Hi,
Looking in Documentation/devicetree/bindings/mtd/mtd.yaml
I see you are defining OTP in a different way, as partitions.
Each partition is an OTP region which can be user or factory mode
(since many chips do not define or enforce it).
While I try to define the OTP parameters.
I wonder what you think?
Should the parameter be in the partitions?
Do we wish to support asymmetric OTP?
I only found asymmetric OTP (OTP with different region sizes) with old
chips. But perhaps I missed it.
Erez
diff --git a/Documentation/devicetree/bindings/mtd/jedec,spi-nor.yaml
b/Documentation/devicetree/bindings/mtd/jedec,spi-nor.yaml
index 6e3afb42926e..5fde51309b93 100644
--- a/Documentation/devicetree/bindings/mtd/jedec,spi-nor.yaml
+++ b/Documentation/devicetree/bindings/mtd/jedec,spi-nor.yaml
@@ -90,6 +90,47 @@ properties:
the SRWD bit while writing the status register. WP# signal hard
strapped to GND
can be a valid use case.
+ opt_n_regions:
+ type: u32
+ description:
+ Some flash devices need OTP parameters in the device tree.
+ As we can not deduce the parameters based on JEDEC ID,
+ or SFDP.
+ This parameter indicates the number of OTP regions.
+ The value must be larger than 1 and mandatory for OTP.
+
+ otp_len:
+ type: u32
+ description:
+ Some flash devices need OTP parameters in the device tree.
+ As we can not deduce the parameters based on JEDEC ID,
+ or SFDP.
+ This parameter indicates the size (length) in bytes of an OTP region.
+ Currently the driver supports symmetric OTP,
+ which means all regions must use the same size.
+ The value must be positive and mandatory for OTP.
+
+ otp_offset:
+ type: u32
+ description:
+ Some flash devices need OTP parameters in the device tree.
+ As we can not deduce the parameters based on JEDEC ID,
+ or SFDP.
+ This parameter indicates the offset in bytes of
+ an OTP region relative to its previous.
+ User can omit it if the offset equals the length.
+ Or in case we have a single OTP region.
+
+ otp_base:
+ type: u32
+ description:
+ Some flash devices need OTP parameters in the device tree.
+ As we can not deduce the parameters based on JEDEC ID,
+ or SFDP.
+ This parameter indicates the base in bytes of the first OTP region.
+ User can omit it if the base is zero.
+ I.e. the address of the first OTP region starts from 0.
+
reset-gpios:
description:
A GPIO line connected to the RESET (active low) signal of the device.
On Sat, 17 Aug 2024 at 14:42, Erez Geva <erezgeva@xxxxxxxxxx> wrote:
>
> From: Erez Geva <ErezGeva2@xxxxxxxxx>
>
> Add support for SPI-NOR Macronix OTP.
> And add MX25L12833F with OTP.
>
> TODO:
> - Test OTP with 'flash_otp_write' and 'flash_otp_lock'
> - Question: Do we need documentation on new DT OTP parameters?
>
> v2:
> Improve description of mx25l12833f.
> Add note about mx25l12833f using the same JEDEC ID as mx25l12805d.
>
> v3:
> Improve description.
> Rename _nor_send_cmd() to spi_nor_send_cmd_internal()
> Remove MX25L12833F specific changes.
> Add reading SFDP to all Macronix chips.
> Add support of reading OTP parameters from device tree.
> Reorgenize patches to 2 SPI-NOR patches and 2 Macronix patches
> Testing with MX25L3233F using BeagleBone Black.
> Test results are in "mtd: spi-nor: macronix: add manufacturer flags" patch
>
> Erez Geva (4):
> mtd: spi-nor: core: add manufacturer flags
> mtd: spi-nor: core: add generic functions
> mtd: spi-nor: macronix: add support for OTP
> mtd: spi-nor: macronix: add manufacturer flags
>
> drivers/mtd/spi-nor/core.c | 166 ++++++++++++++++++++++-------
> drivers/mtd/spi-nor/core.h | 34 ++----
> drivers/mtd/spi-nor/macronix.c | 186 +++++++++++++++++++++++++++++++++
> drivers/mtd/spi-nor/otp.c | 6 +-
> drivers/mtd/spi-nor/winbond.c | 2 +-
> include/linux/mtd/spi-nor.h | 10 ++
> 6 files changed, 336 insertions(+), 68 deletions(-)
>
> --
> 2.39.2
>
