[PATCH] dt-bindings: mtd: convert "fixed-partitions" to the json-schema
Rafał Miłecki
zajec5 at gmail.com
Thu Dec 10 08:56:47 EST 2020
On 10.12.2020 03:48, Rob Herring wrote:
> On Wed, Dec 09, 2020 at 02:02:35PM +0100, Rafał Miłecki wrote:
>> From: Rafał Miłecki <rafal at milecki.pl>
>>
>> This standardizes its documentation, allows validating with Makefile
>> checks and helps writing DTS files.
>>
>> Noticeable changes:
>> 1. Dropped "Partitions can be represented by sub-nodes of a flash
>> device." as we also support subpartitions (don't have to be part of
>> flash device node)
>> 2. Dropped "to Linux" as bindings are meant to be os agnostic.
>>
>> Signed-off-by: Rafał Miłecki <rafal at milecki.pl>
>> ---
>> .../devicetree/bindings/mtd/partition.txt | 131 +---------------
>> .../mtd/partitions/fixed-partitions.yaml | 146 ++++++++++++++++++
>> 2 files changed, 148 insertions(+), 129 deletions(-)
>> create mode 100644 Documentation/devicetree/bindings/mtd/partitions/fixed-partitions.yaml
>>
>> diff --git a/Documentation/devicetree/bindings/mtd/partition.txt b/Documentation/devicetree/bindings/mtd/partition.txt
>> index 4a39698221a2..ead90e8274d6 100644
>> --- a/Documentation/devicetree/bindings/mtd/partition.txt
>> +++ b/Documentation/devicetree/bindings/mtd/partition.txt
>> @@ -24,137 +24,10 @@ another partitioning method.
>> Available bindings are listed in the "partitions" subdirectory.
>>
>>
>> -Fixed Partitions
>> -================
>> -
>> -Partitions can be represented by sub-nodes of a flash device. This can be used
>> -on platforms which have strong conventions about which portions of a flash are
>> -used for what purposes, but which don't use an on-flash partition table such
>> -as RedBoot.
>> -
>> -The partition table should be a subnode of the flash node and should be named
>> -'partitions'. This node should have the following property:
>> -- compatible : (required) must be "fixed-partitions"
>> -Partitions are then defined in subnodes of the partitions node.
>> +Deprecated: partitions defined in flash node
>> +============================================
>>
>> For backwards compatibility partitions as direct subnodes of the flash device are
>> supported. This use is discouraged.
>> NOTE: also for backwards compatibility, direct subnodes that have a compatible
>> string are not considered partitions, as they may be used for other bindings.
>> -
>> -#address-cells & #size-cells must both be present in the partitions subnode of the
>> -flash device. There are two valid values for both:
>> -<1>: for partitions that require a single 32-bit cell to represent their
>> - size/address (aka the value is below 4 GiB)
>> -<2>: for partitions that require two 32-bit cells to represent their
>> - size/address (aka the value is 4 GiB or greater).
>> -
>> -Required properties:
>> -- reg : The partition's offset and size within the flash
>> -
>> -Optional properties:
>> -- label : The label / name for this partition. If omitted, the label is taken
>> - from the node name (excluding the unit address).
>> -- read-only : This parameter, if present, is a hint to Linux that this
>> - partition should only be mounted read-only. This is usually used for flash
>> - partitions containing early-boot firmware images or data which should not be
>> - clobbered.
