Re: [PATCH 1/3] ALSA: hda/tegra: Skip reset on BPMP devices

From: Sameer Pujar
Date: Tue Dec 07 2021 - 12:38:14 EST




On 12/7/2021 9:05 PM, Dmitry Osipenko wrote:
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07.12.2021 17:49, Sameer Pujar пишет:
...
How the reload case would be different? Can you please specify more
details if you are referring to a particular scenario?
You have a shared power domain. Since power domain can be turned off
only when nobody keeps domain turned on, you now making reset of HDA
controller dependent on the state of display driver.
I don't think that the state of display driver would affect. The HDA
driver itself can issue unpowergate calls which in turn ensures h/w
reset. If display driver is already runtime active, HDA driver runtime
resume after this would be still fine since h/w reset is already applied
during display runtime resume. Note that both HDA and display resets are
connected to this power-domain and BPMP applies these resets during
unpowergate.
HDA won't be reset while display is active on T186+.

No. HDA reset is applied whenever power-domain is ungated. It can happen when either HDA or display device becomes active. So I don't think that it is inconsistent.