Add two flags for inserting the Plane Select bit into the column
address during the write_to_cache and the read_from_cache operation.
Add the SPINAND_HAS_PROG_PLANE_SELECT_BIT flag for serial NAND flash
that require inserting the Plane Select bit into the column address
during the write_to_cache operation.
Add the SPINAND_HAS_READ_PLANE_SELECT_BIT flag for serial NAND flash
that require inserting the Plane Select bit into the column address
during the read_from_cache operation.
Signed-off-by: Cheng Ming Lin <chengminglin@mxic.com.tw>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20240909092643.2434479-2-linchengming884@gmail.com
This helper function will soon be used from a vendor driver, let's
export it through the spinand.h header. No need for any export, as there
is currently no reason for any module to need it.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20240826101412.20644-6-miquel.raynal@bootlin.com
A regular page read consist in:
- Asking one page of content from the NAND array to be loaded in the
chip's SRAM,
- Waiting for the operation to be done,
- Retrieving the data (I/O phase) from the chip's SRAM.
When reading several sequential pages, the above operation is repeated
over and over. There is however a way to optimize these accesses, by
enabling continuous reads. The feature requires the NAND chip to have a
second internal SRAM area plus a bit of additional internal logic to
trigger another internal transfer between the NAND array and the second
SRAM area while the I/O phase is ongoing. Once the first I/O phase is
done, the host can continue reading more data, continuously, as the chip
will automatically switch to the second SRAM content (which has already
been loaded) and in turns trigger the next load into the first SRAM area
again.
From an instruction perspective, the command op-codes are different, but
the same cycles are required. The only difference is that after a
continuous read (which is stopped by a CS deassert), the host must
observe a delay of tRST. However, because there is no guarantee in Linux
regarding the actual state of the CS pin after a transfer (in order to
speed-up the next transfer if targeting the same device), it was
necessary to manually end the continuous read with a configuration
register write operation.
Continuous reads have two main drawbacks:
* They only work on full pages (column address ignored)
* Only the main data area is pulled, out-of-band bytes are not
accessible. Said otherwise, the feature can only be useful with on-die
ECC engines.
Performance wise, measures have been performed on a Zynq platform using
Macronix SPI-NAND controller with a Macronix chip (based on the
flash_speed tool modified for testing sequential reads):
- 1-1-1 mode: performances improved from +3% (2-pages) up to +10% after
a dozen pages.
- 1-1-4 mode: performances improved from +15% (2-pages) up to +40% after
a dozen pages.
This series is based on a previous work from Macronix engineer Jaime
Liao.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Pratyush Yadav <pratyush@kernel.org>
Link: https://lore.kernel.org/linux-mtd/20240826101412.20644-5-miquel.raynal@bootlin.com
E.g. ESMT chips will return an identification code with a length of 5
bytes. In order to prevent ambiguity, flash chips would actually need to
return IDs that are up to 17 or more bytes long due to JEDEC's
continuation scheme. I understand that if a manufacturer ID is located
in bank N of JEDEC's database (there are currently 16 banks), N - 1
continuation codes (7Fh) need to be added to the identification code
(comprising of manufacturer ID and device ID). However, most flash chip
manufacturers don't seem to implement this (correctly).
Signed-off-by: Ezra Buehler <ezra.buehler@husqvarnagroup.com>
Reviewed-by: Martin Kurbanov <mmkurbanov@salutedevices.com>
Tested-by: Martin Kurbanov <mmkurbanov@salutedevices.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20240125200108.24374-2-ezra@easyb.ch
In order for pipelined ECC engines to be able to enable/disable the ECC
engine only when needed and avoid races when future parallel-operations
will be supported, we need to provide the information about the use of
the ECC engine in the direct mapping hooks. As direct mapping
configurations are meant to be static, it is best to create two new
mappings: one for regular 'raw' accesses and one for accesses involving
correction. It is up to the driver to use or not the new ECC enable
boolean contained in the spi-mem operation.
