Re: [PATCH 1/3] arm64: dts: qcom: milos: Reduce rmtfs_mem size to 2.5MiB

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

On 3/23/26 1:32 PM, Luca Weiss wrote:
> On Mon Mar 23, 2026 at 10:51 AM CET, Konrad Dybcio wrote:
>> On 3/21/26 6:00 PM, Alexander Koskovich wrote:
>>> The rmtfs_mem region is currently sized at 6MiB but the default for
>>> milos downstream is 2.5MiB. This causes remoteproc crashes on devices
>>> that expect the smaller size:
>>>
>>> modem_ac.c:281:Access Control Error: Could not protect the region specified:Start:e1f00000 End:e2180000, PID:1
>>>
>>> Reduce the default to 2.5MiB to match the QCOM downstream config, and
>>> override the size for FP6.
>>>
>>> Signed-off-by: Alexander Koskovich <akoskovich@pm.me>
>>> ---
>>>  arch/arm64/boot/dts/qcom/milos-fairphone-fp6.dts | 4 ++++
>>>  arch/arm64/boot/dts/qcom/milos.dtsi              | 2 +-
>>>  2 files changed, 5 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/arch/arm64/boot/dts/qcom/milos-fairphone-fp6.dts b/arch/arm64/boot/dts/qcom/milos-fairphone-fp6.dts
>>> index 52895dd9e4fa..c0981ab731c4 100644
>>> --- a/arch/arm64/boot/dts/qcom/milos-fairphone-fp6.dts
>>> +++ b/arch/arm64/boot/dts/qcom/milos-fairphone-fp6.dts
>>> @@ -724,6 +724,10 @@ &remoteproc_wpss {
>>>  	status = "okay";
>>>  };
>>>  
>>> +&rmtfs_mem {
>>> +	reg = <0x0 0xe1f00000 0x0 0x600000>;
>>
>> +Luca
> 
> You didn't actually Cc me, but I found it on the mailing list anyways :)

Oops!


> 
>>
>> Could you please confirm that this was intentional in the first place?
>>
>> FWIW I see that volcano.dtsi indeed only requests 0x280_000 on a "clean"
>> Qualcomm tree
> 
> Yes, it's intentional that it's 6 MiB on Fairphone (Gen. 6):
> 
> https://gerrit-public.fairphone.software/plugins/gitiles/platform/vendor/qcom/proprietary/devicetree/+/b3744ffef87e1f2a232b26e9cb270a1f82554bc3%5E!/

"Root Cause: Requirement" :D

> 
> I think Fixes is appropriate since the default for Milos should be
> 0x280_000 and not 0x600_000?
> 
> Fixes: d9d59d105f98 ("arm64: dts: qcom: Add initial Milos dtsi")
> 
> And maybe a comment like this on top of the node?
> 
> /* Increase the size from 2.5 MiB to 6 MiB */

Yeah, sounds good

Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>

Konrad