufacturer driver for Spansion chips, and move the
Spansion definitions outside of core.c.

Signed-off-by: Boris Brezillon <bbrezillon@kernel.org>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
2020-03-17 09:28:05 +02:00
Boris Brezillon 15f5c7e54e
mtd: spi-nor: Move Micron/ST bits out of core.c
Create a SPI NOR manufacturer driver for Micron/ST chips, and move the
Micron/ST definitions outside of core.c.

Signed-off-by: Boris Brezillon <bbrezillon@kernel.org>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
2020-03-17 09:28:04 +02:00