Re: [PATCH v6 3/4] regulator: qcom-rpmh: readback voltage/bypass/mode set during bootup

[Val Packett <val@packett.cool>]

Hi,

On 9/8/26 4:46 AM, Konrad Dybcio wrote:
> [..]
>> do you see the problem with the rpmh_read() or in the voltage range check?
> Applying
>
> 20260812-rpmh-timeout-debug-v1-v3-0-68c0a40dce23@oss.qualcomm.com
>
> I get:
>
> [   12.735771] qcom_rpmh RSC:apps_rsc
> [   12.739294] qcom_rpmh Request: tcs-in-use:YES state=2 wait_for_compl=1
> [   12.749622] qcom_rpmh TCS=0 [ctrlr-sts:BUSY amc-mode:0x1010000 irq-sts:WAITING]
> [   12.763769] qcom_rpmh        CMD=0 [addr=0x43100(VRM/smpc8) data=0x7 resp-required sts=triggered+sent-to-aoss]
> [   12.781024] qcom_rpmh Request: tcs-in-use:YES state=2 wait_for_compl=1
> [   12.797493] qcom_rpmh TCS=1 [ctrlr-sts:BUSY amc-mode:0x1010000 irq-sts:WAITING]
> [   12.811733] qcom_rpmh        CMD=0 [addr=0x40000(VRM/smpa5) data=0x0 resp-required sts=triggered+sent-to-aoss]
> [   12.829006] qcom_rpmh HW IRQ 37 is NOT PENDING at GIC
> [   12.843942] qcom_rpmh Completion is not done
> [   12.853536] qcom_rpmh ERROR: Accelerator(s) at AOSS did not respond
>
> Neither S8C nor S5A are "special", neither of them feeds an
> ARC resource (at a glance, anyway)
>
> so it's the read part,
>
> RPMH_REGULATOR_REG_VRM_VOLTAGE and RPMH_REGULATOR_REG_VRM_MODE stall
>
> RPMH_REGULATOR_REG_ENABLE interestingly doesn't

This happens with some LDOs on sc8180x as well…

I've been getting the "failed to read VOLTAGE ret = -110" error when 
enabling the L14A LDO (for cameras on the Surface Pro X). (And that 
breaks the entire boot)

With the "Skip read requests on unsupported platforms" patch, instead of 
that I get an error exactly like this one above, when it's being set to 
high power mode.

Even patching out the *writes* to mode/voltage specifically for ldo14, 
rpmh_regulator_set_enable_state on ldo14 crashes/stalls aoss (and at 
least in some dt configurations, boot proceeds but wifi/usb break) :(

But S5A, L7A, L9A, L12A were listed there normally from the start and 
never had this issue. S5A here did not have an issue even with the read 
code enabled.


~val