>> -- lock : Do not unlock the partition at initialization time (not supported on
>> - all devices)
>> -- slc-mode: This parameter, if present, allows one to emulate SLC mode on a
>> - partition attached to an MLC NAND thus making this partition immune to
>> - paired-pages corruptions
>> -
>> -Examples:
>> -
>> -
>> -flash at 0 {
>> - partitions {
>> - compatible = "fixed-partitions";
>> - #address-cells = <1>;
>> - #size-cells = <1>;
>> -
>> - partition at 0 {
>> - label = "u-boot";
>> - reg = <0x0000000 0x100000>;
>> - read-only;
>> - };
>> -
>> - uimage at 100000 {
>> - reg = <0x0100000 0x200000>;
>> - };
>> - };
>> -};
>> -
>> -flash at 1 {
>> - partitions {
>> - compatible = "fixed-partitions";
>> - #address-cells = <1>;
>> - #size-cells = <2>;
>> -
>> - /* a 4 GiB partition */
>> - partition at 0 {
>> - label = "filesystem";
>> - reg = <0x00000000 0x1 0x00000000>;
>> - };
>> - };
>> -};
>> -
>> -flash at 2 {
>> - partitions {
>> - compatible = "fixed-partitions";
>> - #address-cells = <2>;
>> - #size-cells = <2>;
>> -
>> - /* an 8 GiB partition */
>> - partition at 0 {
>> - label = "filesystem #1";
>> - reg = <0x0 0x00000000 0x2 0x00000000>;
>> - };
>> -
>> - /* a 4 GiB partition */
>> - partition at 200000000 {
>> - label = "filesystem #2";
>> - reg = <0x2 0x00000000 0x1 0x00000000>;
>> - };
>> - };
>> -};
>> -
>> -flash at 3 {
>> - partitions {
>> - compatible = "fixed-partitions";
>> - #address-cells = <1>;
>> - #size-cells = <1>;
>> -
>> - partition at 0 {
>> - label = "bootloader";
>> - reg = <0x000000 0x100000>;
>> - read-only;
>> - };
>> -
>> - firmware at 100000 {
>> - label = "firmware";
>> - reg = <0x100000 0xe00000>;
>> - compatible = "brcm,trx";
>> - };
>> -
>> - calibration at f00000 {
>> - label = "calibration";
>> - reg = <0xf00000 0x100000>;
>> - compatible = "fixed-partitions";
>> - ranges = <0 0xf00000 0x100000>;
>> - #address-cells = <1>;
>> - #size-cells = <1>;
>> -
>> - partition at 0 {
>> - label = "wifi0";
>> - reg = <0x000000 0x080000>;
>> - };
>> -
>> - partition at 80000 {
>> - label = "wifi1";
>> - reg = <0x080000 0x080000>;
>> - };
>> - };
>> - };
>> -};
>> diff --git a/Documentation/devicetree/bindings/mtd/partitions/fixed-partitions.yaml b/Documentation/devicetree/bindings/mtd/partitions/fixed-partitions.yaml
>> new file mode 100644
>> index 000000000000..c5e509e08f31
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/mtd/partitions/fixed-partitions.yaml
>> @@ -0,0 +1,146 @@
>> +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
>> +%YAML 1.2
>> +---
>> +$id: http://devicetree.org/schemas/mtd/partitions/fixed-partitions.yaml#
>> +$schema: http://devicetree.org/meta-schemas/core.yaml#
>> +
>> +title: Fixed partitions
>> +
>> +description: |
>> + This binding can be used on platforms which have strong conventions about
>> + which portions of a flash are used for what purposes, but which don't use an
>> + on-flash partition table such as RedBoot.
>> +
>> + The partition table should be a node named "partitions". Partitions are then
>> + defined as subnodes.
>> +
>> +maintainers:
>> + - Rafał Miłecki <rafal at milecki.pl>
>> +
>> +properties:
>> + compatible:
>> + const: fixed-partitions
>> +
>> +patternProperties:
>> + "^.*@[0-9a-f]+$":
>
> You can drop '^.*'.
>
> This needs to recurse to nested nodes.
>
> I think here you can do just:
>
> $ref: #/
>
> And drop 'compatible' as required. It's redundant anyways because the
> schema will only be applied if compatible matches.
I managed to implement recursive schema but then I run dt_binding_check and
realized it may be not what we really want.
The error I got was:
Documentation/devicetree/bindings/mtd/partitions/fixed-partitions.example.dt.yaml: partitions: firmware at 100000:compatible:0: 'fixed-partitions' was expected
From schema: Documentation/devicetree/bindings/mtd/partitions/fixed-partitions.yaml
and was caused by the following example:
partitions {
compatible = "fixed-partitions";
#address-cells = <1>;
#size-cells = <1>;
(...)
firmware at 100000 {
label = "firmware";
reg = <0x100000 0xe00000>;
compatible = "brcm,trx";
};
(...)
}
As you can see a single partition can use any available parser, so we can't
require only "fixed-partitions" to be nested in the "fixed-partitions".
In this situation I think this commit may be OK after all if I just fix regex
and required (drop "compatible").
What do you think?
FWIW:
properties:
compatible:
const: fixed-partitions
patternProperties:
"@[0-9a-f]+$":
allOf:
- $ref: "#"
- properties:
reg:
maxItems: 1
description: partition's offset and size within the flash
label:
description: The label / name for this partition. If omitted, the label
is taken from the node name (excluding the unit address).
read-only:
description: This parameter, if present, is a hint that this partition
should only be mounted read-only. This is usually used for flash
partitions containing early-boot firmware images or data which should
not be clobbered.
type: boolean
lock:
description: Do not unlock the partition at initialization time (not
supported on all devices)
type: boolean
slc-mode:
description: This parameter, if present, allows one to emulate SLC mode
on a partition attached to an MLC NAND thus making this partition
immune to paired-pages corruptions
type: boolean
required:
- reg
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