On 5/1/2022 7:17 PM, Krzysztof Kozlowski wrote:
> On 01/05/2022 16:51, Mikhail Zhilkin wrote:
>> On 5/1/2022 11:17 AM, Krzysztof Kozlowski wrote:
>>
>>> On 30/04/2022 20:54, Mikhail Zhilkin wrote:
>>>> patternProperties:
>>>> "@[0-9a-f]+$":
>>>> - $ref: "partition.yaml#"
>>>> + allOf:
>>>> + - $ref: "partition.yaml#"
>>>> + - if:
>>>> + properties:
>>>> + compatible:
>>>> + contains:
>>>> + const: sercomm,sc-partitions
>>>> + then:
>>>> + properties:
>>>> + sercomm,scpart-id:
>>>> + description: Partition id in Sercomm partition map. Parser
>>>> + uses this id to get partition offset and size values from
>>>> + dynamic partition map.
>>> Partition offset and size values are not derived from scpart-id. I am
>>> sorry but after all these questions - it's the third time now - you
>>> never answer why do you need this property and what is it used for. From
>>> all the examples it could be simply removed and the partition map will
>>> be exactly the same.
>> scpart-id is necessary to get (using mtd parser) partition offset and
>> size from dynamic partition map (NOT from the reg property):
>>
>> ❯ xxd -e -c 12 -s $((0x800)) -l $((0x78)) mtd1
>> 00000800: 00000000 00000000 00100000 ............
>> 0000080c: 00000001 00100000 00100000 ............
>> 00000818: 00000002 00200000 00100000 ...... .....
>> 00000824: 00000003 00300000 00100000 ......0.....
>> 00000830: 00000004 00400000 00600000 ......@...`.
>> 0000083c: 00000005 00a00000 00600000 ..........`.
>> 00000848: 00000006 01000000 02000000 ............
>> 00000854: 00000007 03000000 02000000 ............
>> 00000860: 00000008 05000000 01400000 ..........@.
>> 0000086c: 00000009 06400000 01b80000 ......@.....
>> scpart-id offset size
>>
>> With sercomm,sc-partitions the reg property will be ignored (offset =
>> 0x200000, size = 0x100000) and the values will be taken from partition map.
>>
>> For example we have this is dts:
>>
>> partition@200000 {
>> label = "Factory";
>> reg = <0x200000 0x100000>;
>> sercomm,scpart-id = <2>;
>> read-only;
>> };
>>
>> Dynamic partition map:
>>
>> scpart-id = 2; offset = 0x00200000; size = 0x00100000
>>
>> 00000002 00200000 00100000 ...... .....
>>
>> In this example the offset and size are the same in reg and dynamic
>> partition map. If device have bad blocks on NAND the values will be a
>> little different. And we have to take partition offsets from partition
>> map to avoid boot loops, wrong eeprom location and other bad things.
>>
>> Is there anything that needs to be explained in more detail?
> Thanks a lot, this clarifies the topic. Looks good. Maybe you could put
> parts of this into the scpart-id field description?
Thank you for you support! I updated the scpart-id description and hope
this should be clear enough. If so, I'll prepare PATCH v3.
patternProperties:
"@[0-9a-f]+$":
- $ref: "partition.yaml#"
+ allOf:
+ - $ref: "partition.yaml#"
+ - if:
+ properties:
+ compatible:
+ contains:
+ const: sercomm,sc-partitions
+ then:
+ properties:
+ sercomm,scpart-id:
+ description: Partition id in Sercomm partition map. Mtd
+ parser uses this id to find a record in the partiton map
+ containing offset and size of the current partition. The
+ values from partition map overrides partition offset and
+ size defined in reg property of the dts. Frequently these
+ values are the same, but may differ if device has bad
+ eraseblocks on a flash.
+ $ref: /schemas/types.yaml#/definitions/uint32
> Best regards,
> Krzysztof
--
Best regards,
Mikhail
