Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Content-Type: text/plain; charset="utf-8"
MIME-Version: 1.0
Content-Transfer-Encoding: quoted-printable
In-Reply-To: <20210131170428.3290-1-pawel.mikolaj.chmiel@gmail.com>
References: <20210131170428.3290-1-pawel.mikolaj.chmiel@gmail.com>
Subject: Re: [PATCH v3] clk: exynos7: Keep aclk_fsys1_200 enabled
From:   Stephen Boyd <sboyd@kernel.org>
Cc:     s.nawrocki@samsung.com, tomasz.figa@gmail.com,
        cw00.choi@samsung.com, linux-samsung-soc@vger.kernel.org,
        linux-clk@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-kernel@vger.kernel.org, <pawel.mikolaj.chmiel@gmail.com>
To:     <pawel.mikolaj.chmiel@gmail.com>, kgene@kernel.org,
        krzk@kernel.org, mturquette@baylibre.com
Date:   Mon, 08 Feb 2021 23:48:21 -0800
Message-ID: <161285690197.418021.15554726449883492168@swboyd.mtv.corp.google.com>
User-Agent: alot/0.9.1
Precedence: bulk

Quoting (2021-01-31 09:04:28)
> This clock must be always enabled to allow access to any registers in
> fsys1 CMU. Until proper solution based on runtime PM is applied
> (similar to what was done for Exynos5433), fix this by calling
> clk_prepare_enable() directly from clock provider driver.
>=20
> It was observed on Samsung Galaxy S6 device (based on Exynos7420), where
> UFS module is probed before pmic used to power that device.
> In this case defer probe was happening and that clock was disabled by
> UFS driver, causing whole boot to hang on next CMU access.
>=20

Does this need a Fixes tag?