[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <CAHp75VdacYoO2wpojPS1CDeJr-V=0U8JH=dx6p9soBswZ+D8JQ@mail.gmail.com>
Date: Sat, 27 May 2017 18:45:24 +0300
From: Andy Shevchenko <andy.shevchenko@...il.com>
To: Mika Westerberg <mika.westerberg@...ux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
Andreas Noever <andreas.noever@...il.com>,
Michael Jamet <michael.jamet@...el.com>,
Yehezkel Bernat <yehezkel.bernat@...el.com>,
Lukas Wunner <lukas@...ner.de>,
Amir Levy <amir.jer.levy@...el.com>,
Andy Lutomirski <luto@...nel.org>,
Mario Limonciello <Mario.Limonciello@...l.com>,
Jared.Dominguez@...l.com,
Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH v2 09/27] thunderbolt: Convert switch to a device
On Fri, May 26, 2017 at 7:09 PM, Mika Westerberg
<mika.westerberg@...ux.intel.com> wrote:
> Thunderbolt domain consists of switches that are connected to each
> other, forming a bus. This will convert each switch into a real Linux
> device structure and adds them to the domain. The advantage here is
> that we get all the goodies from the driver core, like reference
> counting and sysfs hierarchy for free.
>
> Also expose device identification information to the userspace via new
> sysfs attributes.
>
> In order to support internal connection manager (ICM) we separate switch
> configuration into its own function (tb_switch_configure()) which is
> only called by the existing native connection manager implementation
> used on Macs.
> + /*
> + * The newer controllers include fused UUID as part of link
> + * controller specific registers
> + */
> + cap = tb_switch_find_vsec_cap(sw, TB_VSEC_CAP_LINK_CONTROLLER);
> + if (cap > 0) {
> + tb_sw_read(sw, uuid, TB_CFG_SWITCH, cap + 3, 4);
> + } else {
> + /*
> + * By default the UUID will be based on UID where upper two
> + * dwords are filled with ones.
> + */
> + uuid[0] = sw->uid & 0xffffffff;
> + uuid[1] = (sw->uid >> 32) & 0xffffffff;
> + uuid[2] = 0xffffffff;
> + uuid[3] = 0xffffffff;
> + }
It might make sense to add some comment as we discussed earlier
(privately) about (non-)compatibiliness with UUID by spec and why 0xff
are used.
--
With Best Regards,
Andy Shevchenko
Powered by blists - more mailing lists