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;
From:   Neil Armstrong <narmstrong@baylibre.com>
To:     jbrunet@baylibre.com
Cc:     Neil Armstrong <narmstrong@baylibre.com>,
        linux-amlogic@lists.infradead.org,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        linux-clk@vger.kernel.org
Subject: [PATCH 3/3] clk: meson: g12a: mark fclk_div3 as critical
Date:   Tue, 21 May 2019 17:01:30 +0200
Message-Id: <20190521150130.31684-4-narmstrong@baylibre.com>
In-Reply-To: <20190521150130.31684-1-narmstrong@baylibre.com>
References: <20190521150130.31684-1-narmstrong@baylibre.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On Amlogic Meson G12b platform, the fclk_div3 seems to be necessary for
the system to operate correctly.

Disabling it cause the entire system to freeze, including peripherals.

Let's mark this clock as critical, fixing boot on G12b platforms.

Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
---
 drivers/clk/meson/g12a.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/drivers/clk/meson/g12a.c b/drivers/clk/meson/g12a.c
index 81cb38ac3c85..575e58752aff 100644
--- a/drivers/clk/meson/g12a.c
+++ b/drivers/clk/meson/g12a.c
@@ -1244,6 +1244,16 @@ static struct clk_regmap g12a_fclk_div3 = {
 		.ops = &clk_regmap_gate_ops,
 		.parent_names = (const char *[]){ "fclk_div3_div" },
 		.num_parents = 1,
+		/*
+		 * This clock is used by the resident firmware and is required
+		 * by the platform to operate correctly.
+		 * Until the following condition are met, we need this clock to
+		 * be marked as critical:
+		 * a) Mark the clock used by a firmware resource, if possible
+		 * b) CCF has a clock hand-off mechanism to make the sure the
+		 *    clock stays on until the proper driver comes along
+		 */
+		.flags = CLK_IS_CRITICAL,
 	},
 };
 
-- 
2.21.0