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In-Reply-To: <1544720370-11598-1-git-send-email-jhugo@codeaurora.org>
Subject: Re: [PATCH] clk: qcom: Leave mmss noc on for 8998
To:     Jeffrey Hugo <jhugo@codeaurora.org>, andy.gross@linaro.org,
        david.brown@linaro.org, mturquette@baylibre.com
References: <1544720370-11598-1-git-send-email-jhugo@codeaurora.org>
Message-ID: <154472978059.19322.5895645487468845661@swboyd.mtv.corp.google.com>
From:   Stephen Boyd <sboyd@kernel.org>
User-Agent: alot/0.8
Cc:     bjorn.andersson@linaro.org, linux-arm-msm@vger.kernel.org,
        linux-clk@vger.kernel.org, linux-kernel@vger.kernel.org,
        marc.w.gonzalez@free.fr, Jeffrey Hugo <jhugo@codeaurora.org>
Date:   Thu, 13 Dec 2018 11:36:20 -0800
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

Quoting Jeffrey Hugo (2018-12-13 08:59:30)
> Similar to other qcom targets, gcc_mmss_noc_cfg_ahb_clk should not be
> disabled.  Any mmss access depends on this clock, and its been observed
> that enabling mmssnoc_axi_rpm_clk with rpmcc results in an implicit
> access to mmss and will crash the system if gcc_mmss_noc_cfg_ahb_clk is
> disabled.
>=20
> Signed-off-by: Jeffrey Hugo <jhugo@codeaurora.org>
> ---
>  drivers/clk/qcom/gcc-msm8998.c | 1 +
>  1 file changed, 1 insertion(+)
>=20
> diff --git a/drivers/clk/qcom/gcc-msm8998.c b/drivers/clk/qcom/gcc-msm899=
8.c
> index 4b75a09..b371308 100644
> --- a/drivers/clk/qcom/gcc-msm8998.c
> +++ b/drivers/clk/qcom/gcc-msm8998.c
> @@ -2014,6 +2014,7 @@ enum {
>                 .hw.init =3D &(struct clk_init_data){
>                         .name =3D "gcc_mmss_noc_cfg_ahb_clk",
>                         .ops =3D &clk_branch2_ops,
> +                       .flags =3D CLK_IGNORE_UNUSED,

It should be marked as CLK_IS_CRITICAL and a comment should be added to
the code indicating why it's critical.