Re: [PATCH 3/5] dt-bindings: firmware: qcom,scm: Document reboot mode

[Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>]

On 11/12/25 5:36 PM, Bjorn Andersson wrote:
> On Wed, Nov 05, 2025 at 10:44:05AM +0100, Konrad Dybcio wrote:
>> On 11/4/25 10:19 PM, Loic Poulain wrote:
>>> On Tue, Nov 4, 2025 at 3:12 AM Bjorn Andersson <andersson@kernel.org> wrote:
>>>>
>>>> On Mon, Nov 03, 2025 at 07:20:04PM +0100, Loic Poulain wrote:
>>>>> SCM can be used to support reboot mode such as Emergency Recovery Mode.
>>>>
>>>> "such as"? Do we have any other useful bits in here?
>>>
>>>  I heard we may have different EDL modes supported like USB or SD
>>> based EDL, but I don't know much about the details.
>>>
>>>>
>>>>>
>>>>> Signed-off-by: Loic Poulain <loic.poulain@oss.qualcomm.com>
>>>>> ---
>>>>>  Documentation/devicetree/bindings/firmware/qcom,scm.yaml | 4 ++++
>>>>>  1 file changed, 4 insertions(+)
>>>>>
>>>>> diff --git a/Documentation/devicetree/bindings/firmware/qcom,scm.yaml b/Documentation/devicetree/bindings/firmware/qcom,scm.yaml
>>>>> index b913192219e4..c8bb7dacd900 100644
>>>>> --- a/Documentation/devicetree/bindings/firmware/qcom,scm.yaml
>>>>> +++ b/Documentation/devicetree/bindings/firmware/qcom,scm.yaml
>>>>> @@ -121,6 +121,10 @@ properties:
>>>>>            - description: offset of the download mode control register
>>>>>      description: TCSR hardware block
>>>>>
>>>>> +patternProperties:
>>>>> +  "^mode-.*$":
>>>>
>>>> I'd only ever expect mode-edl = <1>. Do we have additional modes that
>>>> warrant the generic nature of this?
>>>
>>> We may extend this to mode-ramdump if it makes sense, but as of now
>>> it's indeed only edl, will fix it.
>>
>> Would adding ramdump here be a matter of:
>>
>> + mode-ramdump = <0xmagic>
>>
>> ?
>>
>> If so, please add it too
>>
> 
> But what does that mean? "Hey computer, perform a graceful shutdown and
> when you're done, give me a ramdump"?

I.. guess?

Perhaps it could be useful for registering a panic handler to reboot
into ramdump in case that's not enabled by deafult (but is that
possible with our fw?)

Konrad