On Mon, Nov 14, 2022 at 5:50 PM Dan Handley via TF-A <tf-a@lists.trustedfirmware.org> wrote:

Hi Wing/Okash

I know what OSI mode is supposed to deliver in theory – I just haven’t seen any compelling evidence of its benefit in practice. If you can share any evidence (even anecdotal) that would be great, although it’s not essential for these patches to proceed.

However, we are going to need some upstream platform(s) to exercise the new functionality. This can be a model platform, e.g. the Base FVP, not necessarily real hw. Are you able to at least get this running locally on Base FVP? I’m sure others can help with adding a config to the OpenCI.

I agree, we need a real h/w platform to add such support in TF-A so that it can be tested regularly.

We are relying on some vendor platform to test OSI upstream and have no idea if it continues to

work or broken as one of the platform claiming to support OSI just disabled those states in the

DT recently. I hope we don't get into a similar state in TF-A. Sorry I really love to see hardware

platform here so that it can be used for tested Linux kernel OSI support as well.

Regards,

Sudeep