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From:   Neil Armstrong <narmstrong@baylibre.com>
To:     khilman@baylibre.com, jbrunet@baylibre.com
Cc:     baylibre-upstreaming@groups.io,
        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 3/6] clk: meson: g12a: mark fclk_div3 as critical
Date:   Thu,  4 Apr 2019 17:05:15 +0200
Message-Id: <20190404150518.30337-4-narmstrong@baylibre.com>
In-Reply-To: <20190404150518.30337-1-narmstrong@baylibre.com>
References: <20190404150518.30337-1-narmstrong@baylibre.com>
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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.

This patch patch marks 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 14aaa02bb621..3554d1172169 100644
--- a/drivers/clk/meson/g12a.c
+++ b/drivers/clk/meson/g12a.c
@@ -1060,6 +1060,16 @@ 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