Re: [PATCH v16 08/40] gpu: host1x: Add initial runtime PM and OPP support

[Jon Hunter <jonathanh@nvidia.com>]

On 22/12/2021 09:47, Jon Hunter wrote:
> 
> On 21/12/2021 20:58, Dmitry Osipenko wrote:
>> Hi,
>>
>> Thank you for testing it all.
>>
>> 21.12.2021 21:55, Jon Hunter пишет:
>>> Hi Dmitry, Thierry,
>>>
>>> On 30/11/2021 23:23, Dmitry Osipenko wrote:
>>>> Add runtime PM and OPP support to the Host1x driver. For the starter we
>>>> will keep host1x always-on because dynamic power management require a
>>>> major
>>>> refactoring of the driver code since lot's of code paths are missing 
>>>> the
>>>> RPM handling and we're going to remove some of these paths in the 
>>>> future.
>>>
>>>
>>> Unfortunately, this change is breaking boot on Tegra186. Bisect points
>>> to this and reverting on top of -next gets the board booting again.
>>> Sadly, there is no panic or error reported, it is just a hard hang. I
>>> will not have time to look at this this week and so we may need to
>>> revert for the moment.
>>
>> Only T186 broken? What about T194?
> 
> Yes interestingly only Tegra186 and no other board.
> 
>> Which board model fails to boot? Is it running in hypervisor mode?
> 
> This is Jetson TX2. No hypervisor.
> 
>> Do you use any additional patches?
> 
> No just plain -next. The tests run every day on top of tree.
> 
>> Could you please test the below diff? I suspect that
>> host1x_syncpt_save/restore may be entirely broken for T186 since we
>> never used these funcs before.
>>
>> --- >8 ---
>>
>> diff --git a/drivers/gpu/host1x/dev.c b/drivers/gpu/host1x/dev.c
>> index f5b4dcded088..fd5dfb875422 100644
>> --- a/drivers/gpu/host1x/dev.c
>> +++ b/drivers/gpu/host1x/dev.c
>> @@ -580,7 +580,6 @@ static int __maybe_unused
>> host1x_runtime_suspend(struct device *dev)
>>       int err;
>>
>>       host1x_intr_stop(host);
>> -    host1x_syncpt_save(host);
>>
>>       err = reset_control_bulk_assert(host->nresets, host->resets);
>>       if (err) {
>> @@ -596,9 +595,8 @@ static int __maybe_unused
>> host1x_runtime_suspend(struct device *dev)
>>       return 0;
>>
>>   resume_host1x:
>> -    host1x_setup_sid_table(host);
>> -    host1x_syncpt_restore(host);
>>       host1x_intr_start(host);
>> +    host1x_setup_sid_table(host);
>>
>>       return err;
>>   }
>> @@ -626,9 +624,8 @@ static int __maybe_unused
>> host1x_runtime_resume(struct device *dev)
>>           goto disable_clk;
>>       }
>>
>> -    host1x_setup_sid_table(host);
>> -    host1x_syncpt_restore(host);
>>       host1x_intr_start(host);
>> +    host1x_setup_sid_table(host);
> 
> 
> Thanks! Will try this later, once the next bisect is finished :-)

I tested the above, but this did not fix it. It still hangs on boot.

Jon

-- 
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