Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
MIME-Version: 1.0
References: <20191014141718.22603-1-narmstrong@baylibre.com>
 <20191014141718.22603-2-narmstrong@baylibre.com> <20191023201141.GA21235@bogus>
 <CA+3zgmsJPsvXgsjDQKKrSG+UNdY3SK+hKCTD2X3hGG+OXejHig@mail.gmail.com> <CAKgpwJWU3jB0DWEKE09TOV+YLceBFJ75ZirAXQbuhj8v3FwjXg@mail.gmail.com>
In-Reply-To: <CAKgpwJWU3jB0DWEKE09TOV+YLceBFJ75ZirAXQbuhj8v3FwjXg@mail.gmail.com>
From:   Tim <elatllat@gmail.com>
Date:   Mon, 11 Nov 2019 09:05:27 -0500
Message-ID: <CA+3zgmtJqN-3Q-kjMhh58B+T7z_1TA-C6be7+UP6nuQb7eq=8A@mail.gmail.com>
Subject: Re: [PATCH 1/3] doc: dt: bindings: usb: dwc3: Update entries for
 disabling SS instances in park mode
To:     Jun Li <lijun.kernel@gmail.com>
Cc:     Neil Armstrong <narmstrong@baylibre.com>,
        Felipe Balbi <balbi@kernel.org>, khilman@baylibre.com,
        devicetree@vger.kernel.org, linux-usb@vger.kernel.org,
        linux-amlogic@lists.infradead.org,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        Dongjin Kim <tobetter@gmail.com>,
        Jianxin Pan <jianxin.pan@amlogic.com>,
        Rob Herring <robh@kernel.org>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

Speculation;

Maybe the kernel maintainers prefer to optimistically permit future
products to easily remove workarounds via quirk flags.
Even if data from testing were shown, and it did not impact
performance, code reduction and clarity are desirable.

On Sun, Nov 10, 2019 at 8:58 PM Jun Li <lijun.kernel@gmail.com> wrote:
>
> Hi Neil
>
> As I got the information from Synopsys, this bug exists on current IP ver=
sions,
> and per my tests with external USB3 hub + 2 Super speed udisks on data
> read by dd, I can reproduce this issue with different kernel versions, al=
so I
> didn't see obvious performance drop by dd tests after disable park mode f=
or
> super speed, so should we just disable it by default so no need a quirk?
>
> Li Jun
>
> Tim <elatllat@gmail.com> =E4=BA=8E2019=E5=B9=B411=E6=9C=8811=E6=97=A5=E5=
=91=A8=E4=B8=80 =E4=B8=8A=E5=8D=888:42=E5=86=99=E9=81=93=EF=BC=9A
> >
> > Thanks for working on this Neil,
> > Is there something that needs doing for this patch to make it into 5.3 =
or 5.4?
> > As previously mentioned the patch set fixes the issue on affected hardw=
are;
> >     https://patchwork.kernel.org/patch/11164515/
> >
> >
> >
> > On Wed, Oct 23, 2019 at 4:11 PM Rob Herring <robh@kernel.org> wrote:
> > >
> > > On Mon, Oct 14, 2019 at 04:17:16PM +0200, Neil Armstrong wrote:
> > > > This patch updates the documentation with the information related
> > > > to the quirks that needs to be added for disabling all SuperSpeed X=
HCi
> > > > instances in park mode.
> > > >
> > > > CC: Dongjin Kim <tobetter@gmail.com>
> > > > Cc: Jianxin Pan <jianxin.pan@amlogic.com>
> > > > Reported-by: Tim <elatllat@gmail.com>
> > > > Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
> > > > ---
> > > >  Documentation/devicetree/bindings/usb/dwc3.txt | 2 ++
> > > >  1 file changed, 2 insertions(+)
> > >
> > > Sigh, what's one more to the never ending list of quirks...
> > >
> > > Acked-by: Rob Herring <robh@kernel.org>