This is a note to let you know that I've just added the patch titled
clk: meson: g12a: mark fclk_div2 as critical
to the 5.8-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
clk-meson-g12a-mark-fclk_div2-as-critical.patch
and it can be found in the queue-5.8 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit b8581a433d62cc804507c9ec43df0d220f7fd342
Author: Stefan Agner <stefan@xxxxxxxx>
Date: Fri Aug 28 17:52:05 2020 +0200
clk: meson: g12a: mark fclk_div2 as critical
[ Upstream commit 2c4e80e06790cb49ad2603855d30c5aac2209c47 ]
On Amlogic Meson G12b platform, similar to fclk_div3, the fclk_div2
seems to be necessary for the system to operate correctly as well.
Typically, the clock also gets chosen by the eMMC peripheral. This
probably masked the problem so far. However, when booting from a SD
card the clock seems to get disabled which leads to a system freeze.
Let's mark this clock as critical, fixing boot from SD card on G12b
platforms.
Fixes: 085a4ea93d54 ("clk: meson: g12a: add peripheral clock controller")
Signed-off-by: Stefan Agner <stefan@xxxxxxxx>
Signed-off-by: Jerome Brunet <jbrunet@xxxxxxxxxxxx>
Tested-by: Anand Moon <linux.amoon@xxxxxxxxx>
Cc: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
Link: https://lore.kernel.org/r/577e0129e8ee93972d92f13187ff4e4286182f67.1598629915.git.stefan@xxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/clk/meson/g12a.c b/drivers/clk/meson/g12a.c
index 30c15766ebb16..05d032be15c8f 100644
--- a/drivers/clk/meson/g12a.c
+++ b/drivers/clk/meson/g12a.c
@@ -298,6 +298,17 @@ static struct clk_regmap g12a_fclk_div2 = {
&g12a_fclk_div2_div.hw
},
.num_parents = 1,
+ /*
+ * Similar to fclk_div3, it seems that 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,
},
};
