Comment #135 for bugzilla 237666 : a USB3-handling problem with a investigatory fix for a cortex-a72 context

[Hans Petter Selasky]

On 2020-09-19 21:58, Mark Millard wrote:
> In my context:
> 
> # svnlite diff /usr/src/sys/dev/usb/controller/xhci.c
> Index: /usr/src/sys/dev/usb/controller/xhci.c
> ===================================================================
> --- /usr/src/sys/dev/usb/controller/xhci.c	(revision 363590)
> +++ /usr/src/sys/dev/usb/controller/xhci.c	(working copy)
> @@ -431,6 +431,7 @@
>   
>   	phwr->hwr_ring_seg[0].qwEvrsTablePtr = htole64(addr);
>   	phwr->hwr_ring_seg[0].dwEvrsTableSize = htole32(XHCI_MAX_EVENTS);
> +	usb_bus_mem_flush_all(&sc->sc_bus, &xhci_iterate_hw_softc);
>   
>   	DPRINTF("ERDP(0)=0x%016llx\n", (unsigned long long)addr);
>   
> 
> The result booted just fine, no "Resetting controller" notices at

Could you add a comment describing the need for this flush? And then I 
think we can push that fix upstream!

--HPS