As dirmaps are not free (they consume a few pages of MMIO address space)
and because these extra entries are only meant to be used by pipelined
engines, let's limit their use to this specific type of engine and save
a bit of memory with all the other setups.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Link: https://lore.kernel.org/linux-mtd/20220127091808.1043392-9-miquel.raynal@bootlin.com
Make use of spi-mem poll status APIs to let advanced controllers
optimize wait operations.
This should also fix the high CPU usage for system that don't have
a dedicated STATUS poll block logic.
Signed-off-by: Patrice Chotard <patrice.chotard@foss.st.com>
Signed-off-by: Christophe Kerello <christophe.kerello@foss.st.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Acked-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/r/20210518162754.15940-3-patrice.chotard@foss.st.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Make use of the existing functions taken from the SPI-NAND core to
instantiate an on-die ECC engine specific to the SPI-NAND core. The
next step will be to tweak the core to use this object instead of
calling the helpers directly.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200930154109.3922-4-miquel.raynal@bootlin.com
Prepare the migration to a generic ECC engine by renaming the
nand_ecc_req structure into nand_ecc_props. This structure will be the
base of a wider 'nand_ecc' structure.
In nand_device, these properties are still named "eccreq" even if
"eccprops" might be more descriptive. This is just a transition step,
this field is being replaced very soon by a much wider structure. The
impact of renaming this field would be huge compared to its interest.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Link: https://lore.kernel.org/linux-mtd/20200529002517.3546-14-miquel.raynal@bootlin.com
Add SPINAND_HAS_CR_FEAT_BIT flag to identify the SPI NAND device with
the Continuous Read mode.
Some of the Micron SPI NAND devices have the "Continuous Read" feature
enabled by default, which does not fit the subsystem needs.
In this mode, the READ CACHE command doesn't require the starting column
address. The device always output the data starting from the first
column of the cache register, and once the end of the cache register
reached, the data output continues through the next page. With the
continuous read mode, it is possible to read out the entire block using
a single READ command, and once the end of the block reached, the output
pins become High-Z state. However, during this mode the read command
doesn't output the OOB area.
Hence, we disable the feature at probe time.
Signed-off-by: Shivamurthy Shastri <sshivamurthy@micron.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200311175735.2007-5-sshivamurthy@micron.com
Currently there are 3 different variants of read_id implementation:
1. opcode only. Found in GD5FxGQ4xF.
2. opcode + 1 addr byte. Found in GD5GxGQ4xA/E
3. opcode + 1 dummy byte. Found in other currently supported chips.
Original implementation was for variant 1 and let detect function
of chips with variant 2 and 3 to ignore the first byte. This isn't
robust:
1. For chips of variant 2, if SPI master doesn't keep MOSI low
during read, chip will get a random id offset, and the entire id
buffer will shift by that offset, causing detect failure.
2. For chips of variant 1, if it happens to get a devid that equals
to manufacture id of variant 2 or 3 chips, it'll get incorrectly
detected.
This patch reworks detect procedure to address problems above. New
logic do detection for all variants separatedly, in 1-2-3 order.
Since all current detect methods do exactly the same id matching
procedure, unify them into core.c and remove detect method from
manufacture_ops.
Tested on GD5F1GQ4UAYIG and W25N01GVZEIG.
Signed-off-by: Chuanhong Guo <gch981213@gmail.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200208074439.146296-1-gch981213@gmail.com
Make use of the spi-mem direct mapping API to let advanced controllers
optimize read/write operations when they support direct mapping.
Signed-off-by: Boris Brezillon <bbrezillon@kernel.org>
Cc: Stefan Roese <sr@denx.de>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Tested-by: Stefan Roese <sr@denx.de>
Add minimal support for the MX35LF1GE4AB SPI NAND chip.
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Add support for the W25M02GV chip.
Signed-off-by: Frieder Schrempf <frieder.schrempf@exceet.de>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Add a basic driver for Micron SPI NANDs. Only one device is supported
right now, but the driver will be extended to support more devices
afterwards.
Signed-off-by: Peter Pan <peterpandong@micron.com>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Add a SPI NAND framework based on the generic NAND framework and the
spi-mem infrastructure.
In its current state, this framework supports the following features:
- single/dual/quad IO modes
- on-die ECC
Signed-off-by: Peter Pan <peterpandong@micron.com>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>