Re: [PATCH 1/2] soc: qcom: pd_mapper: Add X1E80100

Dmitry Baryshkov
2024-09-04T13:27:13Z

On 4 September 2024 15:40:44 EEST, Johan Hovold <johan@kernel.org> wrote:
>On Thu, Aug 22, 2024 at 09:28:26AM +0200, Johan Hovold wrote:
>> On Tue, Jul 30, 2024 at 11:04:58PM -0700, Chris Lew wrote:
>>
>> > GLINK has a concept that is called "intents". An intent is an object
>> > that signifies that a remote channel is ready to receive a packet
>> > through GLINK. Intents can be pre-emptively queued, or they can be
>> > requested by the sending entity. GLINK will not try to send or it will
>> > block until there is an intent available.
>> >
>> > Intents are exchanged with GLINK_CMD_INTENT packets. When Linux receives
>> > one of these packets we add it to an idr "riids".
>> >
>> > Example sending call:
>> > pmic_glink_send() --> rpmsg_send() --> qcom_glink_send() -->
>> > __qcom_glink_send() --> qcom_glink_request_intent()
>> >
>> > In __qcom_glink_send(), we check if there are any available intents in
>> > "riids", if there aren't any intents we request an intent through
>> > qcom_glink_request_intent(). This sends a GLINK_CMD_RX_INTENT_REQ packet
>> > to the remote and waits for a GLINK_CMD_RX_INTENT_REQ_ACK packet in
>> > return. This ack packet will have a field that says whether the intent
>> > has been granted or not. When linux gets this ack packet, we will wake
>> > up the thread waiting in qcom_glink_request_intent().
>> >
>> > The ECANCELED comes from qcom_glink_request_intent() when we receive a
>> > GLINK_CMD_RX_INTENT_REQ_ACK that has granted == false.
>> >
>> > On the firmware, when a glink channel is registered they can optionally
>> > fill in a handler for GLINK_CMD_RX_INTENT_REQ packets. If this handler
>> > is not configured, then a default one will be used where all
>> > GLINK_CMD_RX_INTENT_REQ packets will be responded with
>> > GLINK_CMD_RX_INTENT_REQ_ACK and granted == false. If a channel is
>> > implemented this way, then the only thing Linux can do is wait and retry
>> > until the remote queues the intents on its own accord.
>> >
>> > This would be my current guess as to what's happening based on this not
>> > being consistent and only seen every couple of reboots. A stop path
>> > problem sounds like it should happen every time, and we should also see
>> > the remoteproc prints related to powering down the adsp. The above race
>> > should be applicable to all platforms but depends on the speed of the
>> > ADSP vs the CPU.
>>
>> Thanks for the above. This indeed seems to match what I'm seeing as I
>> also reported here [1]:
>>
>> [ 9.539415] 30000000.remoteproc:glink-edge: qcom_glink_handle_intent_req_ack - cid = 9, granted = 0
>> [ 9.561750] qcom_battmgr.pmic_glink_power_supply pmic_glink.power-supply.0: failed to request power notifications
>>
>> [ 9.448945] 30000000.remoteproc:glink-edge: qcom_glink_handle_intent_req_ack - cid = 9, granted = 0
>> [ 9.461267] pmic_glink_altmode.pmic_glink_altmode pmic_glink.altmode.0: failed to send altmode request: 0x10 (-125)
>> [ 9.469241] qcom,apr 30000000.remoteproc:glink-edge.adsp_apps.-1.-1: Adding APR/GPR dev: gprsvc:service:2:1
>> [ 9.478968] pmic_glink_altmode.pmic_glink_altmode pmic_glink.altmode.0: failed to request altmode notifications: -125
>>
>> I assume we do not want to have every client driver implement a retry
>> loop for the first communication with the remote end, so can this be
>> handled by the pmic_glink driver somehow? For example, by not forwarding
>> state changes until some generic request has gone through?
>
>Has there been any progress on this issue? It's already been five weeks
>since my initial report and we're closing in on the merge window for
>6.12.

I have been on vacation for 3 weeks. If I can reproduce it on the hardware I have access to, I will work on it during the next few days.

> If this isn't resolved soon, I'll send patch to disable the
>in-kernel pd-mapper by marking it as broken.
>
>> And what about the audio service errors:
>>
>> [ 14.565059] PDR: avs/audio get domain list txn wait failed: -110
>> [ 14.571943] PDR: service lookup for avs/audio failed: -110
>>
>> Does this seem to be a separate (but related) issue or just a different
>> symptom?
>
>I can confirm that the audio breakage is also related to the in-kernel
>pd-mapper. I hit it after 30 reboots with the in-kernel pd-mapper, but
>have not seen it with the user space service (e.g. after 100+ reboots).
>
>> [1] https://lore.kernel.org/lkml/ZsRGV4hplvidpYji@hovoldconsulting.com/
>
>Johan