From: Stefan Sperling <stsp@stsp.name>
Subject: Re: xhci(4): Fix broken CSS on AMD 17h/6xh
To: Mark Kettenis <mark.kettenis@xs4all.nl>
Cc: moosetek4@gmail.com, tech@openbsd.org
Date: Thu, 19 Jun 2025 16:10:16 +0200

On Thu, Jun 19, 2025 at 03:55:31PM +0200, Mark Kettenis wrote:
> Sure. 

Thanks, committed.

> I'm wondering at what point we decide that all AMD XHCI
> controllers have this issue...

I also found an xhci-specific tweak you made to pci/pci.c in the
function pci_set_powerstate(), quoted below.

It seems this code was added before the CSS workaround was added.
Is it still needed?  The Z13 works fine without it.


	/* Some AMD Ryzen xHCI controllers need a bit more time to wake up. */
	id = pci_conf_read(pc, tag, PCI_ID_REG);
	if (PCI_VENDOR(id) == PCI_VENDOR_AMD) {
		switch (PCI_PRODUCT(id)) {
		case PCI_PRODUCT_AMD_17_1X_XHCI_1:
		case PCI_PRODUCT_AMD_17_1X_XHCI_2:
		case PCI_PRODUCT_AMD_17_6X_XHCI:
			d3_delay = 20 * 1000;
		default:
			break;
		}
	}