Fwd: Re: kern/49076: USB 3.0 devices are not attached to xhci hubs

[Takahiro HAYASHI <t.hash425%gmail.com@localhost>]

(I would have to Cc this to netbsd-bugs@ explicitly.)

-------- Forwarded Message --------
Subject: Re: kern/49076: USB 3.0 devices are not attached to xhci hubs
Date: Thu, 04 Sep 2014 08:59:58 +0900
From: Takahiro HAYASHI <t.hash425%gmail.com@localhost>
To: gnats-bugs%NetBSD.org@localhost, kern-bug-people%netbsd.org@localhost, 
ryoon%NetBSD.org@localhost

On 08/31/14 20:40, Ryo ONODERA wrote:
[snip]
>   +static void
>   +xhci_pci_takecontroller(struct xhci_pci_softc *psc, int silent)
>   +{
>   +     uint32_t cparams, xecp, eec;
>   +     uint8_t bios_sem;
>   +     int i;
>   +
>   +     cparams = xhci_read_4(&psc->sc_xhci, XHCI_HCCPARAMS);
>   +     eec = -1;
>   +
>   +     /* Synchronise with the BIOS if it owns the controller. */
>   +     for (xecp = XHCI_HCC_XECP(cparams) << 2; xecp != 0;
>   +         xecp = XHCI_XECP_NEXT(eec) << 2) {
>   +             eec = xhci_read_4(&psc->sc_xhci, xecp);

This may not advance xecp correctly.
According to xHCI spec 1.1 section 7, XHCI_XECP_NEXT(eec)
indicates a relative offset in dword, "from this dword
to the beginning of the next extended capability".
That is, it should be:

xecp += XHCI_XECP_NEXT(eec) << 2;

unless XHCI_XECP_NEXT(eec) == 0.
Please see around ID_PROTOCOL in xhci_init() for detail.


--
t-hash