On 7/12/2023 12:24 PM, Melissa Wen wrote:
On 07/12, Pillai, Aurabindo wrote:
[Public]
Hi Guilherme,
Sorry there was one more patch which I missed to attach. Please add this 3rd
patch and retry.
Reverting that patch would cause high power consumption on Navi2x GPU also
cause hangs on certain multi monitor configurations. With these 3 patches,
you're getting the same effect as reverting the aforementioned patches, but it
makes the reverted sequence available only for Steam deck hardware.
Hi Jay,
Thanks for looking at this issue.
You mention power consumption and multi-monitor configuration issues
that can affect a driver if we revert this OTG change, and both sounds
quite relevant to me. Can they not affect DCN301 too? Is there something
that needs further work so the DCN301 can benefit from this improvement
as well?
Also, let us know if we can contribute in any way.
Hi Melissa,
Unfortunately, DCN301 does not support Firmware Assisted Memory Clock
Switching, which is the feature that gets blocked on Navi2x if we revert
the patch in question. This is the feature that enables lower power
consumption on some multi monitor configurations and high refresh rate
single monitor configurations.
Navi2x is configured to use FAMS in the driver, but without this change,
firmware wont be able to actually enable the feature in DMCUB, which
puts the driver in a unexpected state. On DCN301, this unexpected state
will not occur, because there is no FAMS support in driver nor firmware.
--
Jay
