From 34138a59b92c1a30649a18ec442d2e61f3bc34dd Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Pawe=C5=82=20Chmiel?= <pawel.mikolaj.chmiel@gmail.com>
Date: Sat, 24 Oct 2020 17:43:46 +0200
Subject: [PATCH] clk: exynos7: Mark aclk_fsys1_200 as critical
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Git-commit: 34138a59b92c1a30649a18ec442d2e61f3bc34dd
Patch-mainline: v5.13-rc1
References: git-fixes
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), mark that clock as critical
so it won't be disabled.
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.
Fixes: 753195a749a6 ("clk: samsung: exynos7: Correct CMU_FSYS1 clocks names")
Signed-off-by: Paweł Chmiel <pawel.mikolaj.chmiel@gmail.com>
Acked-by: Krzysztof Kozlowski <krzk@kernel.org>
Link: https://lore.kernel.org/linux-clk/20201024154346.9589-1-pawel.mikolaj.chmiel@gmail.com
[s.nawrocki: Added comment in the code]
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/clk/samsung/clk-exynos7.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/drivers/clk/samsung/clk-exynos7.c b/drivers/clk/samsung/clk-exynos7.c
index 87ee1bad9a9a..4a5d2a914bd6 100644
--- a/drivers/clk/samsung/clk-exynos7.c
+++ b/drivers/clk/samsung/clk-exynos7.c
@@ -537,8 +537,13 @@ static const struct samsung_gate_clock top1_gate_clks[] __initconst = {
GATE(CLK_ACLK_FSYS0_200, "aclk_fsys0_200", "dout_aclk_fsys0_200",
ENABLE_ACLK_TOP13, 28, CLK_SET_RATE_PARENT |
CLK_IS_CRITICAL, 0),
+ /*
+ * This clock is required for the CMU_FSYS1 registers access, keep it
+ * enabled permanently until proper runtime PM support is added.
+ */
GATE(CLK_ACLK_FSYS1_200, "aclk_fsys1_200", "dout_aclk_fsys1_200",
- ENABLE_ACLK_TOP13, 24, CLK_SET_RATE_PARENT, 0),
+ ENABLE_ACLK_TOP13, 24, CLK_SET_RATE_PARENT |
+ CLK_IS_CRITICAL, 0),
GATE(CLK_SCLK_PHY_FSYS1_26M, "sclk_phy_fsys1_26m",
"dout_sclk_phy_fsys1_26m", ENABLE_SCLK_TOP1_FSYS11,
--
2.26.2