linux-kernel - Re: R: [PATCH v2] ARM: qcom: Disable i2c device on gsbi4 for ipq806x

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <158605625697.158626.12280118012638752686@swboyd.mtv.corp.google.com>
Date:   Sat, 04 Apr 2020 20:10:56 -0700
From:   Stephen Boyd <sboyd@...nel.org>
To:     'Andy Gross' <agross@...nel.org>, ansuelsmth@...il.com
Cc:     'Mathieu Olivari' <mathieu@...eaurora.org>,
        'Bjorn Andersson' <bjorn.andersson@...aro.org>,
        'Rob Herring' <robh+dt@...nel.org>,
        'Mark Rutland' <mark.rutland@....com>,
        'Michael Turquette' <mturquette@...libre.com>,
        linux-arm-msm@...r.kernel.org, devicetree@...r.kernel.org,
        linux-kernel@...r.kernel.org, linux-clk@...r.kernel.org
Subject: Re: R: [PATCH v2] ARM: qcom: Disable i2c device on gsbi4 for ipq806x

Quoting ansuelsmth@...il.com (2020-04-02 18:39:04)
> 
> 
> > -----Messaggio originale-----
> > Da: Stephen Boyd <sboyd@...nel.org>
> > Inviato: venerdì 3 aprile 2020 03:34
> > A: Andy Gross <agross@...nel.org>; Ansuel Smith
> > <ansuelsmth@...il.com>
> > Cc: Ansuel Smith <ansuelsmth@...il.com>; Mathieu Olivari
> > <mathieu@...eaurora.org>; Bjorn Andersson
> > <bjorn.andersson@...aro.org>; Rob Herring <robh+dt@...nel.org>; Mark
> > Rutland <mark.rutland@....com>; Michael Turquette
> > <mturquette@...libre.com>; linux-arm-msm@...r.kernel.org;
> > devicetree@...r.kernel.org; linux-kernel@...r.kernel.org; linux-
> > clk@...r.kernel.org
> > Oggetto: Re: [PATCH v2] ARM: qcom: Disable i2c device on gsbi4 for
> > ipq806x
> > 
> > Quoting Ansuel Smith (2020-03-30 13:56:46)
> > > diff --git a/drivers/clk/qcom/gcc-ipq806x.c b/drivers/clk/qcom/gcc-
> > ipq806x.c
> > > index b0eee0903807..f7d7a2bc84c1 100644
> > > --- a/drivers/clk/qcom/gcc-ipq806x.c
> > > +++ b/drivers/clk/qcom/gcc-ipq806x.c
> > > @@ -991,6 +991,7 @@ static struct clk_branch gsbi4_h_clk = {
> > >                 .hw.init = &(struct clk_init_data){
> > >                         .name = "gsbi4_h_clk",
> > >                         .ops = &clk_branch_ops,
> > > +                       .flags = CLK_IGNORE_UNUSED,
> > 
> > Is this necessary? Shouldn't we skip clks that are protected during the
> > unused phase?
> > 
> 
> gsbi4_h_clk is not protected. gsbi4_h_clk needs to not be disabled if unused
> (as it's used by rpm) but can't be protected since it's used by uart gsbi4.
> (With some test protecting also this clk cause the malfunction of uart gsb4)
> 

Who owns gsbi4 on this platform? Is it RPM? If so, it should be
protected and we shouldn't touch this clk from the kernel.